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Article
Metabolic Reprogramming
Induces Germinal CenterB Cell Differentiation through Bcl6 LocusRemodelingGraphical Abstract
Highlights
d IL-4-signaling induces Bcl6 expression and GC B cell
differentiation
d IL-4 alters TCA cycle to accumulate aKG, a cofactor for
H3K27-demethylase
d STAT6 recruits H3K27-demethylase UTX, leading to
activation of the Bcl6 locus
d GC B cell development requires aKG and enzymes regulating
aKG level
Haniuda et al., 2020, Cell Reports 33, 108333November 3, 2020 ª 2020 The Author(s).https://doi.org/10.1016/j.celrep.2020.108333
Authors
Kei Haniuda, Saori Fukao,
Daisuke Kitamura
[email protected] (K.H.),[email protected] (D.K.)
In Brief
The germinal center reaction is vital for
long-lasting humoral immunity, yet
molecular mechanisms underlying the
induction of Bcl6, the master regulator for
germinal center B cell differentiation,
remain unclear. Haniuda et al. show that
IL-4-signaling induces Bcl6 expression
by reprogramming the TCA cycle
metabolism that controls epigenomic
remodeling.
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llArticle
Metabolic Reprogramming InducesGerminal Center B Cell Differentiationthrough Bcl6 Locus RemodelingKei Haniuda,1,* Saori Fukao,1 and Daisuke Kitamura1,2,*1Division ofMolecular Biology, Research Institute for Biomedical Sciences (RIBS), TokyoUniversity of Science, Noda, Chiba 278-0022, Japan2Lead Contact
*Correspondence: [email protected] (K.H.), [email protected] (D.K.)
https://doi.org/10.1016/j.celrep.2020.108333
SUMMARY
The germinal center (GC) reaction is essential for long-lived humoral immunity. However, molecular require-ments for the induction of Bcl6, the master regulator for GC B cell differentiation, remain unclear. Throughscreening forcytokinesandother stimuli that regulateBcl6expression,we identify IL-4as thestrongest inducer.IL-4 signaling alters the metabolomic profile in activated B cells and induces accumulation of the TCA cycle in-termediate a-ketoglutarate (aKG), which is required for activation of theBcl6 gene locus. Mechanistically, afterIL-4 treatment, STAT6 bound to the known enhancers in the Bcl6 locus recruits UTX, a demethylase for therepressive histone mark H3K27me3 that requires aKG as a cofactor. In turn, the H3K27me3 demethylation ac-tivates the enhancers and transcription of theBcl6 gene.Wepropose that IL-4-mediatedmetabolic reprogram-ming in B cells is pivotal for epigenomic activation of Bcl6 expression to promote GC B cell differentiation.
INTRODUCTION
One of the hallmarks of the adaptive immune response is the
generation of immunological memory. Long-lived memory B
cells and plasma cells (PCs) with high affinity for antigen are
formed in the germinal center (GC) through B cell proliferation,
somatic hypermutation (SHM) and affinity-based selection (Vic-
tora and Nussenzweig, 2012). Thus, GC formation is essential
for efficient adaptive immune responses. Upon antigen recogni-
tion by their B cell receptor (BCR), B cells interact with cognate
T cells and are activated by signals through CD40 and cytokine
receptors, determining their cell fate. Only B cells expressing
the transcriptional repressor Bcl6 can differentiate into GC B
cells. Bcl6 is the master regulator for GC B cell differentiation;
it directly suppresses the expression of many genes involved
in signal transduction throughBCR andCD40, PC differentiation,
cell-cycle arrest, and DNA damage responses (Basso and Dalla-
Favera, 2012). Therefore, Bcl6 expression prevents premature
activation and terminal differentiation, and makes it possible
for GC B cells to undergo massive proliferation, SHM, and the
consequent affinity maturation (Basso and Dalla-Favera, 2012).
Although the function of Bcl6 has been studied in detail, the mo-
lecular mechanisms underlying the induction of Bcl6 expression
remain elusive. This is mainly due to the lack of an in vitro system
in which Bcl6 expression can be reliably induced.
Immune cell activation is accompanied by metabolic reprog-
ramming to meet increased bioenergetic and biosynthetic de-
mands for cellular growth and proliferation (Pearce et al., 2013).
Once activated, lymphocytes engage in aerobic glycolysis, pro-
ducing lactate, rather than in mitochondrial oxidative metabolism,
CThis is an open access article under the CC BY-N
even in the presenceof oxygen. This process is knownas theWar-
burg effect, a common feature of actively proliferating cells, which
allows cells to produce ATP quickly and to generate themetabolic
intermediates required for biosynthesis (Vander Heiden et al.,
2009). Thus, after BCR or CD40 stimulation, B cells dramatically
increase glycolytic activity (Woodland et al., 2008). Furthermore,
among highly proliferative GC B cells, a fraction of light-zone B
cells that can receive T cell help activate mammalian target of ra-
pamycin complex 1 (mTORC1) signaling and express c-Myc, both
of which positively regulate glycolysis and anabolic metabolism
and are required for GC development (Calado et al., 2012; Domi-
nguez-Sola et al., 2012; Ersching et al., 2017).
A growing body of evidence suggests that some metabolic
pathways influence epigenetic gene regulation by providing do-
nors and cofactors for epigenetic modifiers. For example, the
threonine-fueled metabolism in embryonic stem cells (ESCs)
provides S-adenosylmethionine, the methyl-group donor for
methylation, to maintain the histone methylation required for plu-
ripotency (Shyh-Chang et al., 2013). Another example is that
enhanced glycolysis elevates cytosolic acetyl-coenzyme A
(CoA), a universal donor for acetylation, to enhance histone acet-
ylation and expression of Ifng in activated T cells (Peng et al.,
2016). Furthermore, the accumulation of the tricarboxylic acid
(TCA) cycle intermediate a-ketoglutarate (aKG), a required
cofactor for Jumonji C domain-containing (JmjC) histone deme-
thylases and ten-eleven translocation (TET) DNA dioxygenases,
has been reported to be required for maintaining the pluripo-
tency of ESCs (Carey et al., 2015) and primordial germ cells
(Tischler et al., 2019) and for activating effector gene programs
in T cells (Chisolm et al., 2017).
ell Reports 33, 108333, November 3, 2020 ª 2020 The Author(s). 1C-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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To date, it is unknown whether B cell metabolism can control
differentiation gene programs beyondmeeting their bioenergetic
and biosynthetic demands. Here, we demonstrated that IL-4-
mediated reprogramming of TCA cycle metabolism drives the
accumulation of aKG that integrates epigenetic activation of
the Bcl6 gene to induce GC B cell differentiation.
RESULTS
IL-4 Signaling and Mitochondrial Metabolism ControlBcl6 ExpressionTo elucidate the mechanisms upregulating Bcl6 expression in B
cells at a molecular level, we used our previously reported B cell
culture system called ‘‘iGB culture’’ (Nojima et al., 2011). In this
system, splenic B cells are cultured with interleukin-4 (IL-4) on
feeder cells expressing CD40L and B-cell activating factor
BAFF (40LB) and extensively proliferate and efficiently undergo
class switching to immunoglobulin G1 (IgG1) and IgE. These B
cells (called iGB cells) express modest levels of Bcl6 mRNA (No-
jima et al., 2011) and protein (Figure 1A), probably because
chronic CD40 stimulation suppresses Bcl6 expression (Saito
et al., 2007; Zhang et al., 2017). ‘‘Plain culture’’ with medium
alone for 1 day after removal of the feeder cells at day 3 of the
iGB culture produced a distinct population of IgG1+ B cells highly
expressing Bcl6 (Figure 1A). However, 60%–70% of the IgG1+ B
cells remained Bcl6� after the plain culture, despite the preced-
ing stimulation. Thus, we sought to find stimuli that induce Bcl6
expression in activated B cells by screening cytokines and other
stimuli that could convert these Bcl6� cells into Bcl6+ cells.
We treated the iGB cells with a panel of cytokines and anti-
bodies (Abs) during the plain culture period for 1 day and then
analyzed them by flow cytometry. We found that IL-4, IL-6, IL-
13, and IL-21 increased the frequency of Bcl6+ cells among
IgG1+ cells, and that IL-4 was the most potent inducer (Figures
1B, 1C, and S1A). In contrast, BCR stimulation by anti-IgG Ab
strongly reduced the frequency of Bcl6+ cells, but instead
increased the CD138+ PC (Figures 1B, 1C, and S1A). In line with
these data, IL-4 upregulated Bcl6 mRNA expression, whereas
anti-IgG Ab downregulated it and upregulated Irf4 expression
(Figure 1D). To assess the impact of IL-4 on GC development,
we administered IL-4 complexedwith an anti-IL4Ab (IL-4c), which
extends the bioactive half-life of the cytokine (Finkelman et al.,
1993) into immunizedmice during the early stage ofGC formation.
IL-4c treatment significantly increased the number of (4-hydroxy-
3-nitrophenyl)acetyl (NP)-specific GC B cells (Figure S1D).
Given that cellular metabolism has been reported to be linked
to gene expression and differentiation (Pearce et al., 2013), we
next assessed the metabolic properties of the iGB cells after
stimulation during the plain culture period. We measured mito-
chondrial membrane potential (DJm) intimately linked to elec-
tron transport chain (ETC) activity by stainingwith the fluorescent
dye TMRM (tetramethylrhodamine, methyl ester, perchlorate).
We found that stimulation with IL-4 increased the DJm of iGB
cells, whereas anti-IgG stimulation decreased it, as compared
to non-stimulated cultures (Figure 1E). Next, we measured
lactate production 4 h after stimulation and found that anti-IgG
but not IL-4 facilitated its production (Figure 1F). These data indi-
cated that IL-4-receptor (IL-4R) or BCR signaling activates mito-
2 Cell Reports 33, 108333, November 3, 2020
chondrial or glycolytic metabolism, respectively. The inhibition of
mitochondrial oxidative metabolism by treatment with oligomy-
cin, an inhibitor of the mitochondrial ETC (Figure S1E), abolished
Bcl6 upregulation after IL-4 stimulation, but not PC differentia-
tion by anti-IgG (Figure 1G). These findings suggest that IL-4
signaling upregulates Bcl6 expression through potentiating
mitochondrial oxidative metabolism.
GC B Cell Development Depends on MitochondrialOxidative MetabolismGiven theuniquedependencyofBcl6expressiononmitochondrial
oxidative metabolism, we decided to characterize the metabolic
status of B cell subsets that develop after antigen challenge. To
identify antigen-specific precursors of GC B cells (pre-GC B cell)
and GC B cells, we transferred naive B (NB) cells from CD45.1
mice carrying a knockin allele encoding a hapten NP-specific VH
region (B1-8hi) into C57BL/6 (B6) mice, which were immunized
with a conjugate of NP and chicken g-globulin (CGG) in alum the
next day. Among the donor-derived B220+ NP-binding B cells,
pre-GCB cells were defined asGL7+ CD38hi cells on day 3.5 after
immunization and GC B cells as GL7+ CD38lo cells on day 7. We
analyzed these cells, aswell asPCsonday 7 andNBcells fromun-
immunized mice (Figures 2A and S2A), for mitochondrial mass,
DJm, and mitochondrial reactive oxygen species (ROS) by stain-
ingwithMitoTracker, TMRM, orMitoSOX, respectively.Mitochon-
drial mass, DJm, and mitochondrial ROS were higher in pre-GC
and GC B cells than in NB cells or PCs (Figure 2B), suggesting
activated mitochondrial metabolism in pre-GC and GC B cells.
Glycolytic activity, assessed by the uptake of 2-NBDG (2-(N-(7-ni-
trobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose; a fluores-
cent analog of glucose) and production of lactate (an end product
of glycolysis) was markedly high in pre-GC B cells and PCs and
modest but higher than in NB cells in GC B cells (Figures 2B and
2C). The enzymatic activity of pyruvate dehydrogenase (PDH),
which promotes pyruvate entry into the TCA cycle at the expense
of lactate production (Figure S1E), was increased in GC B cells
compared with NB cells or PCs (Figures 2D and S2C), with a
concomitant decrease in the inhibitory PDH phosphorylation in
GC B cells (Figure S2D). These data indicate that GC B cells
have activatedmitochondrial oxidativemetabolismand restrained
aerobic glycolysis, suggesting that the Warburg effect may not fit
overall GC B cells, even though GC B cells display an increased
cellular size, intimately linked to biosynthesis, and the highest pro-
liferative capacity of any of the B cell subsets (Figures 2B and 2E).
To address the requirement for mitochondrial oxidative meta-
bolism in each B cell subset, we treated immunizedmice with oli-
gomycin for 1 day before analysis (Figure 2F). The administration
of oligomycin partially but significantly reduced the number of
GC B cells, but not of pre-GC B cells, PCs, or follicular helper
T (Tfh) cells (known to be required for GC formation) (Victora
and Nussenzweig, 2012), and attenuated the expression of
Bcl6 in GC B cells but not in Tfh cells (Figures 2G, 2H, and
S2E–S2G). In addition, inhibition of the first step of glycolysis
by administrating 2-deoxyglucose at the same time point also
diminishedGCB cell numbers (data not shown), as reported pre-
viously (Jellusova et al., 2017). Our results show that GC B cell
development relies on mitochondrial oxidative metabolism,
possibly fueled by glycolysis.
A B
C D
E F G
Figure 1. IL-4 and Mitochondrial Metabolism Regulate Bcl6 Expression
(A) Schema of the iGB culture followed by the plain culture and flow cytometric profiles of IgG1+ gated cells at the end of each culture.
(B) Quantification of Bcl6+ or CD138+ cells among IgG1+ cells after the plain culture with the indicated cytokines or Abs for 1 day. The results are presented as
relative to the cells cultured in medium alone.
(C–G) Analysis of IgG1+ iGB cells (gated as in Figure S1B) after the plain culture in medium alone (�) or with IL-4 or anti-IgG for 1 day.
(C) Flow cytometric analysis.
(D) qRT-PCR analysis of sorted IgG1+ cells (Figure S1C).
(E) TMRM staining.
(F) Lactate production by the sorted cells after the plain culture for 4 h.
(G) Analysis as in (C), except additional supplement of oligomycin or vehicle alone (�) in culture.
Data are means ± SDs of 2–4 (B) or 3 (F) biological replicates or 3 technical replicates (D). Each symbol represents a biologically independent sample (B and F).
The data are pooled from 2–4 independent experiments (B), or representative of at least 3 (A, C, and D) or 2 (E–G) independent experiments. p values were
calculated by 1-way ANOVA with Tukey’s test (F). See also Figure S1.
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IL-4 Signaling Reprograms B Cell Metabolome toAccumulate the TCA Cycle Intermediate aKGTo elucidate how mitochondrial metabolism contributes to the in-
duction of Bcl6 expression, we profiled the metabolome of iGB
cells treated with IL-4 or anti-IgG for 6 h, or untreated, without
feeder cells (Figure 3A). At this time point, expression levels of
Bcl6 and Blimp1 mRNA were unchanged (Figure S3A). The
metabolite profiling revealed different alterations between the
Cell Reports 33, 108333, November 3, 2020 3
A B
C D E F
G H
Figure 2. GC B Cells Depend on Mitochondrial Metabolism for Their Development(A–E) Characterization of the metabolic status of B cell subsets in the spleen.
(A) Experimental protocol for (B), (C) and (E). Each subset was defined as in Figure S2A.
(B) Mean fluorescent intensity (MFI) of MitoTracker, TMRM, MitoSOX or 2-NBDG, or forward scatter (FSC).
(C) Lactate production by sorted cells during 4-h ex vivo culture.
(D) Mitochondrial PDH activity in the cells prepared as in Figure S2B.
(E) Flow cytometric analysis for in vivo bromodeoxyuridine (BrdU) incorporation.
(F–H) In vivo treatment with oligomycin or vehicle alone (�).
(F) Experimental protocol. Each subset was defined as in Figure S2A.
(G) The number of indicated cells per spleen.
(H) MFI of Bcl6- or Irf4-staining.
Data are means ± SDs of 6 (B), 3 (C and D), 5 (E) or 7 (G and H) biological replicates. Each symbol represents an individual mouse (B, E, G, and H) or a biological
sample pooled from n = 2 (NB; C and D), 10 (pre-GC B, GC B, and PC; C), or 30 mice (GC B and PC; D). The data are representative of 2 (B, E, G, and H) in-
dependent experiments, or are pooled from 3 independent experiments (C and D). p values were calculated by 1-way ANOVA with Tukey’s test (B–E) or 2-tailed
unpaired Student’s t test (G and H). See also Figure S2.
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cells stimulated with IL-4 or anti-IgG (Figure S3B), among which
the TCA cycle was the most significantly altered pathway (Fig-
ure 3B). Among the TCA cycle metabolites, the amount of aKG
was strikingly higher in the cells stimulated with IL-4 than anti-
4 Cell Reports 33, 108333, November 3, 2020
IgG or the unstimulated cells (Figure 3C). Kinetics analysis demon-
strated that the amount of aKG was elevated by 6 h and then
became almost stable at least until 24 h after stimulation with IL-
4 (Figure S3C). However, the lactate:pyruvate ratio was highest
A C D
B
E F G H
KJI
Figure 3. IL-4 Induces aKG Accumulation That Stimulates Bcl6 Expression(A–D) Metabolome analysis of IgG1+ iGB cells stimulated with IL-4 or anti-IgG for 6 h or left unstimulated (�) for 1 h.
(A) Outline of the experiment.
(B) Metabolite set enrichment analysis selecting the top 15 most enriched metabolic pathways by treatment with IL-4 compared to anti-IgG, listed from top to
bottom according to p value.
(C) Abundance of TCA cycle-related metabolites.
(D) Lactate/pyruvate ratios.
(E) Amount of aKG in NB or GC B cells prepared as in Figure S2B.
(F) Amount of aKG in IgG1+ iGB cells after the plain culture for 6 h with IL-4 in the presence or absence of oligomycin.
(G–K) Effects of DMaKG or DE-Suc supplementation in low (Lo) glucose (Glc) culture.
(G) Experimental protocol.
(H) qRT-PCR analysis of iGB cells treated as indicated.
(I) Flow cytometric estimation of Fixable viability dye (FVD)-negative cells among total cells treated as indicated.
(J) qRT-PCR analysis of the same cells as in (I).
(K) Analysis of spleens of the cell-transferred mice on day 8 after immunization. Shown are the numbers of donor GC B cells
(CD45.1+NP+GL7+CD19+CD138�CD38lo) per spleen (right) estimated from flow cytometric analysis (left; numbers indicate frequency among live lymphocytes).
(legend continued on next page)
Cell Reports 33, 108333, November 3, 2020 5
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in the anti-IgG-stimulated cells, suggesting increased aerobic
glycolysis, which consumes pyruvate for producing lactate and
limits the TCA cycle (Figure 3D). Similarly, ex vivoGC B cells con-
tained a higher amount of aKG than NB cells (Figure 3E). We next
assessed the impact of mitochondrial oxidative metabolism on
the intracellular aKG levels. In accord with a previous report that
ETC inhibitors lower the aKG level (Fendt et al., 2013), treatment
with oligomycin during the IL-4 stimulation significantly decreased
the amount of aKG in iGB cells (Figure 3F).
Given the parallel effects of oligomycin in suppressing both IL-
4-induced aKG accumulation (above) and Bcl6 expression (Fig-
ure 1G), as well as in vivo GC development and Bcl6 expression
(Figures 2G and 2H), we next sought to reveal the molecular link
between aKG and Bcl6 expression. For this purpose, iGB cells
were plain cultured with IL-4 under low glucose conditions to limit
aKG production via the TCA cycle and supplemented or not with
dimethyl-aKG (DMaKG), a cell-permeable aKG derivative (Fig-
ure 3G). Under the low glucose conditions, the expression of
Bcl6 was mostly abolished, while supplementation with DMaKG
restored the expression ofBcl6 but not of Irf4 (Figure 3H). Supple-
mentation with diethyl-succinate (DE-Suc), a cell-permeable de-
rivative of succinate that is a downstream metabolite of aKG in
the TCA cycle, did not restoreBcl6 expression but viability of cells
cultured under low glucose conditions (Figures 3I and 3J). These
data suggest that Bcl6 expression is driven by aKG produced in
the glucose-fueled TCA cycle in IL-4-stimulated cells and that
this aKG function is distinct from a general role of TCA cycle me-
tabolites on energy production. To test the effect of aKG on GC B
cell differentiation, we cultured B1-8hi B cells under the same con-
ditions as above and transferred them into NP-CGG-immunized
B6 mice (Figure 3G). B cells cultured with low glucose barely
developed into GC B cells in vivo, but supplementation with
DMaKG rescued the GCB cell development (Figure 3K). Our find-
ings indicate that IL-4 signaling reprograms mitochondrial meta-
bolism in activated B cells, which in turn accumulates aKG and
drives the expression of Bcl6.
IL-4 Signaling Activates the Bcl6 Locus throughEpigenetic Remodeling Mediated by a-KGaKG is a cofactor for aKG-dependent dioxygenases, many of
which function as epigenetic modifiers, and the accumulation
of aKG is known to activate aKG-dependent histone demethy-
lases (Carey et al., 2015; Chisolm et al., 2017; Tischler et al.,
2019). Thus, we focused on the epigenetic regulation of Bcl6
expression.We found that in GCB cells, the global trimethylation
of histone H3 lysine 27 (H3K27me3), a repressive histone mark
contributing to chromatin compaction, was decreased and the
acetylation of H3K27 (H3K27Ac) was increased, whereas the tri-
methylation of H3K4 and H3K9 remained mostly unchanged as
compared with NB cells (Figure 4A).
We next analyzed published chromatin immunoprecipitation
(ChIP) coupled with high-throughput sequencing (ChIP-seq) data
Data aremeans ± SDs of 3 (C–F), 2 (I), and 5 (K) biological replicates or 3 technical
(C, D, F, and I), a biological sample pooled from n = 5 (NB in E) or 30 mice (GC B
experiments (F, H, J, and K), from an experiment (B–E), or pooled from 2 independe
(C, D, and K) or 2-tailed unpaired Student’s t test (E and F). See also Figure S3.
6 Cell Reports 33, 108333, November 3, 2020
ofNBcells andGCBcells, and found thatH3K27me3was reduced
in GCB cells in a region spanning from ~140 to ~360 kb upstream
of theBcl6 transcriptional start site (FigureS4A). This region largely
overlapped with two enhancer elements (enhancer 1 and 2) that
are activated specifically in GC B cells and interact with the Bcl6
promoter region (Bunting et al., 2016; Ryan et al., 2015). These
enhancer regions were enriched in GC B cells with an enhancer
mark H3K4me1 together with H3K27Ac (Figure S4A), a modifica-
tion associated with enhancer activity (Calo and Wysocka, 2013).
Knock out of these regions has been reported to result in a defec-
tive GC formation, indicating that these enhancers are crucial for
Bcl6 expression during GC B cell development (Bunting et al.,
2016). Our ChIP coupled with quantitative PCR (qPCR) analysis
confirmed that H3K27me3 was significantly lower in GC B cells
than in NB cells, in the same enhancer regions of the Bcl6 locus,
except for position �163 kb, where H3K27me3 was equally low
in NB cells (Figure 4B). Therefore, we hypothesized that the
H3K27me3marksat theBcl6enhancersareactivelydemethylated
to drive the transcription of the Bcl6 locus to promote GC B cell
development. To test this hypothesis, we assessed the histone
modifications in iGB cells treated with IL-4 or anti-IgG for 6 h in
comparison to untreated cells. Our ChIP-qPCR assay revealed
that treatment with IL-4 decreased H3K27me3 at enhancer 1
and 2 of the Bcl6 locus, again except for position �163 kb,
concomitant with an increase in H3K27Ac on the enhancer and
promoter regions (Figures 4C, 4D, andS4B). In contrast, treatment
with IL-4 or anti-IgG had no effect on H3K27me3 levels in both
enhancer and promoter regions of the Irf4 locus (Chapuy et al.,
2013; Raisner et al., 2018), although anti-IgG increased
H3K27Ac in these regions (Figures 4E, 4F, S4C, and S4D).
Given the dependence of Bcl6 expression on mitochondrial
oxidative metabolism that regulates aKG accumulation, we
next assessed whether IL-4-mediated reduction of H3K27me3
at the Bcl6 enhancers depends on this metabolism. First, we
demonstrated that treatment with oligomycin resulted in an in-
crease in H3K27me3 at the Bcl6 enhancers (Figure S4E) and a
marked decrease in Bcl6 mRNA expression that was partially
restored by the addition of DMaKG (Figure S4F). Second, to
determine whether aKG is required for the IL-4-mediated loss
of H3K27me3 in the Bcl6 enhancers, we treated glucose-
restricted iGB cells with DMaKG in the presence of IL-4.
Whereas H3K27me3 on enhancer 1 and 2 of the Bcl6 locus
was increased by the restriction of glucose, the addition of
DMaKG restored it to a lower level (Figure 4G). These data sug-
gested that IL-4 signaling induces epigenetic remodeling of the
Bcl6 locus and activates its enhancers through mechanisms de-
pending on mitochondrial oxidative metabolism and aKG.
An H3K27me3-Specific Demethylase UTX Is Requiredfor Bcl6 Induction and GC B Cell DevelopmentGiven the finding that aKG lowers H3K27me3 at the Bcl6
enhancers, we addressed the possible involvement of an
replicates (H and J). Each symbol represents a biologically independent sample
in E) or an individual mouse (K). The data are representative of 2 independent
nt experiments (I). p valueswere calculated by 1-way ANOVAwith Tukey’s test
A B G
C E
D F
Figure 4. aKG Supports IL-4-Mediated Epigenetic Changes in the Bcl6 Locus
(A and B) Immunoblot analysis of (A) and ChIP-qPCR analysis for H3K27me3 at the Bcl6 locus in (B) NB or GC B cells prepared as in Figure S2B. H3, histone H3.
(C–F) ChIP-qPCR analysis at the Bcl6 (C and D) or Irf4 (E and F) locus in IgG1+ iGB cells treated with IL-4 or anti-IgG for 6 h, or left unstimulated (�) for 1 h.
(G) ChIP-qPCR analysis at Bcl6 locus in IgG1+ iGB cells cultured with IL-4 for 6 h with the indicated supplements.
All of the ChIP-qPCR data were normalized to input DNA. The numbers on the x axis indicate the distance (kb) from TSS (+0). The data are means ± SDs of 3
biological replicates (B), each of which was pooled from n = 2 (NB) or 10mice (GC B); or of 3 technical replicates (C–G). The data are representative of 3 (A, C, and
D) or 2 (E–G) independent experiments or from an experiment (B). p values were calculated by 2-tailed unpaired Student’s t test (B). See also Figure S4.
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aKG-dependent H3K27me3-specific demethylase. Treatment of
iGB cells with GSK-J4 (Kruidenier et al., 2012), a potent inhibitor
of UTX (encoded by Kdm6a), resulted in an increase in
H3K27me3 at the Bcl6 enhancers and a concomitant reduction
in Bcl6 expression after IL-4-treatment (Figures 5A and 5B). In
addition, the treatment of immunized mice with GSK-J4 during
the early stage of the GC formation significantly decreased the
number of antigen-specific GC B cells (Figure 5C). Moreover,
small hairpin RNA (shRNA)-mediated knockdown of UTX in iGB
cells (Figures S5A and S5B) increased H3K27me3 at the Bcl6 en-
hancers and decreased the expression of Bcl6 after treatment
with IL-4 (Figures 5D and 5E). To assess the role of UTX in the
aKG-mediated GC formation in vivo, B cells transduced with
shControl or shUTX and cultured under low glucose conditions
with or without DMaKG were transferred into NP-CGG-immu-
nized B6 mice (Figure S5C). Supplementation with DMaKG
restored the GC formation of B cells transduced with shControl
but not of those with shUTX (Figure S5D). These data highlight
that active H3K27me3-demethylation mediated by UTX with
aKG is required forBcl6 upregulation and GCB cell development.
STAT6 Is Required for the Recruitment of UTX to theBcl6 Enhancers during GC B Cell DevelopmentSince the addition of DMaKG alone to iGB cells cultured without
IL-4 did not result in an increase in Bcl6 expression (Figure S6A),
general activation of UTX by aKG appears insufficient for the
Bcl6 induction. Thus, we next sought to clarify the mechanisms
by which the genome-wide epigenetic modifier UTX targets the
Bcl6 locus after the IL-4 stimulation. The IL-4-IL-4R axis is known
to activate transcription factors signal transducer and activator
of transcription 3 (STAT3), STAT5, and STAT6, and this was
the case for iGB cells (Figure 6A). shRNA-mediated knockdown
revealed that STAT6 but not STAT3 or STAT5 was responsible
for the upregulation of Bcl6 expression after IL-4 treatment (Fig-
ures 6B and S6B). Then, we assessed the effect of STAT6 knock-
down in vivo. We transduced in vivo-primed B1-8hi B cells with
the STAT6-knockdown vector in the absence of IL-4 in vitro
and then transferred them into B6 mice 1 day before immuniza-
tion with NP-CGG (Figure S6C). Consistent with an earlier finding
(Turqueti-Neves et al., 2014), the knockdown of STAT6 remark-
ably inhibited the formation of GC B cells (Figure 6C), indicating
Cell Reports 33, 108333, November 3, 2020 7
A B C D E
Figure 5. The H3K27me3-Specific Demethylase UTX Mediates Bcl6 Induction
(A and B) IgG1+ iGB cells were stimulated with IL-4 in the absence (�) or presence of GSK-J4.
(A) ChIP-qPCR analysis after 6 h of stimulation.
(B) qRT-PCR analysis after 1 day of stimulation.
(C) Immunized mice were injected with vehicle alone (�) or GSK-J4 (left, top). The numbers of NP+ GC B cells (right) were estimated by flow cytometric analysis
(left, bottom; the numbers indicate frequencies among NP+B220+CD138– cells).
(D and E) Analysis of iGB cells transduced with shControl or shUTX as in Figure S5A and stimulated with IL-4.
(D) ChIP-qPCR analysis after 6 h of stimulation.
(E) qRT-PCR analysis after 1 day of stimulation.
The data are means ± SDs of 3 technical replicates (A, D, and E) or 3 (B) or 6 (C) biological replicates. Each symbol represents a biologically independent sample
(B) or an individual mouse (C). The data are representative of 2 (A–E) independent experiments. p values were calculated by 2-tailed unpaired Student’s t test (B
and C). See also Figure S5.
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that STAT6-activating stimuli are important for GC B cell devel-
opment in vivo. We next assessed whether STAT6 is necessary
for the IL-4-mediated demethylation of the Bcl6 locus. The
knockdown of STAT6 increased H3K27me3 at regions including
the Bcl6 enhancers and decreased H3K27Ac at the enhancer
and the regions around the transcription start site, after IL-4
treatment (Figure 6D). As an exception, the knockdown of
STAT6 markedly increased H3K27me3 but did not diminish
H3K27Ac at positions �225, �10, and �5 kb, suggesting that
H3K27me3 demethylation of these regions does not directly
affect the transcriptional state of the chromatin.
Using published ChIP-seq data frommacrophages stimulated
with IL-4 (Czimmerer et al., 2018), we found that STAT6 binds to
Bcl6 enhancer 1 and 2 in addition to a known binding site in the
promoter region (Chevrier et al., 2017) (Figure S4A). Our ChIP-
qPCR analysis of iGB cells confirmed the STAT6 binding in the
same regions of the Bcl6 enhancers and promoter after IL-4
treatment (Figure 6E, top). Notably, UTX was also recruited to
the same regions of the enhancers that were bound by STAT6 af-
ter IL-4 treatment (Figure 6E, bottom). Co-immunoprecipitation
(coIP) analysis of iGB cells revealed a physical association of
STAT6 with UTX, increasing along with the IL-4 treatment time
course (Figure 6F). Furthermore, knock down of STAT6 reduced
the UTX binding to the Bcl6 enhancers (Figure 6G), suggesting a
functional association between STAT6 and UTX. Based on all of
these observations, we concluded that STAT6 recruits UTX to
the Bcl6 enhancers, where it demethylates H3K27me3 and tran-
scriptionally activates the chromatin at the enhancer and pro-
moter regions, thus activating the transcription of the Bcl6
gene during IL-4-mediated differentiation of GC B cells.
IL-4 Signaling Regulates the TCA Cycle Enzymes toAccumulate Intracellular aKGTo understand how IL-4 signaling results in the accumulation of
aKG, we assessed enzymatic activities of isocitrate dehydroge-
8 Cell Reports 33, 108333, November 3, 2020
nases (IDHs) and aKG dehydrogenase (aKGDH), the aKG-pro-
ducing and -consuming enzymes in the oxidative TCA cycle,
respectively (Figure 7A), in the mitochondrial fraction of GC B
cells and iGB cells. The activities of nicotinamide adenine dinu-
cleotide phosphate (NADP)+-dependent IDH2 and NAD+-depen-
dent IDH3 were higher in GC B cells, while the activity of aKGDH
was lower than in NB cells (Figure 7B). Similar trends were
observed in iGB cells treated with IL-4 as compared with those
treated with anti-IgG or untreated (Figure 7C). Since the
enhancement of the enzymatic activity of IDH2 was higher than
that of IDH3 in both GC B cells and IL-4-stimulated iGB cells,
we focused on IDH2. Knock down of IDH2 in IL-4-treated iGB
cells significantly decreased the amount of intracellular aKG
and the expression of Bcl6 (Figures 7D, 7E, and S7A). Accord-
ingly, IDH2-knockdown B cells developed less well into GC B
cells than control B cells in recipient mice after immunization
(Figure 7F).
To elucidate how IL-4 treatment downmodulates aKGDH
activity, we assessed the expression of its three subunits: E1 (ox-
oglutarate dehydrogenase [OGDH]), E2 (dihydrolipoamide
succinyltransferase [DLST]), and E3 (dihydrolipoamide dehydro-
genase [DLD]). We found that the level of DLST protein, but not
mRNA, was lower in GC B cells than in NB cells, and also in
iGB cells treated with IL-4 than those treated with anti-IgG or
left unstimulated (Figures 7G, 7H, and S7B–S7D), indicating
post-transcriptional regulation of DLST. The proteasomal inhibi-
tor MG-132 restored DLST protein level in the presence of IL-4,
whereas a lysosomal inhibitor bafilomycin A1 (BafA1) had no ef-
fect (Figure 7I). In addition, we found that DLST protein in iGB
cells was polyubiquitinated after treatment with IL-4, but not
with anti-IgG, as seen in the presence of MG-132 (Figure 7J).
Given the previous report that DLST is targeted by the E3 ubiq-
uitin ligase SIAH2 for proteasomal degradation (Habelhah et al.,
2004), we focused on the function of SIAH2. We found that, after
treatment of iGB cells with IL-4, SIAH2 was associated with
A
D
B C
E F
G
Figure 6. STAT6 Recruits UTX and Activates Transcription of the Bcl6 Locus
(A) Immunoblot analysis of iGB cells after treatment with IL-4 for the indicated times.
(B) Flow cytometric analysis of iGB cells transducedwith shControl or shSTAT as in Figure S5A and cultured with IL-4 for 1 day. Shown are representative plots of
GFP+IgG1+ cells.
(C) Analysis of spleen cells from mice day 7 post-immunization that had received B1-8hi B cells transduced with shControl or shSTAT6 as in Figure S6C. The
numbers of the transduced (GFP+) NP+ GC B cells (right) were estimated by flow cytometric analysis (left; the numbers indicate frequency among donor GC B
cells [CD45.1+NP+GL7+B220+CD138�CD38lo]).(D) ChIP-qPCR analysis at Bcl6 locus of iGB cells transduced with shControl or shSTAT6 and culture with IL-4 for 6 h.
(E) ChIP-qPCR analysis for STAT6 or UTX binding at Bcl6 locus of IgG1+ iGB cells treated with IL-4 or left untreated (�) for 3 h.
(F) Immunoblot detection of UTX and STAT6 in proteins immunoprecipitated (IP) with control IgG or anti-STAT6 Ab from whole-cell lysate (WCL) of iGB cells
cultured with IL-4 for the indicated times.
(G) ChIP-qPCR analysis for UTX binding at Bcl6 locus of iGB cells transduced with shControl or shSTAT6 and treated with IL-4 for 3 h.
Data are means ± SDs of 6 biological replicates (C) or 3 technical replicates (D, E, and G). Each symbol represents an individual mouse (C). The data are
representative of 2 (A, C, D, and G) or 3 (B, E, and F) independent experiments. p values were calculated by 2-tailed unpaired Student’s t test (C). See also
Figure S6.
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DLST (Figure 7K). Furthermore, knock down of SIAH2 in IL-4-
treated iGB cells resulted in an increase in DLST protein and a
decrease in the level of aKG and Bcl6 mRNA (Figures 7L–7N
and S7E). SIAH2 knockdown in B cells did not significantly affect
their development up to pre-GC B cells, but it did markedly
inhibit their differentiation to GC B cells in the recipient mice after
immunization (Figures S7F and S7O). Finally, the overexpression
of DLST in iGB cells suppressed Bcl6 expression in vitro and
their development into GC B cells in vivo (Figures S7G and
S7H). We concluded that IL-4 signaling modulates the amount
and/or activity of the aKG-regulating enzymes, resulting in the
accumulation of aKG, which drives Bcl6 expression and the
consequent GC B cell differentiation.
DISCUSSION
In this study, we have revealed that IL-4-mediated reprogram-
ming of TCA cycle metabolism in activated B cells drives the
accumulation of aKG that integrates STAT6-UTX-dependent
epigenetic activation of the Bcl6 locus, leading to the induction
of Bcl6 expression and GC B cell differentiation. In accord with
earlier findings (Cunningham et al., 2002; Gonzalez et al., 2018;
Cell Reports 33, 108333, November 3, 2020 9
A B C D E F
G H I J K
L M N O
Figure 7. IL-4 Signaling Controls the Activity of aKG-Regulating Enzymes
(A) Schema of a partial oxidative TCA cycle highlighting the enzymes regulating aKG production.
(B and C) Mitochondrial dehydrogenase activity in NB or GC B cells (B) or in IgG1+ iGB cells stimulated with either IL-4 or anti-IgG, or left unstimulated, for 6 h (C).
(D and E) Analysis of iGB cells transduced with shControl or shIDH2 as in Figure S5A and stimulated with IL-4.
(D) Intracellular aKG level after 6 h of stimulation.
(E) qRT-PCR analysis after 1 day of stimulation.
(F) Analysis of spleens from mice transferred with B1-8hi B cells transduced with shControl or shIDH2 as in Figure 6C. The data are presented as in Figure 6C.
(G andH) Immunoblot analysis for aKGDH subunits in NB or GCB cells (G), or in IgG1+ iGB cells cultured with either IL-4 or anti-IgG, or left unstimulated (�), for 6 h
(H).
(I) Immunoblot analysis for DLST in IgG1+ iGB cells cultured for 6 h with (+) or without (�) IL-4 in the absence (�) or presence of MG-132 or bafilomycin A1 (BafA1).
(J) Immunoblot analysis for ubiquitination (Ub) in proteins IP with anti-V5 Ab or control IgG from WCL of iGB cells transduced with DLST-V5 and cultured for 6 h
with IL-4, anti-IgG, or medium alone (�), and MG-132 (top). NS, nonspecific bands. Bottom: anti-V5 blot.
(K) Immunoblot detection of DLST in the proteins precipitated with anti-FLAG Ab from WCL (top), or in the WCL (bottom), of iGB cells transduced with FLAG-
SIAH2 and cultured as in (J). FLAG, anti-FLAG blot.
(L–N) iGB cells transduced with shControl or shSIAH2 were stimulated with IL-4.
(L) Immunoblot analysis after 6 h of stimulation.
(M) Intracellular aKG level after 6 h of stimulation.
(N) qRT-PCR analysis after 1 day of stimulation.
(O) Analysis of spleens frommice transferred with B1-8hi B cells transduced with shControl or shSIAH2 and immunized as in (F). The data are presented as in (F).
Data are means ± SDs of 3 technical replicates from 1 biological sample pooled from n = 3 (NB in B) or 20 (GC B in B), or 3 (C–E, M, and N) or 6 (F and O) biological
replicates. Each symbol represents a biological sample of triplicate culture (C), a biological sample of triplicate transductions (D, E, M, and N), or an individual
mouse (F and O). The data are representative of 2 (B–F and J–O) or 3 (G and H) independent experiments, or from 1 experiment (I). p values were calculated by 1-
way ANOVA with Tukey’s test (C) or 2-tailed unpaired Student’s t test (D–F and M–O). See also Figure S7.
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OPEN ACCESS
Turqueti-Neves et al., 2014), we demonstrated that the IL-4-
signaling axis is an important instructive signal for GC B cell dif-
ferentiation. We further revealed that IL-4 signaling is the key
inducer of Bcl6 and identified the detailed molecular mecha-
10 Cell Reports 33, 108333, November 3, 2020
nisms for Bcl6 induction. In B cells stimulated with IL-4 for 6 h,
the DJm was elevated and cellular metabolism was rapidly re-
programmed, especially in the TCA cycle, which resulted in the
accumulation of intracellular aKG that was required for the
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induction of Bcl6 expression. Under conditions of limited
glucose, supplementation with aKG was sufficient to induce
Bcl6 expression in vitro and GC B cell development in vivo.
aKG accumulation was mainly due to the following modulations
of TCA cycle enzymes: (1) decreased aKGDH activity through
the SIAH2-mediated degradation of DLST (Habelhah et al.,
2004) and (2) enhanced IDH2 activity by as yet unknown mech-
anisms. The elevatedDJm and aKG accumulation, as well as the
alterations in the activity of aKGDH and IDH2, were also
observed in ex vivo GC B cells, suggesting that the same mech-
anism forBcl6 expression ismaintained throughout theGCB cell
development process.
Despite the previous evidence for a crucial role of glutaminol-
ysis in producing aKG (Carey et al., 2015; Chisolm et al., 2017),
our data indicate that reprogramming TCA cycle regulation
mainly contributes to the accumulation of intracellular aKG in
IL-4-stimulated B cells. This is consistent with the recent report
that aKG-accumulation relies on mitochondrial oxidative meta-
bolism in primordial germ cells (Tischler et al., 2019). It was re-
ported that pharmacological inhibition of the ETC suppresses
pyruvate entry into the TCA cycle and activates the reductive
TCA cycle, a reverse reaction relative to the canonical oxidative
TCA cycle (Mullen et al., 2011). The reductive TCA cycle pro-
motes the conversion of aKG into citrate, providing growth-pro-
moting nutrients such as acetyl-CoA and lowering the aKG level
(Fendt et al., 2013). Consistently, we observed that ETC inhibi-
tion in IL-4-stimulated B cells suppressed aKG accumulation
and Bcl6 expression, further illustrating that the oxidative TCA
cycle is important for the aKG accumulation in differentiating B
cells. Ex vivo GC B cells also exhibited elevated DJm, and GC
B cell development was dependent on the mitochondrial oxida-
tive metabolism. These data strongly suggest that mitochondrial
oxidative metabolism plays a dominant role in GC B cell meta-
bolism as observed in IL-4-activated differentiating B cells. While
wewere completing this manuscript, another study reported that
GC B cells primarily usemitochondrial oxidative metabolism that
is mainly fueled with fatty acids (FAs), but minimally use glycol-
ysis (Weisel et al., 2020). This study mainly focused on estab-
lished GC B cells (at day 14 postimmunization) with in vivo inter-
vention starting from day 9; however, our data instead represent
an early phase of GC B cell development. They also showed that
early GC B cells (at day 8 postimmunization) do not significantly
rely on exogenous FAs, but peak (day 13) or late (day 23) GC B
cells do so. Thus, the fuels required for the mitochondrial oxida-
tive metabolism in GC B cells may differ in their developing
phase and maintenance phase.
We demonstrated that STAT6 is a key transcriptional activator
of Bcl6 expression and acts cooperatively with accumulated
aKG. After IL-4 treatment, STAT6 bound to the Bcl6 locus, espe-
cially at the upstream enhancers that have been reported to be
the GC B cell-specific super-enhancers responsible for Bcl6
expression (Bunting et al., 2016; Ryan et al., 2015). In NB cells,
the same regions were abundant in H3K27me3, a characteristic
of poised enhancers that cannot drive gene expression (Calo and
Wysocka, 2013). Once such H3K27me3 are demethylated and
acquire acetylation at the same residue (H3K27Ac), the poised
enhancer regions become activated (Calo and Wysocka, 2013;
Rada-Iglesias et al., 2011). In line with this, we observed that
the Bcl6 enhancer-bound STAT6 recruited UTX, an aKG-depen-
dent JmjC-histone demethylase, which in turn reduced
H3K27me3 and increased H3K27Ac in the enhancers and then
activated Bcl6 transcription. UTX has recently been reported to
associate with an H3K27 acetyltransferase, p300/CBP (Calo
and Wysocka, 2013; Wang et al., 2017), a known co-activator
of STAT6 (Gingras et al., 1999). We demonstrated a physical as-
sociation of STAT6 andUTX in the IL-4-stimulated B cells; thus, it
is possible that STAT6 interacts indirectly with UTX via p300/
CBP. In addition, UTX has been shown to associate with
mixed-lineage leukemia (MLL)3/4 (Piunti and Shilatifard, 2016),
methyltransferases that deposit the H3K4me1 enhancer mark,
and with the SWI/SNF chromatin remodeler complex (Miller
et al., 2010). Hence, we speculate that the IL-4-activated
STAT6-UTX axis may exert multiple-layered epigenetic modula-
tion at the super-enhancers in the Bcl6 locus. We propose a
model in which, during GCB cell differentiation, IL-4 signaling re-
programs TCA cycle metabolism to accumulate aKG, which in-
tegrates the epigenetic activation of the Bcl6 locus mediated
by the STAT6-UTX axis.
Considering our data demonstrating that (1) GC B cells accu-
mulated aKG, (2) they displayed a global decrease in the
H3K27me3 mark, and (3) their development was dependent on
H3K27me3-demethylase activity, we propose that the aKG-
dependent demethylation of H3K27me3 actively occurs in GC B
cells. H3K27me3 has been considered to be dynamically
controlled, which allows genes to be switched on and off during
differentiation. For example, naive ESCs display aKG-accumula-
tion with a global decrease in H3K27me3 rendered by the aKG-
dependent demethylation process, whereas more differentiated
ESCs gain H3K27me3 in genes involved in cell fate determination,
concomitant with a decrease in intracellular aKG levels (Carey
et al., 2015; Hawkins et al., 2010; Zhu et al., 2013). By analogy,
we speculate that accumulated aKG in GC B cells may support
H3K27me3-demethylation, by which actively dividing GC B cells
may inherit the GC phenotype andmaintain the plasticity to differ-
entiate into memory B cells or long-lived PCs. In contrast to this
scenario, a histone methyltransferase enhancer of zeste homolog
2 (EZH2)-mediated deposition of H3K27me3 has been reported to
be required for the development ofGCBcells by inhibiting cell-cy-
cle arrest (Beguelin et al., 2013; Caganova et al., 2013). This
apparent discrepancy may be explained as follows: domains tar-
geted by H3K27me3-demethylase and those by H3K27me3-
methyltransferase do not completely overlap in GC B cells, as a
previous report showed that more than half of the genes activated
by UTX are not activated by the loss of EZH2 in multiple myeloma
cells (Ezponda et al., 2017).
In line with their involvement in GC development (Kopf et al.,
1998; Linterman et al., 2010; Turqueti-Neves et al., 2014; Zotos
et al., 2010), IL-6, IL-13, and IL-21 also upregulated Bcl6 expres-
sion in vitro, albeit modestly as compared to IL-4. The fact that
IL-6 and IL-21 do not use STAT6 for signaling implies STAT6-
independent mechanisms for Bcl6 induction. It was reported
that the IL-4/IL-13-STAT6 axiswas required for GC formation after
helminth infection or immunization with ovalbumin in alum or
sheep red blood cells (SRBCs), but not after infection with lym-
phocytic choriomeningitis virus (LCMV) or murine cytomegalo-
virus (MCMV) (Turqueti-Neves et al., 2014). Other reports
Cell Reports 33, 108333, November 3, 2020 11
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OPEN ACCESS
demonstrated that STAT6-deficient B cells exhibited almost
normal GC responses in mixed bone marrow chimeric mice
when immunized with SRBC, but a markedly reduced GC
response after influenza virus infection; functional redundancy of
STAT6 and IL-21 signaling was apparent in both (Chevrier et al.,
2017). In line with our data, it was reported that STAT6 contributes
to the expansion of Bcl6hi GC B cells beyond the pre-GC stage,
whereas IL-21 is required for pre-GC B cell expansion, in mice
immunized with NP-ovalbumin in alum (Gonzalez et al., 2018).
Although differences in experimental settings may cause some
discrepancy, these results suggest that the extent of the contribu-
tion of IL-4-STAT6 axis to Bcl6 induction and GC formation in vivo
may vary depending on different antigens, adjuvants, immuniza-
tion protocols, and so on, and can be induced by IL-4-STAT6-in-
dependent signaling pathways in some situations. Clarifying such
alternative pathways will provide deeper insight into the mecha-
nisms regulating GC B cell development.
Finally, given our results revealing that metabolic reprogram-
ing is a crucial factor regulating the expression of a key transcrip-
tion factor and GC B cell differentiation, one may need to
consider such dysregulated B cell metabolism, possibly caused
in a cell-intrinsic manner and/or by some environmental factors
(e.g., nutrients), as a component of the pathogenesis of immuno-
logical disorders and lymphomagenesis.
STAR+METHODS
Detailed methods are provided in the online version of this paper
and include the following:
d KEY RESOURCES TABLE
d RESOURCE AVAILABILITY
12
B Lead Contact
B Materials Availability
B Data and Code Availability
d EXPERIMENTAL MODEL AND SUBJECT DETAILS
B Mice
B iGB cell culture
d METHOD DETAILS
B Immunization and in vivo treatments
B Ex vivo cell purification
B Flow cytometry
B BrdU incorporation assay
B Immunoblotting and immunoprecipitation
B RT-PCR, qPCR
B Dehydrogenase activity assay
B Lactate production assay
B Plasmid constructions
B Retroviral Transduction
B Metabolomics
B aKG measurement
B Chromatin immunoprecipitation (ChIP) analysis
d QUANTIFICATION AND STATISTICAL ANALYSIS
SUPPLEMENTAL INFORMATION
Supplemental Information can be found online at https://doi.org/10.1016/j.
celrep.2020.108333.
Cell Reports 33, 108333, November 3, 2020
ACKNOWLEDGMENTS
We thankM. Nussenzweig (Rockefeller University) and T. Kurosaki (OsakaUni-
versity) for B1-8hi mice; N. Yakushiji-Kaminatsui (RIKEN) for technical advice
and critical comments; H. Ebiko and H. Hasegawa (RIBS) for technical assis-
tance; T. Koike (RIBS) for plasmid constructs and suggestions; and P. Burrows
for critical reading of the manuscript. This work was supported by the Japan
Society for the Promotion of Science KAKENHI Grant-in-Aid for Young Scien-
tists (A) (17H05072) (to K.H.) and Grant-in-Aid for Challenging Exploratory
Research (16K15295) (to D.K.), and by the Kanae Foundation, the Inamori
Foundation, the Naito Foundation, and the Nakajima Foundation (all to K.H.).
AUTHOR CONTRIBUTIONS
K.H. conceived and supervised the project, designed and performed experi-
ments, analyzed the data, andwrote themanuscript. S.F. designed, performed
experiments, edited the manuscript, and originally suggested that metabolism
is a fate-determining factor of B cells. D.K. supervised the project and wrote
the manuscript.
DECLARATION OF INTERESTS
The authors declare no competing interests.
Received: April 29, 2020
Revised: July 8, 2020
Accepted: October 8, 2020
Published: November 3, 2020
REFERENCES
Basso, K., and Dalla-Favera, R. (2012). Roles of BCL6 in normal and trans-
formed germinal center B cells. Immunol. Rev. 247, 172–183.
Beguelin, W., Popovic, R., Teater, M., Jiang, Y., Bunting, K.L., Rosen, M.,
Shen, H., Yang, S.N., Wang, L., Ezponda, T., et al. (2013). EZH2 is required
for germinal center formation and somatic EZH2 mutations promote lymphoid
transformation. Cancer Cell 23, 677–692.
Braz~ao, T.F., Johnson, J.S., M€uller, J., Heger, A., Ponting, C.P., and Tybule-
wicz, V.L.J. (2016). Long noncoding RNAs in B-cell development and activa-
tion. Blood 128, e10–e19.
Bunting, K.L., Soong, T.D., Singh, R., Jiang, Y., Beguelin, W., Poloway, D.W.,
Swed, B.L., Hatzi, K., Reisacher,W., Teater,M., et al. (2016). Multi-tiered Reor-
ganization of the Genome during B Cell Affinity Maturation Anchored by a
Germinal Center-Specific Locus Control Region. Immunity 45, 497–512.
Caganova, M., Carrisi, C., Varano, G., Mainoldi, F., Zanardi, F., Germain, P.-L.,
George, L., Alberghini, F., Ferrarini, L., Talukder, A.K., et al. (2013). Germinal
center dysregulation by histone methyltransferase EZH2 promotes lympho-
magenesis. J. Clin. Invest. 123, 5009–5022.
Calado, D.P., Sasaki, Y., Godinho, S.A., Pellerin, A., Kochert, K., Sleckman,
B.P., de Alboran, I.M., Janz, M., Rodig, S., and Rajewsky, K. (2012). The
cell-cycle regulator c-Myc is essential for the formation and maintenance of
germinal centers. Nat. Immunol. 13, 1092–1100.
Calo, E., and Wysocka, J. (2013). Modification of enhancer chromatin: what,
how, and why? Mol. Cell 49, 825–837.
Carey, B.W., Finley, L.W.S., Cross, J.R., Allis, C.D., and Thompson, C.B.
(2015). Intracellular a-ketoglutarate maintains the pluripotency of embryonic
stem cells. Nature 518, 413–416.
Chapuy, B., McKeown, M.R., Lin, C.Y., Monti, S., Roemer, M.G.M., Qi, J.,
Rahl, P.B., Sun, H.H., Yeda, K.T., Doench, J.G., et al. (2013). Discovery and
characterization of super-enhancer-associated dependencies in diffuse large
B cell lymphoma. Cancer Cell 24, 777–790.
Chevrier, S., Kratina, T., Emslie, D., Tarlinton, D.M., and Corcoran, L.M. (2017).
IL4 and IL21 cooperate to induce the high Bcl6 protein level required for
germinal center formation. Immunol. Cell Biol. 95, 925–932.
Articlell
OPEN ACCESS
Chisolm, D.A., Savic, D., Moore, A.J., Ballesteros-Tato, A., Leon, B., Cross-
man, D.K., Murre, C., Myers, R.M., and Weinmann, A.S. (2017). CCCTC-Bind-
ing Factor Translates Interleukin 2- and a-Ketoglutarate-Sensitive Metabolic
Changes in T Cells into Context-Dependent Gene Programs. Immunity 47,
251–267.e7.
Cunningham, A.F., Fallon, P.G., Khan, M., Vacheron, S., Acha-Orbea, H., Ma-
cLennan, I.C.M., McKenzie, A.N., and Toellner, K.-M. (2002). Th2 activities
induced during virgin T cell priming in the absence of IL-4, IL-13, and B cells.
J. Immunol. 169, 2900–2906.
Czimmerer, Z., Daniel, B., Horvath, A., R€uckerl, D., Nagy, G., Kiss, M., Pelo-
quin, M., Budai, M.M., Cuaranta-Monroy, I., Simandi, Z., et al. (2018). The
Transcription Factor STAT6 Mediates Direct Repression of Inflammatory En-
hancers and Limits Activation of Alternatively Polarized Macrophages. Immu-
nity 48, 75–90.e6.
Dominguez-Sola, D., Victora, G.D., Ying, C.Y., Phan, R.T., Saito, M., Nussenz-
weig, M.C., and Dalla-Favera, R. (2012). The proto-oncogene MYC is required
for selection in the germinal center and cyclic reentry. Nat. Immunol. 13, 1083–
1091.
Ersching, J., Efeyan, A., Mesin, L., Jacobsen, J.T., Pasqual, G., Grabiner, B.C.,
Dominguez-Sola, D., Sabatini, D.M., and Victora, G.D. (2017). Germinal Center
Selection and Affinity Maturation Require Dynamic Regulation of mTORC1 Ki-
nase. Immunity 46, 1045–1058.e6.
Ezponda, T., Dupere-Richer, D., Will, C.M., Small, E.C., Varghese, N., Patel, T.,
Nabet, B., Popovic, R., Oyer, J., Bulic, M., et al. (2017). UTX/KDM6A Loss En-
hances the Malignant Phenotype of Multiple Myeloma and Sensitizes Cells to
EZH2 inhibition. Cell Rep. 21, 628–640.
Fendt, S.-M., Bell, E.L., Keibler, M.A., Olenchock, B.A., Mayers, J.R., Wasy-
lenko, T.M., Vokes, N.I., Guarente, L., Vander Heiden, M.G., and Stephano-
poulos, G. (2013). Reductive glutamine metabolism is a function of the a-keto-
glutarate to citrate ratio in cells. Nat. Commun. 4, 2236.
Finkelman, F.D., Madden, K.B., Morris, S.C., Holmes, J.M., Boiani, N., Katona,
I.M., andMaliszewski, C.R. (1993). Anti-cytokine antibodies as carrier proteins.
Prolongation of in vivo effects of exogenous cytokines by injection of cytokine-
anti-cytokine antibody complexes. J. Immunol. 151, 1235–1244.
Gingras, S., Simard, J., Groner, B., and Pfitzner, E. (1999). p300/CBP is
required for transcriptional induction by interleukin-4 and interacts with
Stat6. Nucleic Acids Res. 27, 2722–2729.
Gonzalez, D.G., Cote, C.M., Patel, J.R., Smith, C.B., Zhang, Y., Nickerson,
K.M., Zhang, T., Kerfoot, S.M., and Haberman, A.M. (2018). Nonredundant
Roles of IL-21 and IL-4 in the Phased Initiation of Germinal Center B Cells
and Subsequent Self-Renewal Transitions. J. Immunol. 201, 3569–3579.
Habelhah, H., Laine, A., Erdjument-Bromage, H., Tempst, P., Gershwin, M.E.,
Bowtell, D.D.L., and Ronai, Z. (2004). Regulation of 2-oxoglutarate (a-ketoglu-
tarate) dehydrogenase stability by the RING finger ubiquitin ligase Siah. J. Biol.
Chem. 279, 53782–53788.
Haniuda, K., Fukao, S., Kodama, T., Hasegawa, H., and Kitamura, D. (2016).
Autonomous membrane IgE signaling prevents IgE-memory formation. Nat.
Immunol. 17, 1109–1117.
Hawkins, R.D., Hon, G.C., Lee, L.K., Ngo, Q., Lister, R., Pelizzola, M., Edsall,
L.E., Kuan, S., Luu, Y., Klugman, S., et al. (2010). Distinct epigenomic land-
scapes of pluripotent and lineage-committed human cells. Cell Stem Cell 6,
479–491.
Jellusova, J., Cato, M.H., Apgar, J.R., Ramezani-Rad, P., Leung, C.R., Chen,
C., Richardson, A.D., Conner, E.M., Benschop, R.J.,Woodgett, J.R., andRick-
ert, R.C. (2017). Gsk3 is a metabolic checkpoint regulator in B cells. Nat. Im-
munol. 18, 303–312.
Koike, T., Harada, K., Horiuchi, S., and Kitamura, D. (2019). The quantity of
CD40 signaling determines the differentiation of B cells into functionally
distinct memory cell subsets. eLife 8, e44245.
Kopf, M., Herren, S., Wiles, M.V., Pepys, M.B., and Kosco-Vilbois, M.H. (1998).
Interleukin 6 influences germinal center development and antibody production
via a contribution of C3 complement component. J. Exp. Med. 188, 1895–
1906.
Kruidenier, L., Chung, C.W., Cheng, Z., Liddle, J., Che, K., Joberty, G., Bant-
scheff, M., Bountra, C., Bridges, A., Diallo, H., et al. (2012). A selective jumonji
H3K27 demethylase inhibitor modulates the proinflammatory macrophage
response. Nature 488, 404–408.
Linterman, M.A., Beaton, L., Yu, D., Ramiscal, R.R., Srivastava, M., Hogan,
J.J., Verma, N.K., Smyth, M.J., Rigby, R.J., and Vinuesa, C.G. (2010). IL-21
acts directly on B cells to regulate Bcl-6 expression and germinal center re-
sponses. J. Exp. Med. 207, 353–363.
Meng, F.L., Du, Z., Federation, A., Hu, J., Wang, Q., Kieffer-Kwon, K.R.,
Meyers, R.M., Amor, C., Wasserman, C.R., Neuberg, D., et al. (2014). Conver-
gent transcription at intragenic super-enhancers targets AID-initiated genomic
instability. Cell 159, 1538–1548.
Miller, S.A., Mohn, S.E., andWeinmann, A.S. (2010). Jmjd3 and UTX play a de-
methylase-independent role in chromatin remodeling to regulate T-box family
member-dependent gene expression. Mol. Cell 40, 594–605.
Mullen, A.R., Wheaton, W.W., Jin, E.S., Chen, P.H., Sullivan, L.B., Cheng, T.,
Yang, Y., Linehan, W.M., Chandel, N.S., and DeBerardinis, R.J. (2011). Reduc-
tive carboxylation supports growth in tumour cells with defective mitochon-
dria. Nature 481, 385–388.
Nojima, T., Haniuda, K., Moutai, T., Matsudaira, M., Mizokawa, S., Shiratori, I.,
Azuma, T., and Kitamura, D. (2011). In-vitro derived germinal centre B cells
differentially generate memory B or plasma cells in vivo. Nat. Commun. 2, 465.
Pearce, E.L., Poffenberger, M.C., Chang, C.-H., and Jones, R.G. (2013).
Fueling immunity: insights into metabolism and lymphocyte function. Science
342, 1242454.
Peng, M., Yin, N., Chhangawala, S., Xu, K., Leslie, C.S., and Li, M.O. (2016).
Aerobic glycolysis promotes T helper 1 cell differentiation through an epige-
netic mechanism. Science 354, 481–484.
Piunti, A., and Shilatifard, A. (2016). Epigenetic balance of gene expression by
Polycomb and COMPASS families. Science 352, aad9780.
Rada-Iglesias, A., Bajpai, R., Swigut, T., Brugmann, S.A., Flynn, R.A., and Wy-
socka, J. (2011). A unique chromatin signature uncovers early developmental
enhancers in humans. Nature 470, 279–283.
Raisner, R., Kharbanda, S., Jin, L., Jeng, E., Chan, E., Merchant, M., Haverty,
P.M., Bainer, R., Cheung, T., Arnott, D., et al. (2018). Enhancer Activity Re-
quires CBP/P300 Bromodomain-Dependent Histone H3K27 Acetylation. Cell
Rep. 24, 1722–1729.
Ryan, R.J.H., Drier, Y., Whitton, H., Cotton, M.J., Kaur, J., Issner, R., Gillespie,
S., Epstein, C.B., Nardi, V., Sohani, A.R., et al. (2015). Detection of enhancer-
associated rearrangements reveals mechanisms of oncogene dysregulation in
B-cell lymphoma. Cancer Discov. 5, 1058–1071.
Saito, M., Gao, J., Basso, K., Kitagawa, Y., Smith, P.M., Bhagat, G., Pernis, A.,
Pasqualucci, L., and Dalla-Favera, R. (2007). A signaling pathway mediating
downregulation of BCL6 in germinal center B cells is blocked by BCL6 gene
alterations in B cell lymphoma. Cancer Cell 12, 280–292.
Shih, T.A.Y., Roederer, M., and Nussenzweig, M.C. (2002). Role of antigen re-
ceptor affinity in T cell-independent antibody responses in vivo. Nat. Immunol.
3, 399–406.
Shyh-Chang, N., Locasale, J.W., Lyssiotis, C.A., Zheng, Y., Teo, R.Y., Ratana-
sirintrawoot, S., Zhang, J., Onder, T., Unternaehrer, J.J., Zhu, H., et al. (2013).
Influence of threonine metabolism on S-adenosylmethionine and histone
methylation. Science 339, 222–226.
Soga, T., and Heiger, D.N. (2000). Amino acid analysis by capillary electropho-
resis electrospray ionization mass spectrometry. Anal. Chem. 72, 1236–1241.
Soga, T., Ueno, Y., Naraoka, H., Ohashi, Y., Tomita, M., and Nishioka, T.
(2002). Simultaneous determination of anionic intermediates for Bacillus sub-
tilis metabolic pathways by capillary electrophoresis electrospray ionization
mass spectrometry. Anal. Chem. 74, 2233–2239.
Soga, T., Ohashi, Y., Ueno, Y., Naraoka, H., Tomita, M., and Nishioka, T.
(2003). Quantitative metabolome analysis using capillary electrophoresis
mass spectrometry. J. Proteome Res. 2, 488–494.
Cell Reports 33, 108333, November 3, 2020 13
Articlell
OPEN ACCESS
Sun, R.C., and Denko, N.C. (2014). Hypoxic regulation of glutamine meta-
bolism through HIF1 and SIAH2 supports lipid synthesis that is necessary
for tumor growth. Cell Metab. 19, 285–292.
Tischler, J., Gruhn, W.H., Reid, J., Allgeyer, E., Buettner, F., Marr, C., Theis, F.,
Simons, B.D., Wernisch, L., and Surani, M.A. (2019). Metabolic regulation of
pluripotency and germ cell fate through a-ketoglutarate. EMBO J. 38, e99518.
Turqueti-Neves, A., Otte, M., Prazeres da Costa, O., Hopken, U.E., Lipp, M.,
Buch, T., and Voehringer, D. (2014). B-cell-intrinsic STAT6 signaling controls
germinal center formation. Eur. J. Immunol. 44, 2130–2138.
Vander Heiden, M.G., Cantley, L.C., and Thompson, C.B. (2009). Understand-
ing the Warburg effect: the metabolic requirements of cell proliferation. Sci-
ence 324, 1029–1033.
Vian, L., Pekowska, A., Rao, S.S.P., Kieffer-Kwon, K.R., Jung, S., Baranello, L.,
Huang, S.C., El Khattabi, L., Dose, M., Pruett, N., et al. (2018). The Energetics
and Physiological Impact of Cohesin Extrusion. Cell 173, 1165–1178.e20.
Victora, G.D., and Nussenzweig, M.C. (2012). Germinal centers. Annu. Rev.
Immunol. 30, 429–457.
Wang, S.P., Tang, Z., Chen, C.W., Shimada, M., Koche, R.P., Wang, L.H., Na-
kadai, T., Chramiec, A., Krivtsov, A.V., Armstrong, S.A., and Roeder, R.G.
(2017). A UTX-MLL4-p300 Transcriptional Regulatory Network Coordinately
Shapes Active Enhancer Landscapes for Eliciting Transcription. Mol. Cell 67,
308–321.e6.
Weisel, F.J., Mullett, S.J., Elsner, R.A., Menk, A.V., Trivedi, N., Luo, W., Wiken-
heiser, D., Hawse, W.F., Chikina, M., Smita, S., et al. (2020). Germinal center B
14 Cell Reports 33, 108333, November 3, 2020
cells selectively oxidize fatty acids for energy while conducting minimal glycol-
ysis. Nat. Immunol. 21, 331–342.
Woodland, R.T., Fox, C.J., Schmidt, M.R., Hammerman, P.S., Opferman, J.T.,
Korsmeyer, S.J., Hilbert, D.M., and Thompson, C.B. (2008). Multiple signaling
pathways promote B lymphocyte stimulator dependent B-cell growth and sur-
vival. Blood 111, 750–760.
Yakushiji-Kaminatsui, N., Kondo, T., Hironaka, K.-I., Sharif, J., Endo, T.A., Na-
kayama, M., Masui, O., Koseki, Y., Kondo, K., Ohara, O., et al. (2018). Variant
PRC1 competes with retinoic acid-related signals to repress Meis2 in the
mouse distal forelimb bud. Development 145, dev166348.
Zhang, T.T., Gonzalez, D.G., Cote, C.M., Kerfoot, S.M., Deng, S., Cheng, Y.,
Magari, M., and Haberman, A.M. (2017). Germinal center B cell development
has distinctly regulated stages completed by disengagement from T cell
help. eLife 6, e19552.
Zhu, J., Adli, M., Zou, J.Y., Verstappen, G., Coyne, M., Zhang, X., Durham, T.,
Miri, M., Deshpande, V., De Jager, P.L., et al. (2013). Genome-wide chromatin
state transitions associated with developmental and environmental cues. Cell
152, 642–654.
Zotos, D., Coquet, J.M., Zhang, Y., Light, A., D’Costa, K., Kallies, A., Corcoran,
L.M., Godfrey, D.I., Toellner, K.-M., Smyth, M.J., et al. (2010). IL-21 regulates
germinal center B cell differentiation and proliferation through a B cell-intrinsic
mechanism. J. Exp. Med. 207, 365–378.
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STAR+METHODS
KEY RESOURCES TABLE
REAGENT or RESOURCE SOURCE IDENTIFIER
Antibodies
Biotin anti-mouse IgM Biolegend Cat# 406504; RRID: AB_315054
PE anti-mouse IgD Biolegend Cat# 405706; RRID: AB_315028
PerCP-Cy5.5 anti-mouse IgD Biolegend Cat# 405710; RRID: AB_1575113
FITC anti-mouse IgG1 BD Biosciences Cat# 553443; RRID: AB_394862
BV421 anti-mouse IgG1 BD Biosciences Cat# 562580; RRID: AB_2737664
APC anti-mouse IgG1 BD Biosciences Cat# 560089; RRID: AB_1645625
PE anti-mouse IgE Biolegend Cat# 406908; RRID: AB_493290
Biotin anti-mouse IgE Biolegend Cat# 406904; RRID: AB_315075
PE anti-mouse CD4 Biolegend Cat# 100512; RRID: AB_312715
Biotin anti-mouse CD4 Biolegend Cat# 100404; RRID: AB_312689
Biotin anti-mouse CD8 Biolegend Cat# 100704; RRID: AB_312743
Purified anti-mouse CD16/32 BD Biosciences Cat# 553142; RRID: AB_394657
PE-Cy7 anti-mouse CD19 Biolegend Cat# 115520; RRID: AB_313655
APC-Cy7 anti-mouse CD19 Biolegend Cat# 115530; RRID: AB_830707
PE anti-mouse CD38 Biolegend Cat# 102708; RRID: AB_312929
PE-Cy7 anti-mouse CD38 Biolegend Cat# 102718; RRID: AB_2275531
Biotin anti-mouse CD43 Biolegend Cat# 553269; RRID: AB_2255226
FITC anti-mouse CD45.1 Biolegend Cat# 110706; RRID: AB_313495
BV421 anti-mouse CD45.1 Biolegend Cat# 110732; RRID: AB_2562563
Biotin anti-mouse CD49b Biolegend Cat# 108904; RRID: AB_313411
PE anti-mouse CD138 Biolegend Cat# 142504; RRID: AB_10916119
PE-Cy7 anti-mouse CD138 Biolegend Cat# 142514; RRID: AB_2562198
BV421 anti-mouse CD138 Biolegend Cat# 142508; RRID: AB_11203544
Biotin anti-mouse CXCR5 Biolegend Cat# 145510; RRID: AB_2562126
PE-Cy7 anti-mouse B220 Biolegend Cat# 103222; RRID: AB_313005
APC-Cy7 anti-mouse B220 Biolegend Cat# 103224; RRID: AB_313007
APC anti-human/mouse Bcl6 Biolegend Cat# 358506; RRID: AB_2562472
Alexa Fluor 647 anti-BrdU Thermo Fisher Scientific Cat# B35140; RRID: AB_2536440
FITC anti-mouse/human GL7 Biolegend Cat# 144604; RRID: AB_2561697
BV421 anti-mouse/human GL7 BD Biosciences Cat# 562967; RRID: AB_2737922
Alexa Fluor 647 anti-mouse/human GL7 Biolegend Cat# 144606; RRID: AB_2562185
Biotin anti-mouse H-2Kd Biolegend Cat# 116604; RRID: AB_313739
PE anti-IRF4 eBiosciences Cat# 12-9858-82; RRID: AB_10852721
PE-Cy7 anti-mouse PD-1 Biolegend Cat# 109110; RRID: AB_572017
BV510 anti-mouse TER119 Biolegend Cat# 116237; RRID: AB_2561661
Biotin anti-mouse TER119 Biolegend Cat# 116204; RRID: AB_313705
HRP anti-goat IgG Jackson ImmunoResearch Cat# 805-035-180; RRID: AB_2340874
HRP anti-rabbit IgG Jackson ImmunoResearch Cat# 711-035-152; RRID: AB_10015282
HRP anti-mouse kappa SouthernBiotech Cat# 1050-05; RRID: AB_2650508
Anti-mouse IgG F(ab’)2 Jackson ImmunoResearch Cat# 115-006-071; RRID: AB_2338472
Anti-actin Santa Cruz Biotechnology Cat# sc-1616; RRID: AB_630836
Anti-mouse CD40 BioXCell Cat# BE0016-2; RRID: AB_1107647
Anti-DLD Bethyl Laboratories Cat# A304-733A; RRID: AB_2620928
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Continued
REAGENT or RESOURCE SOURCE IDENTIFIER
Anti-DLST Cell Signaling Technology Cat# 5556S; RRID: AB_10695157
Anti-FLAG-tag (M2) Sigma Cat# F3165; RRID: AB_259529
Anti-Histone H3 Cell Signaling Technology Cat# 4499S; RRID: AB_10544537
Anti-H3K4me3 Active Motif Cat# 39915; RRID: AB_2687512
Anti-H3K9me3 Cell Signaling Technology Cat# 13969S; RRID: AB_2798355
Anti-H3K27me3 Cell Signaling Technology Cat# 9733S; RRID: AB_2616029
Anti-H3K27Ac Cell Signaling Technology Cat# 8173S; RRID: AB_10949503
Anti-mouse IL-4 BioXCell Cat# BE0045; RRID: AB_1107707
Anti-OGDH Cell Signaling Technology Cat# 26865S; RRID: AB_2737585
Anti-PDH-E1a Cell Signaling Technology Cat# 3205S; RRID: AB_2162926
Anti-phospho-PDH-E1a (S293) Calbiochem Cat# AP1062; RRID: AB_10616069
Anti-STAT3 Santa Cruz Biotechnology Cat# sc-482; RRID: AB_632440
Anti-phospho-STAT3 (Y705) Cell Signaling Technology Cat# 9145S; RRID: AB_2491009
Anti-STAT5 Cell Signaling Technology Cat# 94205S; RRID: AB_2737403
Anti-phospho-STAT5 (Y694) Cell Signaling Technology Cat# 4322S; RRID: AB_10544692
Anti-STAT6 Santa Cruz Biotechnology Cat# sc-981; RRID: AB_632450
Anti-phospho-STAT6 (Y641) Cell Signaling Technology Cat# 56554S; RRID: AB_2799514
Anti-Tubulin Sigma Cat# T9026; RRID: AB_477593
Anti-UTX Cell Signaling Technology Cat# 33510S; RRID: AB_2721244
Anti-V5-tag Thermo Fisher Cat# R960-25; RRID: AB_2556564
Rabbit IgG Cell Signaling Technology Cat# 3900S; RRID: AB_1550038
Rabbit IgG Jackson ImmunoResearch Cat# 011-000-003; RRID: AB_2337118
Chemicals, Peptides, and Recombinant Proteins
Fixable Viability Dye eFluor 506 Thermo Fisher Scientific Cat# 65-0866-18
Recombinant murine IL-1a PeproTech Cat# 211-11A
Recombinant murine IL-1b PeproTech Cat# 211-11B
Recombinant murine IL-2 PeproTech Cat# 212-12
Recombinant murine IL-3 PeproTech Cat# 213-13
Recombinant murine IL-4 PeproTech Cat# 214-14
Recombinant murine IL-5 PeproTech Cat# 215-15
Recombinant murine IL-6 PeproTech Cat# 216-16
Recombinant murine IL-7 PeproTech Cat# 217-17
Recombinant murine IL-9 PeproTech Cat# 219-19
Recombinant murine IL-10 PeproTech Cat# 210-10
Recombinant murine IL-12 Biolegend Cat# 210-12
Recombinant murine IL-13 PeproTech Cat# 210-13
Recombinant murine IL-15 PeproTech Cat# 210-15
Recombinant murine IL-17A PeproTech Cat# 210-17
Recombinant murine IL-17F PeproTech Cat# 210-17F
Recombinant murine IL-21 PeproTech Cat# 210-21
Recombinant mouse IL-23 Biolegend Cat# 589002
Recombinant mouse IL-27 Biolegend Cat# 577402
Recombinant murine IL-28A (IFNl2) PeproTech Cat# 250-33
Recombinant murine IL-33 PeproTech Cat# 210-33
Recombinant mouse IFNa Biolegend Cat# 752802
Recombinant murine IFNg PeproTech Cat# 315-05
Recombinant human TGFb1 PeproTech Cat# 100-21
Recombinant SCF PeproTech Cat# 250-03
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Continued
REAGENT or RESOURCE SOURCE IDENTIFIER
Recombinant murine GM-CSF PeproTech Cat# 315-03
SYBR Green qPCR Master Mix Cat#
Tetramethylrhodamine, Methyl Ester,
Perchlorate (TMRM)
Thermo Fisher Scientific Cat# T668
MitoTracker Deep Red FM Thermo Fisher Scientific Cat# M22426
MitoSOX Red Thermo Fisher Scientific Cat# M36008
2-NBDG Thermo Fisher Scientific Cat# N13195
Oligomycin A Sigma Cat# 75351
5-Bromo-20-deoxyuridine (BrdU) Sigma Cat# B5002
Dimethyl a-ketoglutarate (DMaKG) Sigma Cat# 349631
Diethyl Succinate (DE-Suc) WAKO Cat# 056-03922
Sheep red blood cell (SRBC) Nippon Bio-supp. Center N/A
Internal standards for metabolomics Human Metabolome Technologies Cat# H3304-1002
2-isopropylmalic acid Sigma Cat# 333115
Methoxylamine hydrochloride MP Biomedicals Cat# 155405
N-methyl-N-trimethylsilyl-
trifluoroacetamide
GL Science Cat# 1022-11060
Formaldehyde Wako Cat# 064-00406
DNase I Sigma Cat# D5025
RNase A Sigma Cat# R6513
Proteinase K Merck Cat# 1.24568.0100
GSK-J4 Sigma Cat# SML0701
PEI Max (Mw 40,000) Polysciences Cat# 24765-1
NP-Osu Biosearch Technologies Cat# N-1010
NP14-BSA-Alexa Fluor 647 (Haniuda et al., 2016) N/A
NP14-BSA-Biotin (Haniuda et al., 2016) N/A
NP34-CGG (Haniuda et al., 2016) N/A
NP53-Ficoll Biosearch Technologies Cat# F-1420
DOTAP Liposomal Transfection Reagent Sigma Cat# 11202375001
Streptavidin-BV 421 Biolegend Cat# 405225
Streptavidin-PE-Cy7 Biolegend Cat# 405206
Streptavidin Particle Plus DM BD Biosciences Cat# 557812
Anti-FITC microbeads Miltenyi Biotec Cat# 130-048-701
Anti-PE microbeads Miltenyi Biotec Cat# 130-048-801
Dynabead Protein G Thermo Fisher Scientific Cat# 10004D
Protein G Sepharose 4 Fast Flow GE Healthcare Cat# 17061801
Anti-FLAG M2 Affinity Gel Sigma Cat# A2220
Anti-V5 Agarose Affinity Gel Sigma Cat# A7345-1ML
Mouse IgG�Agarose Sigma Cat# A0919
TRI Reagent Sigma Cat# T9424
Oligo(dT)20 Primer Thermo Fisher Scientific Cat# 18418020
Rotenone Sigma Cat# R8875
Nitro Blue Tetrazolium Chloride WAKO Cat# 148-01996
Phenazine methosulfate WAKO Cat# 166-09211
MG-132 WAKO Cat# 135-18453
Bafilomycin A1 Abcam Cat# ab120497
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Continued
REAGENT or RESOURCE SOURCE IDENTIFIER
Critical Commercial Assays
Foxp3/Transcription Factor Staining Buffer
Set
Thermo Fisher Scientific Cat# 00-5523-00
Fixation/Permeabilization Solution Kit BD Biosciences Cat# 554714
Glycolysis Cell-Based Assay Kit BioVision Cat# 600450
Alpha Ketoglutarate Dehydrogenase
Activity Colorimetric Assay Kit
BioVision Cat# K678-100
PDH enzyme activity dipstick assay kit Abcam Cat# ab109882
Alpha Ketoglutarate Assay Kit Abcam Cat# ab83431
QIAquick PCR Purification Kit QIAGEN Cat# 28106
RNeasy Mini Kit QIAGEN Cat# 74106
ReverTra Ace TOYOBO Cat# TRT-101
Thunderbird SYBR qPCR Mix TOYOBO Cat# QPS-201
KOD Fx Neo DNA polymerase TOYOBO Cat# KFX-201
BCA Protein Assay Kit TAKARA Cat# T9300A
Deposited Data
H3K4me3, H3K4me1 ChIP-seq dataset (Braz~ao et al., 2016) GEO: GSE72017
H3K27me3 ChIP-seq dataset (Vian et al., 2018) GEO: GSE82144
H3K27me3 ChIP-seq dataset (Caganova et al., 2013) GEO: GSE50912
H3K27Ac ChIP-seq dataset (Meng et al., 2014) GEO: GSE62296
STAT6 ChIP-seq dataset (Czimmerer et al., 2018) GEO: GSE106701
Experimental Models: Cell Lines
40LB feeder cell (Nojima et al., 2011) N/A
PLAT-E retroviral packaging cell line Dr. Toshio Kitamura (Tokyo University) RRID: CVCL_B488
Experimental Models: Organisms/Strains
Mouse: C57BL/6NCrSlc Japan SLC Inc. N/A
Mouse: B1-8hi (Shih et al., 2002) N/A
Mouse: C57BL/6-CD45.1 RIKEN BRC Cat# RBRC00144,
RRID:IMSR_RBRC00144
Oligonucleotides
For details of qPCR/ChIP primers and
shRNA used in this study, see Table S2
This paper N/A
Recombinant DNA
pMXs-IRES-GFP Dr. Toshio Kitamura (Tokyo University) N/A
pMXs-DLST-V5-IRES-GFP This paper N/A
pMXs-FLAG-SIAH2-IRES-Puro This paper N/A
pVSV-G Clontech Cat# 631530
pSIREN-GFP shLuciferase (shControl) (Koike et al., 2019) N/A
pSIREN-GFP shUTX This paper N/A
pSIREN-GFP shSTAT3 This paper N/A
pSIREN-GFP shSTAT5 This paper N/A
pSIREN-GFP shSTAT6 This paper N/A
pSIREN-GFP shIDH2 This paper N/A
pSIREN-GFP shSIAH2 This paper N/A
Software and Algorithms
FlowJo https://www.flowjo.com/solutions/flowjo RRID: SCR_008520
MetaboAnalyst 4.0 https://www.metaboanalyst.ca RRID:SCR_015539
Morpheus https://software.broadinstitute.org/
morpheus/
RRID:SCR_014975
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REAGENT or RESOURCE SOURCE IDENTIFIER
Galaxy https://main.g2.bx.psu.edu/ RRID:SCR_006281
ImageJ https://imagej.nih.gov/ij/ RRID:SCR_003070
Bowtie2 http://bowtie-bio.sourceforge.net/bowtie2/
index.shtml
RRID:SCR_005476
UCSC Genome Browser https://genome.ucsc.edu RRID:SCR_005780
GraphPad Prism 8 GraphPad Software RRID:SCR_002798
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OPEN ACCESS
RESOURCE AVAILABILITY
Lead ContactFurther information and requests for resources and reagents should be directed to and will be fulfilled by the Lead Contact, Daisuke
Kitamura ([email protected])
Materials AvailabilityThe reagents generated in this study may be made available on request upon completing a Materials Transfer Agreement.
Data and Code AvailabilityThe data that support the findings of this study are available from the corresponding author on request.
EXPERIMENTAL MODEL AND SUBJECT DETAILS
MiceC57BL/6NCrSlc (B6) mice were purchased from Japan SLC Inc. B1-8hi mice (Shih et al., 2002) were backcrossed to congenic B6-
CD45.1 strain. All animals were maintained in a mouse facility in Research Institute for Biomedical Sciences, Tokyo University of
Science (TUS) under specific pathogen-free conditions and were treated under protocols approved by the Animal Care and Use
Committee of the TUS. Experiments were done using sex- and age-matched mice between 6-12 weeks of age.
iGB cell cultureNaive B (NB) cells were purified from spleens by magnetic negative sorting using a cocktail of biotinylated Abs for CD4, CD8, CD43,
CD49b, Ter119, and Streptavidin Particles Plus DM and IMag system (BD Biosciences), and MACS system (Miltenyi Biotec) as
described previously (Nojima et al., 2011). Typically, 1x106 purified B cells were plated on 3x106 80-Gy-irradiated 40LB cells in a
10-cm dish and cultured for 3 days at 37�C with 5% CO2, 1 ng/mL IL-4 in 30 mL B cell medium (BCM): RPMI-1640 medium
(Wako) supplemented with 10% heat-inactivated fetal bovine serum (FBS), 50 mM 2-mercaptoethanol (2-ME), 10 mM HEPES pH
7.5 (HEPES), 100 U/ml penicillin and 100 mg/ml streptomycin (Pen-Strep) (GIBCO). To isolate iGB cells from the culture, 40LB cells
were removed using biotinylated anti-H-2Kd Ab (Biolegend), Streptavidin Particle Plus DM and the IMag system (BD Biosciences). In
some experiments, biotinylated anti-IgM and anti-IgE Abs (Biolegend) were further added to purify IgG1+ cells as shown in Fig-
ure S1C. To induce Bcl6+ cells, iGB cells cultured for 3 days were isolated and further cultured for 1 day in the BCM without feeder
cells (plain culture). As indicated, reagents were added to the plain culture at the concentration shown in Table S1. In some exper-
iments, 1 mM oligomycin, 10 mM GSK-J4, 10 mM MG-132, or 0.1 mM bafilomycin A1 were added to the plain culture as indicated. In
some cases, the plane culture was performed in glucose-free RPMI-1640 (Wako) supplemented with dialyzed 10% FBS, 2-ME,
HEPES, Pen-Strep and glucose at low (0.1 mM) or normal (10 mM) concentration with or without 5 mM DMaKG (Sigma) or 5 mM
DE-Suc (Wako). For iGB cell transfer experiment, 5 3 106 live iGB cells derived from CD45.1-B1-8hi mice were isolated and trans-
ferred into B6 mice on day 4 after immunization.
METHOD DETAILS
Immunization and in vivo treatmentsMice were immunized i.p. with 100 mg of NP34-CGG in alum unless otherwise noted. For isolation of GC B cells and PCs, mice were
administered i.v. with 5x108 of sheep red blood cells (SRBC) (Nippon Bio-Supp. Center). The following reagents or vehicle alone were
injected i.p. into immunizedmice: oligomycin (0.5mg/kg, Sigma) or GSK-J4 (10mg/kg, Sigma), each dissolved in PBS containing 5%
Tween 80 and 5% PEG 400; IL-4 complex (IL-4c), recombinant mouse IL-4 (2 mg, PeproTech) and anti-mouse IL-4 (10 mg, BioXCell,
clone: 11B11), mixed and diluted in 200 ml of PBS.
Cell Reports 33, 108333, November 3, 2020 e5
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OPEN ACCESS
Ex vivo cell purificationGCB cells and PCs weremagnetically enriched from pooled spleens of SRBC-immunizedmice using FITC-conjugated anti-GL7 and
PE-conjugated anti-CD138 Abs (Biolegend), anti-FITC and anti-PE MicroBeads (Miltenyi Biotec), with the MACS system (Miltenyi
Biotec). After enrichment, cells were further stainedwith respective Abs and sorted using FACSAria II or III (BDBiosciences) as shown
in Figure S2B. NB cells were sorted from unimmunized B6mice using FACSAria II or III as shown in Figure S2B. For in vivo analysis of
antigen-specific B cells, NB cells were purified from B1-8hi mice as described above, and the frequency of NP+ cells was determined
by flow cytometry, and then NB cells containing 104 NP+ B cells were transferred into B6 mice, which were then immunized i.p. with
NP-CGG in alum on the next day. For the lactate production assay, CD45.1+ donor B cells were magnetically enriched from pooled
spleens on day 3.5 or day 7 after immunization using FITC-conjugated anti-CD45.1 Ab (Biolegend), anti-FITC MicroBeads and the
MACS system. Then, enriched cells were further stained with respective Abs and sorted using FACSAria II or III with the gating strat-
egy as shown in Figure S2A.
Flow cytometrySingle-cell suspensions from spleens were prepared at the indicated days after immunization, red blood cells were lysed with ammo-
nium chloride buffer, and then cells were incubated with anti-CD16/32 Ab (2.4G2) to block FcgRs. iGB cells were collected with
MACS buffer (PBS supplemented with 0.5% BSA, 2 mM EDTA) at the indicated days of culture. Cells were stained with Abs and re-
agents on ice (for splenocytes) or at room temperature (for iGB cells). For staining total (surface and intracellular) IgG1 and IgE, iGB
cells were treated with a Fixation/Permeabilization solution and Perm/Wash buffer (BD Biosciences) or Foxp3/Transcription Factor
Staining Buffer Set (Thermo Fisher Scientific) according to the manufacturer’s protocol as described (Haniuda et al., 2016). Intracel-
lular Bcl6 was stained in cells treated with the Foxp3/Transcription Factor Staining Buffer Set. To monitor the mitochondrial or glyco-
lytic activity, cells were loaded with 100 nM MitoTracker, 500 nM TMRM, 5 mM MitoSOX Red or 10 mg/mL 2-NBDG (Thermo Fisher
Scientific) at 37�C with 5% CO2 for 30 min (or 10 min for MitoSOX) in glucose-free RPMI-1640 medium (Wako). After washing, cells
were stained for surface markers as described above and subjected to flow cytometric analysis. All samples were analyzed using
FACSCanto II, FACSAria II or III (BD Biosciences) with FlowJo software (Tree Star, Inc.). The gating strategies for iGB cells or B cells
ex vivo are shown in Figures S1B or S2B, respectively.
BrdU incorporation assayImmunized mice were given i.v. injection of 3 mg of BrdU (5-bromodeoxyuridine) (Sigma) dissolved in PBS, 1 h prior to euthanasia for
sampling. Splenocytes from these mice were washed with cold PBS, resuspended in 0.5 mL cold 0.15 M NaCl, to which 1.2 mL cold
95% ethanol was added dropwise while the tube was gently vortexed, and then left on ice for 30 min. These cells were then washed
and fixed with 1 mL of PBS containing 1% paraformaldehyde and 0.05% Tween 20 overnight at 4 C. Fixed cells were resuspended in
1 mL of DNase I buffer (0.15 M NaCl, 4.2 mM MgCl2, 10 mM HCl and 30 U/ml DNase I (Sigma)) and incubated for 30 min at room
temperature. The cells were washed and stained with Alexa 647-conjugated anti-BrdU Ab (Thermo Fisher Scientific) overnight at
4 C.
Immunoblotting and immunoprecipitationiGB cells were lysed with RIPA buffer (40 mM Tris-HCl pH 7.5, 150 mM NaCl, 1% NP-40, 1% sodium deoxycholate, 0.1% SDS and
1mMEDTA) supplemented with protease and phosphatase inhibitors for 25min on ice. Lysates were sonicated and then weremixed
with sample buffer and dithiothreitol (DTT) and boiled. NB cells and GC B cells were directly lysed with sample buffer with DTT, son-
icated and boiled. Boiled lysates were resolved on SDS-PAGE or Tricine-SDS-PAGE and transferred to PVDF membrane (Millipore),
followed by immunoblotting as previously described (Haniuda et al., 2016). For immunoprecipitation (IP) of STAT6, cells were lysed
with lysis buffer (40 mM Tris-HCl pH 7.5, 400 mM NaCl, 1 mMMgCl2, 0.1% NP-40, 1 mM EDTA, 0.5 mMDTT and 20% glycerol) with
protease and phosphatase inhibitors for 20 min on ice. Lysates were diluted with equal volume of dilution buffer (40 mM Tris-HCl pH
7.5, 5 mMMgCl2, 1.3 mg/ml bovine serum albumin (BSA), 0.5 mMDTT and 20% glycerol), precleared and then incubated with rabbit
anti-STAT6 Ab (Santa Cruz Biotechnology) or control IgG, followed by precipitation with Protein G Sepharose 4 Fast Flow (GEHealth-
care). For IP of FLAG- or V5-tagged protein, cells were lysed with 1% NP-40 lysis buffer (40 mM Tris-HCl pH 7.5, 150 mM NaCl, 1%
NP-40, and 1mMEDTA) with protease and phosphatase inhibitors for 25min on ice. The lysates were precleared and then incubated
with anti-FLAG (M2) Ab- or anti-V5 Ab-conjugated beads or control mouse IgG-conjugated beads (Sigma). After extensive washing
with IP-Wash buffer (40 mM Tris-HCl pH 7.5, 150 mMNaCl, 0.5% NP-40, 1 mM EDTA and 5% glycerol), the precipitates were boiled
in sample buffer with DTT and subjected to SDS-PAGE, followed by immunoblotting.
RT-PCR, qPCRTRI Reagent (Sigma) or RNeasyMini (QIAGEN) was used to isolate total RNA from B cells. cDNAwas generated from total RNA using
ReverTra Ace (TOYOBO) with oligo(dT)20 primer (Thermo Fisher Scientific) according to the manufacturer’s protocols. Quantitative
real-time PCR (qPCR) was performed using Thunderbird SYBR qPCRMix (TOYOBO) with 7500 fast Real-time PCR system or Quant-
Studio 3 (Applied Biosystems). For quantification of gene expression level, each samplewas normalized to the expression of a control
housekeeping gene,Gapdh,Hprt or Actb. The fold change in expression of each gene compared to a control sample, set as 1.0, was
calculated with the 2-ddCT method. Primers used in this study are listed in Table S2.
e6 Cell Reports 33, 108333, November 3, 2020
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OPEN ACCESS
Dehydrogenase activity assayPDH activity in cell lysates wasmeasured using the Enzyme Activity Dipstick Assay Kit (Abcam): Cells were lysed in the sample buffer
provided by the manufacturer, and protein concentration in the lysates were measured with BCA Protein Assay (Takara). Equal
amounts of lysates were used formeasuring PDH activity according to themanufacturer’s protocol. Band density was analyzed using
the ImageJ software. Mitochondria were isolated and mitochondrial IDH activity was assessed using a colorimetric assay as
described previously (Sun and Denko, 2014) with some modifications detailed in the following: To isolate mitochondria, 5-10 3
106 cells (iGB cell) or 2-6 3 107 cells (NB and GC B) were resuspended in 750 ml of hypotonic buffer (10 mM Tris-HCl pH 7.5,
10 mM NaCl and 1.5 mM MgCl2), incubated for 5 min on ice and homogenized by 20 stroke in 1 mL syringe with 26G needle. After
adding 500 mL of 2.5 3MS buffer (12.5 mM Tris-HCl pH 7.5, 2.5 mM EDTA, 175 mM sucrose and 525 mMmannitol), nuclei and un-
broken cells were removed by centrifugation at 8003 g for 5 min at 4�C, twice. Mitochondria were collected from the supernatant by
centrifuging at 10,0003 g for 10 min at 4�C and washed with 13MS buffer (diluted with water). The protein amount was determined
by BCA Protein Assay (Takara) and equal amounts of isolated mitochondria were lysed with IDH reaction buffer (50 mM Tris-HCl pH
7.5, 8mMMgCl2, 1mMMnCl2, 0.05mMEDTA, 0.2%Triton X-100, 10 mM rotenone, 10mM sodium citrate, 1.5mMsodium isocitrate,
2 mM ADP, 0.75 mM Nitro Blue Tetrazolium Chloride and 0.05mM Phenazine methosulfate) supplemented with either 2 mM NAD or
1 mM NADP, and incubated in 96 well plate at 37�C with 5% CO2 for 30 min. The reaction was stopped, and resultant blue formazan
was solubilized by adding an equal volume of 20%SDS in 0.02MHCl and incubating at 37�Covernight. OD at 590 nmwasmeasured.
For aKGDH activity, mitochondria were isolated as described above and the same amounts of mitochondria were loaded and
measured using the a-Ketoglutarate Dehydrogenase Activity Colorimetric Assay Kit (BioVision) according to the manufacturer’s
protocol.
Lactate production assayIsolated B cells were cultured in phenol red-free RPMI-1640 medium (Wako) supplemented with HEPES and incubated at 37�C with
5% CO2 for 4 hr. Lactate concentrations in the supernatant were measured with Glycolysis Cell-Based Assay Kit (BioVision) accord-
ing to the manufacturer’s protocol.
Plasmid constructionscDNAs forDLST and SIAH2were cloned by PCR fromRNA of day 3 B6-iGB cells using KOD FxNeo DNA polymerase (TOYOBO). V5-
tag (GKPIPNPLLGLDST) or FLAG-tag (DYKDDDDK) was fused to the C-terminal of DLST or N-terminal of SIAH, respectively, by
ligating the corresponding sequences with these cDNA using PCR-generated de novo restriction enzyme sites. The resultant
DNA was cloned into pMXs-IRES-GFP or pMXs IRES-Puro vector (kindly provided by T. Kitamura, University of Tokyo). For RNAi,
the target sequences of shRNAs, as listed in Table S2, were inserted into a pSIREN-GFP vector (Koike et al., 2019).
Retroviral TransductionTo produce retrovirus, pSIREN- or pMXs-based plasmids were co-transfected together with pVSV-G into Plat-E cells (kindly pro-
vided by T. Kitamura, University of Tokyo) by PEI Max (Mw 40,000; Polysciences). The virus-containing supernatant was harvested
2 days after transfection. For retroviral transduction of iGB cells, day 2 iGB cells weremixedwith the virus-containing supernatant and
were spin-infected at 2,000 rpm, 37�C for 90 min with 10 mg/ml DOTAP Liposomal Transfection Reagent (Sigma) and IL-4 (Pepro-
tech). One day later, cells were harvested, re-plated on new 40LB feeder layers with IL-4, and harvested on day 4 as shown in Fig-
ure S5A. Retroviral transduction of in-vivo-activated primary B cells and their transfer into mice were performed as previously
described (Koike et al., 2019). In brief, B1-8hi mice were injected i.p. with 50 mg of NP53-Ficoll, and then B cells were purified from
the spleens of these mice 6 hr later and stimulated in vitro with 2 mg/ml anti-CD40 Ab (BioXCell, clone: FGK4.5) for 18 hr. Cultured
B cells were mixed with the virus-containing supernatant and were spin-infected as above without IL-4. The resultant viable 106 B
cells were transferred into B6 mice, which were then immunized i.p. with NP-CGG in alum on the next day.
MetabolomicsFor metabolome analysis using capillary electrophoresis coupled with mass spectrometry (CE-MS), iGB cells (3-6 3 106 cells/sam-
ple) were washed twice by 5% mannitol solution and were lysed with 800 ml of methanol. The cell extract was mixed with 550 ml of
MilliQ water containing internal standards (H3304-1002, Human Metabolome Technologies, Inc., Tsuruoka, Japan) to standardize
the metabolite intensity and to adjust the migration time, and centrifuged at 2,3003 g for 5 min at 4�C. Eight hundred ml of the upper
aqueous layer was centrifugally filtered through a Millipore 5-kDa cutoff filter (Millipore) at 9,100 3 g for 120 min at 4�C to remove
proteins. The filtrate was centrifugally concentrated and resuspended in 50 ml of Milli-Q water and analyzed by Human Metabolome
Technologies Inc. (Yamagata, Japan) using CE-MS. Cationic compounds were measured in the positive mode of CE-TOFMS and
anionic compounds were measured in the positive and negative modes of CE-MS/MS as described previously (Soga and Heiger,
2000; Soga et al., 2002, 2003). Metabolite set enrichment analysis was performed using the MetaboAnalyst 4.0 web-based pipeline
(https://www.metaboanalyst.ca) to visualize metabolic pathway enrichment. Hierarchical clustering and the heatmap were gener-
ated using the Morpheus web interface (https://software.broadinstitute.org/morpheus/).
Cell Reports 33, 108333, November 3, 2020 e7
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OPEN ACCESS
aKG measurementB cells (1-83 107) were lysed with 400 ml of methanol containing 25 mM 2-isopropylmalic acid (Sigma) and centrifuged at 16,0003 g
for 5 min at 4�C. The supernatant was mixed with 320 ml of a mixture of water and chloroform (1:1), incubated for 5 min with agitation,
and was further mixed with 400 ml of water. After incubation for 5 min, the mixture was centrifuged as above, and the upper layer was
mixed with 320 ml of water and incubated for 5 min with agitation. The mixture was centrifuged as above, and the supernatant was
dried and re-dissolved in 60 ml of 20 mg/ml 2-methoxyamine hydrochloride (MP Biomedicals) in pyridine at 37�C for 1.5 hr. This so-
lution was mixed with 30 ml of N-methyl-N-trimethylsilyl-trifluoroacetamide (MSTFA) (GL Science), incubated at 37�C for 0.5 hr and
centrifuged at 16,0003 g for 5 min at 20�C. The resultant supernatant was subjected to gas chromatography coupled with MS (GC/
MS) measurement using GCMS-TQ8030 (Shimadzu) by Chemicals Evaluation and Research Institute (Saitama, Japan). Alternatively,
the amount of aKG was determined using alpha Ketoglutarate Assay Kit (Abcam) according to the manufacturer’s protocol.
Chromatin immunoprecipitation (ChIP) analysisOne times 107 cells were fixedwith 1% formaldehyde for 10minutes at room temperature and then lysedwith NB1 (50mMHEPESpH
7.9, 140 mM NaCl, 1 mM EDTA, 10% glycerol, 0.5% NP-40 and 0.25% Triton X-100). Nuclei were collected by centrifugation at
1,200 3 g for 5 min at 4�C and washed with NB2 (40 mM Tris-HCl pH 8.0, 200 mM NaCl, 1 mM EDTA and 0.5 mM EGTA) and lysed
with NB3 (40 mM Tris-HCl pH 8.0, 300 mM NaCl, 1 mM EDTA, 0.5 mM EGTA, 1% Triton X-100, 0.5% SDS and 0.1% sodium deox-
ycholate) and sheared by sonication for 10 min using Bioruptor (Sonic Bio) in TPX microtubes. The soluble chromatin supernatant
(‘input’) was incubated with the indicated Abs and precipitated with Dynabeads Protein G (Thermo Fisher Scientific). After de-cross-
linking for 4 hr at 65�C, samples were treated with RNase A (Sigma) for 30 min at 37�C, followed by treatment with Proteinase K
(Merck) for 1 hr at 55�C. Eluted DNA from ‘input’ and the immunoprecipitate were purified using QIAquick PCR Purification Kit (QIA-
GEN) according to the manufacturer’s protocol and analyzed by qPCR. Amounts of the products from the precipitated DNA were
presented as percentages of those from ‘input’ DNA. The primers were used for ChIP-qPCR are listed in Table S2. To analyze pub-
lished ChIP-sequencing data, available ChIP-seq Fastq files were obtained from GEO (https://www.ncbi.nlm.nih.gov/geo/) with
accession number GSE72017 (H3K4me3, H3K4me1) (Braz~ao et al., 2016), GSE82144 (H3K27me3, NB) (Vian et al., 2018),
GSE50912 (H3K27me3, GC B) (Caganova et al., 2013), GSE62296 (H3K27Ac) (Meng et al., 2014), and GSE106701 (STAT6) (Czim-
merer et al., 2018). Data were analyzed using the Galaxy platform (https://main.g2.bx.psu.edu/) and mapped onto the mm10 murine
genome using Bowtie2 aligner software (Version 2.3.4) as described previously (Yakushiji-Kaminatsui et al., 2018). Aligned read files
were visualized by obtaining snapshot tracks using the University of California Santa Cruz (UCSC) genome browser.
QUANTIFICATION AND STATISTICAL ANALYSIS
All statistical analyses were performed using GraphPad Prism 8 software. Comparisons between two groups were performed by a
two-tailed unpaired Student t test, except for the quantification of western blot analysis (Figure S7D), in which a two-tailed paired
Student t test was used. Comparisons between multiple groups were performed by one-way ANOVA with Tukey’s multiple compar-
ison or two-way ANOVA with Sidak’s test. P values less than or equal to 0.05 were considered statistically significant. Details
regarding statistical analyses of experiments can be found in the respective figure legends.
e8 Cell Reports 33, 108333, November 3, 2020
Cell Reports, Volume 33
Supplemental Information
Metabolic Reprogramming Induces
Germinal Center B Cell Differentiation
through Bcl6 Locus Remodeling
Kei Haniuda, Saori Fukao, and Daisuke Kitamura
Figure S1. IL-4 accelerates Bcl6 expression and GC B cell development, Related to Figure 1
(A) Quantification of changes in the number of IgG1+ cells (top) or the frequency of Fixable viability dye (FVD) positive
dead cells among total cells (bottom) after stimulation with the indicated cytokines or Abs during the plain culture of iGB
cells for 1 d as in Figure 1B. Results are presented as relative to the cells cultured with medium alone. (B) Gating strategy for
flow cytometric analysis of fixed iGB cells after the plain culture for 1 d with medium alone. FVD–, singlet cells in a
lymphocyte gate, as defined by forward and side scatters (FSC, SSC), were gated for IgG1+ or IgE+. (C) Enrichment of IgG1+
iGB cells by removing 40LB cells and IgM+ and IgE+ cells from the iGB cultures on day 3 using anti-H2Kd, anti-IgM, and
anti-IgE Abs (left), verified by flow cytometry (right). (D) Flow cytometric analysis of spleen cells from C57BL/6 (B6) mice
that had been immunized with 50 µg of NP-CGG in alum 7 days previously and administrated with PBS alone (–) or IL-4
complex (IL-4c) daily during day 4 to 6. Experimental procedure (left), the frequency of GC B cells (GL7+CD38lo) among
NP-specific B cells (NP+B220+CD138–) (middle) and the number of the NP-specific GC B cells per spleen (right). (E) Schema
of glycolysis and mitochondrial oxidative metabolism. PDH, pyruvate dehydrogenase; ETC, electron transport chain; I-V,
complex I-V. Data are mean±s.d. of two to four biological replicates (A). Each symbol represents an individual mouse and
horizontal lines indicate mean ±s.d. of six biological replicates (D). Data are pooled from two to four independent
experiments (A), or representative of at least three (B and C) or two (D) independent experiments. P values were calculated
by two-tailed unpaired Student’s t-test (D).
A B
C
Glucose
Pyruvate Lactate
PDH
Acetyl-CoA
TCA cycleNADHFADH2
ATP
ETCOligomycinV
IVIIIIII
Glycolysis
E
0 103 104 105
0
103
104
105
87
IgG1
IgE
40LB + IL-4, 3 d – 40LB– IgM+
– IgE+
IgG1+ cellenrichment
DC
ells
per
spl
een
(x 1
05 )
–IL-
4c
0 103 104 105
0
103
104
105
GL7
CD
38
– IL-4c
24 55
P = 0.0004
B6
NP-CGGalum
0day: 4 5 6 7
–IL-4c
0
2
4
6
8
10
Rel
ativ
e to
med
ium
alo
ne
anti-I
gG
anti-C
D40SCFGMCSF
TGFβIFNγ
IFNα
IL-33
IL-28
A
IL-23
IL-27
IL-21
IL-17
F
IL-17
A
IL-15
IL-13
IL-12
IL-10IL-9
IL-7
IL-6
IL-5
IL-4
IL-3
IL-2
IL-1β
IL-1α
Number of IgG1+
0
1
2
3
0
1
2
3FVD+ dead cell
0 100K 200K
0
103
104
105
FSC-A
FVD
74 99
0 100K 200KFSC-A
SSC
-A
0
100K
200K
SSC
-W
990 100K 200K
FSC-H
0
100K
200K
0 103 104 105
0
103
104
105
IgG1
IgE
50
16
990 100K 200K
SSC-H
SSC
-W
0
100K
200K
Figure S2. Gating strategies for flow cytometry, analyses of PDH in sorted B cell subsets, and effect of oligomycin on
Tfh cell development, Related to Figure 2
(A) Gating strategy for flow cytometric analysis of spleen cells from B6 mice (CD45.2+) that had been transferred with B
cells of CD45.1+ B1-8hi mice and immunized with NP-CGG in alum on the following day. Within FVD- and TER-119-negative
singlet cells in a lymphocyte gate, defined are pre-GC B cells (CD45.1+B220+CD138–NP+GL7+CD38hi, on day 3.5 after
immunization), GC B cells (CD45.1+B220+CD138–NP+GL7+CD38lo, on day 7), and plasma cells (PC: CD45.1+B220loCD138+,
on day 7) in the immunized mice, and naive B cells (NB: B220+IgD+) in unimmunized B6 mice. (B) Sorting strategy for GC
0 103 104 105
CD138
0
103
104
105
B220
12
86
48
50
A
0 100K 200KFSC-A
SSC
-A
0
100K
200K
0 100K 200KFSC-H
FSC
-W0
100K
200K
88
0 100K 200KSSC-H
SSC
-W
0
100K
200K
97
83
0 103 104 105
B220
0
103
104
105
IgD
47
920 100K 200K
FSC-A
0
103
104
105
FVD
TER
-119
0.13
2.6
0 103 104 105
CD45.1
0
103
104
105
CD
138
51
830 103 104 105
GL7
0
103
104
105
CD
38
82
90
0 103 104 105
0
103
104
105
NP-
bind
ing
B220
NB
pre-GC BDay 3.5
Day 7
Unimmunized
GC B
PC
CNB GC B PC
PDH activity
D
-37
PDH-E1α
p-PDH-E1α
NB GC B
-37
B
9850
0 103 104 105
CD38
0
103
104
105
B220
NB
Post-flow cytometry sorting
B6
SRBC i.v.
0 8 Spleenday:GL7+ cellsCD138+ cellsmagnetic sorting
Flow cytometrysorting
0 103 104 105
CD138
0
103
104
105
B220
50
20
100
100
0 103 104 105
CD138
0
103
104
105
B220
570 103 104 105
GL7
0
103
104
105
CD
38
GC B
0 103 104 105
GL7
0
103
104
105
CD
38
PC
Post-magnetic sorting
Post-flow cytometry sorting
Post-flow cytometry sorting
B6Unimmunized
–
Oligomyci
n0
50
100
150 P = 0.20
Bcl6
+ (%)
0 103 104 105
Bcl6
0Even
ts(%
of m
ax)
100
80
60
40
20
PCGC BGC B
–Oligomycin
E
F
0 103 104 105
0
103
104
105
CXCR5
PD-1 4.6 4.3
Oligomycin–
Non-TfhTfhTfh
–Oligomycin
0 103 104 105
Bcl6
0Even
ts(%
of m
ax)
100
80
60
40
20
GBc
l6 M
FI in
Tfh
(x 1
03 )
–
Oligomyci
n0.0
0.5
1.0
1.5 P = 0.32
0
5
10
15
20
Cel
ls p
er s
plee
n (x
105 )
P = 0.77
–
Oligomyci
n
Unimmun
ized
B, PC and NB cells. From spleen cells of B6 mice immunized with SRBC 8 d previously, both GL7+ cells and CD138+ cells
were enriched by magnetic sorting, and then GC B cells (B220+GL7+CD38lo) and PC (B220+GL7+CD38lo) were further sorted
by flow cytometry (left). NB cells (B220+CD38+) were sorted from unimmunized B6 mice (right). (C) Representative images
of a dipstick assay measuring enzymatic activity of PDH in mitochondrial fractions of indicated B cells sorted as in (B).
Quantified data are shown in Figure 2D. (D) Immunoblot analysis with the antibodies specific for phosphorylated (p-) or total
PDH-E1a subunit of the sorted NB and GC B cells as in (B). (E) Gating for Bcl6+ cells on GC B cells defined as in (A) for
Figure 2H (left), and the frequency of Bcl6+ cells among GC B cells (right). (F and G) Flow cytometric analysis of Tfh cells
in the spleen from B6 mice immunized with NP-CGG in alum 8 d previously and administered 0.5 mg/kg oligomycin or
vehicle alone (–) i.p. 1 d prior to analysis. The frequency of Tfh cells (CXCR5hiPD-1hi) among CD4+ cells (F, left), the number
of Tfh cells per spleen (F, right), Bcl6-staining in Tfh and Non-Tfh cells (CD4+CXCR5–PD-1–) (G, left), and MFI of Bcl6-
staining (G, right) are shown. Data are mean±s.d. of seven (E) or six (F and G) biological replicates and each symbol
represents an individual mouse (E-G). Data are representative of at least three (A-C) or two (D and E) independent experiments
or from an experiment (F and G). P values were calculated by two-tailed unpaired Student’s t-test (E and G) or one-way
ANOVA with Tukey’s test (F).
Figure S3. IL-4 induces metabolic reprograming in iGB cells, Related to Figure 3
(A) Quantification of Blimp1 and Bcl6 mRNAs by qRT-PCR in purified IgG1+ iGB cells stimulated with either IL-4 or anti-
IgG for 6 hr, or left untreated (–) for 1 hr, as in Figure 3A. (B) Heatmap representing metabolite content profiling for IgG1+
iGB cells prepared as in Figure 3A. Metabolite profile of each sample of the cells is depicted as a row (n = 3 biologically
independent samples per group). Columns show normalized levels of each metabolite concentration (z-score). Clustering of
the treatments is described by the dendrogram on the right. Clustering of metabolites is described by the dendrogram on the
top. (C) Amount of aKG in purified IgG1+ iGB cells treated with IL-4 for 3, 6, 24 hr or left unstimulated (–) for 1 hr. Data
are mean ±s.d. of three technical replicates (A) or three biological replicates (C). Each symbol represents a biologically
independent sample (C). Data are representative of two independent experiments (A) or from an experiment (B and C).
A Column z-score
-2 0 2
–
Ile
Sper
min
eH
omoc
yste
ine
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IL-4
anti-IgGmR
NA
expr
essi
on(re
lativ
e)
–
6 hr IL
-4
6 hr a
nti-Ig
G
Blimp1Bcl6
0
1
2
B
0
1
2
3
4
5αKG
Rel
ativ
e am
ount
1 3 6 24 hr
–IL-4
C
Figure S4. Histone modification and STAT6 binding at the Bcl6 and Irf4 locus, Related to Figure 4
(A) Genome browser tracks of ChIP-seq analysis showing histone modifications and STAT6-binding over the Bcl6 gene locus.
Data were obtained from GEO public database with accession number GSE72017 (H3K4me3, H3K4me1), GSE82144
(H3K27me3, NB), GSE50912 (H3K27me3, GC B), GSE62296 (H3K27Ac), GSE106701 (STAT6). The positions of primers
for ChIP-qPCR analysis used in this study are shown as red lines, and the numbers in red indicate distance (kb) from
the transcription start site (+0). Act.B, activated B cells by stimulation with anti-CD40 and IL-4 for 2.5 d; Mf, bone marrow
derived macrophage stimulated with IL-4 for 1 hr. (B) ChIP-qPCR analysis with control rabbit IgG at the Bcl6 locus of purified
IgG1+ iGB cells after the plain culture with IL-4 or anti-IgG for 6 hr. Data were normalized to the input DNA. Numbers on
the x-axis indicate the distance (kb) from the transcription start site (+0). (C) Genome browser tracks of ChIP-seq analysis of
the Irf4 locus presented as in (A). Data were obtained as in (A). (D) ChIP-qPCR analysis at the Irf4 locus performed as in (B).
(E) ChIP-qPCR analysis for H3K27me3 at the Bcl6 locus of purified IgG1+ iGB cells treated for 6 hr with IL-4 in the absence
(–) or presence of oligomycin (1 µM). (F) qRT-PCR analysis for Bcl6 mRNA in purified iGB cells treated with IL-4 for 1 d
in the absence (–) or presence of oligomycin (1 µM) or DMaKG (5 mM). Data are mean ±s.d. of three technical replicates
(B, D-F) and representative of at least three (B and D) or two (E and F) independent experiments.
Figure S5. Retroviral transduction of iGB cells and knockdown of UTX, Related to Figure 5
(A) Strategy for retrovirus (Rv) transduction of iGB cells. Day 2 iGB cells were infected with Rv, further cultured for 2 d,
then isolated, and cultured in medium alone for 1 d. A representative flow cytometry data of the cells transduced with pMXs-
IRES-GFP empty vector (Ev) is shown on the right, with numbers indicating the frequency of GFP+ cells among live singlet
iGB cells on day 5. (B) Analysis for Kdm6a knockdown efficiency. iGB cells were transduced as in (A) with Rv (pSIREN-
GFP) containing an shRNA for either luciferase (shControl) or Kdm6a (shUTX). At day 4 of culture, GFP+ iGB cells were
sorted by flow cytometry for the RT-qPCR analysis. (C and D) iGB cells derived from CD45.1 B1-8hi were transduced with
Rv expressing GFP and shControl or shUTX as in (A), purified at day 4 and treated with IL-4 for 1 d under low glucose (Lo,
0.1 mM) conditions with or without 5 mM DMaKG, and then transferred into recipient mice that had been immunized i.p.
with NP-CGG in alum 4 d previously. Spleen cells from the mice were analyzed by flow cytometry on day 8 after
immunization. Experimental protocol (C). Shown are representative plots with numbers indicating the frequency of
CD45.1+GFP+ cells among live lymphocytes (D, left), and the number of the donor GFP+ GC B cells
(CD45.1+GFP+CD19+CD138–NP+GL7+CD38lo) per spleen (D, right). Data are mean ±s.d. of three technical replicates (B)
or five biological replicates (D). Each symbol represents an individual mouse (D). Data are representative of at least four (A)
or two (B and D) independent experiments. P values were calculated by two-way ANOVA with Sidak’s test (D).
A B
0.0
0.4
0.8
1.2
mR
NA
expr
essi
on(re
lativ
e)
shCon
trol
shUTX
Kdm6a
B6
40LB + IL-4
– 40LBRv
2 40day: 5Medium
0 103 104 105
GFP
FSC
-A
0
100K
200K
pMXs-IG (Ev)
78
C
B6
NP-CGG in alum
4 80day:
Low Glc± DMαKG
CD45.1 B1-8hi
IL-440LB + IL-4
– 40LBRv
2 40day: 5
i.v.
D
0 103 104 105
0
103
104
105
GFP
CD
45.1 0.21 1.5 0.16 0.30
Glc:DMαKG:
Lo–
Lo+
shControl shUTXLo–
Lo+
0
1
2
Lo+
Lo–
Glc:DMαKG:
shControl shUTX
Lo+
Lo–
P = 0.20P < 0.0001P < 0.0001
Cel
ls p
er s
plee
n (x
106 )
Figure S6. Knockdown of STAT and retroviral transduction of in vivo-activated primary B cells, Related to Figure 6
(A) Flow cytometric analysis of iGB cells after the plain culture in medium in the absence (–) or presence of 5 mM DMaKG
for 1 d. Numbers indicate frequencies of Bcl6+ cells and CD138+ PCs among IgG1+ gated cells. (B) Analysis for Stat
knockdown efficiency. B6 iGB cells were transduced as in Figure S5A with Rv (pSIREN-GFP) containing an shControl or an
shRNA for each Stat. At day 4 of the culture, GFP+ iGB cells were sorted by flow cytometry, and then analyzed by RT-qPCR
for expression of each indicated Stat mRNA. (C) Experimental procedure of Rv transduction for in vivo analysis. CD45.1 B1-
8hi B cells primed by NP-Ficoll in vivo were cultured with anti-CD40 Ab, transduced with Rv, and then transferred into B6
mice, which were then immunized with NP-CGG in alum. At day 7 after immunization, splenocytes from these mice were
analyzed by flow cytometry. To estimate transduction efficiency, the Rv-infected B cells were further cultured for 1 d in
medium alone and analyzed by flow cytometry for the frequency of GFP+ cells among NP-binding B cells (a representative
data is shown). Data are mean ±s.d. of three technical replicates (B) and representative of at least three (A), two (B) or four
(C) independent experiments.
A
C
Stat3 Stat5a Stat6Stat5b
mR
NA
expr
essi
on(re
lativ
e)
shCon
trol
shSTAT3
0.0
0.4
0.8
1.2
0.0
0.4
0.8
1.2
0.0
0.4
0.8
1.2
0.0
0.4
0.8
1.2
shCon
trol
shSTAT5
shCon
trol
shSTAT5
shCon
trol
shSTAT6
anti-CD40
Rv infection18 hr
6 hr
NP-Ficoll 3 hr
B6
NP-CGGalum
0 7-1day:
CD45.1 B1-8hi
48
0 100K 200KFSC-A
0
103
104
105
NP-
bind
ing
0 103 104 105
GFP
49
0
103
104
105
NP-
bind
ing
pMXs-IG (mock)1 d
Medium
i.v.
B
0 103 104 105
0
103
104
105
CD138Bc
l6
– DMαKG33
3.1
29
4.0
Figure S7. Analyses of expression and function of DLST, Related to Figure 7
(A) Analysis of Idh2 knockdown efficiency. B6 iGB cells were transduced as in Figure S5A with Rv (pSIREN-GFP)
containing an shControl or an shIDH2. At day 4 of the culture, GFP+ iGB cells were sorted by flow cytometry, and then
analyzed by RT-qPCR. (B and C) qRT-PCR analysis for the expression of aKGDH subunits, in NB or GC B cells sorted as in
Figure S2B (B), or in purified IgG1+ iGB cells after the plain culture with either IL-4 or anti-IgG for 6 hr (C). (D)
Quantification of the relative expression of DLST protein in NB and GC B cells analyzed by immunoblotting as in Figure 7G.
Densitometric data were normalized to those of tubulin served as loading controls. (E) Siah2 knockdown efficiency analyzed
by RT-qPCR as in (A). (F) Flow cytometric analysis of spleen cells from mice day 3.5 post-immunization that had received
B cells transduced with Rv expressing GFP and shControl or shSIAH2. Shown are representative plots with numbers
indicating the frequency of GFP+ cells among donor pre-GC B cells (CD45.1+B220+CD138–NP+GL7+CD38hi) (left), and the
number of the donor GFP+ pre-GC B cells per spleen (right). (G) Flow cytometric analysis of iGB cells transduced as in
Figure S5A with empty Rv (pMXs-IRES-GFP; Ev) or Rv expressing DLST, and cultured with IL-4 for the last 1 d. Shown is
a representative flow cytometry plots with numbers indicating frequencies of Bcl6+ cells or CD138+ PCs among GFP+IgG1+
cells. (H) Flow cytometric analysis on day 7 after immunization with NP-CGG in alum of mice that had been transferred with
B1-8hi B cells of post-transduction (as in Figure S6C) with Ev or Rv expressing DLST. Frequency of gene-transduced (GFP+)
cells among the donor GC B cells (CD45.1+B220+CD138–NP+GL7+CD38lo) (left) and the number of the GFP+ donor GC B
cells per spleen (right). Data are mean ±s.d. of three (A, D and E) six (F) or five (H) biological replicates or three technical
replicates (B and C). Each symbol represents a biological sample of triplicate transductions (A and E), a biological sample
from n = 1 mice (NB in D) or pooled from 10 mice (GC B in D), or an individual mouse (F and H). Data are representative
of two (A-C, E and G) independent experiments, or are pooled from three independent experiments (D), or from an experiment
(F and H). P values were calculated by two-tailed unpaired (A, E, F and H) or paired (D) Student’s t-test.
A EBm
RN
A ex
pres
sion
(rela
tive)
shCon
trol
shIDH2
0.0
0.4
0.8
1.2Idh2
shCon
trol
shSIAH2
0.0
0.4
0.8
1.2
mR
NA
expr
essi
on(re
lativ
e)
Siah2
mR
NA
expr
essi
on(re
lativ
e)
Ogdh Dlst Dld0.0
0.5
1.0
1.5
2.0 NBGC B
IL-4anti-IgG
Ogdh Dlst Dld0.0
0.5
1.0
1.5
mR
NA
expr
essi
on(re
lativ
e)
C D
NBGC B
0.0
0.4
0.8
1.2
Prot
ein
expr
essi
on(re
lativ
e)
DLST
H
Cel
ls p
er s
plee
n (x
105 )
G
0 103 104 105
0
103
104
105
CD138
Bcl6
Ev DLST
32
115.5
66
0 103 104 105
0
103
104
105
GFP
CD
45.1
Ev DLST
29
EvDLS
T
P = 0.0061
P = 0.0030 P < 0.0001P = 0.0002
0
2
4
6
8F
0
1
2
3
Cel
ls p
er s
plee
n (x
105 )
shCon
trol
shSIAH2
P = 0.078
45
0 103 104 105
0
103
104
105
GFP
CD
45.1
shControl shSIAH2
39 35
Donor pre-GC B cells
Table S1. List of cytokines used in this study, Related to STAR Methods
Cytokine or Ab Manufacture
IL-1a 10 ng/mL PeproTechIL-1b 10 ng/mL PeproTechIL-2 10 ng/mL PeproTechIL-3 10 ng/mL PeproTechIL-4 1 ng/mL PeproTechIL-5 10 ng/mL PeproTechIL-6 10 ng/mL PeproTechIL-7 10 ng/mL PeproTechIL-9 10 ng/mL PeproTechIL-10 10 ng/mL PeproTechIL-12 10 ng/mL BiolegendIL-13 10 ng/mL PeproTechIL-15 40 ng/mL PeproTechIL-17A 10 ng/mL PeproTechIL-17F 10 ng/mL PeproTechIL-21 10 ng/mL PeproTechIL-23 1 ng/mL BiolegendIL-27 100 ng/mL BiolegendIL-28A 10 ng/mL PeproTechIL-33 10 ng/mL PeproTechIFNa 200 ng/mL BiolegendIFNg 20 ng/mL PeproTechTGFb 2 ng/mL PeproTechGMCSF 10 ng/mL PeproTechSCF 10 ng/mL PeproTechanti-CD40 5 µg/mL BioXCellF(ab')2 anti-mouse IgG 5 µg/mL Jackson ImmunoResearch
Conc.
Table S2. List of primers used in this study, Related to STAR Methods
For RT-qPCR For ChIP-qPCR Bcl6 locus For ChIP-qPCR Irf4 locusPrimer name Sequence 5' to 3' Primer name Sequence 5' to 3' Primer name Sequence 5' to 3'Actb Fw CTAAGGCCAACCGTGAAAAG –359 Fw ACCCCGGGGCTTACTGTTAT –60 Fw ACCTGGTACGGTGGCTATCT
Actb Rv ACCAGAGGCATACAGGGACA –359 Rv CAGGCGGGTCAGAGACAATA –60 Rv TGCTACGAAGGCTGGTCTTG
Bcl6 Fw CCGGCACGCTAGTGATGTT –352 Fw CTCGCCCTCGTGTATCCTCT –35 Fw TGGGGCGTCTATGAGTCCAT
Bcl6 Rv TGTCTTATGGGCTCTAAACTGCT –352 Rv TGGTGGACCTAGGCCATTCT –35 Rv ATGGCAAGGGTGTGACTCTC
Dld Fw GGGAGCACATATTCTAGGACCA –225 Fw TTTAAATGCTGCCCACGGTC –12 Fw GGATGAGGCCCCTGGAATTT
Dld Rv TCACAGGAAGCACCATATTCC –225 Rv ACTTGGGCCCCATTGTTTCA –12 Rv TCCAAAGCACGCTGTCAGAT
Dlst Fw AGCCTCCTTCTAGCAAACCA –217 Fw CTCATTTGGCACGCTCCCTA –1.4 Fw GCAGCAAGGCTGTGCTATCT
Dlst Rv ACGCAGACCTTTAGCAGCTC –217 Rv CCTACCATGCCATCAGCACT –1.4 Rv AACACCTTCTGTCTGTCGGG
Gapdh Fw TGAAGCAGGCATCTGAGGG –213 Fw CAGCAGTGATCCGTGAAGGT –0.5 Fw TCGTCGGTTTCATTCACCCA
Gapdh Rv CGAAGGTGGAAGAGTGGGAG –213 Rv TCCCAGGTCCCCATAATGCT –0.5 Rv GGCAAAGCGGAGTCTTGTCT
Hprt Fw TCCTCCTCAGACCGCTTTT –176 Fw TGGGCTGATCACAGACAACC 0 Fw CTAGGACCTGTGCACTTCGG
Hprt Rv CCTGGTTCATCATCGCTAATC –176 Rv ACCACTGTTCCAAGGTCGTG 0 Rv CAGTCCCATTAGCTCGTCCC
Idh2 Fw GGATGTACAACACCGACGAGT –163 Fw GCTCGGTGAGAGTGACTGAC +1.1 Fw GACTTCGGAGACTCTGGCAC
Idh2 Rv CGGCCATTTCTTCTGGATAG –163 Rv ATGAATCTGTCCGCAGCGTT +1.1 Rv CCCTGCAACTACCTTCGCAT
Irf4 Fw CTACCCCATGACAGCACCTT –146 Fw CCTTCGCCCCACCGTATAAA
Irf4 Rv CCAAACGTCACAGGACATTG –146 Rv GGGCTGTGAATGCCTGCTAT
Kdm6a Fw CGGGTTCGTGAGGTTTCAT –10 Fw CAGTCTAGGTCATTGGCGCT
Kdm6a Rv GAGATTCGTAGCAGCGAACA –10 Rv GCGGCATGACCTCTGTCTTTA
Ogdh Fw TCTCATCCACAGACAAACTTGG –5 Fw ACTTTTCCATTCACATCTCCACAG
Ogdh Rv AGGAAGTGCTGGCTCCTGT –5 Rv TGAAAAAGTTTCTGCGGGCG
Prdm1 Fw GAACCTGCTTTTCAAGTATGCTG –1.8 Fw AAGTCCTTCAAGTGGCTCGT
Prdm1 Rv AGTGTAGACTTCACCGATGAGG –1.8 Rv AAGCCCACGTTTAGGGTTGT
Siah2 Fw ATGCCGCCAGAAGTTAAGC 0 Fw CTGGTGTCCGGCCTTTCCTA
Siah2 Rv CAGCCCGTGGTAGCATACTTA 0 Rv CCGCAGCTCAAATTCCGAGA
Stat3 Fw GTTCCTGGCACCTTGGATT +0.9 Fw ACTGCCTCGACTCCAACCAA
Stat3 Rv CAACGTGGCATGTGACTCTT +0.9 Rv GTTTTGGGAAGGCTTCGCTT
Stat5a Fw GAGCTGGTGTTCCAGGTGA +1.2 Fw AAACACAGCTTGCACCAAGG
Stat5a Rv GGTGGCAGTAGCATTGTGG +1.2 Rv GGCCGCGGTGTTTGTATTTT
Stat5b Fw GAAACGAGCTGGTCTTTCAAGT +4 Fw GGTGCTACTGGTCCGTATCG
Stat5b Rv CTGGCTGCCGTGAACAAT +4 Rv TCCTACACTGCGCAACAAGT
Stat6 Fw GTCCATGAGTGTACTGCCATCT +7 Fw GGAGATTTCCGCCCAACCTT
Stat6 Rv GGCATGGTTATCTGGCTCAT +7 Rv CCCAGTCTCCACGGTTTCAG
+10 Fw ATCCTGGCACTGTAGGCAAC
shRNA +10 Rv CCCTCTGGCCCTTCACTAAC
sh Name Target Sequence 5' to 3' +17 Fw TCTGCTGGAGCGTGGTTATC
shSTAT3 GGAGCAGCATCTTCAGGATGT +17 Rv CTGGCACTTACCGTCTCCAG
shSTAT5 GCAACCACCTCGAGGACTACA +24 Fw AAATAGCGACCTGACGCACA
shSTAT6 GGAAGGGAAACAGCATCTTGC +24 Rv GGGTGACCGACAGACATTCA
shUTX GCAGAATACTTCTGATAATTG +35 Fw TGCCACCTTGTGGCCATTCT
shIDH2 GCACGTTCAAGTTGGTCTTCA +35 Rv TTTTAGCAACTCTTGGCTTCCCA
shSIAH2 GGAAGCTGTGATGTCCCATCT