Current Understanding and Clinical Management of the

Current Understanding and Clinical Management of the Wiskott-Aldrich Syndrome

FabioCando*

DivisionofImmunologyandAllergyCentreHospitalierUniversitaireVaudois

Lausanne

Wiskott A. “Familiärer, angeborener Morbus Werlhofii?”

Monatsschr Kinderheilkd 1937;68:212-216

AlfredWisko-(1898–1978)

Fic. 1. Pedigree showing 6 generations of family in which some male infantssuffer from sex-linked recessive disease.

PEDIGREE OF SEX-LINKED RECESSIVE CONDITION 135

and a Y chromosome derived from the male

parent, and a male will result. The im-portant point is that a male receives hislone X chromosome from his mother. The

Y chromosome lacks a genetically activeregion which is present in the X. We assumethat a gene leading to the disease is locatedin the portion of the X which is not presentin the Y, and shall use the letters “de” tosymbolize the gene when it is in the con-dition leading to the disease and the letters“Dc” when the gene is in the condition lead-ing to normal , development. Females whoare genetically “Dc de” or “Dc Dc” areclinically normal with respect to this dis-ease. Males who are “Dc Y” are normal,while those who are “de Y” are diseased.Note that one gene in the condition Sym-

bolized by “de” is sufficient to lead to thedisease in the male, but not in the female.This is so because the second X in thefemale carries the gene “Dc” leading to

normal development, while the Y chromo-some carries no representative of the gene.

We can test this hypothesis as follows:Refer to figure 1. Starting with the indexpatient (VI-28), it follows that his mother(V-16), grandmother (IV-6), and great-grandmother (111-5) carried the gene, be-cause each of them must have transmittedthe gene for it to have ultimately reachedthe index patient. IV-7, who is an identicaltwin of IV-6, must also carry the gene “de,”because identical twins are geneticallyidentical. With this information, and on thebasis of the assumed theory, we can pre-dict how many affected and healthy maleswould be expected, exclusive of the indexpatient. The method of computation is asfollows: 111-5 is known to carry the gene inone of her X chromosomes. The probabilitythat she would pass it on to any particulardaughter (other than the grandmother ofthe index patient and the grandmother’s

by guest on February 24, 2016Downloaded from

Aldrich R.A. et al. “Pedigree demonstrating a sex-linked recessive condition characterized by

draining ears, eczematoid dermatitis and bloody diarrhea” Pediatrics 1954;13:133-139

RobertAldrich(1917-1999)

Wiskott-Aldrich Syndrome

Thrombocytopenia

Immunological SynapsePodosomes Microvilli CytokinesisActin polymerization

Infections: pneumoniaInfec2onsEczema Malignancies


Infections: pneumonia Autoimmunity

XLT / Mild WAS Severe / Classical WAS

WASPHOMOLOGYGTPaseBINDING

PROLINERICHREGION V C A

1 137 210 230 310 312 417 423 502

BR

Wiskott-Aldrich Syndrome

Thrombocytopenia


Infections: pneumoniaInfec2ons


Infections: pneumonia

PuckJM,Cando*F.NEnglJMed2006;355:1759

Ac2npolymeriza2on Microvilli

Immunologicalsynapse

CytokinesisPodosomes

Eczema Malignancies


Infections: pneumonia Autoimmunity

T lymphocytes! Reduced numbers (abnormal thymic output, increased apoptosis)! Disorganized immunological synapsis! Defect in activation and proliferation in response to anti-CD3! Defective migration to SDF-1a! Reduced IL-2, IFN-γ, TNF-α production

B lymphocytes!  Abnormal filopodia, motility, spreading, and aggregation !  Low IgM, high IgA serum levels!  Defective response to polysaccharide antigens

Wiskott-Aldrich syndrome: Immunodeficiency

NK cells!  Disorganized immunological synapsis!  Decreased migration!  Decreased cytotoxic activity

Dendritic cells! Abnormal ruffles, lamellopodia, and filopodia! Reduced motility and IFN-γ, production

Monocytes!  Abnormal filopodia, podosomes, and migration

Neutrophils!  Defective adhesion, integrin rearrangement and spreading!  Decreased migration, degranulation and respiratory burst


B lymphocytes

0100200300400500600700800

0 10 20 30 40 50

years

abs

cell

num

ber

CTRLWAS

T lymphocytes

050010001500

2000250030003500

0 10 20 30 40 50

years

abs

cell

num

ber

CTRLWAS

Immunodeficiency is progressive and associated to age-dependent lymphopenia

MALIGNANCIES (13-22%)LymphomaLeukemiaMyelodysplasia

INFECTIONS Bacterial:

Upper and lower respiratoryGastrointestinalMeningitisSepsis

Fungal: CandidaP. jirovecii

Viral:HSV, VZVMolluscum contagiosum


AUTOIMMUNITY (40-70%)

Autoimmune Manifestations in WAS

Skin vasculitis Inflammatory bowel disease

Renal disease

Wiskott-Aldrich syndrome: Autoimmunity

0 4000 8000 12000

CPM

T-eff

T-eff/T-reg(CTR)

T-eff/T-reg(WAS6)

0 20000 40000 60000

CPM

T-eff

T-eff/T-reg(CTR)

T-eff/T-reg(WAS12)

CD

4

CD25

WAS Autoimmunity: Regulatory T Cell Defects

T-eff Treg

Adrianietal.,ClinImmunol.2007;124:41-8

General problem of auto-antibody production?

Autoimmune hemolytic anemia

in WAS (~36%)

Wiskott-Aldrich syndrome: Autoimmunity

IgA nephropathy in WAS (~4%)

IgG

Autoantibody Arrays in WAS patients

Crestanietal.,JAllergyClinImmunol.2015;136:1401-4

B cell repertoire selection in WAS

MeffreandWardemann,CurrOpinImmunol2008

MaturenaïveB-cellBCRclones

Kolhatkaretal.,JExpMed.2015;212:1663-77

B cell repertoire selection in WAS

New Emigrant

Mature Naive

0

20

40

60

WAS1WAS2

WAS4WAS3

HD

0.1 1 100

1

2

3

4OD405

HD29

B

E

A

Non HEp-2 reactive (%) HEp-2 reactive (%)

PreGT-mature naÏve B cells

HD WAS0

20

40

60

% o

f pol

yrea

ctiv

e B

cel

l clo

nes

**

New Emigrant

Mature Naive

0

20

40

60

WAS1WAS2

WAS4WAS3

HD

HD WAS0

10

20

30

40

% o

f ant

i-nuc

lear

B c

ell c

lone

s

New Emigrant

Mature Naive

0

10

20

30

40

WAS patientsHD

0.1 1 100

1

2

3

4OD405

WAS1

0.1 1 100

1

2

3

4OD405

WAS2

0.1 1 100

1

2

3

4OD405

WAS3

0.1 1 100

1

2

3

4

µg/mL

OD405WAS4

1855.6

44.4

19 19 1557.9 52.6 53.3

42.1 43.4 46.7

2075.0

25.0HD WAS

0

20

40

60

% o

f HE

p-2-

reac

tive

B c

ell c

lone

s

**

C

HEp-

2

D

Figure 3

MaturenaïveB-cellBCRclones

Palaetal.,JClinInvest.2015;125:3941-51

! Prevention of complications from thrombocytopenia and immunodeficiency •  Chemoprophylaxis •  Immunoglobulin supplementation •  Splenectomy •  Eltrombopag, Romiplostim

! Gene therapy

! Hematopoietic stem cell transplantation •  <15% WAS patients have HLA-id. sib

Wiskott-Aldrich Syndrome: Treatment Options

! Autoimmunity •  Steroids, IVIg, Rituximab •  IL-2? •  Rapamycin?

Assessment of long-term efficacy of HCT in WAS Moratto et al. Blood 2011;118:1675-1684

Long-termcomplica2ons:28.9%

•  ChronicGVHD• Autoimmunity

• Neurologicsequelae

Overallsurvival(%

)

Timea]ertransplanta2on(months)

Upto1999(72)

Since2000(122)

Allpa2ents(194)

0 60 120 180 240 300 3600

10

20

30

40

50

60

70

80

90

100

MACROPHAGES

STEM CELLS

RED BLOOD CELLS

PLATELETS

T CELLS

B CELLS

BASOPHILS

EOSINOPHILS

NEUTROPHILS

COMMITTED PROGENITOR CELL

Gene Therapy for Primary Immunodeficiencies

Gene Therapy of Wiskott-Aldrich syndrome

Current Gene Therapy Trials for WAS

Gene Therapy For Primary Immunodeficiency: What is at the Horizon?

ZincFingerNucleasesMeganucleasesTALENsCRISPR/Cas-9Adeno-associatedVectors

Gene editing strategies for Wiskott-Aldrich Syndrome

RecombinedDonorFragment(1,599nt)

ZFN(mouseWasKOEScells)

12MW

mEx3-122A

GFPHomologyArmL

SA

HomologyArmRpA Pgk-PuroTKloxp loxp

mouseWasgene

1 2 3 4 5 6 7 8 9 10 11 12

neoR

ZFNCRISPR/Cas-9

ACKNOWLEDGEMENTS

MarsilioAdrianiRobertSokolicElizabethGarabedian

JayashreeJagadeesh

DougBurkeLisaPeterson

NaVonalInsVtutesofHealth

LuigiNotarangelo,CHB,Boston,MAEricMeffre,YaleU.,NewHaven,CTDavidRawlings,SCRI,Sea-le,WA

Collaborators

StefanoVolpiEle-raSantoriMarcDescatoire

IAL-CHUV

Documents

Current Understanding and Clinical Management of the