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THE STEM CELL BIOLOGY KNOWLEDGE THE STEM CELL BIOLOGY KNOWLEDGE
APPLIED TO REGENERATIVE MEDICINEAPPLIED TO REGENERATIVE MEDICINE
AND TO THE AND TO THE IN VITROIN VITRO MODELS OF MODELS OF
HUMAN DISEASESHUMAN DISEASES
STEM CELL: A FUNCTIONAL DEFINITIONSTEM CELL: A FUNCTIONAL DEFINITION
Stem cells are defined functionally as cells that have the capacity to self-renew as
well as the ability to generate differentiated cells (Weissman et al. 2001; Smith,
2001).
Main properties of Stem Cells:
1)1) SelfSelf--renewalrenewal;
2)2) ClonalityClonality;
3)3) PotencyPotency.
STEM CELL: A WORKING DEFINITIONSTEM CELL: A WORKING DEFINITIONA clonal, self-renewing entity that is multipotent and thus can generate several
differentiated cell types.
WHAT ARE STEM CELLS?WHAT ARE STEM CELLS?
• Cells which can generate other cells/cell types.
• They can divide infinitely. This is the so called self-renewalproperty.
• On the basis of their origin they can be embryonic, fetal (cord blood) or adult stem cells.
• Adult stem cells are tissue specific (eg, hematopoietic, neural, muscle stem cells).
• Terminally differentiated cells cannot divide, however tissuespecific stem cells or their derivatives the progenitor/precursorcells can replace them.
• So tissue specific stem cells are the sources of tissue replacement/regeneration.
• There are tumor stem cells as well.
WHERE DO STEM CELLS COME FROM?WHERE DO STEM CELLS COME FROM?
At the egg cylinder stage of embryonic development (embryonic day (E) 6.5 in mice), a
population of cells near the epiblast can be identified as primordial germ cells (PGCs),
which are subsequently excluded from somatic specification or restriction (Saitou et al.)
2002).
«PG», «EG» AND «ES» CELLS«PG», «EG» AND «ES» CELLS
Cell lines that can be maintained for variable
periods in vitro in a morphologically
undifferentiated state have been obtained
from from morulaemorulae or blastocysts of a variety of or blastocysts of a variety of
species of mammals in addition to species of mammals in addition to
the mousethe mouse. What such ES-like (ESL) cells lines
have in common with murine ES cells, in
addition to a morphologically undifferentiated morphologically undifferentiated
appearance and expression of various genes expression of various genes
associated with associated with pluripotencypluripotency, is a high high
nuclear/cytoplasmic rationuclear/cytoplasmic ratio.
«ES» CELLS AND «ESL» CELLS«ES» CELLS AND «ESL» CELLS
ADULT STEM CELLSADULT STEM CELLS
AN EXAMPLE OF ADULT STEM CELL: HSCAN EXAMPLE OF ADULT STEM CELL: HSC
HOW TO IDENTIFY, ISOLATE AND CHARACTERIZE STEM CELLS HOW TO IDENTIFY, ISOLATE AND CHARACTERIZE STEM CELLS –– ES CELLSES CELLS
In animal species, in vivo differentiation can be assessed rigorously by the
ability of ES cells to contribute to all somatic lineages of ES cells to contribute to all somatic lineages and produce germ line produce germ line
chimerismchimerism. These criteria are not appropriate for human ES cells; consequently,
these cells must generate embryoid bodies and teratomas containing
differentiated cells of all three germ layers. Moreover human ES cells must
be shown to be positive for well-known molecular markers
of pluripotent cells.
HOW TO IDENTIFY, ISOLATE AND CHARACTERIZE STEM CELLS HOW TO IDENTIFY, ISOLATE AND CHARACTERIZE STEM CELLS ––ADULT STEM CELLSADULT STEM CELLS
The basic characteristics of an adult stem cell are a single cell (clonal) that self-renews
and generates differentiated cells. The most rigorous assessment of these characteristics
is to prospectively purify a population of cells (usually by cell surface markers), transplant
a single cell into an acceptable host without any intervening in vitro culture, and observe
selfrenewalselfrenewal and tissue, organ, or lineage reconstitutionand tissue, organ, or lineage reconstitution.
THE FOREFRONT OF ADULT STEM CELLS RESEARCHTHE FOREFRONT OF ADULT STEM CELLS RESEARCH
Two concepts about the fate or potential of stem cells have moved to
the forefront of adult stem cell research.
(i)(i) PlasticityPlasticity
(ii)(ii) TransdifferentiationTransdifferentiation
«STEMNESS»: TOWARD A MOLECULAR DEFINITION OF STEM CELLS«STEMNESS»: TOWARD A MOLECULAR DEFINITION OF STEM CELLS
Although stems cells in different cellular microenvironments or niches will by
necessity have different physiological demands and therefore distinct molecular
programs, there are likely certain genetic characteristics specific to and shared by genetic characteristics specific to and shared by
all stem cellsall stem cells.
A molecular fingerprint for stem cellsmolecular fingerprint for stem cells. This fingerprint could be used as the basis for a
molecular definition of stem cells that, when combined with their functional
definition, would provide a more comprehensive set of criteria for understanding their
unique biology.
(i) Activated signal transduction pathways: TGF(i) Activated signal transduction pathways: TGF--bb, Notch, , Notch, WntWnt, and , and JakJak/Stat family /Stat family
members;members;
(ii) Rapid cycling; (ii) Rapid cycling;
(iii) Telomere maintenance; (iii) Telomere maintenance;
(iv) Significantly remodeled chromatin; (iv) Significantly remodeled chromatin;
(v) Posttranscriptional regulatory machinery regulated by RNA helicases of the Vasa type; (v) Posttranscriptional regulatory machinery regulated by RNA helicases of the Vasa type;
(vi) Resistance to stress, mediated by multidrug resistance transporters, protein(vi) Resistance to stress, mediated by multidrug resistance transporters, protein--folding folding
machinery, machinery, ubquitinubquitin, and detoxifier systems., and detoxifier systems.
COMMON MOLECULAR FINGERPRINTING OF STEM CELLSCOMMON MOLECULAR FINGERPRINTING OF STEM CELLS
Somatic cell reprogramming Somatic cell reprogramming is the process of converting the epigenetic state of a
differentiated somatic cell into a pluripotent state capable of giving rise to any cell type.
Due to this ability to differentiate into all somatic cell types, pluripotent stem cells bear
promise to advance biomedical research and regenerative medicineadvance biomedical research and regenerative medicine. [SCNT= Somatic [SCNT= Somatic
Cell Nuclear Transfer]Cell Nuclear Transfer]
DIRECT REPROGRAMMING OF SOMATIC CELLS TO A DIRECT REPROGRAMMING OF SOMATIC CELLS TO A PLURIPOTENT STATEPLURIPOTENT STATE
Gurdon J.B., Sci.Amer. 1968
LIMITS AND CHALLENGES OF LIMITS AND CHALLENGES OF SCNTSCNT
Several problems have impeded the use of SCNT as a general tool to derive
human ES cells for stem cell therapy:
1) the current inability to perform SCNT with human cellsinability to perform SCNT with human cells;
2)2) lack of knowledge of the underlying principles of this procedurelack of knowledge of the underlying principles of this procedure;
3)3) important ethical concerns (Cloning)important ethical concerns (Cloning).
iPSCsiPSCs: HOPES AND CHALLENGES: HOPES AND CHALLENGES
hOct4; hSox2; hOct4; hSox2; hKlf4; h chKlf4; h c--MycMyc
YamanakaYamanaka Cocktail:Cocktail:OSKMOSKM
HUMAN HUMAN iPSiPS CELLS EXPRESS CELLS EXPRESS hEShES MARKERSMARKERS
Human iPS cells expressedmany undifferentiated ES
cell-marker genes (Adewumiet al.,2007), such as OCT3/4OCT3/4, SOX2SOX2, NANOGNANOG, growth and
differentiation factor 3 (GDF3GDF3), reduced expression 1
(REX1REX1), fibroblast growthfactor 4 (FGF4FGF4), embryoniccell-specific gene 1 (ESG1ESG1),
developmental pluripotency-associated 2 (DPPA2DPPA2), DPPA4DPPA4,
and telomerase reverse transcriptase (hTERThTERT) at
levels equivalent to or higherthan those in the hES cell line
H9 and the human embryonic carcinoma cell
line, NTERA-2
The global gene-expression patterns were compared between human compared between human iPSiPS cells (clone cells (clone
201B7) and HDF, and between human 201B7) and HDF, and between human iPSiPS cells and cells and hEShES cells (H9) with oligonucleotide cells (H9) with oligonucleotide
DNA microarraysDNA microarrays. Arrows indicate the expression levels of Nanog, endogenous Oct3/4
(the probe derived from the 30 untranslated region, which does not detect the retroviral
transcripts), and endogenous Sox2. The red lines indicate the diagonal and 5-fold changes
between the two samples.
GLOBAL GENEGLOBAL GENE--EXPRESSION PATTERNS ARE EXPRESSION PATTERNS ARE SIMILAR, BUT NOT SIMILAR, BUT NOT IDENTICALIDENTICAL, BETWEEN HUMAN , BETWEEN HUMAN iPSiPS CELLS AND CELLS AND hEShES CELLSCELLS
HUMAN HUMAN iPSiPS CAN DIFFERENTIATE IN A LOT OF DIFFERENT CAN DIFFERENTIATE IN A LOT OF DIFFERENT CELL TYPES CELL TYPES
From From iPSCsiPSCs to to NeuronsNeurons
From From iPSCsiPSCs to to CardiacCardiac CellsCells
Both ES and ES and iPSiPS cell lines cell lines are powerful powerful
research tools and could provide research tools and could provide
substantial quantities of diseasesubstantial quantities of disease--relevant relevant
cells for biomedical researchcells for biomedical research
1)1) study of complex diseases study of complex diseases that emerge from a
mixture of genetic and environmental effects;
2)2) cellcell--based drug screening based drug screening in disease-
relevant cell types;
3) The use of pluripotent cells as a renewablerenewable
source for transplantation medicinesource for transplantation medicine
INSULININSULIN--PRODUCING CELLS DERIVED FROM STEM CELLS: A PRODUCING CELLS DERIVED FROM STEM CELLS: A
POTENTIAL TREATMENT FOR POTENTIAL TREATMENT FOR DIABETESDIABETES
ALTHOUGH INSULIN WAS DISCOVERED OVER 75 INSULIN WAS DISCOVERED OVER 75
YEARS AGOYEARS AGO, THE COMPLICATIONS OF DIABETES
STILL PRODUCE DEVASTATING CONSEQUENCES.
THE LINK BETWEEN HIGH BLOOD GLUCOSE LEVELS
AND THE COMPLICATIONS OF RETINOPATHY,
NEPHROPATHY, AND NEUROPATHY IS NOW
ESTABLISHED BEYOND DOUBT.
EDMONTON PROTOCOL (EDMONTON PROTOCOL (2000): 2000): PROOFPROOF--OFOF--PRINCIPLE FOR PRINCIPLE FOR THE CONCEPT OF THE CONCEPT OF CELLULAR TRANSPLANTS AS A TREATMENT CELLULAR TRANSPLANTS AS A TREATMENT
FOR DIABETESFOR DIABETES. .
Nonetheless, the expectations from the Nonetheless, the expectations from the Edmonton results have not met expectations.Edmonton results have not met expectations.
THE SUPPLY OF INSULIN PRODUCING PANCREATIC b CELLS,
WHICH IS CURRENTLY ONLY FROM CADAVER DONORS, IS
INSUFFICIENT, AND LIMITS THE EXTENSION OF THIS
THERAPY. IN THE UNITED STATES, IT WOULD BE A MAJOR IN THE UNITED STATES, IT WOULD BE A MAJOR
CHALLENGE CHALLENGE
TO OBTAIN 3000 USABLE CADAVER PANCREASES PER YEARTO OBTAIN 3000 USABLE CADAVER PANCREASES PER YEAR.
R Lanza. In Essentials of Stem Cell Biology, Second Edition. 2009
Much attention is so focused on finding on finding
new sources of insulin producing cellsnew sources of insulin producing cells that
can be used for transplantation, or finding or finding
that islet regeneration can be inducedthat islet regeneration can be induced.
The quest includes exploring the potential of
1) embryonic and adult stem cells1) embryonic and adult stem cells,
2) 2) transdifferentiationtransdifferentiation such as directing directing acinaracinar cells or cells or
hepatocytes to make insulinhepatocytes to make insulin,
3)3) altering cells with altering cells with bioengineeringbioengineering,
4) 4) developingdeveloping human cell lineshuman cell lines,
5)5) use of use of bb cells from other species as cells from other species as xenograftsxenografts.
POTENTIAL SOURCES OF PANCREATIC POTENTIAL SOURCES OF PANCREATIC bb--CELLSCELLS
KNOWLEDGE OF PANCREATIC AND ISLET DIFFERENTIATION KNOWLEDGE OF PANCREATIC AND ISLET DIFFERENTIATION PROVIDES IMPORTANT HELP FOR WORK WITH ESCsPROVIDES IMPORTANT HELP FOR WORK WITH ESCs
A DETAILED UNDERSTANDING OF THE MOLECULAR EVENTS THAT GOVERN THE A DETAILED UNDERSTANDING OF THE MOLECULAR EVENTS THAT GOVERN THE
EMBRYONIC DEVELOPMENT OF THE PANCREAS WILL HAVE AN IMMEDIATE IMPACT EMBRYONIC DEVELOPMENT OF THE PANCREAS WILL HAVE AN IMMEDIATE IMPACT
ON CLINICAL RESEARCH RELATING TO THIS ISSUEON CLINICAL RESEARCH RELATING TO THIS ISSUE
ExocrineExocrine Pancreas Pancreas (98% of the total mass of the pancreas): acinar cells and ductular cells
Endocrine Pancreas Endocrine Pancreas (1-2% of the total mass ofthe pancreas): a-cells (Gcg); b-cells (Ins); PP-cells
(PP); d-cells (somatostatin); e-cells (proteohormoneghrelin regulates food uptake)
PdxPdx11: early role for this transcription factor, whichis different from its role at a later stage inmaintaining b cell differentiation;
NgnNgn33: is expressed in precursor cells committedto differentiating into islets;
PaxPax44: appears to play a key role in post Ngn3bcell differentiation;
Other transcription factors important for b celldevelopment are BETABETA22//NeuroDNeuroD, NkxNkx22..22, NkxNkx66..11,and MafAMafA, which seems to be especiallyimportant for the final stages of b celldifferentiation.
(i) PRODUCTION OF (i) PRODUCTION OF bb--CELLS FROM HUMAN EMBRYONIC CELLS FROM HUMAN EMBRYONIC STEM CELLSSTEM CELLS
FIVE STAGES EMPLOYED PARTICULAR CULTURE CONDITIONS AND ADDED
DIFFERENTIATION FACTORS:
1) DEFINITIVE ENDODERM (ACTIVIN AND WNT SIGNALINGACTIVIN AND WNT SIGNALING);
2) PRIMITIVE FOREGUT (EPIDERMAL GROWTH FACTOR AND FIBROBLAST EPIDERMAL GROWTH FACTOR AND FIBROBLAST
GROWTH FACTOR 10 (FGF 10GROWTH FACTOR 10 (FGF 10);
3) POSTERIOR FOREGUT (RETINOIC ACID, CYCLOPAMINERETINOIC ACID, CYCLOPAMINE);
4) PANCREATIC ENDODERM AND ENDOCRINE PRECURSORS (gg--SECRETASE SECRETASE
INHIBITOR, EXENDIN 4INHIBITOR, EXENDIN 4);
5) HORMONE EXPRESSING ENDOCRINE CELLS (EXENDIN4, IGF1, HEPATOCYTE EXENDIN4, IGF1, HEPATOCYTE
GROWTH FACTORGROWTH FACTOR).
(2009)(2009) ((--))--INDOLACTAM V INDOLACTAM V WORKS INDUCINGWORKS INDUCINGPANCREATIC PROGENITORS FROM PANCREATIC PROGENITORS FROM
DEFINITIVE ENDODERMDEFINITIVE ENDODERM
TITRATION OF TITRATION OF ILVILV FROM 20 FROM 20 nMnM TO 5 TO 5 uMuM
SHOWED THAT IT SHOWED THAT IT FUNCTIONS IN A DOSEFUNCTIONS IN A DOSE--
DEPENDENT MANNER WITH THE HIGHEST DEPENDENT MANNER WITH THE HIGHEST
EFfiCACYEFfiCACY AND NO DETECTABLE TOXICITY AT AND NO DETECTABLE TOXICITY AT
300 300 nMnM
THE EFFECT OF ILV WAS SUBSTANTIALLY IMPROVED IN THE PRESENCE OF FGF10, BUT NOT THE EFFECT OF ILV WAS SUBSTANTIALLY IMPROVED IN THE PRESENCE OF FGF10, BUT NOT
THE OTHER FACTORS. WHEN A POPULATION OF THE OTHER FACTORS. WHEN A POPULATION OF HUES 8HUES 8--E CELLS E CELLS WAS WAS TREATED WITH A TREATED WITH A
COMBINATION OF 300 COMBINATION OF 300 nMnM ILV AND 50 ILV AND 50 ngng/ml FGF10, AFTER 4 DAYS CULTURE, 45.8 /ml FGF10, AFTER 4 DAYS CULTURE, 45.8 ±± 5.6% OF 5.6% OF
THE CELLS WERE STAINED WITH PDX1 ANTIBODYTHE CELLS WERE STAINED WITH PDX1 ANTIBODY. IF THE HUES 8. IF THE HUES 8--E POPULATION IS TREATED E POPULATION IS TREATED
WITH FGF10 BUT NOT ILV, ONLY 5.8 WITH FGF10 BUT NOT ILV, ONLY 5.8 ±± 1.5% OF THE POPULATION EXPRESSES PDX1.1.5% OF THE POPULATION EXPRESSES PDX1.
(ii) THE POTENTIAL OF ADULT STEM/PROGENITOR CELLS AS (ii) THE POTENTIAL OF ADULT STEM/PROGENITOR CELLS AS A SOURCE OF INSULINA SOURCE OF INSULIN--PRODUCING CELLSPRODUCING CELLS
Replication of Replication of existingexisting bb--cellscells vsvs NeogenesisNeogenesis
Lifetime of a ratrat b-cell as approximately 58 days58 daysHumanHuman pancreatic b-cells can live for many yearsmany years
The frequent finding of insulin positive clusters The frequent finding of insulin positive clusters
of cells appearing to emerge from pancreatic of cells appearing to emerge from pancreatic
ducts in adult pancreases, and the very low rate ducts in adult pancreases, and the very low rate
of of bb cell, suggest that cell, suggest that neogenesisneogenesis is an is an
important contributor to the increase important contributor to the increase
in mass in adult humansin mass in adult humans. .
Hypothesis that islets are derived from islets are derived from
differentiated duct cells in the pancreas, differentiated duct cells in the pancreas,
which can serve as facultative which can serve as facultative
multipotentmultipotent progenitor cellsprogenitor cells. Particularly
suggestive has been finding that human
duct cells in tissue culture can form cysts
from which budding islet cells emerge;
these have been called cultivated human
islet buds (CHIBs). (Weir G, 2009)
ARGUMENTS FAVORING THE DUCTAL ORIGIN OF NEW ARGUMENTS FAVORING THE DUCTAL ORIGIN OF NEW ISLETSISLETS
PANCREATIC NONPANCREATIC NON--DUCT CELL CANDIDATE PRECURSOR CELLSDUCT CELL CANDIDATE PRECURSOR CELLS
Other candidate precursor cells have been found in the
pancreas. Two groups have found single cells from mouse single cells from mouse
pancreas that can form from clonal aggregates in culture,
which can be differentiated to express can be differentiated to express bb cell markers, and cell markers, and
even some insulineven some insulin.
A more provocative hypothesis is that A more provocative hypothesis is that b b cells have the cells have the
capacity to capacity to dedifferentiatededifferentiate to cells that can be markedly to cells that can be markedly
expanded through replication, and can then expanded through replication, and can then
differentiate back to a differentiate back to a bb cell phenotype cell phenotype..
PANCREATIC NONPANCREATIC NON--DUCT CELL CANDIDATE PRECURSOR CELLSDUCT CELL CANDIDATE PRECURSOR CELLS
STRICTLY SPEAKING, THE CONCEPT THAT DIFFERENTIATED DUCT STRICTLY SPEAKING, THE CONCEPT THAT DIFFERENTIATED DUCT
CELLS CAN FORM NEW ISLETS, AS WAS DISCUSSED ABOVE, COULD CELLS CAN FORM NEW ISLETS, AS WAS DISCUSSED ABOVE, COULD
BE CONSIDERED A FORM OF TRANSDIFFERENTIATION. CURRENT BE CONSIDERED A FORM OF TRANSDIFFERENTIATION. CURRENT
CLAIMS ABOUT CLAIMS ABOUT TRANSDIFFERENTIATIONTRANSDIFFERENTIATION NOW NOW
INCLUDE PANCREATIC ACINAR CELLS, HEPATOCYTES, AND BONE INCLUDE PANCREATIC ACINAR CELLS, HEPATOCYTES, AND BONE
MARROW. MARROW.
TRANSDIFFERENTIATIONTRANSDIFFERENTIATION
The The quest to find insulin producing cells that might quest to find insulin producing cells that might
be used for transplantation is intensebe used for transplantation is intense. Rapid . Rapid
improvements in our understanding of the improvements in our understanding of the
mechanisms of cellular development and a wide mechanisms of cellular development and a wide
array of potential stem or precursor cell candidates array of potential stem or precursor cell candidates
provide fuel for optimism that adult cells could solve.provide fuel for optimism that adult cells could solve.
iPSiPS CELLS IN CELLS IN TYPE 1 DIABETES TYPE 1 DIABETES RESEARCH AND TREATMENTRESEARCH AND TREATMENT
iPSiPS CELL LINES HAVE BEEN GENERATED CELL LINES HAVE BEEN GENERATED
FROM A FROM A PIMA INDIAN PIMA INDIAN WITH DIABETES AND WITH DIABETES AND
FROM TWO INDIVIDUALS WITH FROM TWO INDIVIDUALS WITH
AUTOIMMUNE DIABETESAUTOIMMUNE DIABETES
IN VITRO IN VITRO DIFFERENTIATION OF PLURIPOTENT STEM CELLS DIFFERENTIATION OF PLURIPOTENT STEM CELLS RECAPITULATES THE STEPWISE PROCESS OF EMBRYONIC RECAPITULATES THE STEPWISE PROCESS OF EMBRYONIC
DEVELOPMENTDEVELOPMENT
TO TRANSLATE THE GREAT PROMISE OF TO TRANSLATE THE GREAT PROMISE OF iPSiPS CELLS TO T1D TREATMENT, CELLS TO T1D TREATMENT, SEVERAL HURDLES HAVE TO BE OVERCOMESEVERAL HURDLES HAVE TO BE OVERCOME
1) The reprogramming process must be optimized and achieved 1) The reprogramming process must be optimized and achieved without without
the risk of introducing genetic changes that may have deleterious the risk of introducing genetic changes that may have deleterious
consequencesconsequences
2) A comparison of a panel of 2) A comparison of a panel of hEShES cell lines revealed variations among the lines in cell lines revealed variations among the lines in
their propensity to differentiate into the pancreatic lineage, and a similar trend their propensity to differentiate into the pancreatic lineage, and a similar trend
was suggested for human was suggested for human iPSiPS cells. The underlying basis for these variations is not cells. The underlying basis for these variations is not
clear, indicating clear, indicating a need for a better understanding of the differentiation process as a need for a better understanding of the differentiation process as
well as an epigenetic and functional analysis of the pluripotent starting population well as an epigenetic and functional analysis of the pluripotent starting population
and progenitors at each step of differentiationand progenitors at each step of differentiation..
3) The third obstacle is the need to 3) The third obstacle is the need to purify the βpurify the β--cells cells derived from derived from
pluripotent cells in order to avoid transplanting undifferentiated pluripotent cells in order to avoid transplanting undifferentiated
cells, which could form cells, which could form teratomasteratomas..
CONCLUSIONS (i)CONCLUSIONS (i)
hESCshESCs CAN BE UTILIZE TO DERIVE COMPLETELY CAN BE UTILIZE TO DERIVE COMPLETELY
DIFFERENTIATED CLINICALLY RELEVANT CELL DIFFERENTIATED CLINICALLY RELEVANT CELL
POPULATIONSPOPULATIONS
iPSiPS CELLS DERIVED FROM PATIENTS WITH GENETIC CELLS DERIVED FROM PATIENTS WITH GENETIC
DISEASES WILL PROVIDE A UNIQUE OPPORTUNITY TO DISEASES WILL PROVIDE A UNIQUE OPPORTUNITY TO
EXPLORE GENOTYPEEXPLORE GENOTYPE--PHENOTYPE CORRELATION AND PHENOTYPE CORRELATION AND
MAY ULTIMATELY BE USED TO VALIDATE GENOMEMAY ULTIMATELY BE USED TO VALIDATE GENOME--WIDE WIDE
ASSOCIATION STUDIES…BUT IT WILL TAKE A LONG TIME ASSOCIATION STUDIES…BUT IT WILL TAKE A LONG TIME
TO UNRAVEL THE FINAL GOAL OF THERAPY (ROUNTREE TO UNRAVEL THE FINAL GOAL OF THERAPY (ROUNTREE
CB: STEM CELLS IN DRUG DISCOVERY, REGENERATIVE CB: STEM CELLS IN DRUG DISCOVERY, REGENERATIVE
MEDICINE AND CANCER. GENOME MEDICINE 2011, MEDICINE AND CANCER. GENOME MEDICINE 2011,
3:15)3:15)
CONCLUSIONS (ii)CONCLUSIONS (ii)
BIBLIOGRAPHYBIBLIOGRAPHY
1) Disease-specific induced pluripotent stem (iPS) cells. In-Hyun Park et al. Cell. 2008
September 5; 134(5): 877–886;
2) iPS Cells in Type 1 Diabetes Research and Treatment. R Maehr. Clin Pharmacol Ther. 2011
May;89(5):750-3;
3) In vivo reprogramming of adult pancreatic exocrine cells to b-cells. Zhou Q et al. Nature.
2008 Oct 2;455(7213):627-32;
4) A functionally characterized test set of human induced pluripotent stem cells. Gabriella L
Boulting et al. Nat Biotechnol. 2011 Mar;29(3):279-86;
5) Conversion of Adult Pancreatic α-cells to β-cells After Extreme β-cell Loss. Thorel F et al.
Nature. 2010 Apr 22;464(7292):1149-54;
6) A small molecule that directs differentiation of human ESCs into the pancreatic lineage.
Chen S et al. Nat Chem Biol. 2009 Apr;5(4):258-65;
7) Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors.
Takahashi K et al. Cell. 2007 Nov 30;131(5):861-72.
