Research Techniques Made Simple: Induced Pluripotent Stem Cells in Dermatological Research

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Research Techniques Made SimpleInduced
Pluripotent Stem Cells in Dermatological Research

• Jason Dinella1-3, Maranke I. Koster1-3, and Peter
  J. Koch1-4
• 1. Department of Dermatology,
• 2. Charles C. Gates Center for Regenerative
  Medicine and Stem Cell Biology,
• 3. Graduate Program in Cell Biology, Stem Cells
  and Development,
• 4. Department of Cell and Developmental Biology,
• University of Colorado School of Medicine,
  Aurora, Colorado, USA

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Induced Pluripotent Stem Cells (iPSCs)

• iPSCs are pluripotent cells generated from
  somatic cells through the forced expression of
  reprogramming factors controlling self-renewal
  and pluripotency.
• iPSCs can be generated from patient biopsies.
• iPSCs can be differentiated into any cell type of
  the body.

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iPSC Technology

• Can be used to study basic cell biology and
  mechanisms driving cellular differentiation.
• Presents the ideal alternative approach to using
  embryonic stem cells (ESCs) in disease modeling
  and therapeutic applications.
• Allows researchers to sidestep ethical and
  immunological limitations associated with the
  generation and use of ESCs.

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Human iPSC Generation
Cellular Reprogramming
Clonal Expansion/ Characterization
2-3 weeks
3-4 weeks
Somatic cells
Putative iPSCs (arrow)
iPSCs
Characterization
a
c
d
b
SSEA-3
NANOG
TRA 1-60
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Keratinocyte Differentiation
TP63 KRT14
LOR KRT14
DSC3 KRT14
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Methods of Inducing Pluripotency
Reprogramming Method Integrative? Efficiency References
Retrovirus Yes Moderate Takahashi et al., 2006
Adenovirus No Low Stadtfeld et al., 2008
Lentivirus Yes Moderate-High Sommer et al., 2009
Transposible element Yes Low Woltjen et al., 2009
Episomal vectors No Low Yu et al., 2009
Protein No Low Zhou et al., 2009
Sendai virus No High Fusaki et al., 2009
mRNA/miRNA No Moderate-High Warren et al., 2010
Small molecules No Moderate Hou et al., 2013
Stimulus-triggered No High Obokata et al., 2014
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Summary and Future Directions
Please insert Figure 4 (being redrawn) of Dinella
et al., 2014 here
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Advantages and Limitations of iPSCs

• iPSCs can be generated from skin biopsies.
• iPSCs can be cultured indefinitely in vitro,
  providing a renewable source of cells.
• iPSCs can be differentiated into any cell type of
  the body.
• Cells differentiated from iPSCs can be used for
  disease modeling and drug screening.
• Disease-causing mutations can be corrected in
  iPSCs
• iPSC-derived cells, such as keratinocytes, can be
  used in cell therapy.
• Generation of iPSCs involves the use of adult
  cells, bypassing ethical concerns associated with
  using ESCs.

• iPSCs can acquire genetic mutations during
  reprogramming or during in vitro culture.
• Undifferentiated iPSCs, if transferred to a
  patient, could form tumors (teratomas).
• More stringent protocols must be developed and
  standardized for the generation, maintenance,
  characterization, and differentiation of iPSCs
  before they can be considered a viable option for
  clinical use.