Turning Human Epidermis Into Pancreatic Endoderm

Article View

The Review of Diabetic Studies,2010,7,2,158-167.
Published:August 2010
Type:Original Article
Author(s) affiliations:

Pere Santamaria1,2,*, Ignacio Rodríguez-Pizá1, Xavier Clemente-Casares1,2, Jun Yamanouchi2, Lola Mulero-Perez1, Trond Aasen1,3, Angel Raya1,3,4, and Juan Carlos Izpisúa Belmonte1,5

1Center of Regenerative Medicine in Barcelona, Dr. Aiguader 88, 08003 Barcelona, Spain.

2Julia McFarlane Diabetes Research Centre, Department of Microbiology and Infectious Diseases, and Institute of Inflammation, Infection and Immunity, Faculty of Medicine, The University of Calgary, 3330 Hospital Dr. N.W., Calgary, Alberta T2N 4N1, Canada.

3Networking Center of Biomedical Research in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN).

4Institució Catalana de Recerca i Estudis Avançats (ICREA).

5Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Rd., La Jolla, California 92037, USA.


Objective: Human embryonic stem (hES) cells can be differentiated into pancreatic endoderm structures in vitro. The study was performed to determine whether induced pluripotent stem (iPS) cells can be differentiated into similar structures with comparable efficiency. Methods: We compared the ability of hES cells and iPS cells derived from human epidermal keratinocytes to progressively differentiate into pancreatic endoderm. Human foreskin keratinocytes were reprogrammed to pluripotency by transduction with retroviruses encoding Oct4, Sox2, and Klf4. The resulting keratinocyte-derived iPS (KiPS) cell lines and a hES cell line were subjected to a modified pancreatic endoderm differentiation protocol. Cells and embryoid-body structures derived from both hES and KiPS cells were compared at different stages of development for expression of stem cell and differentiation markers, including Sox2, Oct4, Mixl1, Brachyury, Gsc, FoxA2, Sox17, Hnf4α, Hnf1β, Nkx2.2, Nkx6.1, Hex, Isl1, Pdx1, and Slc2A, via Taqman real-time PCR, flow-cytometry, and/or immunocytochemistry. Results: hES cells and KiPS cells expressed similar levels of the stem cell factors Sox2 and Oct4. Upon differentiation, both cell types underwent remarkably similar changes in gene expression. They acquired the definitive endoderm markers Sox17 and FoxA2. Most Sox17+ and FoxA2+ cells co-expressed Hnf4α and Hnf1β, found in the primitive gut tube, a pancreas precursor. Most FoxA2+ cells were also Pdx1+, and many expressed Nkx2.2, Nkx6.1, and Isl1. Conclusion: Keratinocyte- derived iPS cells can be differentiated into pancreatic endoderm, and the efficiency of this process is comparable to that seen for hES cells. Thus keratinocytes have the potential to serve as a source of patient-specific pancreatic endoderm for transplantation.