Research abstract

Letter abstract


Nature Biotechnology 27, 1033 - 1037 (2009)
Published online: 11 October 2009 | doi:10.1038/nbt.1580

Live cell imaging distinguishes bona fide human iPS cells from partially reprogrammed cells

Elayne M Chan1,2,10, Sutheera Ratanasirintrawoot1,3,4,10, In-Hyun Park1,2,10, Philip D Manos1,3, Yuin-Han Loh1,2, Hongguang Huo1,3, Justine D Miller1,3, Odelya Hartung1,3, Junsung Rho1, Tan A Ince5, George Q Daley1,2,3,6,7,8,9 & Thorsten M Schlaeger1,3,6

Top

Somatic cells can be reprogrammed into induced pluripotent stem (iPS) cells by enforced expression of transcription factors. Using serial live imaging of human fibroblasts undergoing reprogramming, we identified distinct colony types that morphologically resemble embryonic stem (ES) cells yet differ in molecular phenotype and differentiation potential. By analyzing expression of pluripotency markers, methylation at the OCT4 and NANOG promoters and differentiation into teratomas, we determined that only one colony type represents true iPS cells, whereas the others represent reprogramming intermediates. Proviral silencing and expression of TRA-1-60, DNMT3B and REX1 can be used to distinguish the fully reprogrammed state, whereas alkaline phosphatase, SSEA-4, GDF3, hTERT and NANOG are insufficient as markers. We also show that reprogramming using chemically defined medium favors formation of fully reprogrammed over partially reprogrammed colonies. Our data define molecular markers of the fully reprogrammed state and highlight the need for rigorous characterization and standardization of putative iPS cells.

Top
  1. Division of Pediatric Hematology/Oncology, Children's Hospital Boston and Dana-Farber Cancer Institute, Boston, Massachusetts, USA.
  2. Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA.
  3. Stem Cell Program, Children's Hospital Boston, Boston, Massachusetts, USA.
  4. Biological and Biomedical Sciences, Harvard Medical School, Boston, Massachusetts, USA.
  5. Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts, USA.
  6. Harvard Stem Cell Institute, Cambridge, Massachusetts, USA.
  7. Howard Hughes Medical Institute at Children's Hospital Boston, Boston, Massachusetts, USA.
  8. Division of Hematology/Oncology, Brigham and Women's Hospital, Boston, Massachusetts, USA.
  9. Manton Center for Orphan Disease Research, Children's Hospital Boston, Boston, Massachusetts, USA.
  10. These authors contributed equally to this work.

Correspondence to: George Q Daley1,2,3,6,7,8,9 e-mail: george.daley@childrens.harvard.edu

Correspondence to: Thorsten M Schlaeger1,3,6 e-mail: schlaeger@enders.tch.harvard.edu.