Induced pluripotent stem cells - current progress and their potential for regenerative medicine
Summary
Both human and mouse somatic cells were reported to be reprogrammed to pluripotent stem
cells (iPS cells) upon viral transduction with a defined set of transcription factors including
OCT4, SOX2, KLF4, c-MYC, Nanog and LIN28 in different combinations. Reprogramming
of somatic cells to pluripotency enables the derivation of patient-specific pluripotent cells that
have great potential for regenerative therapies, studying (embryonic) development and the
differentiation process towards different cell lineages. Also, cell lines can be generated to
model genetic diseases and derivatives of these could be used in drug screens and toxicology
testing. The use of iPS cells for modeling the development of genetic disorders and their use
for transplantation therapies after modifying genetic defects have been successfully shown in
several reports such as in sickle cell anemia, diabetes and Parkinson’s disease. In contrast to
previous reprogramming methods, the derivation of iPS cells circumvents the use of oocytes
or embryonic material. However, the use of oncogenes and integrating viruses for generating
iPS cells should be avoided since this increases the risk of tumor formation. The recent
findings that mouse and human iPS cells can be derived with non intregrating vectors and the
removal of exogenous reprogramming factors after reprogramming increases the possibility of
the future use of iPS cells for clinical applications.