Every once in the while a
research paper is published that really astounds you. Such is the recent pair
of NATURE papers from Obokata et al
(1). What is described is an extremely
simple way to convert mature differentiated cells to stem cells by exposure to
stresses such as low pH. This process is called Stimulus-Triggered Acquisition
of Pluripotency (STAP). The STAP cells seem to be able to contribute to all
tissues in chimeric mice and to be passed through the germ line, the hallmark
of truly pluripotent stem cells. Interestingly, the STAP cells can contribute
to both embryonic and placental tissue. This is unlike iPS cells, whose
pluripotency is induced by expression of a small set of transcription factors,
and which can only contribute to embryonic tissue.
Assuming that it can be
extended to human cells, this amazing result has numerous potential
implications. First of all it calls into
question the much-touted concept of cancer stem cells. Perhaps these are simply
cells that have been converted to stemness by the harsh tumor environment (low
pH, low O2). Second, by making stem cell production far easier the
STAP approach will hasten implementation of stem cell based therapies in
various diseases. But perhaps most interesting consequence may be in the
nascent field of human enhancement. By virtue of being able to generate large
numbers of stem cells from an individual’s own cells it may be possible to
retard the accumulation of senescent cells that have been implicated as a key
factor in the tissue degeneration that accompanies increasing age (2). So are STAP cells the fountain of youth? We
shall see.
(2) Baker, D.J., Wijshake, T., Tchkonia, T., LeBrasseur,
N.K., Childs, B.G., van de Sluis, B., Kirkland, J.L. and van Deursen, J.M. (2011)
Clearance of p16Ink4a-positive senescent cells delays ageing-associated
disorders. Nature, 479, 232-236
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