Friday, March 20, 2009

iPS indistinguishable from ESC (so what is the ‘gold standard’ and what is the fool’s gold?)

Here is yet another example of the iPS technology that has transformed stem cell science since November 2007: taking an adult cell (this time from a blood sample) and turning it into the exact equivalent of the pluripotent stem cells extracted from embryos (which become dead embryos in the process).

This report, published 18th March, is useful for listing the strict and comprehensive criteria by which the iPS cell is tested against ESC properties. In every way, they are identical. The same. No different.

There is much chatter about still needing ESCs as 'the gold standard' to test iPS cells against. This is the current residual argument scientists have to justify the dying science of embryo exploitation. But it is increasingly a standard of fool's gold. ESCs show no advantage over iPS and plenty of disadvantages: because they come from IVF embryos they do not match the patient, whereas iPS exactly match the patient; if they were to come from cloned embryos (and remember nobody has ever got a single ESC from a cloned human embryo, despite the millions spent) then they still, dear reader, do not match the patient – as cloning still incorporates foreign DNA from the mitochondria of the donor egg.

Smart private 'gold' is not going to chase the fool's alternative of ESCs from IVF embryos or from cloned embryos. Only dumb 'public' gold will do that – while certain scientists continue to dupe politicians about the 'gold standard' of ESCs…

And so to the key paragraph of this article:

Generation of induced pluripotent stem cells from human blood Yuin-Han Loh, Suneet Agarwal, In-Hyun Park, Achia Urbach, Hongguang Huo, Garrett C. Heffner, Kitai Kim, Justine D. Miller, Kitwa Ng, and George Q. Daley*

Blood First Edition Paper, prepublished online March 18, 2009; DOI 10.1182/blood-2009-02-204800.

"Blood derived human iPS cells are indistinguishable from human embryonic stem (ES) cells with respect to morphology, expression of surface antigens and pluripotency-associated transcription factors, DNA methylation status at pluripotent cell-specific genes, and the capacity to differentiate in vitro and in teratomas. The ability to reprogram cells from human blood will allow the generation of patient-specific stem cells for diseases in which the disease-causing somatic mutations are restricted to cells of the hematopoietic lineage."