People rushing to start new experiments. I think it is fair to say that I have never seen such a level of excitement in a scientific department as I saw last Thursday. Maybe because I was not in the stem cell field in ’06 when Yamanaka generated pluripotent stem cells from adult cells and I was not even a scientist in ‘97 when Wilmut’s lab cloned a sheep out of an adult cell.
A new, potentially disruptive technology has arrived; one that -if reproducible- will save millions of pounds and pour previous investments down the drain. If the new method is reproducible, making patient-specific stem cells will be very cheap and very easy. You will not even need a biosafety 2 lab, a level 1 (the lowest) will do.
Haruko Obokata from the RIKEN Centre for Developmental Biology in Kobe Japan–Homeland of so many advances in the Stem Cells field- reprogramed adult cells into stem cell-like cells by simply lowering the pH of normal cell culture medium by 2 units. This treatment will kill the cells if they are left in the medium long enough but it seems to drive the cells to a naïve, undifferentiated, embryonic-like state if they are kept in there for just 30 min. The reason why environmental stress will confer these properties to mammalian cells is unknown but it is a common feature in plants.
There are of course some caveats that will have to be tackled. Obokata used mouse cells and experience tells us that reprograming human cells is much more difficult*. It is also worrying that the final product, these new pluripotent stem cells, cannot be propagated in culture indefinitely like normal stem cells; this will greatly limit their potential. However, a subsequent treatment of the cells seems to be useful in conferring the desirable self-renewal ability.
On Thursday many young lads in my department were rushing to set up their own experiments to replicate Obokata results. If they (and I) succeed, life would be much easier –and cheaper- in the stem cell field. For regenerative medicine, this could be a dream come true: up to now, producing stem cells from adults required quite a bit of genetic manipulations in a dish. Such treatments rendered the cells almost useless for transplantation due to regulatory and safety reasons. With stem cells generated without any foreign DNA or RNA or even nasty chemicals, approval for clinical trials will be much simpler.
* Some say however she’s also achieved reprogramming of human cells as well, so look out for a new paper soon.