Human skin recreated from stem cells
A French team has succeeded in recreating the together an epidermis, the superficial layer of the skin, from human embryonic stem cells, a first that could find a rapid application in the treatment of burn victims.
For several years, doctors have been using cell therapy to treat burn victims: they reconstitute skin from a small sample taken from the patient himself. The problem comes from the time needed to cultivate a sufficient area of epidermis (three weeks), during which the burn is unprotected, with risks of infection, dehydration ... Techniques have been developed to fill this period of time. waiting, but they are far from optimal.
It is this period that the work of the team led by Marc Peschanski (Institut I-Stem), published in the journal The Lancet dated Saturday, has targeted, explained the researcher to AFP.
The first step was to obtain skin cells (keratinocytes) from human embryonic stem cells, both capable of differentiating into all types of human cells and reproducing indefinitely.
From these keratinocytes, they then succeeded in reconstructing "in vitro" an epidermis with its various layers, including the stratum corneum, the most superficial one. A study conducted in collaboration with a biotechnology company specialized in the skin made it possible to verify "that it was a perfectly normal epidermis".
The last step was carried out with Spanish researchers mastering a technique of implantation on the mouse. The epidermis reconstituted in the laboratory was thus grafted onto mice.
"We waited three months and the human skin has been renewed three times, since it is renewed every month completely. We made human skin, "said Professor Peschanski.
To switch to an application in humans, now remains to achieve a transfer of technology. "We started working on it, it will take a little while, because we have to validate everything, but it's not science anymore, it really becomes technical application," said the researcher. .
He tables, "if everything goes well", on a passage in the man "for the end of 2011". "But knowing that it's a calendar hanging from a number of threads that can be cut at any time."
Several researches on embryonic stem cells are now coming to an end, close to the transition to the application on humans:
The Californian company Geron has already received authorization in the United States to carry out a clinical trial to treat spinal cord injuries.
Another American company, Advanced Cell Technology, has filed a license application for trials on patients at risk of losing their eyesight due to Stargardt's disease.
A third is working on a diabetes treatment.
In France, Philippe Menasché tests on the monkey a treatment of infarction.
Marc Peschanski is also working on induced pluripotent cells (iPS), resulting from the reprogramming of the nucleus of differentiated adult cells. The I-Stem Institute was created by the National Institute of Health and Medical Research (Inserm) and the French Association against Myopathies (AFM), organizer of the Telethon.