Researchers from Oregon report that they have successfully derived embryonic stem cells (ESCs) from a blastocyst created through somatic cell nuclear transfer. If confirmed, this would be a world first and could potentially lead to the creation of human ESCs through cloning.
While details of the new research – led by Shoukhrat Mitalipov and performed at the Oregon National Primate Research Center – will be unavailable until the work is published in the journal Nature, his past work may provide some indication of what to expect. (Given the fraud of Hwang Woo-Suk, who came out of nowhere, one can't be too careful.)
A 2002 Biological Reproduction paper demonstrated that nuclear transfer monkey embryos (using non-embryonic donors) were comparable with IVF embryos through the 8-cell stage, but not thereafter. An October 2006 Human Reproduction paper reported that Mitalipov's team generated blastocysts at a rate of almost one in four (24.4 percent) using a modified nuclear transfer technique with fetal skin donor material. (Adjusting for various factors, the 2006 paper suggested that one "normal" blastocyst, from which to obtain ESCs, could be created with the number of eggs normally released in one menstrual cycle.)
Where could this new research lead?
The Independent in the United Kingdom reports that Mitalipov has successfully cloned embryos using donor material from an adult monkey, using a new technique to transfer donor nuclei into the egg. They go on to say that Mitalipov told scientists at a June meeting that he had (at that point) obtained two stem cell lines from 20 cloned embryos, but failed to mention a success rate or whether the obtained stem cell lines came were created with the help of an adult donor.
A published report in the hopefully near future should answer whether the team succeeded in improving the nuclear transfer technique to a point where ESCs can be obtained from adult donor material or just to where blastocysts could be created that may one day allow ESCs to be extracted.
I would bet on the latter given Mitalipov's past work, with derivation of ESCs from a cloned embryo created with fetal tissue being the bonus. There could be more, but only time will tell.
Cloning: a giant step [The Independent]
Image: Wikipedia
