Scientists from the American Salk Institute for Biological Research, together with Chinese colleagues from the Kunming University of Science and Technology in Yunnan, have created chimeric human and monkey embryos for the first time.
Previously, attempts to create such chimeras ended in vain, because human cells in such embryos did not take root well.
The success of the new experiment was that the authors created a new technology that made it possible to maintain the life of chimeric monkey embryos outside their body for a long period of time.
The formation of chimeras with non-human primates more closely related to humans on an evolutionary scale than any previously used species will provide a better understanding of whether there are barriers to hybrid formation and whether there are ways to overcome them.
Juan Carlos Izpisua Belmonte, Professor of the Gene Expression Laboratory of the Salk Institute
On the sixth day of existence of ex vivo Macaca fascicularis monkey embryos, the authors introduced into each of them 25 human stem cells from an induced pluripotent cell line. These cells can participate in the formation of both embryonic and extraembryonic tissues.
On the sixth day of the existence of Macaca fascicularis, biologists injected into each of them 25 human stem cells from an induced pluripotent cell line. Such cells can participate in the formation of both embryonic and extraembryonic tissues. A day later, human cells were found in 132 embryos, after 10 days 103 chimeric embryos still continued to develop, and only three chimeras remained alive by the 19th day.
Scientists hope that such chimeric embryos can be used for research that is ethically problematic in humans.
The authors are going to find out in the near future what exactly prevents human cells from dividing in hybrid embryos.