Scientists for quite some time (and sometimes even quitesuccessfully) try to bring out the chimeras. Without going into details, chimeras are organisms made up of genetically different cells. If it is even simpler, then the body looks like a creature of one species (or looks very similar to it), but at the cellular level, such an animal has cells of another species. And, as the editors of New Science magazine reports, not so long ago, a group of Chinese researchers was able to first bring out a hybrid of pigs with cells of monkey primates.
How to create a chimera?
Scientists from the State Stem Laboratorycells and reproductive biology in Beijing "crossed" an ordinary pig with primates of the genus Cynomolgus. The study was led by Dr. Tang Hai. He and his colleagues genetically modified the cell culture of Cynomolgus monkeys so that they could produce a fluorescent protein called GFP. This allowed researchers to track the cells and how they develop during the formation of the body. Then they took these modified cells and introduced them into pig embryos five days after fertilization.
This is the first successful hybrid cultivation experience.pigs and monkeys, says Dr. Tang Hai. More than 4,000 embryos were implanted in sows. As a result, ten piglets were born, of which two were chimeras.
Unfortunately, successfully born hybrids died induring the week. Scientists have found that chimeric piglets have a huge amount of tissue - including in the heart, liver, spleen, lungs, and even the skin consisted of monkey cells, but their proportion was low: from one in 1000 to one in 10000.
It’s not clear why the pigs died, but sincenon-chimeric pigs also died, the team suspects that this is due to the process of in vitro fertilization (IVF), and not chimerism. IVF does not work as well in pigs as in humans and some other animals. Therefore, you need to look for ways to fix this.
Now a team of experts is trying to createhealthy animals with a higher proportion of monkey cells. If this succeeds, the next step will be an attempt to create pigs in which one organ will almost entirely consist of primacy cells.
Why create chimeras?
The ultimate goal of all research of this kindis the cultivation of human organs in animals for transplantation. But the results show that there is still a long way to go to achieve this.
For example, something similar has already been achieved yetin 2010. Then the Japanese scientist Hiromitsu Nakauti, now working at Stanford University in California, created rat pancreas mice by genetic modification of mice so that their own cells could not develop into the pancreas and this organ would “belong” to a different species.
See also: People-chimeras: the era of "post-nature" will be strange and beautiful.
In 2017, the team of Juan Carlos IspisuaBelmonte from the Salk Institute in California created pig and human chimeras, but only then only one cell per 100,000 was human, and for ethical reasons, embryos were allowed to develop only for one month. This is due to the fact that, according to one of the theories, the brain of a chimera can be “partially human” and, therefore, possess human consciousness. That is why Hui and his team used monkeys, not human cells. Do you consider such experiments ethical? Write your opinion in our chat in Telegram.
Given the extremely low chimericefficiency ”and the death of all animals, I actually find it rather discouraging. - Comments on the results of the Chinese team, biologist Paul Knopfler from the University of California at Davis, dealing with the use of stem cells.
However, a number of scientists still do not believe thatsomeday it will be possible to grow in the body of another species organs suitable for transplantation to humans. Nevertheless, it makes sense to continue the study of this approach, along with others, until the optimal way to create organs for transplantation is found.