As you know, animals whose organs can be transplanted to a man almost without fear, are not our closest relatives, the primates, and pigs. The truth that transplant organs has a big drawback: the presence in pigs is extremely dangerous for human retroviruses. But a group of scientists from the USA managed to overcome this problem and to “humanize” animals, making their organs suitable for transplant.
It is fair to say that science knows of successful attempts to transplant organs from animals to humans, but the training required to conduct such operations extremely costly and difficult. Know-how of American specialists, according to the Agency RIA “Novosti” with reference to the journal Science, greatly simplifies the procedure. According to one of the study’s authors, George Church of Harvard University,
“The pig organs are similar to their human counterparts in size and operating principles, and they can be grown in large numbers for transplantation. Now this is not done for two reasons – because of an incompatibility between pigs and humans at the level of the immune system and the possibility of human infection by retroviruses that are present in the DNA of the animal.”
A large-scale study was launched 2 years ago, when Mr. Church with his colleagues learned how to edit and delete parts of the DNA in the cells. It is to such forms are the so-called PERV-a proviruses that coexist with pigs for hundreds of thousands of years. They do not pose a threat to the animal, but, penetrating into the human body, together with a transplanted organ can cause serious health problems and complications.
The main problem of these viruses is that they are not amenable to traditional methods of therapy, as embedded in pig DNA and the genome of the animal itself contains copies of the virus. To help scientists come editor CRISPR/Cas9. With the help of professionals cut out from the genome of the pig all 62 version of the PERV-a virus. Did the cells and organs of animals “clean” and allowed to avoid pre-existing complications.
In the course of work on the virus, scientists have developed a new technique of input CRISPR/Cas9 in cells of pigs, which prevent their “self-destruct” after a mass delete a large number of DNA, as well as to overcome many other problems associated with editing of the genome of the embryos.
Implantiruut “edited” the embryos into the womb of surrogate mothers, the scientists obtained three dozen healthy piglets whose organs were completely cleared from PERV. But scientists don’t stop: the experts aims to eliminate another important drawback associated with the transplantation: suppression of human immune system transplanted organs. If scientists will be able to create pigs whose organs will not be perceived by the immune system of the recipient as something alien, it may be a real breakthrough in medicine and transplantation.
First grown pigs whose organs can be transplanted to a human
Vladimir Kuznetsov