American scientists report unprecedented success in the integration of living human cells into the organisms of other animals. In particular, they managed to create the most perfect hybrid of a mouse and a person to date - something that is impossible in ordinary nature. Such chimeras are extremely important and necessary for science, but they are not at all spectacular from the point of view of, for example, cinema - instead of nightmarish monsters, ordinary-looking rodents grow in cages.
To be precise, not a single mouse-human hybrid has ever been grown to adulthood; all embryos, including the most successful ones, are destroyed on the 17th day of life. Not because of safety requirements - scientists are sure that such creatures are no more dangerous than an ordinary mouse. There is simply no point in wasting resources and time on an intermediate result - when the content of human cells in the mouse body is only 0.1%, it is of no practical interest.
And even today's record 4% of human cells in a mouse body is just a reason for the personal pride of researchers. The method itself is much more interesting - scientists managed to calibrate human stem cells, achieving approximately the same growth rate as mouse cells. This made it possible to carry out mutual integration, but it did not lead to the desired result. Human cells partially settled in the liver and hearts of mice, but most of them simply turned into red blood cells.
The very fact of the presence of human cells in the body of a mouse does nothing, for science it is important to obtain entire organs, systems, such as the circulatory or respiratory system. To set up experiments, use human mice as the optimal laboratory model. On the one hand, this makes it possible to study the problems of treating human organs, on the other hand, hybrids are bred and exploited like ordinary mice, in large quantities and cheaply.