U.S. researchers said they have grown animal? Chimera! 85% is a sheep, and 15% — people. Externally, it will quietly: head, body, legs and tail of it are the same as ordinary sheep, but the liver is mainly composed of human cells.
Implementation of a long-standing scientific ideas required of a professor of the University of Nevada Esmail Zanjani seven years. The project was conceived as a search for an alternative source of organs for transplant to sick people.
The thought-men as living containers for growing bodies need is not new. It is based on the idea of the miraculous properties of stem cells.
In words, the algorithm for obtaining a healthy liver to replace the patient is simple. Taken from human stem cells transplanted sheep embryos, and came to being in two months lamb already has a healthy liver. The liver is removed and transplanted human. Theoretically it is possible to grow other organs.
Animal rights activists, meanwhile, fear that if the cells are mixed together, you could end up fusing the cell, creating a hybrid which would have the features and characteristics of both man and sheep. But Professor Zanjani said: "Transplanting the cells into fetal sheep at this early stage does not result in fusing at all."
Recall that the American and Chinese scientists in experiments with human stem cells has already achieved remarkable results. Researchers from Shanghai in 2003 splice human cells and rabbit eggs. These embryos for several days, developed in vitro, and then the scientists have received the stem cells.
A year later, the Minnesota Mayo Clinic researchers have created pigs with human blood.
All these creatures, called scholars "chimeras" after the Greek mythical creature with a lion's head, goat's body and tail of the snake, will help reveal some secrets of anatomy and find new ways to treat disease.
The first breakthrough in the creation of chimeras refers to the beginning of the nineties. Then biologist Evan Balaban transplanted cells of the human brain to chickens. Birds showed the unique ability to develop, gave leaping trills that proved — the exchange of skills between different living things are.
In 2004, Irving Veyssmanu researcher at Stanford University managed in much the same way to bring the mouse to the immune system, almost identical to the human. In mice? Chimeras can now test new drugs against AIDS, which affects not ordinary mice.
Later, scientists injected in a mouse embryo human nerve cells, and to light a small creature, which, according to Weissman, the mental capacities of a one percent corresponded to man.
Now the scientists are going to put in mouse brain cells a person affected with Parkinson's disease, and to investigate the disease. In my dreams, the researcher — the birth of the mouse brains which is one hundred percent would correspond to a human.
Scientists believe that the more similar to the human animal is, the more relevant research model will be it for testing drugs and other needs. Attractive as possible to grow "spare parts" for transplantation in humans.
In addition, monitoring of the aging of human cells and their interaction in vivo may lead to discoveries of new treatments.
However, the creation of chimeras brings to life a series of questions: What kind of new humanoid combination obtained as a result, and for what purposes it is permissible to use, and with which it is not? And at what point it should be considered a person?
William Cheshire, a professor of neurology at the Mayo Clinic in Jacksonville, Florida, said that the study, in which human and animal cells are combined to study the functions of cells, are acceptable.
Ethical boundary, according to him, is where a human embryo is destroyed to obtain cells, or when the study is a new body — poluchelovek and semi-animal.
"We must be careful not to violate the integrity of human life and fauna, for which we are responsible, — says Cheshire. — Studies in which created human-animal chimeras, risk to weaken the fragile ecosystems, endanger health and undermine the integrity of the species. "
Category: Scientists, experts, science