Release date: 2016-04-11 - In the United States alone, approximately 22% of patients awaiting human organ transplants die each year, and human organs for organ transplantation are in short supply. Scientists have long hoped to be able to replace them with animal organs, and the pig's organs seem to have great application prospects. In a long-term trial conducted by the NIH in the United States, the researchers transplanted the heart of the pig to the abdomen. They published data on the survival of five transplanted pig hearts. One of the hearts maintained a healthy state for nearly three years in the sputum. Although these data are not sufficient to illustrate the feasibility of clinical trials, this study continues to provide some encouraging evidence for cross-species organ transplantation. Dr. Muhammad Mohiuddin, who led the study, said: "In the past, people thought that such experiments were crazy and meaningless. But through these experiments, we realized that cross-species organ transplantation for humans can be achieved." Simply transplanting an organ from one animal to another immediately causes a strong attack by the host immune system. In some early cross-species transplantation experiments, organs survived for only a few minutes. There is a molecule called α-1,3-galactoside transferase on the surface of porcine vascular cells that can cause antibodies to be produced in the human body, which in turn leads to thrombosis. Although scientists built genetically engineered pigs that lacked the gal gene in 2001, pig organs can only survive for months in ticks and other non-human primates, and transplanted animals need to suppress the immune system through drugs. To avoid rejection of foreign organs, but at the same time make them susceptible to infection. In this study, the researchers conducted a number of targeted drug screenings in the hope of finding drugs that would protect the transplanted organ without destroying the immune system. One of the most promising is an antibody that binds to CD40, which the researchers used in conjunction with the blood-diluted drug heparin to receive five sputum from a genetically engineered pig-derived heart transplant. These donor pigs not only lacked the gal gene, but also expressed two other human genes to help inhibit thrombosis. In this experiment, the researchers did not remove the heart of the cockroach itself, but connected the porcine heart to the blood vessels in the abdomen, thus avoiding complicated heart surgery and studying immune rejection. These transplanted hearts survive longer, but have they developed immune tolerance? To answer this question, the researchers withdrew the anti-CD40 antibody and found that once the antibody was stopped, the immune system of the cockroach began to reject the pig's heart. One of the cockroaches was immunosuppressed for one year before stopping the drug. The porcine heart transplanted in vivo can survive under the action of low doses of drugs, indicating that low doses of immunosuppressive drugs are still effective, but this also means This transplantation method still requires immunosuppression for life. In addition, some experts have suggested that transplanting the heart to the abdomen can not survive. It does not mean that the heart can work normally. It is still a big problem to transplant it to the chest to truly replace the original heart. The relevant research results are published in the international academic journal Nature Communication. Source: Bio Valley Foot and leg massager Foot and leg massager Shenzhen Jie Zhong Lian Investment Co., Ltd. , https://www.szmeizon.com