动物造模,HIV z-bio 2021-06-28 741

　　Scientists at the National Institutes of Health and Rockefeller University have proved that monkeys will immediately acquire two powerful anti-HIV antibodies after being infected with an HIV-like virus, allowing the immune system of certain animals to control the virus for a long time.

　　Researchers have vaccinated 13 monkeys with Simian Human Immunodeficiency Virus or SIV. Three days after vaccination, when the infection was clearly confirmed, the scientists gave each monkey an intravenous injection of two effective, broadly neutralizing HIV antibodies within two weeks. These antibodies, called 3BNC117 and 10-1074, bind to different parts of SIV, neutralize the virus and promote clearance by the immune system.

　　Antibody infusion can suppress SIV to a level close to or below the standard detection limit for up to 6 months. When the antibody level drops to a very low level, the virus rebounds, except for one animal. Then, 5 to 22 months later, the immune systems of 6 monkeys spontaneously regained control of the virus, reducing it to undetectable levels in the next 5 to 13 months. After receiving the antibody injection, the 6 control monkeys continued to maintain a healthy level of important immune cells.

　　Except for the 6 control animals, the other 4 monkeys that failed to completely control the virus had very low blood SIV levels and main immune cell levels 2-3 years after infection, and they were healthy. Therefore, according to the researchers, 10 out of 13 monkeys benefited from antibody immunotherapy. In order to be sure called

　　Whether the immune cells of CD8 + T cells play a role in the expansion and regulation of SIV, the scientists provided six control monkeys with antibodies that target and deplete these cells. When the level of CD8 + T cells drops, injection of this antibody will immediately increase the amount of SIV in the monkey's blood. The researchers concluded that after injection of therapeutic antibodies, CD8 + T cells can control SIV replication.

　　A study is underway to test whether monkeys can control SIV by waiting for a therapeutic antibody infusion within 2-6 weeks after SIV infection (usually close to the time to diagnose HIV infection).