动物实验,实现SIV z-bio 2021-06-28 352

　　Once established in the human body, HIV and similar simian immunodeficiency SIVs that cause AIDS usually lead to permanent infections. Antiretroviral therapy (ART) can reduce these viruses in the blood to very low levels. However, the virus is still latent in the genetic material of the infected immune cells, known as the virus reservoir. After the antiviral treatment is completed, the virus level will be restored within a few weeks. Therefore, HIV treatment today includes lifelong antiretroviral therapy. Antiretroviral therapy can significantly improve overall health and prolong life, but it can be difficult to treat and can cause toxic side effects over time.

　　The intestine is one of the earliest parts of the human body affected by HIV and SIV. During early infection, the virus targets immune cells called CD4 cells in the gastrointestinal tissues. CD4 cells use a surface protein called α-4/β-7 integrin to enter the intestine and interact with the protein MAdCAM-1 on the blood vessel cells of the gastrointestinal tissue.

　　Aftab A is from Emory University. A team led by Dr. Ansari and IH National Institute of Allergy and Infectious Diseases (NIAID), Ph.D. Anthony S. Fauci, investigated whether blocking CD4 cells from entering the gut tissue could prevent this from happening. Damage and harm. The impact on the immune system. Researchers have developed antibodies to prevent α-4/β-7 integrins from interacting with MAdCAM-1.

　　Scientists have infected 18 rhesus monkeys with SIV. Five weeks later, the animal started a 90-day ART course. Nine weeks after infection, the animals began to receive antibody injections every three weeks. Eleven people received the study antibody, and the other 7 received the placebo antibody. Three of the 11 monkeys developed an immune response to the study antibody and were therefore excluded from further studies. The remaining 15 animals stopped all treatments 32 weeks after infection.

　　ART In the third week of treatment, all monkeys completely suppressed SIV. Within 2 weeks of stopping the drug, the SIV of all 7 control animals returned to high levels. SIV returned temporarily, and 6 of the 8 monkeys treated with the study antibody were suppressed. The other two viruses never rebounded. Eight monkeys failed to detect SIV in blood and intestinal tissues within 23 months. do not know yet

　　The working principle of antibody therapy. The treated monkeys supplemented their CD4 levels. They also have other obvious immune changes. For example, some therapeutic animals have developed antibodies against key regions of gp120, which is a protein required for HIV and SIV to grab and invade CD4 cells.