Article URL: https://www.lji.org/news-events/news/post/new-hiv-vaccine-shows-unprecedented-success-in-preclinical-study/ Comments URL: https://news.ycombinator.com/item?id=49083314…

LA JOLLA, CA—A new HIV vaccine developed by La Jolla Institute for Immunology (LJI), Scripps Research scientists, and IAVI has the potential to protect humans from developing HIV infection and AIDS. This HIV vaccine is the first to generate a high number of “broadly neutralizing,” virus-fighting antibodies in primates. “This feels like a huge success,” says LJI Professor and Chief Scientific Officer Shane Crotty, Ph.D., who co-led the research with Scripps Research Professor William Schief, Ph.D. “We constructed a successful vaccine from the ground up, which required a deep understanding of the immune system.” This groundbreaking research, published in Nature, is the result of 14 years of collaboration between La Jolla Institute for Immunology and Scripps Research, as part of the Scripps Consortium for HIV/AIDS Vaccine Development (CHAVD). “This has been one of those Apollo moon mission-type projects, where there is an exceptional goal and the team has to accomplish a myriad of discoveries and inventions along the way,” says Crotty. The new vaccine works by intervening in a process called B cell maturation. B cells make antibodies. Like many immune cells, B cells have an early “naive” stage before they are ready to make antibodies. B cells start to mature once they get the signal that a pathogen, such as a virus, is trying to attack. B cells see pieces of that pathogen’s molecular structure and start producing antibodies that can bind to that structure and halt infection. It can take a little while for B cells to find the right “bullseye” on a pathogen. But B cells keep trying. As they mature, B cells tweak their antibody production, refining antibody structures to bind to a pathogen in just the right, vulnerable spots. Scientists describe B cell development as a training process or bootcamp. In most cases, the body is left with a well-honed B cell army. HIV is hard to beat because it doesn’t give B cells a chance to develop effective antibodies. The first problem is that HIV disguises itself from the immune system. The virus is wrapped in an ever-shifting cloak of sugar molecules, called glycans. This lets HIV sneak undetected past human cells, which are also covered in glycans. The second big problem is that HIV mutates very quickly. “The worldwide diversity of HIV mutations is extraordinary. Even the diversity within one individual person living with HIV is dramatic,” says LJI Instructor Patrick Madden, Ph.D., who served as study co-first author with Jon Steichen, Ph.D., an institute investigator at Scripps Research.