A new study by Los Alamos National Laboratory and University of Pennsylvania (U. Penn) scientists, together with colleagues from many other institutions, defines previously unknown properties of transmitted HIV-1, the virus that causes AIDS. The viruses that successfully pass from a chronically infected person to a new individual are both remarkably resistant to a powerful initial human immune-response mechanism, and blanketed in a greater amount of envelope protein that helps them access and enter host cells. These findings will help inform vaccine design and interpretation of vaccine trials, and provide new insights into the basic biology of viral/host dynamics of infection. During the course of each AIDS infection, the HIV-1 virus evolves within the infected person to escape the host’s natural immune response and adapt to the local environment within the infected individual. Because HIV evolves so rapidly and so extensively, each person acquires and harbors a complex, very diverse set of viruses that develops over the years of his or her infection. Yet when HIV is transmitted to a new person from his or her partner, typically only a single virus from the diverse set in the partner is transmitted to establish the new infection. The key discoveries here are the specific features that distinguish those specific viruses which successfully move to the new host, compared with the myriad forms in the viral population present in a chronically infected individual. “The viruses that make it through transmission barriers to infect a new person are particularly infectious and resilient,” said Los Alamos National Laboratory scientist Dr. Bette Korber.
Login Or Register To Read Full Story