What immune response should a vaccine elicit to prevent HIV infection? Two studies published online today bring scientists closer to answering this question by identifying previously unrecognized attributes of antibodies that appear to have reduced the risk of HIV infection in the only clinical trial to show efficacy, albeit modest, of an experimental vaccine regimen in people.
of the results of that trial, known as RV144
, suggested that antibodies to sites within a part of the HIV envelope called V1V2 correlated with reduced risk of HIV infection. These antibodies belong to a class called immunoglobulin G, or IgG. The new studies by two independent laboratories both found that only one subclass of V1V2-directed IgG antibodies—the IgG3 subclass—is associated with antiviral responses linked to the reduced risk of HIV infection seen in RV144. The experiments were led by Georgia D. Tomaras, Ph.D., of the Duke Human Vaccine Institute, and Galit Alter, Ph.D., of the Ragon Institute, with funding in part from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health ...
Read the full article: http://www.niaid.nih.gov/news/newsreleases/2014/Pages/RV144Correlate.aspx