This new approach to HIV prevention—called Vectored ImmunoProphylaxis, or VIP—is outlined in the November 30 advance online publication of the journal Nature.
Traditional efforts to develop a vaccine against HIV have been centered on designing substances that provoke an effective immune response—either in the form of antibodies to block infection or T cells that attack infected cells. With VIP, protective antibodies are being provided up front.
"VIP has a similar effect to a vaccine, but without ever calling on the immune system to do any of the work," says Alejandro Balazs, lead author of the study and a postdoctoral scholar in Baltimore's lab. "Normally, you put an antigen or killed bacteria or something into the body, and the immune system figures out how to make an antibody against it. We've taken that whole part out of the equation."