Extensive scrutinizing of the broadly neutralizing antibodies produced by individuals several years into an HIV infection provided invaluable insight into the best target for HIV vaccines. Scientists from the Scripps Research Institute
(TSRI) have identified a potential weak spot on the surface of the HIV virus, and they are ready to test vaccine candidates in animal models.
The TSRI team found four antibodies that targeted the HIV V2 apex, an "attractive target" for vaccines since antibodies recognizing this site are found in 20-30 percent of HIV-infected people who develop broadly neutralizing antibodies (Immunity
). In addition, a whopping 90 percent of HIV strains produce this targetable protein, including HIV strains that infect other species. The V2 apex is an effective target for vaccine development since the proteins in this region help stabilize the HIV virus.
By duplicating and engineering the molecular structure of the targeted HIV proteins in the lab, TSRI scientists are able to create vaccines that boost the effect of broadly neutralizing antibodies in HIV-infected people that have already developed antibodies, and introduce the effect to infected people who have not.
"This study is an example of how we can learn from natural infection and translate that information into vaccine development," said Raiees Andrabi, a TSRI Research Associate.
Indeed, the TSRI team will potentially be able to give the immune system a microscopic nudge to develop the proper antibodies in response to an HIV infection.
The last piece of the puzzle while searching for the best way to neutralize HIV virus was found in the specific characteristics of two of the four antibodies found by the team that target the V2 apex. Unlike normal antibodies initially produced by B lymphocytes that need to specialize from their precursor form before finding their target, these two antibodies are able to bind to their target in their original form. Scientists from TSRI believe this quality means all HIV patients receiving vaccines made from this new technology will be able to mount the proper immune response to fight off an HIV infection.
Check out the following video to learn more about how broadly neutralizing antibodies can be used to fight HIV infections.