The HIV virus is a "slippery customer" and always tries to evade the effect of human antibodies, say researchers who suggest that tweaking an antibody could help develop an effective vaccine against HIV.
Researchers were able to identify how the HIV virus evolves to evade or 'escape' the effect of human antibodies like the ADCC, or antibody-dependent cell-mediated cytotoxicity. ADCC is an immune response in which antibodies, by coating target cells, makes them vulnerable to attack by immune cells.
Study co-author Stephen Kent, professor at the University of Melbourne, said ADCC antibodies have been strongly implicated in protection from HIV in several trials, but their action was poorly understood, reports the journal Proceedings of the National Academy of Sciences.
"These results show what a slippery customer the HIV virus is, but also shows that these ADCC antibodies are really forcing the virus into changing . . . that cause it to be weaker," he said.
"It also implies that if good ADCC antibodies were available prior to infection, via a vaccine, we might be able to stop the virus taking hold. This is the holy grail," Kent said, according to a Melbourne statement
The team led by Ivan Stratov and Prof Kent employed a novel technology their lab developed to find where ADCC antibodies were attacking the virus. They then looked at how the sequence of the virus had mutated over time to avoid the immune response.
"There is an urgent need to identify effective immunity to HIV and our studies suggest ADCC responses supply significant immune pressure on the virus," said Stratov, a clinician and researcher.
The group is now working on designing HIV vaccines to induce ADCC antibodies that make it more difficult for the virus to escape.