Washington: Many would get scared at the mere mention of somebody suffering from HIV. But scientists claim that they have discovered the exact way of how an HIV-related virus Evade human antibody.

An international team says that the latest insights into immunity to HIV could help develop a vaccine to build antibodies' defenses against AIDS.

By investigating the action of the human antibodies called ADCC, in people with HIV, the scientists were able to identify that the virus evolves to evade or "escape" the antibodies.

Lead scientist Prof Stephen Kent of the University of Melbourne said ADCC antibodies have been strongly implicated in protection from HIV in several vaccine trials but their action was poorly understood.

He said: "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, in ways that cause it to be weaker.

"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."

In their research the scientists analysed blood samples of people with HIV and found their virus had evolved to evade or "escape" the ADCC antibodies against HIV they are making to try to control their virus.

The team employed a novel technology developed in their laboratory 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 team member Dr
Ivan Stratov.

The group is now working on designing HIV vaccines to induce ADCC antibodies that make it more difficult for the virus to escape.

The findings have been published in the latest edition of the 'PNAS' journal.

Agencies