HIV Update: Pre-Adapted HIV Transmission More Dangerous, Harder to Cure

Scientists are still far from developing a cure and vaccine for the dreaded human immunodeficiency virus (HIV) due to its high viral adaptability to a person's immune response during the life time of infection.

A new study conducted by an international team of researchers from Microsoft Research, the University of Alabama at Birmingham and Emory University reveals pre-adapted HIV can exploit "holes" in the immune response.

The study, published in the journal Nature Medicine, suggests that some spontaneous mutations of HIV can change the peptide epitopes of the virus making it nearly unrecognizable by the immune system when they are transmitted to an individual.

This kind of adaptation also makes the immune response less effective in dealing with the virus. Changes in the parts of the virus that would normally trigger an immune response can make it invisible to key components of the immune system, suggesting that there are universal holes in the immune response.

"If we can't get functional responses to those adapted epitopes in the context of natural infection, it will be quite the challenge to get responses induced by a vaccine candidate," said Dr. Eric Hunter, professor of pathology at Emory University, in a statement.

Researchers also discovered that individuals infected with pre-adapted HIV have higher risk of impaired immunogenicity, elevated viral load and accelerated CD4⁺T cell decline

With their findings, researches recommend that scientists should take into account the holes in the immune system being exploited by the pre-adapted HIV when designing a vaccine for the virus.

"To get the immune system to respond to the vaccine, you have to think about its response to the adapted form of HIV, and focus on those parts of the virus that are most difficult to undergo adaptation," Paul Goepfert, M.D., director of UAB's Alabama Vaccine Research Clinic, said in a press release.

According to the study, there are more than 50,000 of new HIV infection in the United States every year. Antiretroviral therapies have been proven to be effective in treating HIV infections, but it is still important to develop better prevention methods in decreasing the number of new infections.