Are we closer to an AIDS vaccine?

AIDS vaccine target discovered

(RxWiki News) For the past 30 years, scientists have had no success developing a vaccine for AIDS. Their track record may change with the discovery of a powerful new anti-HIV antibody.

The antibody can break through a shield around HIV's surface protein previously thought to be impenetrable. “If we are able to teach humans how to make this antibody using vaccations, we'll be able to block HIV infections on a global scale,” said Dr. Jean-Philipe Julien, a scientist at the Scripps Research Institute who contributed to the research.

"Speak with your doctor regarding new AIDS vaccines."

The antibody was isolated in the blood of one individual who contributed a sample to the study. Antibodies are proteins made by the immune system in order to fight pathogens, viruses and bacteria that enter the body. This anti-HIV antibody, called PGT 128, has the ability to bind to a protective shield on the virus' surface, and then actually break through.

“What is special about this research is that we're able to see how one antibody, isolated from a very rare patient, is able to interact with a protein on the surface of the virus,” Dr. Julien explained. PGT 128 can neutralize 70 percent of the HIV viruses that are circulating around the world, he said. It blocks their ability to infect more cells.

HIV can mutate quickly, which has been a central challenge for AIDS vaccine development. But the antibody's strength is that it attaches to a part of the virus that is common across many strains.

“This research identifies, at the atomic level, how the antibody interacts with the virus. That's the major accomplishment,” said Dr. Julien. “As to vaccine design, this gives us clues as to how to engineer molecules that will be part of the vaccine.”

Now that scientists know how PGT 128 manages to attach and break through HIV's protective shield, they can mimic its structure to create a vaccine. Such a vaccine would have powerful implications for a highly infectious epidemic that infects millions each year.

The research was published in October 2011, in Science Express. It was supported by the International AIDS Vaccine Initiative, National Institutes of Health, the U.S. Department of Energy, the Canadian Institutes of Health Research, the UK Research Councils, the Ragon Institute, and other organizations.

Review Date: 
October 14, 2011