Discovery of two antibodies could move AIDS vaccine development forward

Sep 5 2009

Scientists from Scripps Research Institute on Thursday announced they have discovered and isolated two antibodies "with the ability to neutralize [or block the action of] many strains of the AIDS virus, a discovery that might help create a long-sought vaccine against the deadly disease," Bloomberg reports. "Working with doctors and clinics in Thailand, Australia, the U.S., the U.K. and especially Africa, where two-thirds of the world's infected people live, the group collected blood samples from 1,800 people who had been infected with HIV for at least three years without developing symptoms," according to Bloomberg (Waters, 9/3).

"Such individuals are most likely to produce antibodies that interfere with the replication of the virus," the Los Angeles Times reports. The research, published online Friday in the journal Science, shows that the scientists "isolated two antibodies, called PG9 and PG16, from one African patient" that "were able to block the activity of about three-quarters of the 162 separate strains of HIV they tested it against" (Maugh, 9/4).

Nature News adds: "The two newly discovered HIV-specific antibodies are the first to be identified in more than a decade and the first from an HIV carrier living in the developing world, where most new HIV infections occur" (Dolgin, 9/3).

"While the new antibodies are not the first of the so-called broadly neutralizing antibodies that have been isolated from HIV-positive patients, they appear, at least in the lab, to be 10 times more effective at disarming the virus than earlier versions," TIME writes. Additionally, "[t]hey are also effective against a broad array of HIV strains that span nearly every continent, from Europe and North America to Asia and Africa" (Park, 9/3). Though "[t]he antibodies are produced naturally by a minority of people infected with HIV," scientists "believe they can create an effective vaccine if they are able to stimulate the body to produce such … antibodies before exposure to HIV," Agence France-Presse writes (9/3).

The Wall Street Journal notes: "Any potential vaccine is still a long way off, however. Researchers now have to work out how these antibodies bind to HIV, the virus that causes AIDS, and use that property as the basis for a vaccine. As a result, animal or human trials are likely to be years away" (Naik, 9/4).

"'The findings themselves are an exciting advance toward the goal of an effective AIDS vaccine because now we've got a new, potentially better target on HIV to focus our efforts for vaccine design," said Wayne Koff of the International AIDS Vaccine Initiative, the group which sponsored the study, Reuters reports (Fox, 9/3). Scientists have already begun follow-up studies "to screen for more broadly neutralising antibodies," New Scientist reports (Coghlan, 9/3).

The Economist examines how despite gains in HIV/AIDS treatment and prevention, years of research has brought "the field no nearer to what is really needed—a vaccine that will stop people getting infected in the first place." As the magazine notes, "[t]he last big vaccine trial, known as STEP, ended in failure in 2007." Though there is work to be done to better understand more about the newly identified antibodies, the magazine refers to the findings as "a revival of hope" for the field (9/3).

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