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In the article A New Approach to Designing the AIDS Vaccine in the new issue of Time, scientists explain some of the ongoing problems inherent in creating an AIDS vaccine and, more importantly, the creative new approaches researchers are developing to fight, and possibly win, the battle against HIV.

In 1984, the HHS Secretary boldly announced that there would be an AIDS vaccine within two years. The discovery of an AIDS-causing virus (HIV), she said, was already demonstrating “the triumph of science over a dreaded disease.”

Today, 25 years and many failed attempts later, an AIDS vaccine seems as elusive as ever . . . Back at square one, a group of researchers at Rockefeller University in New York City have some new ideas — and no shortage of optimism — about how to find the holy grail of AIDS research.

In a very small fraction of people infected with HIV, the body’s immune response is able to control the virus and prevent it from progressing to full-blown AIDS. Rockefeller scientists found six such people with high levels of the antibodies that inhibit HIV proliferation and keep it from invading new cells. Taking blood samples from these special few, the researchers isolated the antibodies and set about discovering how they work.

The human immune system does not mount an attack against a single target on HIV. Instead, the body deploys many dozens of antibodies — the researchers cloned 502 antibodies from the six patients — and together they attack many different virus targets. Individually, each antibody may have little effect, but as a group — or even in lab-created packages of 20 to 50 antibodies — they seem to confer some protection against disease progression. “It’s the first time that anybody’s really looked at what the antibody response is,” says senior investigator Michel Nussenzweig, head of the Rockefeller University’s Laboratory of Molecular Immunology. “If we know what can work in nature, then the next step would be, Let’s see if we can reproduce it.”

It sounds simple. But this reverse-engineering approach, finding inspiration for new vaccines by studying HIV immunity in nature, would have been impossible back in 1984 — or, indeed, until just a few years ago. Too little was known about the virus’s structure or about the human immune system in general.

. . . the search for an AIDS vaccine has been thwarted over and over by the tricky, unexpected nature of HIV, whose behavior is only now coming to be understood . . . One major problem with HIV is that it mutates in the body very quickly, so the immune system doesn’t always recognize the virus as something it’s encountered before. This is a stumbling block for vaccinemakers, but it’s also the reason so few people are able to control an HIV infection naturally, like the six people studied in Nussenzweig’s lab.

Now, understanding this process could be key to the next vaccines . . . [Nussenzweig says], “The antibody is always chasing the virus around. You get an antibody. It has an effect. Then the virus mutates away from it.” The body then creates new versions of the antibodies to tackle the new mutated virus — but the virus is already mutating again. “The antibodies can never catch up,” he says.