The key to bringing down HIV is to find its weak spots, those parts in its viral armor that allow doctors to disrupt HIV’s aggressive and relentless infection of healthy immune cells.

In a study published in Science, researchers led by the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases report on the newest such vulnerability. The team studied the blood of a unique HIV positive person who happened to make antibodies against parts of HIV that aren’t normally targeted, and discovered this special antibody stuck to a part of the virus that it uses to bind to healthy cells. By attaching to the virus at that point, it prevents HIV from properly fusing with the cell and infecting it.

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The scientists are particularly encouraged by the potential of this antibody since it targets a site on the virus that’s relatively easy to exploit.

“The region of the virus that is recognized by the antibody is what’s different here,” says Peter Kwong, chief of structural biology at the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases and one of the authors of the paper.

Knowing of this weakness of HIV could help vaccine developers to find ways to educate the immune system to target this spot, and build up protection against infection. The idea is to immunize people to generate these powerful antibodies against HIV before they get infected, so they can overwhelm the virus and thwart its attempts at infecting healthy cells.

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