Antibody web croppedIllustration by Christina Corbaci at Scripps Research; provided courtesy of Ann Hessell at Scripps Research.

IAVI launched the Neutralizing Antibody Center (NAC) in 2002 to study broadly neutralizing antibodies (bNAbs) and to use this information to design HIV vaccine candidates. In 2006, IAVI and the NAC launched Protocol G – a project of unprecedented scale and ambition – to hunt for highly potent, broad-spectrum bNAbs from human samples around the world. Research partners in seven countries in Australia, sub-Saharan Africa, Thailand, the U.K., and the U.S. collaborated with IAVI. More than 1,800 healthy HIV-positive volunteers donated blood samples.

IAVI and Scripps Research scientists worked with Theraclone Sciences to isolate these human samples and with Monogram Biosciences to screen them for broadly neutralizing activity against HIV. In 2009, this screening led to the isolation of the first new bNAbs seen in a decade and the first from donors in developing countries, where the majority of new HIV infections occur.

Since then, dozens of bNAbs have been identified by these researchers and IAVI’s partners at the Dale and Betty Bumpers Vaccine Research Center (VRC) at the U.S. National Institutes of Health (NIH), Rockefeller University, as well as others. The structural and biochemical analysis of these antibodies provides valuable clues for vaccine design.

Many of the bNAbs isolated by IAVI and NAC researchers have also been distributed to dozens of external researchers to assist in their work. Their findings are indispensable to the development of the next generation of HIV vaccines.