HIV vaccine research generates key antibodies in animal models

A trio of studies have all demonstrated techniques for stimulating animal cells to produce antibodies that either could stop HIV from infecting human cells in the laboratory or had the potential to evolve into such antibodies.

In one study, published in Science, researchers demonstrate that a laboratory-designed molecular complex can stimulate rabbits and monkeys to produce powerful neutralising antibodies against a tough-to-neutralise HIV strain. The complex is similar to the part of HIV that binds to cells—a structure that has been difficult to copy as the kind of stand-alone molecule that an HIV vaccine potentially would need.

In another study, published in Cell, scientists took the first step toward confirming the prevailing hypothesis of how an HIV vaccine will need to be designed to elicit antibodies that stop a wide range of HIV strains from infecting human cells. The researchers demonstrated in genetically modified mice that an HIV vaccine regimen likely would need to expose the immune system to one type of protein to elicit a nascent antibody with the potential to be broadly neutralizing, and then present another type of protein later on to coax a more mature form of the antibody toward final development.

The studies could lead to the development of HIV vaccines that neutralise antibodies

In the third study, published in Science, researchers used an engineered protein to stimulate B cells in genetically modified mice to produce antibodies that are precursors of the NIAID-discovered VRC01 antibody, which can neutralise a wide range of HIV strains. This study provides strong evidence that the engineered protein can kick off the production of VRC01-class broadly neutralising antibodies in the scientists’ mouse model by targeting VRC01-class progenitor cells and has potential to do the same in humans.

Together, the three papers represent an important starting point for developing HIV vaccines that can elicit broadly neutralising antibodies in people.