New research led by scientists has represented a leap forward in the effort to find a vaccine against HIV virus.

Scientists at The Scripps Research Institute (TSRI), International AIDS Vaccine Initiative (IAVI) and The Rockefeller University showed in mice that an experimental vaccine candidate designed at TSRI can stimulate the immune system activity necessary to stop HIV infection.

The researchers' long-term goal is to design a vaccine that prompts the body to produce antibodies that bind to HIV and prevent infection. While many vaccines for other diseases use a dead or inactive version of the disease-causing microbe itself to trigger antibody production, immunizations with "native" HIV proteins are ineffective in triggering an effective immune response, due to HIV's ability to evade detection from the immune system and mutate rapidly into new strains.

This challenge has led many researchers to believe that a successful AIDS vaccine will need to consist of a series of related, but slightly different proteins (immunogens) to train the body to produce broadly neutralising antibodies against HIV--a twist on the traditional "booster" shot, where a person is exposed to the same immunogen multiple times.

In the new studies, the scientists tested one of these potential proteins, an immunogen called eOD-GT8 60mer, a protein nanoparticle designed to bind and activate B cells needed to fight HIV. The eOD-GT8 60mer was developed in the Schief lab and tested in mouse models engineered by the Nemazee lab to produce antibodies that resemble human antibodies.

Using a technique called B cell sorting, the researchers showed that immunizations with eOD-GT8 60mer produced antibody "precursors," with some of the traits necessary to recognize and block HIV infection. This suggested that eOD-GT8 60mer could be a good candidate to serve as the first in a series of immunizations against HIV.

The research is published in the journals Cell and Science.