Envelope clue to general HIV vaccine

The ideal HIV vaccine would elicit humoral responses effective against a broad spectrum of primary HIV strains but immunogens capable of generating such antibodies in humans have been difficult to identify. In the early edition of Proceedings of the National Academy of Sciences, Timothy Fouts and colleagues at the University of Maryland Biotechnology Institute, Baltimore, US, show that crosslinked HIV-1 envelope–CD4 receptor complexes could elicit broadly cross-reactive neutralizing antibodies in rhesus macaques (Proc Natl Acad Sci USA 2002, DOI/10.1073/pnas.182412199).

Fouts et al. analyzed the immunologic potential of a HIV-1IIIB envelope structure expressed as either a gp120–CD4 or a gp140–CD4 complex. They observed that in rhesus macaques, crosslinked complexes of soluble human CD4 and gp120 or gp140 envelope glycoproteins generated antibodies that neutralized a wide range of primary HIV-1 isolates. These effects were regardless of coreceptor usage, genetic subtype or geographic origin of the virus.

"Overall, our findings suggest that gp120–CD4 ...