Hyperglycosylated gp120 mutants may induce broad humoral responses.

2003 JUN 11 - (NewsRx.com & NewsRx.net) -- by Michael Greer, senior medical writer - Polymorphic forms of the HIV coat protein gp120 may elicit broad humoral responses, researchers in the United States say.

"The ability to induce broadly neutralizing antibodies should be a key component of any forthcoming vaccine" against HIV, noted Ralph Pantophlet and colleagues at the Scripps Research Institute in La Jolla, California. However, "one potential vaccine candidate, monomeric gp120, has generally failed to elicit such antibodies."

A hyperglycosylated gp120 mutant preferentially bound to a broadly neutralizing antibody, and could form the basis for a more effective vaccine, Pantophlet and coauthors reported.

The researchers had previously found that alanine substitutions around gp120's "Phe-43 cavity" improved binding of the broadly neutralizing antibody b12. These mutations also inhibited binding of weakly neutralizing CD4-binding site antibodies, according to the report.

Seeking to build on these results, the scientists added a series of N-glycosylation motifs to key positions in the gp120 genome. A gp120 mutant with these extra motifs and the previously described alanine substitutions maintained b12 binding, but was unable to bind antibodies with little or no neutralizing ...