A trimeric protein boost to follow MVA vaccination for clade C HIV-1

A trimeric, cyclically permuted protein vaccine based on HIV gp120 could improve protection against infection with clade C HIV-1 viruses following vaccination with a live attenuated modified vaccinia Ankara (MVA) vaccine expressing HIV envelope proteins that form virus-like particles. Engineering of three trimeric, cyclically permuted gp120 variants followed by biolayer interferometry-based screening for binding by envelope-specific broadly neutralizing antibodies identified a clade C–based protein that presented a native-like quaternary epitope.

In rhesus macaques, priming with the MVA vaccine followed by boosting with the trimeric protein plus an Escherichia coli enterotoxin adjuvant via either an oral or parenteral route induced production of antibodies with broad polyfunctional profiles and proliferation of T cells expressing low levels of the HIV target protein CCR5...