Induction of HIV-1 subtype B and AE-specific neutralizing antibodies in mice and macaques with DNA prime and recombinant gp140 protein boost regimens

We developed highly expressing clade B and AE DNA and envelope protein (Env) vaccines for evaluation in mice and macaques as DNA prime/protein boost regimens. High levels of Env-specific antibodies were induced in mice, albeit with limited neutralizing activity in vitro. A combined clade B and AE regimen induced high titer Env-specific antibody in two pigtail macaques that neutralized several strains of HIV-1. However, upon mucosal challenge with SHIVSF162P3 no protection from infection was observed. Although the vaccines tested provide a platform for inducing robust humoral immunity, further refinements to broaden coverage against divergent strains and induce mucosal immunity are needed.