B cell immunofocusing and repriming in two HIV-1 Env immunization regimens.

Diverse and rapidly mutating viruses pose challenges to immunogen and vaccine design. In this study, we evaluated the ability of memory B-cells obtained from two independent NHP trials to cross-react with individual HIV-1 vaccine components of two different multivalent immunization strategies. We demonstrated that while an HIV-1 Env multiclade, multivalent immunization regimen resulted in a dominant memory B-cell response that converged toward shared epitopes, in a sequential immunization with clonally-related non-stabilized gp140 HIV-1 Envs followed by SOSIP-stabilized gp140 trimers, the change in immunogen format resulted in repriming of the B-cell response.