My research is focused on the development and evaluation of Env based immunogens designated as SOSIP trimers. These are the new generation immunogens that mimic the native Env trimer structure and can be expressed as extracellular recombinant proteins. The immunogenicity studies showed that these immunogens do elicit the neutralizing antibodies (NAbs) against the autologous tier-2 virus. The current focus is on the understanding of the targets of these vaccine elicited NAbs and how to broaden this response to heterologous tier-2 viruses.