Neutralizing antibody responses in HIV-1 and nonpathogenic SIV infection

Potent neutralizing antibody responses develop against the newly transmitted virus in subtype C and A HIV-1 infection within a few months and these drive cycles of viral escape and de novo antibody production. We have found that during early infection, viral escape requires multiple pathways that include both direct and indirect mechanisms. In contrast, during SIVsmm infection of sooty mangabeys, neutralizing antibody activity against the autologous virus is significantly lower, possibly representing a previously unappreciated feature of nonpathogenic infection. It is possible that this low autologous Nab activity in the sooty mangabeys from antibody recognition of targets that are poorly exposed on the native SIVsmm envelope (Env) glycoproteins.