Maturation of envelope-specific antibody responses to linear determinants in monkeys inoculated with attenuated SIV

We have previously used a panel of quantitative and qualitative serological assays to define a lengthy and complex maturation of envelope-specific ant ibody responses in monkeys experimentally infected with attenuated simian i mmunodeficiency virus (SIV) that is closely associated with the temporal de velopment of enduring and protective immunity to experimental virus challen ge. To elucidate in more detail the changes in antibody specificity associa ted with this maturation, we describe here 'domain-specific' serological st udies to characterize the evolution of antibody responses to defined linear determinants of the SIV envelope protein. The results of these studies rev eal for the first time distinguishing differences in the evolution of antib ody populations to distinct envelope peptide segments, as determined by mea surements of antibody titer and avidity, indicating different patterns of a ntibody maturation to distinct linear envelope antigenic determinants. Thus , these data demonstrate the potential for domain-specific serology to prod uce a high-resolution characterization of SIV-specific antibody responses t hat can be used to evaluate experimental vaccine responses and to identify potential immune correlates of protection.