(454a) Multiparametric Characterization of Actively-Secreting B Cells Reveals Dissimilarities Between HIV-1 Specific Responses In Blood and GALT

Traditional strategies for producing antibody-based vaccines have failed against the human immunodeficiency virus type 1 (HIV-1), hence, more deliberate approaches at immunogen design are necessary if a protective therapy is to be developed. Some persons infected by the virus are known to develop potent neutralizing antibody responses, but how these responses develop is still poorly understood. Furthermore, the identification of effective antibodies from such individuals remains challenging. Existing analyses of B cells from infected individuals have focused largely on the dormant memory B cell population, ignoring contributions from actively-secreting B cells (ASCs). In this study, we profile the repertoire of activated B cells in multiple HIV-infected patients for surface-expressed proteins, immunoglobulin isotype, and the ability of secreted antibodies to bind HIV-1 BaL, a tier 1 HIV-1 strain. Using microengraving technology, blood and tissue samples from multiple patients were analyzed. This talk will describe a comparative analysis of the HIV-1 specific B cells present in the different compartments.