Antigen-specific B cell detection reagents: use and quality control.

Tests for immunoglobulin reactivity with specific antigens are some of the oldest and most used assays in immunology. With efforts to understand B cell development, B cell dysregulation in autoimmunity, and to generate B cell vaccines for infectious agents, investigators have found the need to understand the ontogeny and regulation of epitope-specific B cell responses. The synchrony between surface and secreted antibodies for individual B cells has led to the development of reagents and techniques to identify antigen-specific B cells via reagent interactions with the B cell receptor complex. B cell antigen-specific reagents have been reported for model systems of haptens, for whole proteins, and for identification of double stranded (ds) DNA antibody-producing B cells using peptide mimics. Here we provide an overview of reported techniques for the detection of antigen-specific B cell responses via secreted antibody or by the surface B cell receptor and briefly discuss our recent work developing a panel of reagents to probe the B cell response to HIV-1 envelope. We also present an analysis of strengths and weaknesses of various methods for flow cytometric analysis of antigen-specific B cells.