Antigen presentation by dendritic cells for B cell activation

•B cells preferentially respond to membrane-associated antigens.•Two main cell types, macrophages and follicular dendritic cells, implicated in presentation of native antigen to B cells.•Conventional dendritic cells (cDC) are essential for T cell activation and may also present native antigen to B cells.•Type 2 cDC have been strongly implicated in antigen presentation to B cells, but Type 1 cDC may also participate.•A cDC subsets’ role in B cell immunity may be dictated by the location, pathogen type and receptors used to capture antigen. B cells are efficiently activated by antigens presented on cell membranes, which provide opportunity for receptor cross-linking and antigen capture. The two main cell types implicated in native antigen presentation to B cells are follicular dendritic cells (FDC), which reside in B cell follicles, and CD169+ macrophages, which line the antigen-exposed surfaces of these follicles in both the lymph nodes and the spleen. There is mounting evidence, however, that conventional dendritic cells (cDC) can also participate in native antigen presentation to B cells. This underappreciated role, largely hidden by the simultaneous need for cDC to participate in T cells priming, appears to be primarily mediated by the type 2 subset of cDC (cDC2), but may also be a function of cDC1. Better understanding of how cDC participate in B cell priming is likely to improve our capacity to develop effective humoral vaccines.