Control of memory B cell responses by extrinsic and intrinsic mechanisms

•Secondary antibody responses by memory B cells are key to protective immunity.•The memory B cell compartment consists of distinct subpopulations.•B cell-intrinsic and -extrinsic mechanisms control recall responses.•ITT phosphorylation of surface IgG is a signal signature of memory B cells.

Following primary activation, B lymphocytes generate a long-lived memory compartment to harness the organism for future reinfections by the same pathogen species. Only recently the composition and signaling signature of the scarce memory B cell pool could be explored in more detail. This review highlights current concepts of how B cells preserve their antigen experience at the cellular and molecular level.