The epigenetic and transcriptional events controlling the differentiation of antibody- secreting plasma cells (PCs) from activated B cells remain unclear. Furthermore, though memory B cells and naive B cells in the marginal zone (MZ) of the spleen are known to generate PCs faster than the bulk of naive B cells, how PC inductive signals integrate with other processes such as cell division to drive PC differentiation in distinc B cell subsets is unknown. The main goals of this R21 application are to understand how epigenetic modifiers control the kinetics of early PC differentiation for MZ and memory B cells and the role of cell division in these processes with an emphasis on the regulated expression of the PC-required transcription factor Blimp1. To this end we will: 1) Define the role of cell divisin in PC differentiation, and 2) Define the epigenetic regulation of the Blimp1 locus upon B cell activation and selection. These studies will enhance knowledge of the processes underlying the generation of all PCs including pathogenic PCs secreting self-reactive antibodies.
The factors underlying the initial generation of antibody secreting plasma cells are not understood. These studies will define the relationship between cell division and the expression of transcription factors needed for B cells to become plasma cells. The results will have direct implications for therapeutic strategies to combat antibody- mediated autoimmune diseases or conversely to induce long-lived immunity.
