Terminal maturation of resting B cells by proliferation-independent B cells differentiation factors.
Using response to four different BCDF preparations as a model of B cell maturation, we have shown that induction of B cell proliferation abrogates terminal maturation of these cells. In fact, response to some BCDFs can occur in the presence of inhibitors of DNA replication, suggesting that there are proliferation-independent as well as proliferation-dependent BCDFs. These findings cannot be explained by changes in the kinetics of the BCDF response, nor can they be reversed by repletion of media or changing cell densities. Proliferation-independent BCDFs appear to exert their effects on dense, resting 4F2- B cells rather than more activated B cells. This is in contrast to B cell differentiation signals of IL-2 alone or SAC and IL-2 in concert. These data suggest that the current models of B cell activation and maturation may require some reorganization, relegating the proliferative phase of B cell maturation to a lesser role. In addition, evidence is provided for the fact that the resting B cell may have the full complement of receptors for BCDF as well as BCGF and BCPF and may help account for the inherent nonspecificity of the immune response.
D000917:Antibody Formation; D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface / Q000494:pharmacology*; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D002454:Cell Differentiation; D006801:Humans; D007399:Interphase; D008213:Lymphocyte Activation; D008954:Models, Biological
D000944:Antigens, Differentiation, B-Lymphocyte; D000954:Antigens, Surface