title: Development and regulation of chlamydia-responsive murine B lymphocytes.
abstract: We have examined characteristics of chlamydia-stimulated mouse B cells as well as cells that regulate polyclonal responses in vitro. B lymphocyte proliferation stimulated by chlamydia arises at a similar time as Escherichia coli lipopolysaccharide (LPS)-induced proliferative responses during ontogeny. In contrast, development of immunoglobulin (Ig)-secreting cells after chlamydia stimulation is delayed by several weeks relative to ontogeny of LPS-inducible plaque-forming cells (PFC). The lack of Ig secretion by immature B cells is not due to a deficiency of Lyb5+ B lymphocytes, since X-linked immunodeficient (xid) NBF1 mice that lack this B lymphocyte population respond well to chlamydia stimulation. Adherent cells are important for chlamydia-stimulated B lymphocyte differentiation, but are not as necessary for their proliferation. Neither adult adherent cells nor T cells can correct the inability of immature spleen cells to develop into Ig-secreting cells; spleen cells from 2-wk-old mice (i.e., immature B cells) will not suppress adult B lymphocyte responses to chlamydia. When B lymphocytes are separated according to their buoyant densities, chlamydia stimulates low density (activated) B cells to proliferate and differentiate better than high density (resting) cells. Proliferative responses to chlamydia arise earlier during ontogeny, do not require adherent cells, and can proceed to a relatively greater extent in resting B cell population (compared with activated B cells) than induction of Ig-secreting cells.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D002692:Chlamydia trachomatis / Q000276:immunology*; D007153:Immunologic Deficiency Syndromes / Q000235:genetics / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D051379:Mice; D008807:Mice, Inbred BALB C; D008815:Mice, Inbred Strains; D008817:Mice, Mutant Strains / Q000276:immunology; D013154:Spleen / Q000254:growth & development; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D008070:Lipopolysaccharides