title: Polyclonal activation of human peripheral blood B lymphocytes by formaldehyde-fixed Salmonella paratyphi B. I. Immunoglobulin production without DNA synthesis.
abstract: A "new" polyclonal activator of human peripheral blood B cells, formaldehyde-fixed Salmonella paratyphi B, is described. This bacterium does not stimulate cell proliferation as measured by incorporation of tritiated thymidine but does stimulate a subpopulation of B cells to secrete large amounts of IgM, IgG, and IgA in 7-day cell cultures. The immunoglobulins (Ig) produced by cells responding to S. paratyphi B are not specific antibodies against the bacterial antigens. In comparison with other B cell activators (pokeweed mitogen, Staphylococcus aureus Cowan I, and lipopolysaccharide), S. paratyphi B stimulation produced greater amounts of IgM but less IgG than pokeweed mitogen (PWM) or S. aureus Cowan I; lipopolysaccharide failed to stimulate significant Ig production on day 7 in most cases. In addition, the response to S. paratyphi apparently did not require T cell collaboration. These results suggest that the B cell subpopulation(s) responding to S. paratyphi B may be more differentiated B cells than those responding to either PWM or S. aureus Cowan I. Peripheral blood mononuclear cells from five patients with common variable immunodeficiency without evidence of abnormal suppressor T cells or monocytes failed to respond to S. paratyphi B, whereas cells from two of the same patients responded well to S. aureus Cowan I and partially to PWM. Thus, S. paratyphi B appears to be superior to other B cell activators for studies of B cell function in normal and abnormal states.
mesh_terms: D001402:B-Lymphocytes / Q000276:immunology*; D002999:Clone Cells / Q000276:immunology; D004247:DNA / Q000096:biosynthesis*; D004306:Dose-Response Relationship, Immunologic; D005557:Formaldehyde / Q000494:pharmacology; D006801:Humans; D007070:Immunoglobulin A / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D007136:Immunoglobulins / Q000096:biosynthesis*; D007153:Immunologic Deficiency Syndromes / Q000276:immunology; D008213:Lymphocyte Activation; D008934:Mitogens / Q000494:pharmacology; D011043:Pokeweed Mitogens / Q000494:pharmacology; D012484:Salmonella paratyphi B / Q000276:immunology
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins; D008934:Mitogens; D011043:Pokeweed Mitogens; D005557:Formaldehyde; D004247:DNA