Signals through membrane Ig of peritoneal CD5 B cells to suppress LPS-induced Ig secretion.
Murine peritoneal CD5 B cells include many B cells reactive with bromelain-treated mouse RBC (BrMRBC). Anti-BrMRBC B cells are through to expand after selection by self-antigens, but little is known about signals through their membrane Ig (mIg). Most anti-BrMRBC antibodies use VH11 and V kappa 9 genes, and VH11/V kappa 9-type antibodies are detectable specifically with rabbit anti-idiotype antibodies (here referred to as RAIa). Preincubation of peritoneal cells with RAIa at 37 degrees C before LPS stimulation reduced LPS-induced secretion of RAIa-detectable Ig. To render RAIa-reactive B cells hyporesponsive, a continuous reaction of their mIg with RAIa was necessary. Binding of BrMRBC to RAIa-reactive B cells hardly affected their LPS reactivity. It appears that fresh mIg deliver the suppressive signals after reacted with RAIa, and the degree of hyporesponsiveness of a RAIa-reactive B cell depends on the amount of mIg-RAIa complexes. RAIa-suppressed B cells could regenerate mIg in the absence of RAIa and could respond to LPS to enlarge. It is suggested that binding of RAIa to mIg renders RAIa-reactive B cells without proliferation in an anergy state, where synthesis of secretory Ig is rather specifically suppressed.
Kawaguchi
S
S
Department of Microbiology and Immunology, Shimane Medical University, Izumo, Japan.
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D015703:Antigens, CD / Q000276:immunology*; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D018956:CD5 Antigens; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation; D051379:Mice; D008809:Mice, Inbred C3H; D008808:Mice, Inbred CBA; D010529:Peritoneal Cavity / Q000166:cytology; D011947:Receptors, Antigen, B-Cell / Q000276:immunology*
D000888:Antibodies, Anti-Idiotypic; D015703:Antigens, CD; D018956:CD5 Antigens; D008070:Lipopolysaccharides; D011947:Receptors, Antigen, B-Cell