title: Effect of bacterial lipopolysaccharides on anti-trinitrophenyl antibody-producing cells. Nonspecific modification of the affinity at the cellular level.
abstract: The effect of lipopolysaccharide (LPS) on anti-trinitrophenyl (TNP) direct plaque-forming cells (PFC) in the spleen of mice and the affinity of antibodies produced by these PFC were examined. Simultaneous injection of bacterial LPS and TNP-coupled sheep red blood cells(SRBC) induced an obvious increase in anti-TNP PFC numbers and heightened the antibody affinity at cellular levels. The higher the doses of LPS, the greater the effects. Concomitant injection of LPS in TNP-coupled homologous mouse red blood cells (MRBC) also elicited good anti-TNP PFC response and slightly heightened the affinity. Priming with LPS and SRBC together 7 days prior to immunization did not enhance the anti-TNP PFC response and it was difficult to alter the affinity. Preinjection with small amounts of TNP-MRBC or -rabbit red blood cells and LPS simultaneously did not induce any significant increase in anti-TNP PFC secondary response after reimmunization with TNP-SRBC, but obviously heightened the antibody affinity. Injection of LPS simultaneously with the secondary immunization was effective for both the anti-TNP PFC response and the alteration of antibody affinity. These results suggest that LPS affects the control mechanisms of anti-TNP antibody affinity via the non-thymus-derived helper cell function, and the adjuvant action and alteration of antibody affinity induced by LPS are regulated by different mechanisms.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000921:Antibody-Producing Cells / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D000939:Epitopes; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D006462:Hemolytic Plaque Technique; D008070:Lipopolysaccharides / Q000494:pharmacology*; D051379:Mice; D009578:Nitrobenzenes / Q000276:immunology*; D011817:Rabbits; D012486:Salmonella typhimurium; D012710:Serum Albumin, Bovine; D013154:Spleen / Q000276:immunology
chemical_list: D000939:Epitopes; D008070:Lipopolysaccharides; D009578:Nitrobenzenes; D012710:Serum Albumin, Bovine