In vivo effects of lipopolysaccharide on lymphoid and non-lymphoid cells in the mouse spleen. Suppressive and adjuvant effects of LPS on the development of specific antibody forming cells in situ.
Mice were immunized i.v. with 2,4,6-trinitrophenyl (TNP)-carrier conjugates and received lipopolysaccharide (LPS) before, simultaneously with or after these antigens, in order to study the effects of LPS on the in situ development of anti-TNP antibody forming cells in the spleen. LPS given before, simultaneously with or shortly after the thymus dependent (TD) antigen TNP-keyhole limpet haemocyanin (KLH) suppressed the development of anti-TNP antibody forming cells in the spleen, but serum IgM-anti-TNP titres were not reduced, suggesting a selective inhibiting effect of LPS on the local immune response in the spleen. Splenic responses to thymus independent (TI) antigens TNP-Ficoll and TNP-LPS were not reduced when these antigens were administered one day after LPS. LPS given 4 days after TNP-KLH and 1 day before killing of the animals had induced severe alterations in splenic histology, but we found no marked influence on numbers and distribution pattern of anti-TNP forming cells. Results indicate that the LPS induced suppression of the immune response to TD antigens in the spleen is not caused by a direct effect of LPS on antigen reactive B-lymphocytes or on the anti-TNP antibody forming cells themselves. Possible explanations for the LPS-induced immunosuppression are discussed.
D000276:Adjuvants, Immunologic; D000818:Animals; D000921:Antibody-Producing Cells / Q000187:drug effects*; D000941:Antigens / Q000276:immunology; D000955:Antigens, T-Independent / Q000276:immunology; D005362:Ficoll; D006433:Hemocyanins; D007136:Immunoglobulins / Q000378:metabolism; D007166:Immunosuppressive Agents; D008070:Lipopolysaccharides / Q000494:pharmacology*; D051379:Mice; D013154:Spleen / Q000276:immunology*; D014301:Trinitrobenzenes / Q000276:immunology
D000276:Adjuvants, Immunologic; D000941:Antigens; D000955:Antigens, T-Independent; D007136:Immunoglobulins; D007166:Immunosuppressive Agents; D008070:Lipopolysaccharides; D014301:Trinitrobenzenes; D005362:Ficoll; D006433:Hemocyanins; C032808:keyhole-limpet hemocyanin