Immunity conferred upon mice by anti-LPS monoclonal antibodies in murine brucellosis.
An immune serum infused into mice prior to intravenous virulent Brucella abortus challenge may reduce initial colonization of the spleen on day 7 post-challenge and increase bacteriolysis in the spleen and liver, as evidenced on day 21. Three monoclonal antibodies (IgG1, IgG3 and IgG2a) directed toward the lipopolysaccharide-A epitope (LPS-A) of B. abortus were studied in this model and compared with three previously studied polyclonal immune sera. The three monoclonals restricted spleen infection on day 7 post-challenge and spleen and liver infections on day 21. These early and late effects were similar to those obtained with the two polyclonal sera of high anti-LPS-A titres, namely, serum from mice either infected by B. abortus or vaccinated with a cell-wall B. abortus fraction. In contrast, serum from mice vaccinated with LPS-M from B. melitensis, which had a high anti-LPS-M but a low anti-LPS-A titre, had lower activity, evidenced at day 7 only. Hence, immune serum protection was mediated by antibodies directed toward the LPS-dominant epitope of the challenge strain.
D000818:Animals; D000907:Antibodies, Bacterial / Q000008:administration & dosage*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D002003:Brucella abortus / Q000276:immunology; D002006:Brucellosis / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D005260:Female; D008070:Lipopolysaccharides / Q000276:immunology*; D008099:Liver / Q000382:microbiology; D051379:Mice; D013154:Spleen / Q000382:microbiology
D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D008070:Lipopolysaccharides