title: Resolution of chlamydial genital infection in B-cell-deficient mice and immunity to reinfection.
abstract: The purpose of this investigation was to determine the relative roles of the humoral and cell-mediated immune responses in the resolution of chlamydial genital infection of mice and resistance to reinfection. To this end, female BALB/c mice were rendered B cell deficient by treatment with heterologous anti-immunoglobulin M (IgM) serum from birth. Controls were similarly treated with either normal serum or phosphate-buffered saline. Before inclusion in each experiment, anti-IgM-treated mice were screened for the absence of IgM in serum and for the presence of cell-mediated immune responses. In addition, spleen cells from anti-IgM-treated mice responded to concanavalin A and phytohemagglutinin but not to lipopolysaccharide. By these criteria, mice were designated B cell deficient. B-cell-deficient mice and controls were inoculated intravaginally with a suspension of mouse pneumonitis agent (MoPn), a Chlamydia trachomatis biovar. All B-cell-deficient mice resolved the infection. Additionally, no significant difference was seen in the course of the infection in B-cell-deficient mice when compared with controls. In contrast to control mice, B-cell-deficient mice displayed no detectable antibody responses to MoPn in serum or in genital secretions. However, both B-cell-deficient mice and controls developed delayed-type hypersensitivity and T-cell proliferative responses to MoPn. When challenged 53 days after primary infection, no significant difference was seen in the resistance of B-cell-deficient mice to reinfection when compared with that of the controls. These data indicate that cell-mediated immune mechanisms play an important role in the resolution of and resistance to chlamydial genital infection in this model.
authors.affiliation: Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock 72205.
authors.forename: K H
authors.initials: KH
authors.lastname: Ramsey
authors.forename: L S
authors.initials: LS
authors.lastname: Soderberg
authors.forename: R G
authors.initials: RG
authors.lastname: Rank
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001402:B-Lymphocytes / Q000276:immunology*; D002690:Chlamydia Infections / Q000276:immunology*; D003877:Dermatitis, Contact / Q000276:immunology; D005260:Female; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007111:Immunity, Cellular; D008213:Lymphocyte Activation; D051379:Mice; D010081:Oxazolone; D013154:Spleen / Q000276:immunology; D014627:Vaginitis / Q000276:immunology / Q000382:microbiology*
chemical_list: D000907:Antibodies, Bacterial; D010081:Oxazolone