title: Immunity to experimental Salmonella typhimurium infections in rats. Transfer of immunity with primed CD45RC+ and CD45RC- CD4 T-cell subpopulations.
abstract: The protective effect of primed CD4 T cells against a lethal dose of Salmonella typhimurium was studied in Lewis rats. Primed CD4 T cells were obtained by inoculating Lewis rats with a non-lethal dose of S. typhimurium. Four weeks after the infection, spleen CD4 T cells were separated by antibody-coated magnetic microspheres using an antibody against the CD4 molecule (W3/25). The cells were separated according to their expression of the CD45RC isoform of the leukocyte common antigen by FACS. CD45RC+ and CD45RC- CD4 T-cell subpopulations were transferred to untreated rats 24 h prior to infection with S. typhimurium. Transfer of CD45RC+ and CD45RC- CD4 T cells induced a significant survival, p = 0.022 and p = 0.023 respectively, following inoculation with S. typhimurium compared to animals with no cells transferred. The infection induced an increase in CD4 T cells expressing the CD45RC isoform compared to untreated controls (p < 0.001). It is concluded that both CD45RC+ and CD45RC- cells can induce a significant protection against S. typhimurium infections in rats. Therefore the CD45RC antigen cannot be used as a phenotypic marker for functionally distinct CD4 T-cell subpopulations. The infection-induced increase in CD45RC+ cells is most likely due to generation of antigen-specific memory T cells.
authors.affiliation: Department of Biological Sciences, Royal Danish School of Pharmacy, University of Copenhagen, Denmark.
authors.forename: P
authors.initials: P
authors.lastname: Thygesen
authors.forename: H B
authors.initials: HB
authors.lastname: Christensen
authors.forename: H P
authors.initials: HP
authors.lastname: Hougen
authors.forename: J
authors.initials: J
authors.lastname: Rygaard
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D007111:Immunity, Cellular; D016130:Immunophenotyping; D017493:Leukocyte Common Antigens / Q000096:biosynthesis / Q000276:immunology*; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D012481:Salmonella Infections, Animal / Q000276:immunology*; D012486:Salmonella typhimurium / Q000276:immunology*; D016019:Survival Analysis; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D017493:Leukocyte Common Antigens