title: Transfer of primed CD4+OX40- T lymphocytes induces increased immunity to experimental Salmonella typhimurium infections in rats.
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 non-adherent mononuclear cells were isolated. The cells were separated according to their expression of CD4 and the OX40 antigen by FACS. OX40+ and OX40- CD4+ T-cell subpopulations were together with unsorted CD4+ T cells transferred to untreated rats 24 h prior to infection with S. typhimurium. Transfer of either unsorted CD4+ T cells or CD4+ T cells sorted into OX40- or OX40- subpopulations significantly increased animal survival compared to controls. Animals receiving OX40+CD4+ T cells did not differ significantly in survival probability from those receiving unsorted CD+ T cells. However, animals receiving OX40-CD4+ T cells had a significantly better survival compared to animals given unsorted CD4+ T cells. It is concluded that OX40-CD4+ T cells can induce significant protection against S. typhimurium infections in rats. This is most likely due to the fact that the OX40-CD4+ T-cell population contains a significant number of antigen-specific memory T cells that have returned to a resting state.
authors.affiliation: Department of Biological Sciences, Royal Danish School of Pharmacy, 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 / Q000166:cytology / Q000276:immunology / Q000637:transplantation*; D017690:Cell Transplantation; D007109:Immunity; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D053262:Receptors, OX40; D018124:Receptors, Tumor Necrosis Factor; D012481:Salmonella Infections, Animal / Q000276:immunology* / Q000517:prevention & control; D012486:Salmonella typhimurium / Q000276:immunology*; D013154:Spleen / Q000166:cytology; D016176:T-Lymphocyte Subsets / Q000276:immunology; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000276:immunology*
chemical_list: D053262:Receptors, OX40; D018124:Receptors, Tumor Necrosis Factor; C505718:Tnfrsf4 protein, rat; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7