title: Divergence of protection induced by bacterial products and sepsis-induced immune suppression.
abstract: Susceptibility to bacterial infections after a primary immune stimulation differs drastically depending on the presensitization of the innate immune system. To determine the conditions that either induce protection or enhanced susceptibility to infection with Salmonella enterica serovar Typhimurium, we pretreated mice either with tumor necrosis factor (TNF), whole killed bacteria, or sublethal cecal ligation and puncture (CLP) as a mouse model for septic peritonitis. Impaired production of the cytokines TNF, interleukin-6 (IL-6), and IL-10 was induced by these pretreatment schedules, with TNF-signaling not being essential for this effect. Injection of TNF or killed bacteria enhanced survival of mice infected subsequently with serovar Typhimurium. In contrast, sepsis such as that induced by CLP only protected from shock induced by d-galactosamine and lipopolysaccharide or by a high dose of bacteria but sensitized to a secondary bacterial infection. Such sepsis-induced enhanced susceptibility to infection was critically dependent on TNF function.
authors.affiliation: Institute of Immunology, University of Regensburg, F.-J.-Strauss-Allee, D-93042 Regensburg, Germany.
authors.forename: Theo
authors.initials: T
authors.lastname: Sterns
authors.forename: Nils
authors.initials: N
authors.lastname: Pollak
authors.forename: Bernd
authors.initials: B
authors.lastname: Echtenacher
authors.forename: Daniela N
authors.initials: DN
authors.lastname: Männel
mesh_terms: D000818:Animals; D016207:Cytokines / Q000378:metabolism; D007108:Immune Tolerance / Q000187:drug effects / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D012481:Salmonella Infections, Animal / Q000276:immunology* / Q000401:mortality; D012486:Salmonella typhimurium / Q000276:immunology*; D018805:Sepsis / Q000276:immunology*; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D016207:Cytokines; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha