title: Differential response of bovine monocyte-derived macrophages and dendritic cells to infection with Salmonella typhimurium in a low-dose model in vitro.
abstract: Exposing bovine dendritic cells (DC) and macrophages (MPhi) to Salmonella typhimurium at a ratio of 1 cell to 10 bacteria had a cytotoxic effect that was not evident with a ratio of 1000 cells to 1 bacterium. This lower dose was considered to mimic more closely the in vivo situation and a comparison was made with this model of the consequences of infection for MPhi and DC. DC infected with S. typhimurium up-regulated cell surface expression of major histocompatibility class I (MHC-I), MHC-II, CD40, CD80 and CD86. In contrast, infected MPhi did not exhibit detectable changes in expression of cell surface molecules, except for a marginal increase in CD40. mRNA transcription for tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6 and inducible nitric oxide synthase was up-regulated in both infected DC and infected MPhi, although mRNA transcription for granulocyte-macrophage colony-stimulating factor and IL-12p40 was up-regulated only in infected DC and for IL-10 was only in infected MPhi. Infected DC had an increased ability to stimulate both allogeneic and antigen-specific T-cell responses compared to non-infected controls. In contrast, infected MPhi showed an increased ability to induce allogeneic responses but this was less than seen for DC and no enhancement of ability to induce antigen-specific T cell responses was seen. Thus, in a low-dose infection model that does not result in the cytotoxicity of a substantial percentage of antigen presenting cells, bovine MPhi and DC respond differently to infection with S. typhimurium and this could have important implications for the development of the immune response.
authors.affiliation: Institute for Animal Health, Compton, Newbury, UK. mari.norimatsu@bbsrc.ac.uk
authors.forename: Mari
authors.initials: M
authors.lastname: Norimatsu
authors.forename: James
authors.initials: J
authors.lastname: Harris
authors.forename: Victoria
authors.initials: V
authors.lastname: Chance
authors.forename: Gordon
authors.initials: G
authors.lastname: Dougan
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Howard
authors.forename: Bernardo
authors.initials: B
authors.lastname: Villarreal-Ramos
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology* / Q000382:microbiology; D000954:Antigens, Surface / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology*; D018929:Cell Culture Techniques / Q000379:methods; D002470:Cell Survival; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics; D003713:Dendritic Cells / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D008213:Lymphocyte Activation / Q000276:immunology; D008264:Macrophages / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D018613:Microscopy, Confocal; D009000:Monocytes / Q000276:immunology; D012481:Salmonella Infections, Animal / Q000276:immunology*; D012486:Salmonella typhimurium; D014158:Transcription, Genetic
chemical_list: D000954:Antigens, Surface; D016207:Cytokines