title: Effect of age on susceptibility to Salmonella Typhimurium infection in C57BL/6 mice.
abstract: Ageing is associated with a decline in immune function, which predisposes the elderly to a higher incidence of infections. Information on the mechanism of the age-related increase in susceptibility to Salmonella enterica serovar Typhimurium (S. Typhimurium) is limited. In particular, little is known regarding the involvement of the immune response in this age-related change. We employed streptomycin (Sm)-pretreated C57BL/6 mice to develop a mouse model that would demonstrate age-related differences in susceptibility and immune response to S. Typhimurium. In this model, old mice inoculated orally with doses of 3 x 10(8) or 1 x 10(6) c.f.u. S. Typhimurium had significantly greater S. Typhimurium colonization in the ileum, colon, Peyer's patches, spleen and liver than young mice. Old mice had significantly higher weight loss than young mice on days 1 and 2 post-infection. In response to S. Typhimurium infection, old mice failed to increase ex vivo production of IFN-gamma and TNF-alpha in the spleen and mesenteric lymph node cells to the same degree as observed in young mice; this was associated with their inability to maintain the presence of neutrophils and macrophages at a 'youthful' level. These results indicate that Sm-pretreated C57BL/6 old mice are more susceptible to S. Typhimurium infection than young mice, which might be due to impaired IFN-gamma and TNF-alpha production as well as a corresponding change in the number of neutrophils and macrophages in response to S. Typhimurium infection compared to young mice.
authors.affiliation: Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Ren
authors.affiliation: Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA.
authors.forename: Raina
authors.initials: R
authors.lastname: Gay
authors.affiliation: Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA.
authors.forename: Adam
authors.initials: A
authors.lastname: Thomas
authors.affiliation: Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA.
authors.forename: Munkyong
authors.initials: M
authors.lastname: Pae
authors.affiliation: Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA.
authors.forename: Dayong
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Microbiology and Molecular Biology, Tufts University, 136 Harrison Avenue, Boston, MA 02111, USA.
authors.forename: Lauren
authors.initials: L
authors.lastname: Logsdon
authors.affiliation: Department of Microbiology and Molecular Biology, Tufts University, 136 Harrison Avenue, Boston, MA 02111, USA.
authors.forename: Joan
authors.initials: J
authors.lastname: Mecsas
authors.affiliation: Nutritional Immunology Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA.
authors.forename: Simin Nikbin
authors.initials: SN
authors.lastname: Meydani
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D016207:Cytokines / Q000378:metabolism; D004198:Disease Susceptibility; D005243:Feces / Q000737:chemistry; D007781:Lactoferrin / Q000032:analysis; D008198:Lymph Nodes / Q000166:cytology; D051379:Mice; D008810:Mice, Inbred C57BL; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000472:pathogenicity*; D013154:Spleen / Q000166:cytology
chemical_list: D016207:Cytokines; D007781:Lactoferrin