title: Differences in the immune responses of mice and sheep to an aromatic-dependent mutant of Salmonella typhimurium.
abstract: A live mutant aroA Salmonella serotype Typhimurium ovine strain (S25/1) could be cultured from tissues of mice for up to 90 days after oral infection. Following vaccination, high levels of Salmonella-specific serum IgM, IgG and IgA were produced in addition to high levels of specific intestinal IgA. Moreover, there was also evidence of Salmonella-specific cell-mediated immunity in vaccinated mice in the form of strong delayed-type hypersensitivity and the production of interferon-gamma (IFN-tau) by spleen cells stimulated with Salmonella antigen. The aroA strain was also recovered from the mesenteric lymph nodes and most tissues examined from sheep vaccinated by the oral route. Salmonella-specific IgM was detected in the serum; however, specific IgG responses were very low and there was an absence of specific copro-antibody. Although strong Salmonella-specific lymphocyte proliferative responses were detected, they did not result in the production of IFN-tau and flow cytometric analysis revealed that the proliferating cells were predominantly B lymphocytes. Despite the absence of strong vaccine-specific immune responses in vaccinated sheep compared with those seen in mice, both mice and sheep were protected against challenge with virulent wild-type strain S25/1.
authors.affiliation: Moredun Research Institute, Edinburgh.
authors.forename: F R
authors.initials: FR
authors.lastname: Brennan
authors.forename: J J
authors.initials: JJ
authors.lastname: Oliver
authors.forename: G D
authors.initials: GD
authors.lastname: Baird
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D019883:Alkyl and Aryl Transferases; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis* / Q000097:blood; D001402:B-Lymphocytes / Q000276:immunology; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005798:Genes, Bacterial; D006968:Hypersensitivity, Delayed; D007071:Immunoglobulin A, Secretory / Q000096:biosynthesis; D007136:Immunoglobulins / Q000097:blood; D007370:Interferon Type I; D007371:Interferon-gamma / Q000096:biosynthesis; D007413:Intestinal Mucosa / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D016254:Mutagenesis, Insertional; D011257:Pregnancy Proteins; D012481:Salmonella Infections, Animal / Q000517:prevention & control; D012486:Salmonella typhimurium / Q000201:enzymology / Q000235:genetics / Q000276:immunology*; D012756:Sheep; D013154:Spleen / Q000166:cytology / Q000276:immunology; D014166:Transferases / Q000235:genetics* / Q000276:immunology; D014611:Vaccination; D014614:Vaccines, Synthetic / Q000235:genetics / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D007071:Immunoglobulin A, Secretory; D007136:Immunoglobulins; D007370:Interferon Type I; D011257:Pregnancy Proteins; D014614:Vaccines, Synthetic; C020947:interferon tau; D007371:Interferon-gamma; D014166:Transferases; D019883:Alkyl and Aryl Transferases; D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase