title: Antigen selection based on expression levels during infection facilitates vaccine development for an intracellular pathogen.
abstract: Vaccines effective against intracellular pathogens could save the lives of millions of people every year, but vaccine development has been hampered by the slow largely empirical search for protective antigens. In vivo highly expressed antigens might represent a small attractive antigen subset that could be rapidly evaluated, but experimental evidence supporting this rationale, as well as practical strategies for its application, is largely lacking because of technical difficulties. Here, we used Salmonella strains expressing differential amounts of a fluorescent model antigen during infection to show that, in a mouse typhoid fever model, CD4 T cells preferentially recognize abundant Salmonella antigens. To identify a large number of natural Salmonella antigens with high expression levels during infection, we used a quantitative in vivo screening strategy. Immunization studies with five particularly attractive candidates revealed two highly protective antigens that might permit the development of an improved typhoid fever vaccine. In conclusion, we have established a rationale and an experimental strategy that will substantially facilitate vaccine development for Salmonella and possibly other intracellular pathogens.
authors.affiliation: Department of Molecular Biology, Max Planck Institute for Infection Biology, Schumannstrasse 21/22, D-10117 Berlin, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Rollenhagen
authors.forename: Meike
authors.initials: M
authors.lastname: Sörensen
authors.forename: Konstantin
authors.initials: K
authors.lastname: Rizos
authors.forename: Robert
authors.initials: R
authors.lastname: Hurvitz
authors.forename: Dirk
authors.initials: D
authors.lastname: Bumann
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics*; D001428:Bacterial Vaccines / Q000235:genetics / Q000276:immunology*; D001483:Base Sequence; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D015870:Gene Expression; D005798:Genes, Bacterial; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D012481:Salmonella Infections, Animal / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control; D012486:Salmonella typhimurium / Q000235:genetics* / Q000276:immunology*; D014435:Typhoid Fever / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control
chemical_list: D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D004269:DNA, Bacterial