title: Th1 cells specific for a secreted protein of Listeria monocytogenes are protective in vivo.
abstract: In the present study we have investigated the role of the secreted p60 protein from Listeria monocytogenes as an Ag for CD4 T cells. The p60 protein is an abundant extracellular protein that is highly conserved within the members of the genus Listeria. Our results show that L. monocytogenes infection induces a potent p60-specific Th1 immune response. Remarkably, we found that p60-specific Th1 clones mediate significant protection against L. monocytogenes infection. For one p60-specific clone, the peptide epitope was defined. This clone recognized p60 301-312 (EAAKPAPAPSTN) in the context of the H-2Ad molecule. Despite the fact that acquired immunity against L. monocytogenes is primarily mediated by cytotoxic CD8 T lymphocytes, our data clearly demonstrate that secreted bacterial proteins are important CD4 T cell Ags and that Th1 clones specific for a secreted bacterial protein can contribute to the protection against an intracellular pathogen such as L. monocytogenes.
authors.affiliation: Institut für Medizinische Mikrobiologie und Hygiene, Fakultät für Klinische Medizin Mannheim der Universität Heidelberg, Mannheim, Germany. geginat@rumms.uni-mannheim.de
authors.forename: G
authors.initials: G
authors.lastname: Geginat
authors.forename: M
authors.initials: M
authors.lastname: Lalic
authors.forename: M
authors.initials: M
authors.lastname: Kretschmar
authors.forename: W
authors.initials: W
authors.lastname: Goebel
authors.forename: H
authors.initials: H
authors.lastname: Hof
authors.forename: D
authors.initials: D
authors.lastname: Palm
authors.forename: A
authors.initials: A
authors.lastname: Bubert
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000276:immunology*; D002999:Clone Cells / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D006183:H-2 Antigens / Q000276:immunology; D008088:Listeriosis / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D008970:Molecular Weight; D013154:Spleen / Q000166:cytology / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology / Q000378:metabolism*
chemical_list: C078516:60 kDa protein, Listeria monocytogenes; D001426:Bacterial Proteins; D016207:Cytokines; D006183:H-2 Antigens; C108513:H-2A antigen