title: Immune responses dependent on antigen location in recombinant attenuated Salmonella typhimurium vaccines following oral immunization.
abstract: The subcellular location of a recombinant antigen in recombinant attenuated Salmonella vaccines may influence immunogenicity dependent on exposure of the recombinant antigen to cells involved in systemic immune responses. It has been shown that a recombinant attenuated Salmonella vaccine secreting the recombinant Streptococcus pneumoniae PspA (rPspA) antigen specified by pYA3494 induced protective anti-rPspA-specific immune responses (Kang et al. (2002) Infect. Immun. 70, 1739-1749). A recombinant plasmid pYA3496 specifying a His(6)-tagged rPspA (His(6)-rPspA) protein (no apparent signal sequence) caused the rPspA antigen to localize to the cytoplasm of Salmonella. Salmonella vaccines carrying pYA3494 or pYA3496 expressed similar amounts of rPspA. After a single oral immunization in BALB/c mice with 10(9) colony-forming units (CFU) of the recombinant Salmonella vaccines carrying pYA3494 or pYA3496, IgG antibody responses were stimulated to both rPspA and Salmonella lipopolysaccharide (LPS) antigens. The anti-rPspA IgG titer induced by Salmonella carrying pYA3494 (1.9 x 10(7)) was 10(4) times higher than induced by Salmonella carrying pYA3496 (<2.4 x 10(3)).
authors.affiliation: Department of Biology, Washington University, Campus Box 1137, One Brookings Dr., St. Louis, MO 63130-4899, USA.
authors.forename: Ho Young
authors.initials: HY
authors.lastname: Kang
authors.forename: Roy
authors.initials: R
authors.lastname: Curtiss
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000276:immunology* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D005260:Female; D008070:Lipopolysaccharides / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D022562:Salmonella Vaccines / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology*; D012486:Salmonella typhimurium / Q000235:genetics / Q000276:immunology*; D013347:Subcellular Fractions / Q000378:metabolism*; D014611:Vaccination; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D008070:Lipopolysaccharides; D022562:Salmonella Vaccines; D014613:Vaccines, Attenuated; D014614:Vaccines, Synthetic; C051592:pneumococcal surface protein A