title: Evaluation of the live vaccine efficacy of virulence plasmid-cured, and phoP- or aroA-deficient Salmonella enterica serovar Typhimurium in mice.
abstract: We evaluated the protective efficacy of 94-kb virulence plasmid-cured, and phoP- or aroA-deficient strains of Salmonella enterica serovar Typhimurium (ΔphoP or ΔaroA S. Typhimurium) as oral vaccine candidates in BALB/c mice. Two weeks after the completion of 3 oral immunizations with 1 × 10(8) colony-forming units (CFU) of virulence plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium at 10-day intervals, S. Typhimurium lipopolysaccharide (LPS)-specific mucosal secretory immunoglobulin A (s-IgA) antibody titers were detected in the cecal homogenate, bile and lung lavage fluid, but not in the intestinal lavage fluid. In addition, the increases in S. Typhimurium LPS-specific immunoglobulin G (IgG) and IgA antibody titers in the serum were also observed 2 weeks after completing 3 oral immunizations with virulence plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium. The series of 3 oral immunizations protected the mice against an oral challenge with 5 × 10(8) CFU of the virulent strain of S. Typhimurium, suggesting that both the virulence plasmid-cured, and ΔphoP and ΔaroA S. Typhimurium strains are promising candidates for safe and effective live S. Typhimurium vaccines.
authors.affiliation: Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Matsui
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Isshiki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Eguchi
authors.forename: Yohsuke
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Shimoji
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001426:Bacterial Proteins / Q000276:immunology*; D017353:Gene Deletion; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000235:genetics / Q000378:metabolism*; D012481:Salmonella Infections, Animal / Q000097:blood / Q000517:prevention & control*; D022562:Salmonella Vaccines / Q000276:immunology*; D012486:Salmonella typhimurium / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D022562:Salmonella Vaccines; C061064:PhoP protein, Bacteria