title: Importance of subunit vaccine antigen of major Fli C antigenic site of Salmonella enteritidis II: a challenge trial.
abstract: Salmonella enterica subsp. enterica serovar Enteritidis (SE) infection in chickens shows a mild pathogenicity except for young ages, compared with other animals, and laying hens sometimes produce SE-contaminated eggs leading to public health concerns. To reduce the problem, SE bacterin in poultry farms has been applied. We previously demonstrated that a subunit antigen, g.m. part polypeptide in SE-Fli C (SEp 9), could be a candidate subunit antigen of SE vaccine which may show less side effects in chickens. In this study, we used SEp 9 along with an adjuvant to inoculate chickens, then the chickens were orally challenged with SE, and suppression of the SE count in the cecum was investigated. Chickens inoculated with a commercial SE vaccine were prepared as positive controls (vaccine group), and those with physiological saline (control group) for comparison of the bacterial count after challenge. Employing two types of antibody-detection ELISA coated with either de-flagellated SE or SEp 9, specific antibody levels in blood and the intestine were determined. The bacterial count was significantly lower 1 and 3 weeks after challenge in the SEp 9 than in the control group. Specific antibody only against SEp 9 in blood but not the intestine of these birds in the SEp 9 group was detected. This study confirmed that SEp 9 antigen is a major effective antigen in SE inactivated vaccine, and it is suggested that only the subunit vaccine antigen SEp 9 is needed to effectively suppress colonization in the chicken intestine, without the need for other SE component antigens.
authors.affiliation: CAF Laboratories, 1257-1 Michinoue-Kannabe, Fukuyama, Hiroshima 720-2104, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Toyota-Hanatani
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kyoumoto
authors.forename: Eiichiroh
authors.initials: E
authors.lastname: Baba
authors.forename: Tomoya
authors.initials: T
authors.lastname: Ekawa
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Ohta
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tani
authors.forename: Kazumi
authors.initials: K
authors.lastname: Sasai
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D002432:Cecum / Q000382:microbiology; D002645:Chickens / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005407:Flagella / Q000276:immunology; D007115:Immunization Schedule; D007117:Immunization, Secondary; D007070:Immunoglobulin A / Q000096:biosynthesis / Q000276:immunology; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000276:immunology; D007422:Intestines / Q000382:microbiology; D008297:Male; D022562:Salmonella Vaccines / Q000276:immunology*; D012477:Salmonella enteritidis / Q000254:growth & development / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D022562:Salmonella Vaccines