title: Cell-surface properties of Lactococcus garvieae strains and their immunogenicity in the yellowtail Seriola quinqueradiata.
abstract: The cell-surface properties of strains of Lactococcus garvieae were examined. Two capsular types were found, one with a highly developed capsule (KG9408) and one with a micro-capsule (MS93003) carrying fimbriae-like components projecting from the cell surface. One strain (NSS9310) had neither cell capsular nor fimbriae-like structures on its cell surface. The strains with the highly developed capsule were more virulent to fish than either the micro-capsular or non-capsular strains. The KG9408, MS93003 and NSS9310 strains could be clearly differentiated by their susceptibility to bacteriophages. Protection against L. garvieae infection was induced in the yellowtail Seriola quinqueradiata by immunization with formalin-killed L. garvieae KG9408 and MS93003 cells. Although protection was also induced by immunization with NSS9310, the level of protection was significantly lower than that with KG9408 and MS93003 vaccines. Passive immunization with yellowtail immune sera raised against KG9408 and MS93003 conferred strong protection on yellowtail with rapid bacterial clearance after challenge with L. garvieae. Immunoblotting analysis of protein antigens extracted from L. garvieae strains using rabbit anti-KG9408 and anti-MS93003 sera and yellowtail anti-KG9408 and anti-MS93003 sera indicated that some bands in KG9408 and MS93003 strains were not detectable in NSS9310.
authors.affiliation: Miyazaki Prefectural Fisheries Experimental Station, Miyazaki Prefecture, Aoshima, Miyazaki 6-16-3, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ooyama
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hirokawa
authors.forename: Takayuki
authors.initials: T
authors.lastname: Minami
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yasuda
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Nakai
authors.forename: Makoto
authors.initials: M
authors.lastname: Endo
authors.forename: Lila
authors.initials: L
authors.lastname: Ruangpan
authors.forename: Terutoyo
authors.initials: T
authors.lastname: Yoshida
mesh_terms: D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000276:immunology; D016667:Bacterial Capsules / Q000276:immunology*; D001428:Bacterial Vaccines; D002473:Cell Wall / Q000737:chemistry; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology* / Q000517:prevention & control; D016908:Gram-Positive Bacterial Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D007106:Immune Sera / Q000097:blood; D007116:Immunization, Passive / Q000662:veterinary; D017045:Lactococcus / Q000276:immunology* / Q000472:pathogenicity / Q000648:ultrastructure; D010473:Perciformes; D010641:Phenotype; D014774:Virulence
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D007106:Immune Sera