Biochemical characterization of an antigenic saline extract of Actinobacillus pleuropneumoniae serotype 5 and identification of a serotype-specific antigen for ELISA serodiagnosis.
A saline extract of boiled-formalinized whole cells from a local strain (81-750; Quebec, Canada) of Actinobacillus pleuropneumoniae, serotype 5b was used as an antigen in an enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of swine pleuropneumonia. Characterization of this crude extract was done and proteins, neutral sugars, hexosamines, and 2-keto-3-deoxyoctonate (KDO) were evaluated. On phenol extraction of the crude extract a serotype-specific antigen of polysaccharidic nature was recovered from the aqueous phase. This antigen was characterized using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with Coomassie blue, silver and Schiff stainings. Immunoblots were done using sera of experimentally infected pigs that showed serotype specificity and cross-reactivity. Overall, the results indicate that the O-chain of lipopolysaccharides is a specific antigen that could be used in ELISA for the serodiagnosis of serotype 5 of A. pleuropneumoniae.
Radacovici
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Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de médecine vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
Lallier
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R
Larivière
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S
Dubreuil
J D
JD
D000189:Actinobacillus Infections / Q000175:diagnosis / Q000662:veterinary*; D016977:Actinobacillus pleuropneumoniae / Q000276:immunology*; D000818:Animals; D000942:Antigens, Bacterial / Q000737:chemistry* / Q000276:immunology; D015153:Blotting, Western; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D019286:Endopeptidase K; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000737:chemistry / Q000276:immunology; D010636:Phenols; D011001:Pleuropneumonia / Q000175:diagnosis / Q000662:veterinary*; D011135:Polysaccharides, Bacterial / Q000737:chemistry; D012697:Serine Endopeptidases / Q000378:metabolism; D012965:Sodium Chloride; D013552:Swine; D013553:Swine Diseases / Q000175:diagnosis*
D000942:Antigens, Bacterial; D000939:Epitopes; D010636:Phenols; D011135:Polysaccharides, Bacterial; D012965:Sodium Chloride; D012697:Serine Endopeptidases; D019286:Endopeptidase K