title: Serological cross-reactivity between Brucella abortus and yersinia enterocolitica 0:9: IV. Evaluation of the M- and C-epitope antibody response for the specific detection of B. abortus infections.
abstract: Smooth lipopolysaccharides (SLPS) from Brucella abortus contain A-epitopes against which the majority of serum antibodies are directed during infections. SLPS from Yersinia enterocolitica 0:9 possesses identical epitopes, which are the cause for serological cross-reactivity. All Brucella spp. possess M- and C-epitopes which are not present in Y. enterocolitica 0:9. In order to examine the usefulness of these M- and C-epitopes for discriminatory serological testing, a panel of sera were used in this study, comprising sera from Y. enterocolitica 0:9-infected heifers, sera from B. abortus-infected cattle of comparable strength in the serological brucellosis tests to the sera from Y. enterocolitica 0:9-infected heifers, sera from B. abortus-infected bovines with strong serological reactions and sera from animals free from B. abortus or Y. enterocolitica infections. These sera were tested in blocking ELISAs with seven M- and one C-epitope-specific monoclonal antibodies in combination with SLPS from B. melitensis M16 high in M-epitopes as antigen. Strong B. abortus sera inhibited most strongly, while negative sera showed no or little inhibition. Sera with weak or intermediate titres blocked to a lower extent. Unexpectedly, the sera from Y. enterocolitica 0:9-infected heifers showed inhibition behaviour virtually identical to the comparable sera from B. abortus infected animals. Absorbing out of the A-epitope specific serum antibodies with either Y. enterocolitica 0:9 SLPS or with Y. enterocolitica 0:9 bacteria, indicated the presence of M- or C-epitope-specific serum antibodies in some sera from B. abortus-infected cattle but not in the sera from Y. enterocolitica 0:9-infected animals. These results demonstrate that the M- or C-epitope-specific antibody response in sera from B. abortus infected cattle is only of limited value for the serological discrimination between B. abortus and Y. enterocolitica 0:9 infections.
authors.affiliation: Central Animal Health Laboratory, Wallaceville Animal Research Centre, Upper Hutt, New Zealand. kittelbergerr@wallaceville.mqm.govt.nz
authors.forename: R
authors.initials: R
authors.lastname: Kittelberger
authors.forename: P G
authors.initials: PG
authors.lastname: Bundesen
authors.forename: A
authors.initials: A
authors.lastname: Cloeckaert
authors.forename: I
authors.initials: I
authors.lastname: Greiser-Wilke
authors.forename: J J
authors.initials: JJ
authors.lastname: Letesson
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D002003:Brucella abortus / Q000276:immunology*; D002007:Brucellosis, Bovine / Q000175:diagnosis* / Q000276:immunology; D002417:Cattle; D002418:Cattle Diseases; D003168:Complement Fixation Tests; D003429:Cross Reactions; D003937:Diagnosis, Differential; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000032:analysis*; D005260:Female; D008070:Lipopolysaccharides / Q000276:immunology*; D012680:Sensitivity and Specificity; D015009:Yersinia Infections / Q000175:diagnosis / Q000276:immunology / Q000662:veterinary*; D015008:Yersinia enterocolitica / Q000276:immunology*
chemical_list: D000939:Epitopes; D008070:Lipopolysaccharides