title: Evaluation of an indirect enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to the Apx toxins of Actinobacillus pleuropneumoniae.
abstract: The reference strains of the 12 serotypes of Actinobacillus pleuropneumoniae express one or two of three different RTX exotoxins designated Apx I, Apx II and Apx III. The toxins are important virulence factors. In the present study, ELISAs with purified Apx I, Apx II and Apx III, respectively, as antigen were evaluated as candidates for serological diagnosis of Actinobacillus pleuropneumoniae infection in pigs. The pigs were inoculated with biotype 1, serotypes 1-12, and biotype 2, serotype 14, respectively. A strong humoral antibody response was seen to all the three antigens in most pigs irrespective of the serotype used for inoculation. However, titers to the exotoxins secreted by the serotype used for inoculation were generally highest. The results show that toxin proteins of Actinobacillus pleuropneumoniae are antigenically related and that a correlation between serotype and secretion of exotoxin is not revealed serologically in the ELISA test.
authors.affiliation: Danish Veterinary Laboratory, Copenhagen, Denmark.
authors.forename: R
authors.initials: R
authors.lastname: Nielsen
authors.forename: J F
authors.initials: JF
authors.lastname: van den Bosch
authors.forename: T
authors.initials: T
authors.lastname: Plambeck
authors.forename: V
authors.initials: V
authors.lastname: Sørensen
authors.forename: J P
authors.initials: JP
authors.lastname: Nielsen
mesh_terms: D000189:Actinobacillus Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary; D016977:Actinobacillus pleuropneumoniae / Q000276:immunology* / Q000472:pathogenicity; D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis*; D001426:Bacterial Proteins / Q000032:analysis / Q000276:immunology*; D001427:Bacterial Toxins / Q000032:analysis / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods / Q000662:veterinary; D006460:Hemolysin Proteins; D007106:Immune Sera; D011001:Pleuropneumonia / Q000276:immunology / Q000382:microbiology / Q000662:veterinary; D013047:Specific Pathogen-Free Organisms; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000382:microbiology; D014774:Virulence
chemical_list: D000907:Antibodies, Bacterial; C085361:ApxII toxin, bacteria; C079721:ApxIII toxin protein, Actinobacillus; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D006460:Hemolysin Proteins; D007106:Immune Sera; C087744:ApxI toxin, Bacteria