Development of a Universal IPMA Test to Detect Lawsonia Antibodies in Multiple Species Using Protein A and G

A recombinant protein combining the immunoglobulin binding sites of Proteins A and G, conjugated with horseradish peroxidase was used as a universal detection reagent for the assessment of antibodies against Lawsonia intracellularis. The reagent was applied in an indirect immunoperoxidase method in microplates for detection of antibodies to smooth lipopolysaccharide antigen in sera from horse and pig. Also, using protein G and protein A separately which detected from results that is species specific. An added advantage was that a universal conjugate using the proteins A and G detection reagent could be established.