Application and evaluation of enzyme-linked immunosorbent assay and immunoblotting for detection of antibodies toTreponema hyodysenteriaein swine

Abstract

SUMMARYAn enzyme-linked immunoassay (ELISA) has been developed to detect serum Immunoglobulin antibodies G and M toTreponema hyodysenteriaein vaccinated, experimentally infected and naturally infected swine. Naturally infected swine gave ELISA titres that were similar to experimentally infected swine, but were significantly less than the titres of vaccinated swine. When serum from naturally infected swine was used to probe nitrocellulose blots of sodium dodecyl sulphate–polyacrylamide gel electrophoresed whole cell proteins ofT. hyodysenteriae,the immunoblotting patterns showed IgG antibodies were produced against manyT. hyodysenteriaeprotein antigens and against lipopolysaccharide (LPS). The IgG antibodies directed against LPS were serotype-specific for that LPS and could be used to identify the serotype involved in theT. hyodysenteriaeinfection in that herd. IgM immunoblots also reacted with the many protein antigens but were less specific for LPS antigen, with a substantial degree of crossreaction between the LPS of all serotypes.The data demonstrate that a microplate enzyme-linked immunosorbent assay, coupled with immunoblotting, is a very specific and sensitive test for detection of antibody toTreponema hyodysenteriaein swine.