CARBOHYDRATE EPITOPES ON HAEMONCHUS-CONTORTUS ANTIGENS

Extracts of infective larvae and adults of the trichostrongylid Haemon chus contortus were studied for the presence of carbohydrate moieties. Several different lectin-binding sites were demonstrated in both stag es using a panel of nine lectins. The carbohydrate specificity of the lectins used strongly suggests that alpha-D-mannose, alpha-D-glucose, and D-N-acetylglucosamine are the most important carbohydrate epitopes present on H. contortus proteins. Thus, N-linked oligosaccharides for m the major part of the carbohydrate moieties on these glycoproteins. Treatment with sodium periodate was performed to investigate the immun oreactivity towards the carbohydrate moieties. This treatment resulted in a reduction in the immunoreactivity of these antigens as demonstra ted by enzyme-linked immunosorbent assay (ELISA) and immunoblotting, s uggesting that a substantial part of the host immune response against H. contortus is directed against the carbohydrate epitopes on the para site antigens.