Excretory-secretory antigens from adult Nematospiroides dubius

Adult Nematospiroides dubius excretory-secretory (ES) products were collected from worms cultured in vitro, radiolabelled and separated by sodium dodecyl polyacrylamide gel electrophoresis (SDS-PAGE). The components were characterized and assessed for molecular weight (MW) after autoradiography and gel staining, for antigenicity in immunoblots, for sensitivity to protease enzymes, and for carbohydrate content. ES contained at least 18 denatured components from MW less than 20,000 to greater than 200,000. At least one of the surface proteins of adults was found with the ES antigens recovered when adults were cultured in vitro. Molecules with MW 200,000, 78,000 and 60,000 were glycoproteins and reacted with immune mouse serum in Western blots. The dominant ES, MW 60,000 component stained with periodic acid-Schiff (PAS), bound lectins with affinity for D-mannose, and was resistant to peptic and tryptic but not V8 protease digestion.