Hemagglutination Tests with Ascaris Antigens

Abstract

Antisera against Ascaris lumbricoides var suum, Ascaris lumbricoides, Toxocara canis, and Toxocara cati were prepared in rabbits by injection of lyophilized antigen and infection with viable eggs. These antisera cross-reacted with Ascaris and Toxocara antigens in hemagglutination tests. Absorption with heterologous antigen removed cross-reacting antibodies and produced generic specific antisera. Serum obtained by injection of antigen, showed higher titers than sera obtained by infection with viable eggs. Antisera prepared against polysaccharide whole-worm antigen obtained from human and pig ascarid worms, cross-reacted with antigen prepared from these 2 worms. Absorption of these sera with both homologous and heterologous antigens reduced the titers to 0. From the data, we concluded that crude polysaccharide antigen does not exhibit species specificity. Antigens prepared from saline extracts of whole worm or tissues of pig ascarids are effective antigens in the hemagglutination test, and without preliminary absorption, antigens of Toxocara or Ascaris worms cross-react with antisera prepared against these species.