Characterization of Excretory and Secretory Larval Antigen of Toxocara canis by Western Blotting

Toxocara canis is a dog helminth which causes visceral larva migrans (VLM) in humans. The identification of specific antigens of T. canis is important in order to develop better diagnostic techniques. The excretory-secretory larval antigens of T. canis (ESLA) were prepared by in vitro culturing of T. canis larvae in RPMI 1640 medium. These antigens were separated using sodium dodecyl sulphate-poly acrylamide gel electrophoresis (SDS-PAGE) which revealed 9 protein bands at a molecular weight of 17, 18, 22, 24, 26, 28, 30, 32 and 120 kDa. The immuno reactivity of excretory-secretory larval antigens of T. canis was checked by Western blotting using hyper immune serum raised in rabbits against ESLA antigen which showed six immuno reactive bands at a molecular weight of 17, 18, 22, 24, 30 and 32 kDa. These antigens merit further evaluation as candidate for use in diagnosis of toxocariasis in humans and adult dogs.