Identification and evaluation of antigenic epitopes of total soluble extract and adult worm vomit for immunodiagnosis of human fascioliasis

ABSTRACT

Fascioliasis is an important worldwide herbivores infection with increasing evidence of prevalence as a human disease. There is an important necessity to develop sensitive and specific diagnostic tools for early treatment and to avoid complications. This study is directed to identify, characterize and evaluate the immunodiagnostic potential of the total soluble extract [TSE] and the adult worm vomit [AWV] antigens of worm using immunoblotting of total IgG and IgG4. Sixty individuals, 29 positive for fascioliasis by IHAT [Group I], 15 positive for other parasitic infections [Group II] and 16 normal controls [Group III], were included. Both TSE and AWV antigens were analyzed by SDS-PAGE. All sera were immunoblotted against the two antigens using total IgG and IgG4. Total IgG immunoblotting using TSE antigen at 62 kDa gave sensitivity, specificity, positive value predictive [PVP] and accuracy of 72.5%, 100%, 100% and 82.2%, respectively. These values were 62.5%, 100%, 100% and 81.2%, respectively with AWV antigen at 56 kDa. IgG4 immunoblotting using TSE antigen gave sensitivity, specificity, PVP and accuracy of 100%, 93.3%, 96.6% and 97.8%, respectively at 60 kDa, while AWV antigen gave no reaction with IgG4 antibody. Total IgG immunoblotting using TSE antigen at 62 kDa and AWV antigen at 56 kDa proved to be valuable as diagnostic tests for human fascioliasis