detection of doth fasciolu gigantica circulating antigen and coproantigdn by monoctonal-based sandwich ELISA in diagnosis of human fascioliasis

ABSTRACT

Human fascioliasis is another important health challenge in Egypt. lip till now and due to many factors. its diagnosis is a problematic issue. In many eases, a considerable damage of the hepatic tissue often occurs before a proper diagnosis could he done. This in turn necessitates finding a reliable. easily applicable and locally affordable diagnostic test to overcome the diagnostic difficulties that handicap prevention and control efforts. The detection of E/S antigens in stool specimens [coproantigens] and in sera of infected humans using a MAb-based sandwich ELISA system. Stool and serum samples were collected from 35 fascioliasis patients having clinical and parasitological evidences of infection, 20 patients harboring other parasites [Schistosoma mansoni and haematobium Wuchereria bancuofti and hydatid cysts] and 25 healthy subjects. A pair of monoelonal antibodies [MAbs 9F/10B and 5F/6H], raised against both FascioIa gigantica excretory-Secretor [E/S] products and crude antigens respectively, were employed in sandwich ELISA. The lower detection limit of E/S coproantigen assay corresponded to 15 ng/ml, while that of E/S antigen assay in serum corresponded to 50ng/ml. The anti-F gigantica MAb-based sandwich ELISA for antigen detection in collected sera showed 77% sensitivity and 100% specificity with 87% diagnostic accuracy. Coproantigen detection in stool samples showed 94% sensitivity and 100% specificity with 97% diagnostic accuracy. A positive correlation was detected between antigen level in stool samples and its level in corresponding serum samples. This study showed that the use of anti-F gigantica MAb-based sandwich ELISA was more ssensitive for antigen detection in stool samples of fascioliasms patients. Than its detection in their corresponding serum samples, providing a simple, reliable, non-invasive diagnostic method for active human infection