A monoclonal antibody diagnoses active Fasciola infection in humans.

Monoclonal antibodies (MABs) were produced after fusion of spleen cells of Fasciola antigen immunized BALB/c mice and non secreting murine myloma cells (P3x63 Ag8). Six MAbs, showing the highest reactivity with purified Fasciola antigen, were prepared. All 6 MABs were IgG2 with Kappa light chain. Reactive epitopes recognized by the six MAbs were glycoprotein in nature, and each MAb recognized a single epitope of Fasciola antigen. No cros reactions were observed with Schistosomal AWSA, hydatid Ag and Entamoeba Ag. EITB technique showed a specific diagnostic band at 17.5 kDa for each of the six MAbs. Anti-Fasciola MAb (AD2) was conjugated with peroxidase and was used with anti-rabbit anti-Fasciola polyclonal antibody in sandwich-ELISA to detect circulating Fasciola antigen in serum and urine samples of 57 fascioliasis patients, 51 schistosomiasis patients, 45 patients infected with other parasites and 47 healthy controls. Sensitivity of the assay in detection of circulating Fasciola antigen in sera and urines of Fasciola infected patients was 100%. The specificity of the assay was calculated among patients infected with schistosomiasis and other parasites and was 98% in serum and 97% in urine. A positive correlation was found between levels of circulating Fasciola antigen in serum and urine samples of fascioliasis patients (r = 0.825, p < 0.05).