Diagnotic value of some Fasciola gigantica antigens.

The present study was aimed to select the specificity of antigens for Fasciola gigantica depending on its diagnostic utility and field applications. The tested antigens were coproantigen, excretory-secretory (ES) antigen and egg antigen. Coproantigen and Copro Hyperimmune serum were able to reflect the lowest level of cross-reaction with other tested F. gigantica antigens. By using SDS-PAGE, a structural homology was observed in F. gigantica ES and egg antigens. Intense cross reaction was observed between ES and egg antigens by ELISA technique even when there was no cross-reaction with coproantigen. The 27.6 kDa band proved to be the most specific in F. gigantica coproantigen and was different from the band at the same molecular weight by ES antigen. The results conclude that coproantigens show specific diagnostic ability for Fasciola and have low numbers of cross-reaction proteins reflecting its high specificity. Moreover, detection of coproantigen in faeces offers a new potential for diagnostics as compared to serum samples. This fact holds promise for a more accurate diagnostic technique in the near future for suspected Fasciola infection.