Diagnotic value of some Fasciola gigantica antigens

Abstract

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.

Dynamics of Haemonchus Contortus Coproantigen Appearance in Feces of Experimentally Infected Sheep

“…Immunodiagnostic assays used for antigen detection have better superiority over others, as they have precise and sensitive ability for early detection of the infection at the prepatent period. Moreover, the detection of coproantigen remains a promising tool for usage in large-scale laboratories or epidemiological studies as it overcomes the problem of cross-reactivity, false negativity, and could be used to monitor the efficacy of treatment of such diseases [14][15][16][17]. Even though diverse diagnostic techniques for haemonchosis were narrated using different types of H. contortus antigen in enzyme linked immunosorbent assay (ELISA) [8,18], a knowledge gap about characterization and usage of coproantigen for early diagnosis is still present.…”

“…Coproantigen capture ELISA Antigen-capture ELISA was performed to monitor the kinetics of appearance of the H. contortus coproantigen in feces of the experimentally infected lambs according to the experimental design of Shalaby et al [15]. Ninetysix well microtiter plates were incubated with 100 µl/ well with rabbit monospecific anti-H. contortus serum at the dilution 1:20 in coating buffer, PH 9.6, at 37 °C for 1 hr, then at 4 °C overnight.…”