Applicability of ELISA with different antigens to diagnose varying levels bovine cysticercosis

Resumo

The efficiency of larval Taenia crassiceps (Tcra) antigens was evaluated by enzyme-linked immunosorbent assay (ELISA) to diagnose bovine cysticercosis. Three types of antigens were evaluated: total (T), total sonicated (Ts), and membrane (M); these samples included positive and negative control sera for cysticercosis, as well as sera for other pathologies. The sensitivity rates of ELISA were determined to be 85.0 and 81.25% for T antigen, 82.5 and 78.75% for Ts antigen, and 80.0 and 80.0% for M antigen, using cut-off points with standard deviations (SD) of 2 and 3, respectively; the specificity rates of ELISA were 47.5 and 58.75% for T antigen, 65.0 and 73.75% for Ts antigen, and 58.75 and 62.5% for M antigen, using 2 and 3 SD cut-off points, respectively. These results demonstrated that ELISA, which displayed a better performance in the detection of experimentally infected animals, had a higher sensitivity than the anatomical and pathological examination performed (during routine post-mortem inspections) in other studies. However, the post-mortem investigation is highly specific, and the specificity was higher than that of ELISA. Therefore, a combination of these diagnostic tests must be utilized for the accurate detection of bovine cysticercosis, demonstrating the practical applicability of ELISA.