BACKGROUND

Toxocariasis is an important zoonotic infection, especially in tropical areas. One of the significant challenges in the serodiagnosis of human toxocariasis is the cross-reaction of antigens with other parasites due to their relatively similar glycan structures. Removing the glycan structure from excretory-secretory (TES) antigens may increase the efficacy of these antigens in the diagnosis of toxocariasis. The current study aimed to assess the efficacy of deglycosylated excretory-secretory (dTES) antigens for the serodiagnosis of human toxocariasis.

METHODS

ES antigens were prepared from second-stage larvae and deglycosylated using sodium hydroxide (NaOH). The TES antigens, along with the dTES antigens, were used in an ELISA as well as a western blotting system for the detection of anti- antibodies. Sera samples collected from 30 confirmed cases of toxocariasis, 30 patients with other diseases, and 30 healthy subjects were evaluated by both systems.

RESULTS

The sensitivity of TES and dTES ELISA for the diagnosis of human toxocariasis was 96.67% (95% CI = 82.78-99.92) and 93.33% (95% CI = 77.93-99.18), respectively, while the specificity of dTES (88.33%; 95% CI = 77.43-95.18) increased significantly compared to the TES (80.00%; 95% CI = 67.67-89.22). The sensitivity of both antigens was 100% (95% CI = 88.43-100) by the western blotting system. Moreover, the specificity of TES and dTES antigens was 95% (95% CI = 86.08-98.96) and 98.33% (95% CI = 91.06-99.96), respectively, when using the western blotting system.

CONCLUSION

Results of the current study indicate that the chemical removal of the glycan epitopes of ES antigens significantly reduces cross-reactivity rates with other parasitic infections. Considering the findings of the present study, the dTES antigens seem to be suitable antigens for the serodiagnosis of human toxocariasis.