Evaluation of enzyme-linked immunoelectrotransfer blot test using purified native antigen mix from cisticercus fluid of Taenia solium for diagnosis of human cysticercosis

Abstract

Objectives. Evaluate the efficiency of the enzyme-linked immunoelectrotransfer blot test (EITB) for the detection of human cysticercosis using purified native antigen mix from cysticercus fluid of Taenia solium. Material and methods. Observational study of the evaluation of the diagnostic test. The purified native antigen mix was extracted from the fluid of cysticercus from naturally parasitized pigs from areas considered endemic. Four purification methods were evaluated and one was selected: ammonium sulfate, lentil lectin-Sepharose, Sephadex G-75 and Electro-elution. The sensitivity of the purified antigen was determined with EITB and was evaluated with 50 sera positive for cysticercosis and the specificity with 50 sera negative for cysticercosis (20 free of parasitic infection and 30 positive for different parasites). Results. The optimal concentration of the purified native antigen mix to prepare the EITB strips was 0.82 μg/mm. By affinity chromatography with Lentil Lectin-Sepharose we visualized and purified 8 specific antigenic glycoproteins, their relative masses being: 13, 14, 17, 18, 23, 24, 31 and 35 kDa. The purified antigens obtained by the other methods were not evaluated by EITB because they did not correspond to the specific antigenic proteins considered between 13 and 35 kDa. The EITB test using purified native antigen mix showed 100% sensitivity and 100% specificity. Conclusions. The purified antigen native mix improved the diagnostic efficiency of the EITB test. We recommend the preparation of an in-house kit and field validation so that it can be transferred and implemented in laboratories in endemic areas of Peru.