Seleção de peptídeos reconhecidos por imunoglobulinas Y anti-metacestódeo de Taenia solium por phage display

Abstract

The Taenia solium metacestodes localization in humans occours mainly in the central nervous system (CNS) promoting the disease named neurocysticercosis (NC), the most frequent parasitosis in the CNS. The pathological presentation of NC differs about localization and viability of metacestodes, and host immunological response. For its diagnosis stabelishment is necessary a right interpretation of clinical signs, neuroimagin and immunological tests, and epidemiological data. The frequent inviability of parasite material has stimutaled the development and usage of recombinant antigens in the immunodiagnosis, and since describition of the phage-display tecnology this technique has presented increseier utilization in several cientific areas, as selection of peptides that could be used for immunodiagnostic test. The aim of this study was to obtain mimetopes of T. solium through biopanning using IgY specific to T. solium metacestodes. The IgY obtained from immunizated chicken with T. solium metacetodes saline extract was coated on microplate wells to select peptides from phage library in a three rounds biopanning. The phagetopes selected were tested in NC diagnosis by ELISA assay with 110 serum samples, 40 from NC patients and patients infected with others parasitic diseases, and 30 samples of health individuals. Seven mimetopes shown the best results in diagnostic patients with NC, and also they were capable to distinguish active from inactive NC form, detecting almost even 100% of inactive NC patients. None of the clones reacted with Echinococcus granulosus sera and the specificity ranged from 85.7% to 94.3%. This study was the first utilizing chicken immunization using T. solium metacetodes saline extract. The phage clones Cc6, Cc8, Cc25, Cc27, Cc30, Cc45 e Cc48, shown the better results, can be potentials candidates as NC inactive phase markers and a uselles tool in disease prognostic, and reinforcement to neuroimaging tests.