Análise da expressão das proteínas META2, LRR17, STI1 e TSA em isolados de Leishmania (Viannia) braziliensis obtidos de pacientes com lesão cutânea ou mucosa

• Autor(a) principal: Ávila, Lucilla Ribeiro
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/4566
• topic: TSA; STI; Meta-2; Leshimania (Viannia) braziliensis; Mucosal leishmaniasis; TSA; STI; Meta-2; Leishmania (Viannia) braziliensis; Mucosal leishmaniasis; CIENCIAS DA SAUDE::SAUDE COLETIVA

Introduction: Leishmania (Viannia) braziliensis is the most common etiologic agent of cutaneous leishmaniasis in Brazil. About 1 to 10% of patients infected with this species of parasite develop the mucosal leishmaniasis, whose lesions are progressive, destructive and are characterized by a strong specific immune response. The mechanisms for the development of mucosal leishmaniasis are poorly known, but it is possible that proteins associated with virulence of the parasite, such as META2 LRR17 and/or related with the induction of a strong immune response, such as STI and TSA, participate in the pathogenesis disease, causing the appearance of metastases in the mucosa. Objective: To evaluate the expression of proteins META2, LRR17, STI1 and TSA in promastigotes and amastigotes of Leishmania (Viannia) braziliensis derived from cutaneous or mucosal lesions. Methods: It was used three isolates from cutaneous lesions of patients (JCJ8c, and RPL5c SMB7c) and three isolates from mucosal lesions (ASL9m, and JBC8m PPS6m). Amastigotes of the isolates were obtained after inoculation of biopsies in mice knockout in interferon gamma and promastigotes in logarithmic or stationary phase obtained in culture in Grace's medium. The kinetics of growth in culture of isolates was performed by counting daily over ten days in the flow cytometer. The expression of proteins of each isolate was assessed by immunoblotting technique and by flow cytometry, the latter being used only to evaluate the expression of proteins whose expression was significant difference between isolates from cutaneous or mucosal lesions. Results: Promastigotes in stationary phase of the isolates SMB7c and JBC8m were the most expressed the protein META2. The greatest expression of this protein in parasites coincided with more severe lesions, since despite of isolated SMB7c being of cutaneous origin, the patient also presented mucosal lesion, and in the isolated JBC8m the patient presented return of lesions. Proteins LRR17 and STI1 were not expressed in significant amount in both promastigotes and amastigotes of different isolates. TSA protein was expressed at higher levels in promastigotes stationary phase and amastigotes of the xi isolates from patients with mucosal lesions, and this difference was also observed in flow cytometric analysis. Conclusion: The results suggest an association of META2 protein, which is related to the virulence of the parasite, with the generation of more severe lesions in the mucosal, since the highest expression of the protein was isolate from patients with mucocutaneous lesions and patients whose treatment was not effective. TSA, which is associated with antigenicity and virulence of the parasite was also expressed in greater amount in isolates from patients with mucosal lesions. The hypothesis is that, despite TSA protein to induce a protective immune response could be conferring protection in the Leishmania after entering the phagolysosomes by being an antioxidant protein. This protection favored the persistence of parasites and later generation of mucosal lesions.