Estudo bio-molecular de três estoques mistos de trypanosoma cruzi-leishmania spp isolados de pacientes chagásicos crônicos após terapêutica específica para a doença de chagas

• Autor(a) principal: Dias, Sueli Meira da Silva
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/3261
• topic: Trypanosoma cruz; Leishmania spp; Infecção mista; Biologia molecular; Dença de Chagas; Trypanosoma cruzi; Leishmania spp; Mixed infection; Molecular biology; Chagas disease; CIENCIAS BIOLOGICAS::PARASITOLOGIA

Thirty cronic chagasic pacients were submitted to specific treatment against Chaga’s disease. The drug of choice was Benznidazole. After treatment laboratorial exams such as parasitological and imunological aiming terapheutic validation were performed. The parasitological analysis is represented by post-treatment hemoculture of 30 cronic chagasic pacients and demonstrated the presence of promastigotes and epimastigotes in 10% (3/30) of pacients, probably characterizing a mixed infection. These hemocultures were named 371, 437 and 438. From these three pacients two were from Goias (GO) and one from Minas Gerais (MG) which are endemic regions to Chaga’s disease as well as to Leishmaniasis which justified the study of this probable co-infection. The work was developed in two phases: in the first phase it was made the biological experimental study of the mixed sotck and in the second phase it was made the confirmation of the Leishmania spp gender through PCR technique. In the experimental biological study the model used was Balb/c isogenic mice and we made an intraperitoneal inoculation of the stocks and we analysed the following parameters: parasitism, hemoculture, sorology by IFI and histopathology. The parasitism observation occured between 48 hours periods through 90 days, and the hemoculture observations occured weekly through 120 days and resulted positive only in mice innoculated with stock 371. The sorology showed anti-T. cruzi antibodies titers in mice innoculated with stocks 371 and 437. The histopathology revealed the presence of amastigotes in tissues cardiac slides from mice innoculated with stock 438, showing that only the epimastigotes forms are present in the mixed stocks and are viable to infect the experimental model used in this work. The confirmation of the Leishmania subgenus envolved in this co-infection was possible through molecular biology techniques. In PCRRFLP, after digestion of PCR products by Hae III restriction enzymes which has specific clivage sites for L. (Viannia) subgender. The samples represented by 371, 437 and 438 stocks and the controls of L. (L.) amazonensis and L. (L.) chagasi did not suffer clivage of its amplified segments in PCR. Only the control constituted by L. (V.) braziliensis suffered clivage resulting in fragments of aproximately 40 and 80 bp confirming undoubtfully that the samples represented by the mixed stocks 371, 437 and 438 isolated from cronic chagasic pacients cantained L. (Leishmania) spp.