Avaliação de diferentes lotes de soro bovino fetal no preparo de meio para cultura de Leishmania (Viannia) braziliensis

• Autor(a) principal: Santos, Jéssica Cristina dos
• Data de Publicação: 2015
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/4630
• topic: Leishmania (Viannia) braziliensis; Promastigotas; Meio de Grace; Leishmania (Viannia) braziliensis; Promastigotas; Grace´smedium; CIENCIAS BIOLOGICAS::PARASITOLOGIA

Promastigote forms of Leishmania (V.) braziliensis can be mantained in vitro for use in research. The bovine fetal serum (BFS) is an important component in several culture medium, however, its composition varies from batch to batch. This work aims to evaluate the performance of different BFS batches for preparation of Leishmania (V.) braziliensis culture media, comparing information supplied by different known techniques. PPS6m and CSA7c leishmanias strains were from samples obtained from American Tegumentary Leishmaniasis (ATL) patients and five different batches of BFS were tested in Grace’s medium. The parasite growth curve was evaluated by a daily hemocitometer counting, the metabolism was evaluated by the parasite’s ability to metabolize 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), the percentage of promastigote metacyclic forms was quantified by an agglutination test using Bauhinia purpuera (BPL) lectin and the ability to promote mice lesions evaluated by a weekly measurement of lesions. The biochemical components of the BFS batches was also performed. It was observed that two or more passages in culture were necessary to identify bad batches of BFS by the growth curve analysis, while the metabolic analysis showed that an inadequate BFS batch of provided a metabolic rate higher or equal to the best BFS batch. A lower percentage of metaciclic forms of PPS6m strain was observed in one of the media, however, the percentage of metacyclic promastigotes was similar among all the CSA7c culture media, independently of the parasite number. Besides, the stationary phase parasite’s ability to cause lesions in BALB/c mice did not depend on the SBF batch present in the cultures. Data reveals that the best method to select good culture serum is to observe the growth curve for two or more passages, besides this, bad SBF batches are able to produce parasites with the same ability to infect mice.