Screening of clinical isolates of Leishmania sp. for genome sequencing

Abstract

The protozoans of genus Leishmania are parasite species capable of causing a group of disease known as leishmaniasis. The parasite's transmission to a vertebrate host is dependent on a flebotomine vector. Visceral leishmaniasis (VL), among all the clinical manifestations of leishmaniasis, is the most lethal type of the disease due to causing severe damages to organs as spleen, liver and bone marrow. Tropical regions such as Middle East, South of Asia, Europe, Central America and South America are endemic to VL, striking in huge proportions countries like Brazil (90% of cases in the Americas). As a neglected disease, treatments are poorly developed and the number of fatalities is evident among all ages. The Brazilian Northeast is a very endemic area to VL, being the most affected region by the disease, occurring a huge risk to the infected population. The disease development is related to parasite/host interface factors. Genome analyses of clinical isolates of Leishmania enable to understand which factors intrinsic to the parasites genetic diversity are related to disease outcome and response to treatment. Thus, the main aim of this project is to perform the screening of clinical isolates from patients diagnosed with VL in Aracajú-Sergipe, in order to select which samples will be sent to Whole-Genome Sequencing (WGS) through Illumina platform to get the complete genomic sequences of parasites capable of causing VL in this endemic area. The screening methods will encompass the parasite morphological analysis, as well as the molecular characterization of conserved genomic regions through DNA sequencing analysis and Molecular Phylogenetics. Engendered data will be useful for constructing an informative panel about analyzed samples, which will guide to the selection of clinical isolates for genome sequencing. Furthermore, as a secondary aim for the project, we will systematize the genome-sequenced data analyses obtained from previous clinical isolates, which will assist the Comparative Genomic analyses of Leishmania to our group's further studies. (AU)