PCR-RLFP characterization of Leishmania spp. in domestic animals from the south-western border of Brazil

The aim of this study was to characterize Leishmania spp. from canine and feline samples using Polymerase Chain Reaction (PCR)- Restriction Fragment Length Polymorphism (RFLP). It was conducted in the southern region of Brazil, located at border crossings to Argentina and Uruguay. Samples were collected from 116 dogs (Canis lupus familiaris) and 89 cats (Felis catus). The PCR was performed to screen for an LT1 fragment from kinetoplast DNA (kDNA) target gene, and positive samples were subjected to a second PCR for an internal transcribed spacers (ITS1) region from ribosomal DNA (rDNA) target. RFLP was performed using the Haemophilus aegyptius (HAE III) restriction endonuclease (Fermentas (R)). Positive samples by PCR ITS1 were sequenced and deposited in NCBI GenBank, and a phylogenetic analysis was developed. We found that 12.9% (15/116) of the samples from dogs were positive. All the 89 cat samples were negative. Positive samples were tested against Leishmania reference strains presenting different patterns in PCR-RFLP, and these samples showed bands denoting similarity to the standard species of Leishmania infantum, proven through sequencing and phylogenetic analysis. The RFLP technique, alone, was shown to be feasible for practical application and confirmation of the involved Leishmania spp.