Evaluation of Leishmania (Leishmania) chagasi strains isolated from dogs originating from two visceral leishmaniasis-endemic areas in Brazil using multilocus enzyme electrophoresis

Abstract

INTRODUCTION: Domestic dogs are the most important reservoir in the peridomestic transmission cycle of Leishmania (Leishmania) chagasi. The genetic variability of subpopulations of this parasite circulating in dogs has not been thoroughly analyzed in Brazil, even though this knowledge has important implications in the clinical-epidemiological context. METHODS: The objective of this study was to evaluate and compare the phenotypic variability of 153 L. chagasi strains isolated from dogs originating from the municipalities of Rio de Janeiro (n = 57) and Belo Horizonte (n = 96), where the disease is endemic. Strains isolated only from intact skin were selected and analyzed by multilocus enzyme electrophoresis using nine enzyme systems (6PG, GPI, NH1 and NH2, G6P, PGM, MDH, ME, and IDHNADP). RESULTS: The electrophoretic profile was identical for all isolates analyzed and was the same as that of the L. chagasi reference strain (MHOM/BR/74/PP75). Phenetic analysis showed a similarity index of one for all strains, with the isolates sharing 100% of the characteristics analyzed. CONCLUSIONS: The results demonstrate that the L. chagasi populations circulating in dogs from Rio de Janeiro and Belo Horizonte belong to a single zymodeme.

Genetic homogeneity among Leishmania (Leishmania) infantum isolates from dog and human samples in Belo Horizonte Metropolitan Area (BHMA), Minas Gerais, Brazil

“…Other studies conducted in Brazil, in general, also found low genetic variability among the studied samples [ 12 , 15 , 16 , 18 , 29 ]. Specifically, Segatto et al .…”

“…For these purposes, various molecular approaches have been used: (i) randomly amplified polymorphic DNA (RAPD) [ 14 , 20 , 21 ]; (ii) analysis of DNA regions using multilocus microsatellite typing (MLMT) [ 13 , 22 ]; (iii) simple sequence repeat (SSR)-PCR [ 14 , 23 ]; (iv) analysis using DNA hybridization probes (Southern blotting) [ 24 ] and (v) restriction fragment length polymorphism (RFLP) analysis [ 11 , 25 - 28 ]. Although the BHMA comprises municipalities with high human mortality rates, asymptomatic infection and canine prevalence, few studies have been conducted in this area to evaluate whether genetic variability exists among isolates from different hosts and clinical forms of VL [ 12 , 29 ]. Consequently, the aim of this study was to evaluate the genetic variability of L. infantum in humans (children and adults with or without Leishmania /HIV co-infection) and in dogs with different clinical forms of VL (symptomatic, oligosymptomatic and asymptomatic) in BHMA municipalities.…”

Canine β-defensin-1 (CBD1) gene as a possible marker for Leishmania infantum infection in dogs

“…These differences could also be related to differences in parasite strains infecting dogs in each studied area. This hypothesis is unlikely because L. infantum zymodeme MON-1 is the predominant strain of infecting dogs in the Mediterranean basin and apparently also in South America [24–26]. Another issue that should be considered is population stratification.…”