Development of a murine infection model with Leishmania killicki, responsible for cutaneous Leishmaniosis in Algeria : application in pharmacology

In Algeria, Leishmania infantum, Leishmania major, and Leishmania killicki (Leishmania tropica) are responsible for cutaneous leishmaniosis. We established a murine model of L. killicki infection to investigate its infective capacity, some immunophysiopathological aspects, and its suitability for pharmacological purposes. Following the injection of L. major or L. killicki metacyclic promastigotes in the ear dermis of BALB/c mice, the course of infection was followed. The infection with L. killicki caused slower lesion formation than with L. major. The presence of L. killicki or L. major DNA and parasites was detected in the ear dermis and in lymph nodes, spleen, and liver. Lesions induced by L. killicki were nonulcerative in their aspect, whereas those caused by L. major were highly ulcerative and necrotic, which matches well with the lesion phenotype reported in humans for L. killicki and L. major, respectively. The treatment of L. killicki lesions by injection of Glucantime (R) significantly reduced the lesion thickness and parasite burden. Ear dermal injection of BALB/c mice constitutes a model to study lesions physiopathology caused by L. killicki and presents interest for in vivo screening of new compounds against this pathogen, emerging in Algeria

Leishmania infantum MON-1 : seul zymodème isolé chez les chiens leishmaniens en Tunisie

International audienceIso-enzymatic characterization of 19 Leishmania strains isolated from Tunisian dogs revealed that all correspond to Leishmania infantum MON-1. This confirms the role of dog as a reservoir of the commonest zymodeme responsible for human visceral leishmaniasis in the Mediterranean basin. However, and in spite of the high number of identifications, many zymodemes, mainly the dermotropic ones as Leishmania infantum MON-24, frequently reported in humans, had never been isolated from dogs. The study of their cultural characteristics may contribute to explain the particular iso-enzymatic profile of dogs strains.Dix-neuf souches de leishmanies, isolées chez des chiens originaires de différentes régions de la Tunisie, ont été typées par électrophorèse des iso-enzymes. Toutes se sont révélé correspondre à Leishmania infantum MON-1, confirmant la prédominance de ce zymodème chez cet animal. L’absence, aussi bien dans cette série que dans celles d’autres pays méditerranéens, de certains zymodèmes dermotropes, fréquemment rencontrés chez l’homme, pose le problème de leur réservoir. La multiplication des isolements chez les hôtes potentiels et l’étude de la cinétique en culture des différents zymodèmes pourraient apporter d’éventuelles réponses

Identification of Leishmania at the species level with matrix-assisted laser desorption ionization time-of-flight mass spectrometry

AbstractMatrix-assisted laser desorption ionization time-of-flightMALDI-TOF mass spectrometry (MS) is now widely recognized as a powerful tool with which to identify bacteria and fungi at the species level, and sometimes in a rapid and accurate manner. We report herein an approach to identify, at the species level, Leishmania promastigotes from in vitro culture. We first constructed a reference database of spectra including the main Leishmania species known to cause human leishmaniasis. Then, the performance of the reference database in identifying Leishmania promastigotes was tested on a panel of 69 isolates obtained from patients. Our approach correctly identified 66 of the 69 isolates tested at the species level with log (score) values superior to 2. Two Leishmania isolates yielded non-interpretable MALDI-TOF MS patterns, owing to low log (score) values. Only one Leishmania isolate of Leishmania peruviana was misidentified as the closely related species Leishmania braziliensis, with a log (score) of 2.399. MALDI-TOF MS is a promising approach, providing rapid and accurate identification of Leishmania from in vitro culture at the species level

Development of a murine infection model with Leishmania killicki, responsible for cutaneouslLeishmaniosis in Algeria : application in pharmacology

In Algeria, Leishmania infantum, Leishmania major, and Leishmania killicki (Leishmania tropica) are responsible for cutaneous leishmaniosis. We established a murine model of L. killicki infection to investigate its infective capacity, some immunophysiopathological aspects, and its suitability for pharmacological purposes. Following the injection of L. major or L. killicki metacyclic promastigotes in the ear dermis of BALB/c mice, the course of infection was followed. The infection with L. killicki caused slower lesion formation than with L. major. The presence of L. killicki or L. major DNA and parasites was detected in the ear dermis and in lymph nodes, spleen, and liver. Lesions induced by L. killicki were nonulcerative in their aspect, whereas those caused by L. major were highly ulcerative and necrotic, which matches well with the lesion phenotype reported in humans for L. killicki and L. major, respectively. The treatment of L. killicki lesions by injection of Glucantime (R) significantly reduced the lesion thickness and parasite burden. Ear dermal injection of BALB/c mice constitutes a model to study lesions physiopathology caused by L. killicki and presents interest for in vivo screening of new compounds against this pathogen, emerging in Algeria