Central Asian Rodents as Model Animals for Leishmania major and Leishmania donovani Research

Abstract

The clinical manifestation of leishmaniases depends on parasite species, host genetic background, and immune response. Manifestations of human leishmaniases are highly variable, ranging from self-healing skin lesions to fatal visceral disease. The scope of standard model hosts is insufficient to mimic well the wide disease spectrum, which compels the introduction of new model animals for leishmaniasis research. In this article, we study the susceptibility of three Asian rodent species (Cricetulus griseus, Lagurus lagurus, and Phodopus sungorus) to Leishmania major and L. donovani. The external manifestation of the disease, distribution, as well as load of parasites and infectiousness to natural sand fly vectors, were compared with standard models, BALB/c mice and Mesocricetus auratus. No significant differences were found in disease outcomes in animals inoculated with sand fly- or culture-derived parasites. All Asian rodent species were highly susceptible to L. major. Phodopus sungorus showed the non-healing phenotype with the progressive growth of ulcerative lesions and massive parasite loads. Lagurus lagurus and C. griseus represented the healing phenotype, the latter with high infectiousness to vectors, mimicking best the character of natural reservoir hosts. Both, L. lagurus and C. griseus were also highly susceptible to L. donovani, having wider parasite distribution and higher parasite loads and infectiousness than standard model animals.

Repeated Sand Fly Bites of Infected BALB/c Mice Enhance the Development of Leishmania Lesions

“…In both experimental groups, parasites migrated from the site of inoculation (left ear) to its draining lymph nodes and skin on other body parts (contralateral ears, paws and tail) but were never detected in blood or viscera. This corresponds to the previously published pattern of development of L. major in BALB/c mice (30) while visceralisation occurs in BALB/c mice in case of unnatural intravenous or subcutaneous initiation of L. major infection or overdose of the intradermal infection (reviewed by 31). For unknown reasons, migration to eardraining lymph nodes was reduced in the second experiment in both experimental groups.…”

Identification of Kaurane-Type Diterpenes as Inhibitors of Leishmania Pteridine Reductase I

“…In the old world (southern Europe, the Middle East, southwest Asia, and Africa), approximately 20 different Leishmania species are responsible for the transmission of CL, including L tropica, L. major, L. aethiopica, L. infantum, and L. donovani , with L. major representing the most common causative organism [ 7 ]. In the new world (from the southern United States through Latin America to South America), L. mexicana , L. venezuelensis , L. amazonensis , L. braziliensis , L. panamensis , L. guyanensis, and L. peruviana are the primary causal species of CL [ 8 , 9 ]. In Colombia, the overall leishmaniasis incident rate is 26.2 cases per 100,000 population (including 98.6% of the cases related to CL), and in Brazil, autochthonous cases of CL have been reported in all states.…”

Steppe lemmings and Chinese hamsters as new potential animal models for the study of the leishmania subgenusMundinia(Kinetoplastida: Trypanosomatidae)

“…Chinese hamsters and Steppe lemmings were used as these animals have been shown to be more susceptible to L. donovani than Golden hamsters, the most common rodent model for visceral leishmaniasis: In experiments where the three rodent species were directly compared after intradermal inoculation of L. donovani , both Chinese hamsters and Steppe lemmings showed more extensive spread of parasites over the body and higher parasite loads and infectiousness to sand flies then Golden hamsters. In addition, both Chinese hamsters and Steppe lemmings were also highly susceptible to cutaneous L. major (31). We inoculated culture-derived parasites intradermally into rodent pinnae to simulate the natural mode of infection to the best of our knowledge.…”