• Korean Journal of Veterinary Research
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• v.41 no.2
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• pp.211-218
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• 2001

The $M_r$ 63,000 glycoprotein (GP63) and lipophosphoglycan (LPG) of Leishmania donovani were evaluated as vaccine candidates against visceral leishmaniasis. Mice were immunized with liposomeencapsulated GP63 and/or LPG that were purified from the soluble extract of L. donovani promastigotes, and were challenged with virulent amastigotes. Mice immunized with GP63/LPG in liposomes plus BCG resulted in a 27.4% reduction of amastigotes in the liver compared to the control group (liposomes plus BCG), and mice immunized with liposome-GP63 plus BCG failed to induce a protective immune response against the challenge infection. Immunization of mice with GP63 fused to the Schistosoma japonicum glutathione S-transferase (GP63-GST) plus BCG also failed to elicit protective immunity. To analyze the cause of failure to induce protection, cytokine release from the spleen cells of immunized mice and Leishmania-specific serum antibodies were analyzed. Spleen cells from mice immunized with GP63-GST plus BCG that were exposed to soluble extract of L. donovani in vitro produced 10-fold greater quantities of IFN-gamma and 3-fold greater quantities of IL-5 than cells from mice receiving BCG only or saline. Western blot analysis revealed that sera from these mice had Leishmania-specific antibodies recognizing 1 to 3 antigens of L. donovani with M. W. of 60-65 kDa. Although immunization of mice with GP63-GST induced a strong Th1 response, this study indicated that GP63-GST simultaneously elicited the Th2 response of the CD4+ T-cell, which was known to abrogate the protective immune response conferred by the Th1 effector function.

• Parasites, Hosts and Diseases
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• v.55 no.4
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• pp.367-374
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• 2017

Despite the broad distribution of leishmaniasis among Iranians and animals across the country, little is known about the genetic characteristics of the causative agents. Applying both HSP70 PCR-RFLP and sequence analyses, this study aimed to evaluate the genetic diversity and phylogenetic relationships among Leishmania spp. isolated from Iranian endemic foci and available reference strains. A total of 36 Leishmania isolates from almost all districts across the country were genetically analyzed for the HSP70 gene using both PCR-RFLP and sequence analysis. The original HSP70 gene sequences were aligned along with homologous Leishmania sequences retrieved from NCBI, and subjected to the phylogenetic analysis. Basic parameters of genetic diversity were also estimated. The HSP70 PCR-RFLP presented 3 different electrophoretic patterns, with no further intraspecific variation, corresponding to 3 Leishmania species available in the country, L. tropica, L. major, and L. infantum. Phylogenetic analyses presented 5 major clades, corresponding to 5 species complexes. Iranian lineages, including L. major, L. tropica, and L. infantum, were distributed among 3 complexes L. major, L. tropica, and L. donovani. However, within the L. major and L. donovani species complexes, the HSP70 phylogeny was not able to distinguish clearly between the L. major and L. turanica isolates, and between the L. infantum, L. donovani, and L. chagasi isolates, respectively. Our results indicated that both HSP70 PCR-RFLP and sequence analyses are medically applicable tools for identification of Leishmania species in Iranian patients. However, the reduced genetic diversity of the target gene makes it inevitable that its phylogeny only resolves the major groups, namely, the species complexes.

• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.1-7
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• 2017

Cutaneous leishmaniasis (CL) caused by Leishmania donovani is an endemic vector-borne disease in Sri Lanka. Over 2,500 cases have been reported since 2000 and the number of CL cases has dramatically increased annually. Total 57 clinically suspected CL patients attending the dermatology clinic in Anuradhapura Teaching Hospital were recruited from January to June 2015. Slit skin smears and skin biopsies were taken from each of the subjects. Clinical and epidemiological data were obtained using interviewer administered questionnaire. Forty-three (75.4%) patients among 57 were confirmed positive for L. donovani. The majority (77%) of infected patients was males, and the most affected age group was 21-40 years. Soldiers in security forces, farmers, and housewives were identified as high risk groups. The presence of scrub jungles around the residence or places of occupation (P=0.003), the presence of sandflies (P=0.021), and working outsides more than 6 hr per day (P=0.001) were significantly associated with CL. The number of lesions ranged from 1-3, and the majority (76%) of the patients had a single lesion. Upper and lower extremities were the prominent places of lesions, while the wet type of lesions were more prevalent in females (P=0.022). A nodular-ulcerative type lesion was common in both sexes. The presence of sandflies, scrub jungles, and outdoor activities contributed to spread of Leishmania parasites in an endemic pattern. Implementation of vector control programs together with health education with regard to transmission and prevention of CL are necessary to control the spread of this infection.