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Background: The great gerbil (Rhombomys opimus), is widely distributed in Asia and is a natural reservoir for zoonotic cutaneous leishmaniasis in many endemic areas, as well as Iran. Materials and Methods: In this study, infection to Leishmania species was investigated by two methods, parasitological and molecular survey, in the small number of R. opimus collected from Jovain, a Zoonotic Cutaneous Leishmaniasis (ZCL) focus located in North East of Iran. Results: Parasitological observation showed infection in only one of five rodents. But, ITS2-Nested-PCR revealed Leishmania infection in three out of 5 gerbils, including the parasitological positive one. Based on the PCR amplified size, two cases of infections were Leishmania major and one Leishmania turanica, their sequences are accessible in GenBank. The results of sequence analysis were consistent with the results obtained based on the size of the PCR. Conclusion: These findings re-confirm the important role of R. opimus in the natural circulation of Leishmania spp and indicate the need to be concerned about the disease in the study area. [ABSTRACT FROM AUTHOR]

BACKGROUND፡ Leishmaniasis is a vector-borne disease caused by an intracellular protozoan parasite called Leishmania spp. Different species produce different clinical outcomes; the majority of cases are cutaneous forms. Leishmania major is one of the main causative agents of cutaneous leishmaniasis (CL). Various methods are being using to diagnose CL, including microscopic examination, culture, and molecular detection of the parasite genome. METHOD: In the current study, we tried to compare three common molecular markers, including Kinetoplast DNA (kDNA), Cytochrome b (Cyt b), and Internal transcribed space 1 (ITS1), for the detection of Leishmania major. After cultivation of standard strain of L. major MHOM/IR/75/ER in RPMI 1640, certain number of promastigotes was subjected to DNA extraction and different PCR reactions. RESULTS: The lowest number of the parasite (5 promastigotes) can be detected by kDNA-PCR, followed by Cyt b-PCR (10 promastigotes), and ITS1-PCR (50 promastigotes). CONCLUSION: In conclusion, kDNA-PCR was the most sensitive marker and may provide more reliable data in the initial screening, especially in false-negative results provided by parasitological methods due to the low number of parasites. [ABSTRACT FROM AUTHOR]

Leishmania major (L. major) applies several mechanisms to escape the immune system. Interleukin-10 (IL-10) and Transforming Growth Factor (TGF-β) downregulate nitric oxide synthase (iNOS) leading to the survival of Leishmania within macrophages. The miRNAs are known as the modulators of the immune system. The present study was conducted to assess the effect of synthetic miR-340 mimic on cytokines (IL-10 and TGF-β1) involved in L. major infected macrophages. The miRNAs targeting of IL-10 and TGF-β1 was predicted using bioinformatic tools. Relative expression of predicted miRNA, IL-10 , and TGF-β1 was measured by RT-qPCR before and after synthetic miRNA mimic transfection. Concentration of IL-10 and TGF-β was measured in posttreatment condition using ELISA method. Also, infectivity was assessed by Giemsa staining. mmu-miR-340 received the highest score for targeting cytokines. The expression of miR-340 was downregulated in L. major infected macrophages. By contrast, expression of IL-10 and TGF-β1 was upregulated in infected macrophages. After miRNA transfection, TGF-β1 and IL-10 were both downregulated and interestingly, the combination of miR-340 and miR-27a had a stronger effect on the downregulation of target genes. This research revealed that transfection of infected macrophages with miR-340 alone or in combination with miR-27a mimic can reduce macrophage infectivity and might be introduced as a novel therapeutic agent for cutaneous leishmaniasis. • Evaluation of the effect of miR-340 mimic on IL-10 and TGF-β1 in L. major infected macrophages • Downregulation of miR-340 was observed in L. major infected macrophages • Upregulation of IL-10 and TGF-β1 genes was detected in L. major infected macrophages • After miRNA mimic transfection, the combination of miR-340 and miR-27a had more effect on IL-10 and TGF-β1 downregulation [ABSTRACT FROM AUTHOR]