Distinct strains of Leishmania major induce different cytokine mRNA expression in draining lymph node of BALB/c mice

Abstract

Four genotypically distinct strains of L. major collected from persons residing in different endemic areas of cutaneous leishmaniasis in Iran were evaluated in BALB/c mice. Parasite virulence was evaluated by measuring the parasite burden in the lymph nodes. Immunogenicity of the strains was assessed by analysis of cytokines mRNA expression levels in popliteal lymph nodes of the mice in early (3, 16, 40 h) and late (week 1, W3, W5 and W8) time periods after infection. The expression of cytokines mRNA, namely Ifng, Il2,Il4,Il10 and Il12, was quantitated by real-time PCR. The lowest and the highest parasite loads were induced by Damghan (2·15 × 10⁷) and Shiraz (9·59 × 10⁹) strains, respectively. Moreover, Damghan strain elicited higher expression levels of Ifng and Il2 mRNA and the highest ratio of Ifng/Il4 mRNA expression compared with the other strains at 40 h and 8 weeks post-infection. The results indicate that the inoculation of BALB/c mice with different strains induced high diversity in parasite burden and cytokines gene expression. Amongst the four strains, Damghan strain showed the lowest parasite load and the highest tendency to induce expression of Th1 cytokines gene and might be considered as a safe and immunogenic strain.

Leishmania major strains isolated from distinct endemic areas show diverse cytokine mRNA expression levels in C57BL/6 mice: Toward selecting an ideal strain for the vaccine studies

“…MRHO/IR/75/ER). The strains had been collected from lesions of patients with CL residing in 4 endemic areas of L. major, namely Kashan (KA1), Shiraz (SH25), Damghan (DA39) and Dehloran (DE5) as defined previously [17]. The species of the 4 isolates were characterized by isoenzyme electrophoresis and PCR assays, in comparison to the reference strain and all were identified as L. major.…”

“…RNA was extracted from popliteal LN cells of 5 mice per group in different time points (1, 3, 5 and 8 weeks post-infection) as previously described [17]. Briefly, total RNA was extracted using a NucleoSpin RNA II kit (Macherey-Nagel, Düren, Germany) according to the manufacturer's instructions and resuspended in DEPC (Diethylpyrocarbonate-treated water; CinaGen, Iran).…”

“…The species of the 4 isolates were characterized by isoenzyme electrophoresis and PCR assays, in comparison to the reference strain and all were identified as L. major. Genetic polymorphism of the isolates and confirmation of the species had been characterized by RAPD-PCR and SSCP, as described previously [16,17].…”

“…Our previous studies have shown that 4 different strains of L. major, isolated from different endemic areas of L. major, have the ability to induce distinct virulence and different patterns of cytokines production or mRNA expressions when inoculated to susceptible BALB/c mice [16,17]. In the present study, the same 4 strains were inoculated to the resistant C57BL/6 mice to investigate the lesion size and the level of parasite burden and the type of immune response in this experimental model which mimics the human infection in order to characterize the best strain to be used for vaccine studies.…”

Sex- and age-dependent expression of Pax7, Myf 5, MyoG, and Myostatin in yak skeletal muscles

“…Prime Script RT-reagent Kit with gDNA Eraser (Perfect Real Time) and SYBR Premix Ex Taq were purchased from Takara Biotechnology (Dalian, China) (Asadpour et al, 2013). Pax7, MyoG, Myf5, and MSTN primers were synthesized by Sangon Biotech (Sangon Biotech, Shanghai, China) (Kang et al, 2013).…”