بررسی اثر اینترلوکین-22 در افزایش ایمنی‌زایی DNA واکسن کد کننده ژن TSA لیشمانیا ماژور در موش BALB/c

Background and purpose: Previous Research shows the use of plasmids containing genes TSA to be useful as vaccines for Leishmania major. Recently, the role of interleukin-22 (IL-22) in tissue repair has been demonstrated. In this research, the effect of IL-22 on encoding TSA gene of Leishmania major in BALB/c mice was assessed. Materials and methods: pcDNA3 plasmid containing the gene encoding TSA protein (pcTSA) of Leishmania major, along with the cytokine IL-22 was used. 60 BALB/c mice were divided to 4 groups of 15. Control groups received pcDNA3 and PBS and a group was vaccinated intramuscularly with the TSA gene containing plasmid. Fourth group received plasmid containing the gene for the TSA and IL-22 protein. IL-4 and interferon gamma (IFN-γ) levels (MTT test) were used to evaluate the cellular immunity and IgG2a, IgG1 and Total IgG levels [enzyme-linked immunosorbent assay (ELISA) method] to evaluate the humoral immunity. Measuring the diameter of the lesions and the age and weight of the mice was performed. Results: The simultaneous use of plasmid containing the gene encoding protein TSA and IL-22 significantly increased the mean level of IFN-γ and reduced the mean level of IL-4 compared to the other groups. While the mortality rate at 27th week after intervention was 100 % in the control group, the surveillance rates of pcTSA and pcTSA + IL-22 groups were 80%. pcTSA + IL-22 group had the highest weight in 30th week. pcTSA + IL-22 group had significantly smaller lesions compared to control and pcTSA groups. Conclusion: Results show the efficacy of pcTSA + IL-22 in improving the vaccination of cutaneous leishmaniasis.