Evaluating Immunomodulatory Effects of vitamin D on FOXP3 and RORγt Expression in Peripheral Blood Mononuclear Cells of Patients with Allergic Asthma

Purpose: This study was conducted to determine the direct effect of vitamin D (vit-D) on mononuclear cells of the blood, mainly T-lymphocytes, in allergic asthma and healthy subjects. Materials and methods: Isolated peripheral blood mononuclear cells from patients and healthy people were cultured 24-hours in 4 groups of treated with vit-D at 10-7 M, 10-6 M concentrations, dexamethasone, and control. After extraction of RNA, their cDNA was used for evaluating Foxp3 and RORγt genes expression by Real-time PCR technique. Results: There was a significant difference between the control group and the asthma group in terms of FOXP3 expression (P = 0.019). The treatment with dexamethasone significantly increased the expression of FOXP3 gene of the patient with no treatment (P = 0.023) and treatment with vit-D 10-7 M significantly reduced the FOXP3 gene expression in the same group (P = 0.027). There was no significant difference in RORγt gene expression between case and control groups (P = 0.805). All treatments significantly reduced RORγt gene expression in both case and control groups (P < 0.001). Conclusion: Vit-D decreased the expression of FOXP3 and RORγt genes. As RORγt gene increases the severity of the disease, then vit-D can improve the course of the disease.