Effects of 1,25(OH)₂D₃ in immune response regulation of systemic lupus erithematosus (SLE) patient with hypovitamin D

Vitamin D deficiency has been associated with pathogenesis of autoimmune diseases including SLE; however, there were still lack of data about the effects of administration of vitamin D in immune regulation in SLE patients. The aim of this study was to investigate the effects of calcitriol/1,25(OH)₂D₃ on dendritic cells maturation and Th17 and Treg cells activation in SLE patients with hypovitamin D. The monocytes and lymphocytes of five SLE patients with hypovitamin D were divided into 4 groups, P0 (0 nM/control), P1 (1 nM), P2 (10 nM), and P3 (100 nM) as cultured samples. Flowcytometry analysis was used to evaluate dendritic cell maturation (the percentage of CD40, CD86, and HLA-DR expression) and the amount of Th17 and Treg cells (the percentage of Th17 and Treg cells). Cytokines production of IL-12, IL-17A, and TGF-β measured by ELISA. This study showed significant differences in CD40, CD86, HLA-DR expressions, and Th17 percentage in 10 nM of 1,25(OH)₂D₃ compared to that of control. For cytokines secretion, there was also significant difference between IL-12p70 and IL-17A levels in 10 nM of 1,25(OH)₂D₃ compared to that of control. The 1,25(OH)₂D₃ increased Treg cells and TGF-β level but not significant. Our study concluded that 1,25(OH)₂D₃ inhibited dendritic cells maturation and Th17 cells activation in SLE patients. The 1,25(OH)₂D₃ increased Treg cells but not significant.