Modulatory effects of vitamin D on peripheral cellular immunity in patients with recurrent miscarriage.

Problem We aimed to investigate the modulatory effects of vitamin D on peripheral blood cellular immune response in patients with recurrent miscarriage ( RM). Method of study The effect of vitamin D on the number of peripheral blood cells, T helper 1 (Th1) cytokines, and NK cytotoxicity was measured in 99 women with RM. Results The percentage of CD19⁺ B cells and NK cytotoxicity at an effector-to-target cell (E:T) ratio of 50:1, 25:1, and 12.5:1 were significantly higher in the vitamin D insufficiency group ( VDI) than in the vitamin D normal group ( VDN) ( P<.05 each). The proportion of TNF-α-expressing Th cells was significantly higher in the vitamin D deficiency group ( VDD) than in VDN ( P<.05). However, there were no significant differences between VDI and VDD. This dysregulation was significantly reduced with 1,25( OH)₂D supplementation. Conclusion The data suggest that the abnormalities of cellular immune response were observed in RM patients with a low vitamin D level, which could be regulated to some extent with 1,25( OH)₂D supplementation. [ABSTRACT FROM AUTHOR]