Fig. 1
From: The role of vitamin D in autoimmune diseases: could sex make the difference?
Cross-talk between vitamin D and estrogen and vitamin D effects on immune response. Estrogen decreases the expression of CYP24A1, which is involved in the inactivation of vitamin D, and increases the expression of VDR gene. 1,25(OH)2D downregulates aromatase expression, decreasing estrogen level. 1,25(OH)2D also regulates immune cell subsets, interfering with antigen presentation and cytokine production