Relationship between vitamin D plasma level and Foxp3 gene expression among rheumatoid arthritis patients

Background and Aim: Rheumatoid arthritis (RA) is an autoimmune disease. It seems that the function of regulatory T cells (Tregs) is compromised in RA. Foxp3 is a critical transcription factor of these cells. The aim of this study was to determine the relationship of vitamin D plasma level with Foxp3 gene expression in the patients with RA. \nMaterial and Methods: 18 untreated RA patients and 41 healthy people participated in this study. Plasma levels of vitamin D were measured by competitive ELISA method. Foxp3 gene expression was also determined by using realtime PCR technique. \nResults: The expression of Foxp3 gene was significantly lower in RA patients compared to that in the healthy controls (p<0.001) .There was no significant relationship between vitamin D plasma levels with the rate of Foxp3 gene expression. \nConclusion: We found low levels of vitamin D could not affect the expression of Foxp3 gene. It seems that vitamin D deficiency cannot be considered as an effective environmental factor in the pathogenesis of RA.