Background: Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints and other tissues and organs of the body. Previous reports have demonstrated the imbalance of T helper (Th) subsets and Treg activity in the development, progression, and remission of RA. Here, we investigated the mRNA expression of four major transcription factors T-bet (Th1), GATA (Th2), RORc (Th17), and Foxp3 (Treg) in peripheral blood of different groups of RA patients.
Materials and methods: In this case-control study, 60 patients with RA, including 20 newly diagnosed, 20 under treatment, and 20 in remission, as well as 20 patients with osteoarthritis, and 20 age- and the sex-matched healthy individual were enrolled. Diagnosis and classification of patients were done according to the American College of Rheumatology criteria. The relative mRNA expression of transcription factors, including T-bet, GATA, RORc, and Foxp3, was measured using qRT-PCR.
Results: The relative expression of T-bet in RA patients was significantly increased in healthy controls (P = 0.002), while the relative expression of Foxp3 in RA patients was significantly decreased in healthy controls (P < 0.0001). There was no significant difference in the expression of GATA3 or RORc among RA patients, healthy controls, and osteoarthritis group.
Conclusions: The results indicate the importance of Th1 and Treg cells in RA; however, the role of Th17 cells appear to be of little importance in these patients. It seems that Th2 cells do not interfere with RA development.