Correlation between the changes of regulatory T cells in peripheral blood and disease activity measures in rheumatoid arthritis / 中华风湿病学杂志

ABSTRACT

Objective:To investigate the level of regulatory T (Treg) cells of peripheral blood and evaluate the correlation between Treg cells and disease activity in rheumatoid arthritis (RA) to further clarify the role of Treg cells in the pathogenesis of RA.Methods:The participants included 300 patients with RA, from the Second Hospital of Shanxi Medical University between January 2016 and September 2018 and 100 gender and age matched healthy individuals. The absolute numbers and proportion of Treg cells and helper T (Th) 17 cells and the ratio of Th17/Treg in peripheral blood of these individuals were detected by flow cytometry combined with standard absolute counting beads. Main statistical analysis methods were t test, spearman correlation and rank sum test. Results:Patients with RA had lower absolute numbers [(35±13) cells/μl vs (26±17) cells/μl, t=4.815, P<0.01] and percentage [(5.1±1.5)% vs (4.4±2.0)%, t=4.111, P<0.01] of Treg cells compared with those in healthy controls, while the number ( t=1.114, P=0.266) and proportion ( t=1.577, P=0.116) of Th17 cells were not significantly changed. RA patients, regardless of new onset (no prior treatment) or treatment with immunosuppressants, had significantly lower absolute numbers of Treg cells [healthy controls (35±13) cells/μl; the Treg cells in new onset patients was (31±17) cells/μl, t=1.974, P=0.049; Treg cells in treated patients was (24±16) cells/μl, t=5.978, P<0.01] but not Th17 cells than healthy controls. With the increase of disease activity score uses 28 joint counts (DAS28), the absolute counts of peripheral Treg cells trended to decrease [remission group (33±15) cells/μl, low activity group (31±17) cells/μl, moderate activity group (28±17) cells/μl, high activity group (24±16) cells/μl], and were negatively correlated with DAS28( r=-0.139, P=0.016) and erythrocyte sedimentation rate (ESR) ( r=-0.116, P=0.046). Conclusion:The absolute counts of peripheral Treg cells decreased significantly, which are associated directly with the pathogenesis of RA rather than high-dose glucocorticoids or immunosuppressive agents. Changes in circulating Treg cells number may play a prominent role in the disease process of RA, which provides clinical basis for evaluation of disease activity and exploration of new effective therapies.