Decreased CD200R Expression on Monocyte-Derived Macrophages Correlates with Th17/Treg Imbalance and Disease Activity in Rheumatoid Arthritis Patients

In the 2014 study involving 35 rheumatoid arthritis (RA) patients and 17 healthy controls, researchers discovered that RA patients exhibited significantly lower CD200R1 expression on monocyte-derived macrophages (MDMs) compared to the controls. This reduced expression was negatively correlated with disease activity indicators such as the 28-joint disease activity score (DAS28), erythrocyte sedimentation rates (ESR), and C-reactive protein (CRP) levels. Furthermore, the study found an association between decreased CD200R1 expression and an imbalance between Th17 cells and regulatory T cells (Treg) in active RA patients, which was not observed with Th1 or Th2 cytokine responses. The findings suggest that the CD200/CD200R1 signaling pathway may play a role in the pathogenesis of RA and could be linked to disease severity.