text: Increased expression of cell surface IL-10R1 on RA CD4+ T cells
  The functional receptor complex of IL-10 consists of two subunits, the primary ligand-binding component IL-10R1 and the accessory component type 2 IL-10R [1]. IL-10R1 expression plays a critical role in cellular responses to IL-10 [29]. To examine whether the resistance to IL-10 inhibition in RA CD4+ T cells was due to limited receptor expression, the cell surface expression of IL-10R1 on PB CD4+ T cells from active RA patients and from healthy controls was determined by flow cytometric analysis. As shown in Fig. 3a,3b, the intensity of IL-10R1 expression on CD4+ T cells was significantly increased in RA patients compared with in healthy controls. These results suggest that the intracellular signal transduction pathway of IL-10 may be impaired in CD4+ T cells of active RA. 
  