MRC1 and rheumatoid arthritis: The high concentration of CTLA4-Ig upregulated the gene expression of CD204 and CD206 after both 3 and 12 h of treatment and that of CD163 only after 12 h of treatment compared to unstimulated RA-MDMs (CD204 and CD206: p < 0.05 at both 3 and 12 h; CD163: p < 0.05 at 12 h; Fig 3B).