CD68 and rheumatoid arthritis: Finally, IL-6 plasma levels directly correlated with the IHC score of sublining CD68+ cells in ST of RA in stable clinical and ultrasound remission (R = 0.43; p = 0.04) with a higher significance considering RA in sustained remission with BMI ≥ 25 kg/m2 (R = 0.66; p = 0.01) (Fig. 4M).