We observed an increase of CXCR3 (p < 0.01) and CXCR5 (p = 0.05) (Figure 2J green and blue arcs and Supplementary Figure 3B) in the SFMC from RA patients, both of these key chemokine receptors are involved in monocyte and monocyte-derived cell recruitment and retention at the site of inflammation in RA (43, 44). Here, CXCR3 is linked to rheumatoid arthritis.