CXCL16 and rheumatoid arthritis: Pearson's r analysis showed a significant positive correlation of sCD14 with LBP (r = 0.669, P < 0.0001 in RA subjects and r = 0.521, P = 0.0001 in healthy controls), lysozyme (r = 0.708, P < 0.0001 in RA subjects and r = 0.480, P = 0.0005 in healthy controls), and CXCL16 (r = 0.618, P < 0.0001 in RA subjects and r = 0.759, P < 0.0001 in healthy controls) in both RA patients and in healthy controls (Figures 3A–C).