PRTN3 and rheumatoid arthritis: In RA patients with low ACPA titers (<200 U/mL), circulating sTIM-3 was significantly higher in C reactive protein (CRP)-positive patients than it was in CRP-negative patients (2871 pg/mL, [IQR 2145–3921] vs 2081 pg/mL, [IQR 1714–2840], P = .007).