PTX3 and rheumatoid arthritis: PTX3 was significantly higher in the serum of RA patients (n=119) in comparison with age- and gender-matched healthy donors (n=43), as expected in association with the inflammatory status of these patients (healthy donors median 1.25, IQR 0.76-1.64; RA median 3.23, IQR 2.28-4.99; Figure 1A).