Fujita Y, Asano T, Matsuoka N, et al. - This study was sought to define circulating Gal-9 in patients with rheumatoid arthritis (RA) and its relationship with RA disease activity and phenotype. Researchers recruited a sum of 116 RA patients and 31 age-matched healthy controls. They ascertained disease activity of RA patients by Disease Activity Score of 28 joint scoring system (DAS28-ESR). Via enzyme-linked immunosorbent assay, levels of Gal-9 in serum were determined. This study found increased serum levels of Gal-9 in RA patients and correlated with RA disease activity in RA patients without high titers of anti-CCP antibody (ACPA). The values of circulating Gal-9 may be affected by the levels of ACPA titers in RA patients with various clinical phenotypes. The finding imply that Gal-9 possessed the properties of pro-inflammatory or arthropathic biomarker under the status of ACPA titers.