FGL1 and arthritic joint disease: In order to evaluate the therapeutic potential of Fgl1 for RA, we established a collagen-induced arthritis (CIA) model using DBA/1J mice (Figure 3A) and administrated normal saline or different concentrations of Fgl1 recombinant protein (10 or 50 μg/kg) at day 24, at which time point arthritis had already begun (arthritis score exceeded 1).