Fig. 4

Experimental validation of amrinone in suppressing murine B-cell function and the pathogenesis of the CIA mouse model. Drug effect of the selected drugs and the positive control on in vitro murine (a) B-cell survival, (b) activation, (c) proliferation, and (d) immunoglobulin production. Colours represent the responses to diluent and different drug concentrations (low, medium, high); for specific concentrations, see Additional file 2: Table S2. Having successfully validated adapalene and amrinone in vitro, we conducted in vivo experiments for amrinone. Mice with collagen-induced arthritis (CIA) were treated with diluent (n = 5) or amrinone (30 mg/kg, n = 5) for 3 weeks. The (e) rear paw thickness, (f) clinical scores, and (g) collagen-specific serum autoantibodies were measured. Furthermore, drug efficacy was assessed by analysis of (h) joint immune cell infiltration using H&E staining and (i) bone erosion using Safranin-O staining. *P < 0.05, **P < 0.01, ***P < 0.001. Dimethyl furamate, DMF