(A) Dose-dependent inhibition of arthritis development by MTX. K/BxN mice were treated weekly with MTX (1, 10, or 25mg/kg) or carrier alone p.o. starting at the age of 3wk and followed for arthritis development. The graphs show mean ankle thickness ± SEM for n=8 mice per treatment group pooled from two independent experiments. (B,C) Co-therapy with MTX + 1MT. K/BxN mice were treated with Carrier, MTX alone (1mg/kg), 1MT alone (400mg/kg), or MTX + 1MT starting (B) before (age 3wk) or (C) after arthritis onset (age 4.5wk) and followed for the progression of arthritis. Arrows indicate the start of treatment. The graphs show mean ankle thickness ± SEM for n=9 mice per treatment group pooled from two independent experiments. *p<0.05, n.s., not significant.