Figure 4.

Effect of concomitant use of methotrexate (MTX) and anti-interleukin-6 receptor (IL-6R) antibody on arthritis score. MTX (10 mg/kg) was administered 3 times a week from the first day of immunization. Rat anti-mouse IL-6R monoclonal antibody (MR16-1) (4 mg/mouse) was injected on day 10. (A) Arthritis score was assessed as described in the Methods section. Each symbol indicates the mean and standard error (SE) of 8 to 9 animals. Statistical significance was analyzed by Wilcoxon's test (P < 0.05, *vs. vehicle; #vs. MTX). Levels of (B) IL-6 and (C) serum amyloid A (SAA) were measured by ELISA. Sera were obtained on day 15. Each bar and error bar indicates the mean and SE of 8 to 9 animals. Statistical significance was analyzed by Dunnett's multiple comparison test (#P < 0.05) or the unpaired t-test (*P < 0.05).