Fig. 1

Ankle diameter measurements in rat CIA. Collagen type-II immunization of dark Agouti rats led to increased ankle diameter (mean ± SEM, n = 10 per group) by day 13, and these clinical parameters continued to worsen until reaching a plateau on days 18 through 20. The disease-induced increase in ankle diameter was generally dose-dependently attenuated by RCI (160 and 400 U/kg) versus the disease control group when administered after disease onset (beginning day 13). Treatment with ETN (10 mg/kg) also significantly decreased ankle diameter compared with the disease control. When administered in combination with ETN, 160 or 400 U/kg RCI further reduced ankle diameter vs ETN alone. Statistics were analyzed by 2-way ANOVA followed by a Newman-Keuls multiple comparisons test. All p values represent treatment compared with disease control. Abbreviations: ANOVA, analysis of variance; CIA, collagen-induced arthritis; ETN, etanercept; RCI, repository corticotropin injection; SEM, standard error of the mean