Fig. 3

Radiographic observations of femurs, tibiae, knee joints, and ankle joints. a μCT was used to clarify the structural changes of bones. Arrowheads, erosion surface or site of the destruction of bones. OP3-4 appeared to inhibit the bone loss induced by collagen-induced arthritis (CIA). Scale bar represents 1 mm. b ROIs used for the quantitative measurements of mineralized tissue at knee joints by DXA. The square areas (2 × 2 mm) are the ROIs used for the DXA analyses. c BMD and d bone mineral content at the joint. The regions of interest shown in light gray for measuring the indices (f/g and i/j) to show the changes of e femur epiphysis and h knee joint, respectively. Data presented as mean ± SD (n = 6). **p <0.01 vs. Normal-vehicle; ^# p <0.05, ^## p <0.01 vs. CIA-vehicle. Normal-vehicle group, nonimmunized mice receiving vehicle (20 % DMSO); CIA-vehicle group, immunized mice receiving vehicle (20 % DMSO); CIA-9 mg OP3-4 group, immunized mice receiving 9 mg/kg/day OP3-4 peptide; CIA-18 mg OP3-4 group, immunized mice receiving 18 mg/kg/day OP3-4 peptide