Fig. 4.

CCL2 (#MJE00, R&D systems, 500 ng (5 μL) i.a.) or vehicle (5 μL of 0.1% BSA in PBS) injected intra-articularly into a naïve wild-type and b naïve Ccr2 null mice. Knee hyperalgesia was measured before injection, and 1, 2, 4, and 24 h after injection. n = 11 vehicle, n = 11 CCL2 for wild-type; n = 4 vehicle, n = 5 CCL2 for Ccr2 null mice. *p < 0.05, **p < 0.01 vs vehicle at the same time point. Repeated measures two-way ANOVA with Bonferroni’s multiple comparisons test to compare CCL2 to vehicle at each time point. Mean ± SEM