Figure 2

Paw Cytokines Follow Disease Progression in CAIA Mouse Model. Female DBA/1 mice were injected i.v. with anti-collagen type II antibodies and given a LPS booster injection three days after the antibody transfer. This combination of antibodies and adjuvant provides a potent and rapid, but self-limiting, antibody dependent arthritis. (A) Disease is established and mice enter the study when specific criteria are met (see materials and methods). Dexamethasone significantly reduced mean paw thickness (averaged from individually measured paws - front, back, right and left), *p < 0.01 versus vehicle control group, N = 10 per group. (B) Paw IL-1β concentration sampled in 3 mg of total protein prepared as described in the materials and methods. As expected from the paw swelling, dexamethasone reduces cytokine levels compared to the vehicle control group, *p < 0.05. (C) Paw IL-12 slowly increases overtime as disease progresses, dexamethasone treatment significantly reduces paw cytokine levels, *p < 0.05, N = 5 per group. (D) Histological analysis of paw swelling using H&E and Safranin-O stains (carpus shown). Vehicle shows leukocytic infiltrates, matrix degradation and osteolysis, dexamethasone treated mice compared to non-diseased animals (data not shown), N = 5 mice per group, representative images shown, 4× magnification. All graphs show Mean ± SEM.