Induction of collagen-induced arthritis
Native chicken CII was obtained from Sigma-Aldrich (St. Louis, MO). CII
was dissolved in 0.01 M acetic acid and emulsified in Complete Freund’s
Adjuvant (CFA). CFA was prepared by mixing 5 mg heat-killed
Mycobacterium tuberculosis (H37Ra; Difco Laboratories, Detroit, MI) and
1 mL Incomplete Freund’s Adjuvant (Sigma-Aldrich). Mice were immunized
intradermally at the base of the tail with 200 mg of CII in CFA on days
0 and 21. Arthritis was evaluated visually, and changes in each paw were
scored on a scale of 0 to 3 as follows; 0 = normal, 1 = slight swelling
and/or erythema, 2 = pronounced swelling, 3 = ankylosis. The score was
summed-up for each limb (maximum score = 12).