A Technique to Generate an Adjuvant-Induced Arthritis Mouse Model

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.

1. Induction of the adjuvant-induced arthritis (AA) mouse model

1. Suspend complete Freund's adjuvant (CFA) by vortexing at least 5 s, then draw 100 µL of suspension into an insulin injector.
   NOTE: We recommend using a completely new CFA in experiments to ensure sterility.
2. Anesthetize mice as described.
3. Mark the chosen paw and inject 20 µL of CFA into the ankle joint space. Inject 20 µL of suspension into four periarticular spots on the chosen paw (80 µL in total).
4. Remove mice from the breathing unit and put the processed mice in a new chamber. Monitor mice to ensure that they are breathing until they regain the ability to move.
5. Every 3 days, assess the joint diameter by measuring the ankle joint diameter using a pocket thickness gauge (Figure 1A).
6. Every 3 days, assess arthritis severity by arthritis scoring criterion (Figure 1C): 0, normal, no evidence of erythema and swelling; 1, the mildest arthritis, erythema and mild swelling confined to the tarsals or ankle joint; 2, moderate arthritis, erythema and mild swelling extending from the ankle to the tarsals; 3, severe arthritis, erythema and moderate swelling extending from the ankle to metatarsal joints; 4, the most severe arthritis, erythema, and severe swelling encompass the ankle, foot, and digits, or ankylosis of the limb.