Collagen-Induced Arthritis Model in Mice

Chick collagen type II (CCII) (2 mg/mL; Chondrex, Inc., Redmond, WA, USA) was mixed with complete Freund’s adjuvant (CFA) (Chondrex, Inc) and injected intradermally on day 0 at the base of the tail of with 100 μL of an emulsion into 8- to 11-week-old DBA/1J mice. On day 21, mice received an intradermal booster injection with 100 μg of CCII in incomplete Freund’s adjuvant (IFA) (Chondrex, Inc). To investigate the treatment efficacy of IL13Rα1 at disease onset, Lv-mouse IL13Rα1 or its control Lv-Ctrl with GFP tag was injected into the knee joints of DAB/1J mice. The thickness of the knee joints was measured using Vernier calipers. The clinical arthritis score was calculated as described previously [24 (link)]. The maximum possible score per mouse was 12. Experiments were performed using 10 mice per group. Histological analysis of knee joints was fixed in 10% buffered formalin for 48 h and decalcified in 15% EDTA. The paws were then embedded in paraffin, and 5-μm sagittal serial sections of whole knee joints were cut. Tissue sections were stained with hematoxylin and eosin.