In the Collagen Antibody Induced Arthritis (CAIA) model, arthritis is stimulated through the administration of a cocktail of monoclonal antibodies that are directed to conserved auto-antigenic epitopes of collagen type II, followed by endotoxin challenge. 3-4 days after the initial disease induction step, the mice start developing pathology characterized by severe inflammation of all 4 mouse limbs. The incidence is 90-100% and symptoms persist up to several weeks after the induction.
Preclinical Efficacy evaluation
A C57Bl/6/CAIA study is normally completed in 2 weeks time. A standard protocol involves a therapeutic regimen with administration of therapeutics starting after the LPS boost, when pathology has already started developing.
Arthritis scoring in C57Bl/6 mice after CAIA induction and over a period of 14 days. Therapeutic regimen with Enbrel (30 mg/kg) and dexamethasone (2 mg/kg) significantly ameliorates arthritis symptoms.
• In-vivo arthritis score on daily basis, involving evaluation of the front and hind paw swelling
• Body weight measured and recorded tri-weekly
• Serum/plasma processed from blood obtained by cardiac puncture at the end of the study
• Histopathological evaluation of front and hind paw pathology after the end of the study (day 13)