The Mouse Collagen Antibody-Induced Arthritis (CAIA) model is a 21-day model bypassing the development of anti-collagen antibodies. Disease is induced using a cocktail of monoclonal antibodies directed against type II collagen.
Mouse CAIA Swelling vs. Time
Mouse CAIA Total Clinical Score vs. Time
Mouse CAIA Total Disease Burden
Collagen antibody-induced arthritis (CAIA) is a model of human rheumatoid arthritis. This model has the advantage of inducing disease in many strains of mice that are resistant to the traditional collagen-induced arthritis methods. Collagen antibody-induced arthritis relies on the injection of a cocktail of monoclonal antibodies directed against type II collagen (C-II), followed by a single injection of LPS. In animals, a significant part of the inflammatory attack on the joints is mediated by pathogenic antibodies directed against C-II. An advantage of this model is that compound assessment can be completed in a relatively short period of time. In standard collagen-induced arthritis protocols, disease doesn’t begin to appear until 3 – 4 weeks and a typical study might last 6 – 8 weeks. In collagen antibody-induced arthritis, the disease appears within 7- 8 days and studies can be completed within 18 days. An additional 7 days can be added to assess the effects of agents on the resolution phase of the disease. Collagen antibody-induced arthritis is dependent on IL-1β and TNF-α, but is independent of the effects of IL-6. The model is quite robust and produces disease in virtually 100% of the injected animals.
Injected animals develop rapid and severe arthritis within 2 – 3 days following LPS injection. Swelling develops in all limbs (hind and fore paws). Published literature suggests that histologic changes can be observed in the joints after 18 days on study.
Disease activity is assessed by measuring inflammation swelling in the affected joints (paw volume or thickness) over time. Treatments can be assessed in either prophylactic or therapeutic testing paradigms.Clinical scoring is accomplished by awarding a score of 1 for each swollen digit, a score of 5 for a swollen footpad, and a score of 5 for a swollen wrist or ankle. These are added together to give a maximal score of 60 for each animal.
For additional information our Mouse Collagen Antibody-Induced Arthritis (CAIA) model, please contact us at 1.877.CRIVER.1 or askcharlesriver@crl.com.