New Validated Rheumatoid Arthritis Study Services Now Available
January 2, 2013 - Rheumatoid arthritis (RA) is a long-term disease that leads to inflammation of the joints and surrounding tissues. It is an autoimmune disease occurring in every ethnic group, affecting nearly 1% of the world’s population, yet its cause remains unknown.
Charles River offers several rat and mouse models of RA, including collagen-induced arthritis (CIA) and collagen antibody-induced arthritis (CAIA), two of the most requested assays in the RA field of study.
Collagen-induced arthritis shares a number of immunologic and pathologic features with human RA. The model relies on the induction of an immune response to heterologous type-II collagen (C-II) and has been developed in rats and mice. While the clinical course of the disease in animals differs from that in humans, the synovial inflammation as analyzed by histology and immunohistochemistry is quite similar to that found in active RA in humans. In CIA, it is possible to study specific interactions between autoantigens, T-cells, antigen-presenting cells and anti−C-II antibodies. CAIA differs in that the disease is replicated using commercially acquired antibodies which are administered to the animal. This leads to a robust, even model of disease which requires a shorter study time than CIA, as the immune system does not need to be induced.
At Charles River, the course of the disease is monitored by measuring the total volume of the hind paws using a water plethysmometer and recording clinical scores for all 4 paws. Clinical scores are objectively assigned using the Holmdahl scoring system. This system assigns a score of 1 for every red or swollen digit, 5 for a swollen footpad and 5 for a swollen wrist or ankle. The maximum score achievable is 15 per limb, or 60 per animal. Overall disease burden is estimated by integrating the area under the hind limb swelling vs. time curve. Disease suppression is determined by calculating the relative area under the curve (AUC) for each treated animal relative to the mean AUC of the vehicle-treated control group, as a percentage.
Charles River also offers full histopathology options for limbs sampled from rodents at the end of the study.
For more information on our RA models, please contact us at 1.877.CRIVER.1 or askcharlesriver@crl.com.
Related Information