Collagen Antibody-Induced Arthritis: A Disease-Relevant Model for Studies of Persistent Joint Pain

Rheumatoid arthritis (RA) is a complex autoimmune disease, with a prevalence of approximately 1% in the population worldwide. RA is a chronic inflammatory disease primarily affecting joints and patients suffer from a plethora of symptoms, including pain, fatigue and stiffness. Joint pain is one of the most egregious symptoms in RA. Animal models of RA are used extensively in research to understand the pathogenesis of inflammatory arthritis and in the assessment of potential disease-modifying agents. There is an increasing need for disease-relevant animal models for pain research and several of the RA animal models that previously were not used in pain research have now been characterized for this purpose. The most commonly used RA model is the collagen-induced arthritis (CIA) model. However, it has certain disadvantages when used for pain research. Here we describe an alternative model, the collagen antibody-induced arthritis (CAIA) model to study RA-induced pain. This model has been used to investigate disease pathology for more than 10 years, but has just recently been characterized as a pain model. In comparison to CIA, more mouse strains are susceptible to CAIA and the degree of joint pathology and systemic disease is less severe, making the assessment of arthritis-associated nociceptive behavior, such as paw withdrawal from mechanical or thermal stimuli, as well as changes in normal behavior such as locomotion more easily investigated. The aim of this chapter is to describe the CAIA model and several techniques used to study inflammatory pain-like behavior.