Animal models of rheumatoid arthritis. Clues to etiology and treatment.

Animal models of rheumatoid arthritis (RA) provide useful systems for the characterization of the immunopathogenic mechanisms of chronic inflammatory synovitis. Although at least eight models have been described, the adjuvant arthritis, streptococcal cell wall-induced arthritis, and collagen-induced arthritis models have provided the most useful insights. Each of these three models has contributed clues to our understanding of RA and have yielded promising new approaches to treatment. These include combination pharmacotherapy, antigen-specific therapy, cell-specific therapy, and monoclonal antibody therapy. All of these immunotherapeutic interventions have been shown to be beneficial in one or more animal systems. This suggests that future therapies for RA and other human autoimmune diseases may be more immunoselective and, potentially, less toxic.