Collagen-induced arthritis (CIA) is a model of chronic inflammatory arthritis which closely resembles human rheumatoid arthritis (RA). Since CIA shares similar immunological and pathological features with RA, this makes it an ideal model for screening therapeutics. This model also has the primary advantage that the mechanisms of pathogenesis are known; susceptible mice, rats or monkey develop arthritis after immunization with heterologous, native type II collagen. For mice, collagen is emulsified with complete Freund's adjuvant which is injected s.c. at the base of the tail. The onset of arthritis occurs within 4 to 5 weeks. For rats, collagen is emulsified in incomplete Freund's adjuvant (since rats are susceptible to adjuvant arthritis) and the onset of arthritis occurs within 10 days to 3 weeks, depending upon the strain of rat used. Clinical signs of arthritis include red and swollen paws. Histopathological features include infiltration of inflammatory cells, pannus formation and cartilage and bone destruction.
Rats are immunized and boosted with native chicken type II collagen. Spleen cells are harvested 2 weeks after the boost.