Collagen-induced arthritis (CIA) in mice is widely used as an experimental model for rheumatoid arthritis. Initial symptoms of inflammation in the CIA model occur at approximately day 21-24 with the model requiring 6-8 weeks to complete. The induction of the disease is typically at 80% of the animals and varies from laboratory to laboratory and with the use of different collagen sources. The disease symptoms also appear at slightly different times in different animals, making therapeutic administration protocols more demanding technically.