To test the potential of COMP for the induction of arthritis, we immunized B6N mice with COMP emulsified in complete Freund, adjuvant (CFA, #263810, Difco, BD) or in incomplete Freund’s adjuvant (IFA, #263910, Difco, BD) containing Mycobacterium Tuberculosis strain H37Ra (M.T., #231141, Difco, 0.5 mg/ml). The gene discussed is COMP; the disease is arthritic joint disease.