An anti-mouse .alpha.9 integrin antibody, an anti-human .alpha.9 integrinantibody, a hybridoma cell producing any of the antibodies, a method ofproducing any of the antibodies and the hybridoma cell, and a pharmaceuticalcomposition comprising any of the antibodies are provided. The anti-.alpha.9integrin antibody exerts a therapeutic effect on cancer, for exampleproliferation and metastasis of a cancer cell, and an inflammatory disease,for example rheumatoid arthritis, osteoarthritis, hepatitis, bronchial asthma,fibrosis, diabetes, arteriosclerosis, multiple sclerosis, granuloma, aninflammatory bowel disease (ulcerative colitis and Crohn's disease), anautoimmune disease and the like by inhibiting the .alpha.9 integrin function.
