Uroplakin II is a 15 kDa protein component of urothelial plaques. Studies have shown Uroplakin II mRNA was highly specific and was expressed in both bladder cancer tissues and peripheral blood of patients with primary and metastatic urothelial carcinoma of the bladder. Uroplakin II antibody [BC21] has exhibited an increased sensitivity (46/59, 78%) when compared to Uroplakin III [AU1] (191/56, 34%) in cases of urothelial carcinoma of the bladder with the exception of bladder and ureter, staining was highly specific in various normal and neoplastic tissues in an in-house study. Uroplakin II antibody [BC21] is a highly specific antibody that may be useful in identifying tumors of urothelial origin. PATENT PENDING.