Cell surface antigens of human bladder cancer defined by mouse monoclonal antibodies

Mouse monoclonal antibodies were obtained by immunization with cultured human bladder cancer or lysates of bladder papilloma. They identify 11 distinct antigenic systems as defined by serological analysis of cultured cells and studies of antigen distribution in normal and neoplastic tissues. The most restricted of these antigens, Om5, defines a subset of bladder tumors. Om5 is not detected in normal bladder urothelium or in any other normal or malignant tissue. T101 and JP165 are also subset markers for bladder cancer that are not detected in normal tissues. T16, T43, T87, and J143 (antigens represented on many cultured cells) are found in specific areas of the normal urinary tract and in a distinctive range of other normal and malignant cell types--e.g., T16 expression in pluristratified epithelium of skin, exocervix, and esophagus. T138 antigen is also a common feature of cultured cell lines, but its expression in sections of normal tissues is restricted to endothelial cells. In contrast, T110 is poorly represented on cultured cells but can be detected in culture supernatants. Localization of T110 in normal tissues showed that it is a component of the extracellular matrix. All determinants detected by this series of antibodies are heat labile and not related to A, B, H, I, Lewis blood group antigens. Six of the antibodies immunoprecipitated glycoproteins from radiolabeled cell lysates: AbT16 (Mrs 48,000 and 42,000), AbT87 (Mr 60,000), AbT43 (Mr 85,000), AbJ143 (Mr 140,000, 120,000, 60,000), AbT43 (Mr 85,000), AbJ143 (Mr 140,000, 120,000, and 30,000), and AbT110 (Mr 240,000).