We propose to develop hybridoma derived monoclonal antibodies to human and animal transitional cell carcinoma (TCC). Fresh and frozen tumor would be used as immunogens. A semi-automated ELISA technique would be used for initially selecting hybridomas which produce antibodies of interest. The specificity of those antibodies selected after the initial screening would be further defined using indirect immunofluorescence and immunoperoxidase binding and direct binding of (35S)methionine or (75Se) selino-methionine radiolabeled hybridoma product. These tests would be performed against a large assortment of tumor and normal tissue which has been collected, catalogued and stored in a tissue bank of our laboratory over the last seven years. Antibodies of satisfactory specificity and affinity would be evaluated for their use in 1) scintigraphic imaging of primary and metastatic tumor, 2) the detection of tumor antigen in body fluids, 3) purification of tumor antigens, and 4) investigation of antibody-primed ADCC in vitro. The use of specific anti-TCC antibodies as vehicles for delivery of poisons or radiation for TCC treatment would be investigated if initial goals were met.