UNME/K1: an IgG2a monoclonal antibody specific to cytokeratin of human urinary bladder squamous cell carcinoma.

The main distinctive feature of carcinoma in schistosomal bladder is keratinized squamous cell carcinoma. Keratins/cytokeratins constitute a multigeneic family of structurally related polypeptide markers for the malignant state of epithelial cells. A monoclonal antibody (UNME/K1) regognizing keratins associated with squamous cell carcinoma of the human urinary bladder was generated at the Urology and Nephrology Center, Mansoura, Egypt (UNME), by fusion of spleenocytes from a BALB/c mouse immunized with a keratin extract (K1) of human squamous cell carcinoma and P3X63Ag8/U1 syngeneic myeloma cells. UNME/K1 was purified by a protein-A affinity column and was of the IgG2a type, as determined by immunoelectrophoresis and gel diffusion techniques. When tested against keratins of different types of urinary bladder tumors using enzym linked immunosorbent assay (ELISA), UNME/K1 reacted only with the high molecular weight keratin of squamous cell carcinoma and showed selectivity towards specific histopathological grades of tumors.