Antigenic heterogeneity of long-term cultured renal carcinoma cell line (KU-2) analyzed by tumor specific monoclonal antibodies.

The antigenic heterogeneity of a long term cultured cell line has not been clearly demonstrated. In the present study, monoclonal antibodies (MoAbs) to an established cell line KU-2 derived from a human renal cell carcinoma were used to analyze antigenic variation of KU-2 and its subclones. Characterization of thus produced MoAbs was attempted by determining the binding ability to other established cell lines, by enzyme linked immunosorbent assay (ELISA) and immunohistochemical studies with indirect immunofluorescence technique to find cell surface antigens on KU-2. Five MoAbs (ARC-1, ARC-2, ARC-3, ARC-7, ARC-8) were obtained. With these MoAbs three different antigenic determinants were detected on KU-2. According to the degree of expression of these three antigenic determinants, the presence of antigenic variants of KU-2 subclones was demonstrated. Among these MoAbs, ARC-1 showed high specificity for KU-2, and the antigenic determinant detected by ARC-1 was proven to be shared by each KU-2 subclone.