Characteristics of an established cell line (KU-2) derived from human renal cell carcinoma: I. Cloning of cells and morphological study of clones; II. Cell kinetics of KU-2 cells; III. Detection of type C virus in the culture.

A KU-2 cell line derived from human renal cell carcinoma was established by an indirect culture system using the nude mouse in November, 1976. These cells have been examined from different points of view including light and electron microscopic observation, and chromosomal analysis. Histopathological characteristics of the KU-2 cell line, even after being transplanted back to nude mouse, remain similar. However, the characterization of this established cell line has not been fully elucidated. In the present experiments, attempts have been made to study the cloning of KU-2 cells and morphological feature of clones, cell growth and kinetics, and detection of the type C virus in the culture. These results suggested that the KU-2 cell line was not homogeneous but composed of a heterogeneous population of cells based on morphological difference of 6 clones and discrepancy between population doubling time and generation time when calculated from the growth curve and synchronous culture of the KU-2 cells, which may be explained by the cytotoxic effect of excess thymidine. Also the type C virus was negative in the medium.