Nucleic acid content and nuclear chromatin structure of human bladder cell culture lines as studied by flow...

Two human bladder cell lines, T-24 and HCV-29, are studied with flow cytofluorometry and acridine orange staining to determine relative DNA and RNA content per cell and to measure resistance to thermal denaturation of DNA in situ. The RNA/DNA ratio for HCV-29 is over twofold higher than that for T-24, a difference that is consistent with the differences in cytological morphology and staining characteristics of these two cell lines and is sufficient to distinguish them completely, although measurements of DNA or RNA alone may not. In addition, the two cell lines show differences in DNA "melting" curves that indicate structural or conformational differences in nuclear chromatin. It is evident that the features are related to nuclear and cellular morphology, and they may be of value as additional parameters for characterizing tissue culture cell lines.