Normal human urothelial cells in culture. Subculture procedure, flow cytometric and chromosomal analyses.

Epithelial cell cultures of urothelial origin can be initiated with the sediment of voided urines of normal adults. The proliferating cells can be subcultured provided that nonconfluent cultures are used. In some instances cells have been transferred up to seven times. Flow cytometric analysis of the cells grown in vitro revealed a DNA distribution pattern consistent with a nonsynchronized, proliferating diploid cell population. Karyologic studies showed that 98% of the cells were diploid and had normal banding patterns. Tetraploid cells with 92 chromosomes constituted about 2% of the counted metaphases. These observations, supplementing the authors' previous data provide further evidence that urothelial cells derived from normal adults retain characteristics of normal human cells. Urine represents an easily available source for initiating cultures of human epithelial cells and the application of the system in diagnosis and research is being explored.