in contrast cocultures between urothelia and monolayers of 3t3 cells , applied to the surface of planar collagen substrata could only permit urothelial cell attachment but not growth or differentiation whereas lethally irradiated 3t3 ( feeder ) cells , under similar experimental conditions , could support the maintenance of an immature or incompletely differentiated urothelium .
C0227599
urothelial cell
C0227598
urothelium