Surface Topography of the Healthy and Diseased Transitional Cell Epithelium of the Human Urinary Bladder

Abstract

51 biopsies from healthy and diseased epithelium from human urinary bladders were examined by scanning electron microscopy. The luminal surface of the cover cells was marked by microvilli and microplicae. The replacement of the cover cells takes place by simple desquamination. This exposes cover cells having numerous microvilli, and these later develop characteristic microplicae. The ability to form cover cells is lost by the transitional epithelium following tumour formation. No tumour-specific surface morphology was observed.

Ultrastructural Visualization of Concanavalin A Binding Receptor Sites in Neoplastic and Non-Neoplastic Transitional Cell Epithelium of the Human Urinary Bladder

“…These dark cells showed morphological signs of being disintegrated im mediately prior to desquamation (14). A similar cytoplasmic diffuse staining of mature, elderly cover cells has also been described after im pregnation with lanthanum (15), and therefore this is hardly Con A-specific.…”

“…Thus, the presence of Con A receptors in the plasma membranes of tumour cells is rather an unspecific cytomorphological expression of a defective property of such cells to differentiate from the basal layer to the surface, in agree ment with other surface characteristics (14). The fact that Con A stainability is a function of the degree of maturity also appears to be demonstrated by the observation that the intracytoplasmatic early stages of the plasma mem brane could be stained, while this capacity was lost in plasma membranes in the more highly differentiated intermediary and luminal cells.…”

Surface Topography of Deeper Cells Exposed by Ultrasonic Wave Forces in Neoplastic and Non-Neoplastic Epithelium of Human Urinary Bladder

“…The luminal surfaces of the mature superficial epithe lial cells in the mammalian urinary bladder exhibit reti cular microridges by SEM, and short uniform microvilli can be seen on the luminal surface of immature cells [1,5,6]. Since Arai et al [2], Jacobs et al [3] and Hicks and Wakefield [4] reported that these surface features of luminal cells changed in the neoplastic condition in duced by chemical carcinogens, the luminal surface to pography of these cells has been the focus of early mor phological changes of carcinogenesis in the urinary blad der.…”

“…Despite these descriptions of the topography of the luminal surfaces of these tissues, there have not been many reports describing the surface fea tures of the deeper cells in mammalian bladder tumors or bladder mucosa. SEM observations were only re ported on deeper cells which happened to be exposed in neoplastic [ 1 ] and non-neoplastic tissues [1,5,6], or were performed on these cells in tissue culture or organ cul ture [9,10], Martin and Wong [6] reported that the intermediate cells of the transitional epithelium in the guinea pig had short microvilli and cytoplasmic strands traversing the wide intercellular spaces as observed by SEM. They hap pened to observe the intermediate cells exposed under the superficial cells in 10-day-old guinea pigs in vivo, and ripple-like microridges could also be seen in their figures.…”

“…Pleomorphic microvilli have been accepted as topo graphic features of the luminal surface of superficial cells in human urinary bladder tumors [1] as well as in animal bladder tumors induced by chemical carcinogens [2][3][4], In contrast, reticular microridges have been reported as characteristic features of the luminal surface of superfi cial cells in the normal transitional epithelium of hu mans [1,5] and other mammalian urinary bladders [6]. Using scanning electron microscopy (SEM), all of these observations have focused on the luminal surface of the superficial cells lining the neoplastic or non-neoplastic epithelium of the urinary bladder.…”