Urothelium-specific antibody and lectin surface mapping of bladder urothelium

Abstract

Coupled ligand-colloidal gold complexes were found to provide a convenient approach for the localization of scanning electron microscopy of cell surface membrane antigens and lectin-binding sites on bladder urothelium and for the immunocytochemical identification of urothelial cell populations at different stages of differentiation. The ligands used to prove the membrane were a urothelium-specific rabbit antibody raised to a urothelial membrane-associated antigen (UMA), and two lectins: Concanavalin A (Con A) and peanut agglutinin (PNA). A complex luminal surface distribution pattern was demonstrated by the UMA antigen related to the stage of urothelial cell maturation and differentiation. UMA could be detected on the surface of immature and early differentiating intermediate cells, but was absent from the late differentiation stage, becoming re-expressed as the cells matured and was found in greatest abundance on the terminally differentiated superficial cells. It was absent on cells in benign hyperplasia of the urothelium. Cellular and regional differences in lectin binding to the urothelial cell surface was suggested with Con A receptors localized uniformly over the superficial cells, and PNA receptors confined to linear arrays or occasional clusters over the apical surface but evenly dispersed over the lateral surface of these cells.

Immunohistochemical Analysis of the Human Bladder

“…In the urinary tract most attention has been addressed to the urothelial cell, and in particular to blood group antigens A, B and O(H) with changes of expression of these (as well as other blood group antigens) with neoplastic transformation (Bergman and Javadpour, 1978;Lange et al, 1978;Gunter et al, 1983;Rearden et al, 1983;Summers et af., 1983). Other epithelial cell antigens have been identified on urothelial cells including urothelial membraneassociated antigen (UMA) (Hodges et al, 1982), luminal epithelial antigen (LEA) (Nathrath et at., 1979) and epithelial membrane antigen (EMA) (Pocock et al, 1983). However, despite close scrutiny of urothelial cell antigen status, little attention has been paid to accompanying lymphocyte and macrophage populations.…”

Behavior of Epithelial Differentiation Antigens (Carcinoembryonic Antigen, Epithelial Membrane Antigen, Keratin and Cytokeratin) in Transitional Cell Carcinomas of the Bladder

“…Several investigators have reported a correlation be tween morphologic differentiation and expression of spe cific molecules both in normal and neoplastic urothelium [14][15][16]. Immunohistochemical markers have been useful in our study for a more exact typing of tumor grades and a better characterization of urothelial dysplasia and carci noma in situ.…”

Urinary System

“…Scanning electron microscopy has demonstrated a uniform distribution of concanavalin A-binding sites over the superficial cells of the normal urothelium, attributable to cell surface membrane glycoproteins (Hodges et al 1982). Studies using the avidin-biotin complex method resulted in a weakly positive staining with concanavalin A, showing a spotty membranous pattern (Takai et al 1987).…”