Mucins obtained from patients with enterocutaneous urinary diversions

Abstract

The ureteroenterocutaneostomy is a surgical procedure for urinary diversion by which an intestinal segment is used as a conduit or a reservoir for urine. Histological studies on colonic segments have shown a well preserved mucosal surface with numerous goblet cells and urine from these patients contains a mucus-like sediment. The present study demonstrates that such gels are composed of mucins occurring predominantly as a glycoprotein complex which is ‘insoluble’ in 6 m guanidinium chloride. The complex was brought into solution by reduction of disulphide bonds and the fragments (subunits) obtained behaved as typical mucins when subjected to density-gradient centrifugation in CsCl/4 m guanidinium chloride. High-M_r glycopeptides obtained after trypsin digestion of subunits expressed the ABH and Lewis antigens, in accordance with the patients' blood-group phenotype and with the regional distribution known from previous immunohistochemical studies on normal colonic mucosa. A heterogeneous population of mucin glycopeptides was revealed by using high-performance ion-exchange chromatography and the major carbohydrate-containing peak did not coincide with that expressing the blood-group activity.

Key Words:

• blood-group antigen
• colonic mucin
• tumour marker