Use of the ileal conduit as a model for studying human small intestinal mucus glycoprotein secretion.

To establish a human model system for investigating control of mucus secretion by the small intestine, we have studied the output of mucus glycoprotein in the urine of patients with ileal conduits. A highly specific enzyme-linked immunosorbent assay (ELISA) was used to measure mucus glycoprotein with a sensitivity down to 0.3 ng protein of mucus glycoprotein. The assay detects human ileal mucus glycoprotein in the urine of ileal conduit patients; for an individual subject, the amount hardly varied from day to day, although there were substantial differences between individuals in the amounts secreted. Control urine from persons with normal bladders did not contain any mucus glycoprotein that reacted in the ELISA. The model has many advantages over other experimental systems for studying the rate of mucus glycoprotein secretion from the human ileum and can also be used as a reproducible resource of undegraded mucus glycoprotein.