Poor effect of glutamin and human-EGF on autologic-allotopic transplanted ileum mucosa

After establishing a new method of autologic-allotopic ileum mucosa transplantation as a therapy for short-bowel syndrome, the effects of glutamine and human epithelial growth factor (human EGF) on the transplanted ileum mucosa were evaluated.

Ileum mucosa was transplanted in 28 young beagle dogs in a demucosed vascularised transverse colon segment. The ileum mucosa was kept in place with silicone stents in all animals. Eight animals of the control group were irrigated with saline solution. In the second group with 10 animals, 100 mg/kg glutamine were administered daily in the lumen. The 10 animals of the third group were treated with 25 microg/kg human EGF per day subcutaneously and irrigated with saline solution. 4 weeks later, histological specimens were harvested from the colon coat-ileum mucosa complex, the normal ileum and normal colon. Lumen diameter, percentage ileum mucosa uptake as well as mucosa and colon muscle coat thickness were evaluated.

In all groups, the diameter of the lumen was larger than 10 mm after fixation, due to the silicone stent. The group with glutamine irrigation showed the largest lumen diameter. A complete mucosa lining of the inner surface of the colon muscle coat was achieved in none of the animals. The highest percentage of ileum mucosa uptake was found in the group with glutamine irrigation. In most animals, the transplanted ileum mucosa was markedly thinner than normal ileum mucosa. Only in the group with glutamine irrigation did we find two animals with nearly normal mucosa thickness. The longitudinal muscle of the transplanted colon coat was thicker in all three groups compared to normal colon. There were no differences in thickness of the circular muscle in all animals compared to normal colon.

Silicone stents maintain a lumen after autologic-allotopic ileum mucosa transplantation. However, additional irrigation with glutamine, as well as treatment with human EGF subcutaneously could not provide a complete lining of the colon muscle coat with transplanted ileum mucosa. A modification of the operative procedure is necessary to achieve a colon muscle coat that is completely lined with ileum mucosa before the absorptive capacity of the transplanted colon coat-ileum mucosa complex can be evaluated.