COMPARISON OF INTERLEUKIN-11 AND EPIDERMAL GROWTH-FACTOR ON RESIDUAL SMALL-INTESTINE AFTER MASSIVE SMALL-BOWEL RESECTION

Background/Purpose: Interleukin 11 (IL-11) is a multifunctional cytoki ne derived from bone marrow, which has a trophic effect on small bowel epithelium. This study compares the effects of IL-11 with epidermal g rowth factor (EGF), a growth factor known to enhance small bowel adapt ation. Methods: Forty Sprague-Dawley rats (90 to 100 g) underwent an 8 5% mid-small bowel resection with primary anastomosis on day 0. Rats w ere divided into four treatment groups: controls (group I) received bo vine serum albumin (BSA), group II received IL-11, 125 mu g/kg subcuta neously (SC) twice daily, group III received EGF, 0.10 mu g/g SC bid, and group IV received EGF and IL-11 in the above doses. Half of the an imals (five per group) were killed on day 4 of therapy, and the rest w ere killed on day 8. Animals were evaluated for weight, mucosal length , and bowel wall muscle thickness on days 4 and 8, and expression of p roliferating cell nuclear antigen (PCNA) in intestinal crypt and smoot h muscle cells on day 8. Results: There were two deaths; both were 8-d ay controls. Body weight was similar at day 4 and day 8. Mucosal thick ness in groups II (IL-11) and group IV (IL-11 and EGF) was significant ly increased at day 4 and 8 when compared with controls (group 1) and EGF (group III, P<.001). Muscle thickness was significantly increased in the EGF and combined group IV compared with the BSA controls and IL -11 groups (P <.001). Thirty-two percent of the mucosal crypt cells in Group I stained positive for PCNA, whereas 51%, 53%, and 60% stained positive in groups II (IL-11), III (EGF), and IV (IL-11 and EGF), resp ectively. In groups I and II, 2% and 1.7% of the myocytes stained posi tive for PCNA, whereas 11.2% and 5.2% of the myocytes in group III and IV stained positive. Conclusions: These data suggest that IL-11 has a trophic effect on small intestinal enterocytes, causing cell prolifer ation and increased mucosal thickness. EGF has a more generalized effe ct on intestine causing proliferation of both enterocytes and myocytes , IL-11, with or without EGF, may be a useful adjunct in instances of short bowel syndrome. Copyright (C) 1998 by W.B. Saunders Company.