EGF and TGF-beta(1) gene expression in chronically rejecting small bowel transplants

Long-term survival of small bowel transplants is hampered by chronic reject ion. Epidermal growth factor (EGF) and transforming growth factor beta (TGF -beta P) have opposing, regulatory roles in normal intestinal physiology an d may be involved in the pathogenesis of chronic intestinal rejection. Our aim was to investigate the expression of EGF and TGF-beta(1) in chronically rejecting small bowel transplants. Orthotopic small bowel transplantation was performed in the allogeneic DA-to-AS rat combination; Cyclosporin was a dministered temporarily to prevent acute rejection. Controls were DA isogra fts and normal DA rats. PreproECF and TGF-beta(1) gene expression was evalu ated by northern blot analysis of the ileum RNA and standardized against gl yceraldehyde-3-phosphate-dehydrogenase expression. Allografts demonstrated functional impairment and histological features of chronic rejection, where as isografts appeared normal. Allografts demonstrated a significant reducti on of EGF mRNA when compared to DA isografts. No significant changes were d etected in TGF-beta(1) expression in either allogeneic or syngeneic grafts. In conclusion, this study demonstrates reduced preproEGF and preserved TGF -beta(1) gene expression in chronically rejecting small bowel transplants.