Background |
Trefoil Factor 3 (TFF3), also known as Intestinal Trefoil Factor (ITF) and P1. B, is one of threestructurally related secreted proteins that contain trefoil domains. These domains adopt a three-leaved conformation held together by conserved intrachain disulfide bonds. TFF3 is an approximately 7 kDa peptide that plays an important role in epithelial regeneration and wound healing. It can form disulfide-linked dimers or associate into disulfide-linked complexes with the intestinal mucous proteins FCGBP and MUC-2. TFF3 is expressed by epithelial goblet cells in the respiratory tract, biliary and breast ducts, conjunctiva, small and large intestine, and cardia of the stomach. Following secretion, TFF3 is retained in the overlying mucous layer and is also found in breast milk and serum. TFF3 is also expressed by chondrocytes during bone development and by select cochlear, hypothalamic, and pituitary neurons (16-18). Mature human TFF3 shares 76% amino acid sequence identity with mouse and rat TFF3.TFF3 is upregulated in response to a range of epithelial disruptions . In the gastrointestinal (GI) tract, it is upregulated in foci of intestinal metaplasia, hyperplastic polyps of the colon, stomach ulceration, and erosive gastro-esophageal reflux disease (GERD) . In some cases, it is also elevated in the serum following GI ulceration . TFF3 binds to oligosaccharide components of LPS derived from H. pylori, a bacterium associated with the development of gastric ulcers and cancer . It promotes epithelial wound healing by inducing the migration of biliary, bronchial, and intestinal epithelial cells .Mice lacking TFF3 show increased sensitivity to intestinal ulceration and impaired re-epithelialization of the wound. Lumenal administration of TFF3 in the intestines can accelerate wound healing and reduce the severity of colitis. |