Trefoil factor family domain peptides in the human respiratory tract

Trefoil factor family domain peptides (TFF) are thought to be involved in m ucosal epithelial restitution and wound healing of the gastrointestinal tra ct and are up-regulated in ulceration and in a variety of solid tumours. It was hypothesized that TFFs are also expressed on mucosal surfaces of the h uman respiratory tract. Lung tissue, nasal polyps, and sputum samples from seven patients with cystic fibrosis (CF), two with chronic and acute bronch itis, and non-dysplastic material from two cases of bronchial adenocarcinom a were analysed for TFF expression by immunohistochemistry, immunofluoresce nce, western blot and RT-PCR. Expression of TFF1 and TFF3 was observed in m aterial from all patients. TFFs were localized in goblet and ciliated cells , as well as in some submucosal cells of tracheobronchial tissues and nasal polyps from normal and CF individuals. In sputa of patients with CF and wi th chronic or acute bronchitis, TFF1 and TFF3 were detected by western blot ting. Freshly cultivated nasal epithelial cells transcribed and secreted TF Fs and mucins, whereas nasal cells cultivated for 6 weeks still expressed m ucins, but not TFFs. Secreted TFFs and mucins also bound to the surface of Staphylococcus aureus in infected CF airways. In conclusion, TFF1 and TFF3 are expressed and secreted in normal and inflamed airways. The association of TFFs with bacteria may contribute to the anti-microbial mucociliary defe nce system. Copyright (C) 2000 John Wiley & Sons, Ltd.