Background & aims: Heparin-binding epidermal growth factor-like growth factor (HB-EGF) has been recently identified as a member of the EGF family. EGF receptors to which HB-EGF can bind have been detected in some types of gastric epithelial cells. The aim of this study was to investigate whether HB-EGF is produced in gastric epithelial cells to maintain normal gastric mucosa.
Methods: Gene expression and production of HB-EGF protein were investigated using Northern hybridization and immunohistochemistry, and the types of cells producing this protein were determined in human gastric mucosa.
Results: HB-EGF messenger RNA was detected in the body and antrum. Immunohistochemical staining showed that HB-EGF was localized mainly in parietal cells of fundic glands and in gastrin cells of pyloric glands. Also, the immunoreactivity of EGF receptors was observed in parietal cells and gastrin cells and faintly in surface epithelial cells and mucous neck cells of the proliferative zone.
Conclusions: The results suggest that HB-EGF is synthesized mainly in parietal cells and gastrin cells and may act in an autocrine and/or paracrine manner in the regulation of proliferation and differentiation of the gastric mucosal cells through their surface EGF receptors.