Airway epithelial cell wound repair mediated by alpha-dystroglycan

Dystroglycans (DGs) bind laminin matrix proteins in skeletal and cardiac mu scle and are expressed in other nonmuscle tissues. However, their expressio n in airway epithelial cells has not been demonstrated. We examined express ion of DGs in the human airway epithelial cell line 1HAEo(-), and in human primary airway epithelial cells. Expression of the common gene for alpha- a nd beta -DG was demonstrated by reverse transcriptase/ polymerase chain rea ction in 1HAEo(-) cells. Protein expression of beta -DG was demonstrated by both Western blot and flow cytometry in cultured cells. Localization of al pha -DG, using both a monoclonal antibody and the alpha -DG binding lectin wheatgerm agglutinin (WGA), was to the cell membrane and nucleus. We then e xamined the function of DGs in modulating wound repair over laminin matrix. Blocking alpha -DG binding to laminin in 1HAEo(-) monolayers using either glycosyaminoglycans or WCA attenuated cell migration and spreading after me chanical injury. alpha -DG was not expressed in epithelial cells at the wou nd edge immediately after wound creation, but localized to the cell membran e in these cells within 12 h of injury. These data demonstrate the presence of DGs in airway epithelium. alpha -DG is dynamically expressed and serves as a lectin to bind laminin during airway epithelial cell repair.