ABSTRACT
Objective To study the effects of mechanical strain on the proliferation of the human pulmonary epithelial cell and the redistribution of its membrane receptors, integrins ? 5 and ? 1. Methods A cyclic strain unit in vitro was designed. The cellular proliferative index was measured by flow cytometry and the redistribution of ? 5 and ? 1 integrins was analyzed in human pulmonary epithelial cell line H727 by laser confocal microscopy. Results The cellular proliferative index reduced significantly after cells were subjected to 15% elongation at frequencies of 20 cycles/min or 40 cycles/min for 24 h. In human pulmonary epithelial H727 cells, ? 5 and ? 1 integrins transferred from the apical layer to the basal layer and formed an adhesion plaque after 24 h exposure to 15% elongation at frequency of 40 cycles/min. Conclusion The results suggest that ? 5 and ? 1 integrins in pulmonary epithelial cells may play an important role in the transduction of mechanical stress.