Combination of fluid and solid mechanical stresses contribute to cell death and detachment in a microfluidic alveolar modelElectronic supplementary information (ESI) available: Fig S1. Cell Growth, Fig S2. Meniscus Position and Velocity, Fig S3. Modeling Solid Mechanical Strain, Fig S4. Replicating Fluid Stresses, Fig S5. Linear Strain under Normal Breathing and Pathologic Ventilation, Fig S6. A549 Morphological Changes, S7. Primary, murine AECs Morphological Changes, Fig S8. Effect of Surface Tension on Fluid Mechanical Stresses, Fig S9. Surfactant-enrichedPlug Formation, Fig S10. Distance from Bulge to Centerline as a function of Time, Fig S11. Effect of Surfactant on Wall Stresses and gradients. See DOI: 10.1039/c0lc00251h

Studies using this micro-system demonstrated significant morphological differences between alveolar epithelial cells (transformed human alveolar epithelial cell line, A549 and primary murine alveolar epithelial cells, AECs) exposed to combination of solid mechanical and surface-tension stresses (cyclic propagation of air–liquid interface and wall stretch) compared to cell populations exposed solely to cyclic stretch. We have also measured significant differences in both cell death and cell detachment rates in cell monolayers experiencing combination of stresses. This research describes new tools for studying the combined effects of fluid mechanical and solid mechanical stress on alveolar cells. It also highlights the role that surface tension forces may play in the development of clinical pathology, especially under conditions of surfactant dysfunction. The results support the need for further research and improved understanding on techniques to reduce and eliminate fluid stresses in clinical settings. [ABSTRACT FROM AUTHOR]