Endothelial Cell Morphological Response to Cyclic Strain -- Effect of Substratum Adhesiveness and Focal Adhesion Proteins
Date of Award
Doctor of Philosophy (PhD)
In response to mechanical stimuli, endothelial cells exhibit changes in morphology and cytoskeletal organization. When subjected to cyclic mechanical stretching, time-lapse imaging revealed that endothelial cells underwent significant shape changes with their resultant long axes aligned away from the strain direction. Although this type of response is not the same as motility, it could be governed by motility-related factors such as substratum adhesiveness and focal adhesion proteins. To examine this, human aortic endothelial cells were uniaxially, cyclically stretched on silicone rubber membranes coated with various concentrations of fibronectin, collagen type IV and laminin to produce differing amounts of adhesiveness. For each type of protein there was a parabolic dependence on initial adhesiveness with optimal cell orientation occurring at similar adhesive strengths. This suggests that, like motility, the extent of endothelial cell orientation in response to cyclic stretching is determined, in part, by the cell-substratum adhesiveness.
Frank C-P Yin
Genin, Gregory Longmore, Jin-Yu Shao