SINGLE CELL MECHANICS

摘要

In tissues or blood vessels properties and functionalities of cells are influenced substantially by frequent mechanical perturbations. We describe a cantilever-based technique which allows to precisely manipulate a single cell in model experiments in vitro that mimic mechanical situations in vivo. Cell mechanical responses are evaluated under physiological conditions by separating between two basic mechanical perturbations that are constant mechanical stress or constant cell shape deformation. The essential requirements for these investigations are the development of an automated cell force and deformation detection by fiber optics, a feedback loop, and sufficient mechanical stability of the setup under thermal gradients caused by its local heating apart from room temperature to 37℃. Thus, we can discriminate between elastic behavior of a cell, viscoelastic flow at constant strain and active cell responses at both, constant strain or stress. Such quantitative stress-strain data are applied to test physical models that describe cellular responses to mechanical stimuli. Parallel to mechanical characterization, the cell is visualized by optical microscopy which allows concurrent observations of cell shape and, intracellular morphological changes.