Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
BP: Fachverband Biologische Physik
BP 22: Cell Mechanics
BP 22.1: Vortrag
Donnerstag, 28. Februar 2008, 10:30–10:45, PC 203
Shear Rheology of a Cell Monolayer — Pablo Fernandez1, Lutz Heymann2, •Benjamin Tränkle3, Albrecht Ott3,4, Nuri Aksel2, and Pramod Pullarkat5 — 1E22 Biophysik, Technische Universität München, D-85748 Garching — 2Technische Mechanik und Strömungsmechanik, Universität Bayreuth, D-95440 Bayreuth — 3Experimentalphysik I, Universität Bayreuth, D-95440 Bayreuth — 4Biologische Experimentalphysik, Universität des Saarlandes, D-66041 Saarbrücken — 5on leave from Experimentalphysik I, Universität Bayreuth, D-95440 Bayreuth
We report a systematic investigation of the mechanical properties of fibroblast cells using a novel Cell Monolayer Rheology (CMR) technique. The new technique provides quantitative rheological parameters averaged over ∼ 106 cells, making the experiments highly reproducible. Using this method, we are able to explore a broad range of cell responses not accessible using other present day techniques. Within the explored strain rates (10−3–1 s−1) and strain amplitudes (1%–100%), nonlinear behaviour is only revealed by the effect of a nonzero average stress on the response to small, fast deformations. The response becomes linear at long timescales as well as large amplitudes. This counterintuitive linear behaviour is due to the dynamic nature of the cell cytoskeletal crosslinks and/or filaments, since it can be abolished by making them permanent with a fixation agent. These experiments provide a broad framework for understanding the mechanical responses of the cytoskeleton to different imposed mechanical stimuli.