Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 9: Physics of Cells I

BP 9.10: Vortrag

Dienstag, 23. März 2010, 12:15–12:30, H43

Force transduction in blood platelets — •Sarah Schwarz G. Henriques¹, Hansjörg Schwertz², Alexander Strate³, and Sarah Köster¹ — ¹Courant Research Centre Nano-Spectroscopy and X-Ray Imaging, Universität Göttingen, Germany — ²Division of Vascular Surgery, University of Utah, Salt Lake City, United States of America — ³Transfusion Department, University Clinic, Universität Göttingen, Germany

Blood platelets (thrombocytes) are essential for the repair of damaged blood vessels. When they become activated to form a blood clot they change their shape within minutes by dramatically rebuilding their cytoskeleton. This highly dynamic non-equilibrium process is known to be triggered by external cues and driven by cellular forces, but the basic mechanical principles are not yet understood. In our experiments we investigate the physics underlying platelet activation by measuring the forces, which platelets impose on their environment. To this end, we use traction force microscopy, a well-established technique, in which the cells are placed on thin PAA (polyacrylamide) gels of a known elastic modulus. Fluorescent tracer beads are embedded into the PAA to visualize gel deformations, which are then translated into traction force fields. In addition to measuring traction force fields, we take fluorescence microscopy images of the platelets at different activation stages. Both vinculin as well as actin are previously stained in order to map focal adhesion sites and conclude upon cytoskeletal reorganization steps. Our experimental findings are finally gathered into a mechanical model for the early stages of platelet activation.