Dresden 2006 – scientific programme
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AKB: Biologische Physik
AKB 11: Cell Adhesion I
AKB 11.1: Talk
Tuesday, March 28, 2006, 12:00–12:15, ZEU 260
Cellular Unbinding Forces on Biofunctionalized Nanostructured Substrates — •Christine Selhuber1, Nadine Walter1, and Joachim P. Spatz1,2 — 1University of Heidelberg, Biophysical Chemistry, INF 253, D - 69120 Heidelberg — 2Max-Planck-Institute for Metals Research, Heisenbergstrasse 3, D-70569 Stuttgart
The adhesion of cells to substrates is a highly complex biological process and a fundamental step for many cell activities. To explore integrin mediated adhesion we investigate cell adhesion as a function of defined ligand distances.
To generate ligand patterns, we apply a nanolithographical technique that is based on the self-assembly of diblock copolymers. The result is a pattern of hexagonally arranged gold dots, where the separation of the dots is controlled over a wide length scale. The gold dots are functionalized with an RGD peptide to create adhesive patches for cellular integrin receptors. Cell culture experiments have shown that a dot separation of more than 73 nm restricts cell adhesion, cell spreading and focal contact formation.
To quantify the regulation of cell adhesion by specific nanostructures, we study unbinding forces of cells both during initial and long-term adhesion. The unbinding forces are measured with magnetic tweezers and AFM, respectively. For both adhesion periods the experiments reveal a strong dependence of unbinding forces on ligand distance.
The results indicate that characterizing adhesion forces is a suitable method for probing cell adhesion properties as a function of substrate preparation.