C. Selhuber-Unkel, T. Erdmann, M. Lopez-Garcia, H. Kessler,
U.S. Schwarz and J.P. Spatz

Cell Adhesion Strength Is Controlled by Intermolecular Spacing of
Adhesion Receptors

Biophysical Journal, Volume 98, Issue 4, 543-551, 17 February 2010

Spatial patterning of biochemical cues on the micro- and nanometer
scale controls numerous cellular processes such as spreading,
adhesion, migration, and proliferation. Using force microscopy we show
that the lateral spacing of individual integrin receptor-ligand bonds
determines the strength of cell adhesion. For spacings > 90 nm, focal
contact formation was inhibited and the detachment forces as well as
the stiffness of the cell body were significantly decreased compared
to spacings < 50 nm. Analyzing cell detachment at the subcellular level
revealed that rupture forces of focal contacts increase with loading
rate as predicted by a theoretical model for adhesion
clusters. Furthermore, we show that the weak link between the intra-
and extracellular space is at the intracellular side of a focal
contact. Our results show that cells can amplify small differences in
adhesive cues to large differences in cell adhesion strength.