Dynamics of adhesive rupture between fibroblasts and fibronectin: microplate manipulations and deterministic model.
Eur Biophys J. 2000-09-22; 29(6): 409-419
DOI: 10.1007/pl00006648
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1. Eur Biophys J. 2000;29(6):409-19.
Dynamics of adhesive rupture between fibroblasts and fibronectin: microplate
manipulations and deterministic model.
Thoumine O(1), Meister JJ.
Author information:
(1)Biomedical Engineering Laboratory, Swiss Federal Institute of Technology,
Lausanne.
To characterize the dynamics of cell-substrate adhesive rupture, we used a novel
micromanipulation technique, in which individual fibroblasts seized on a rigid
microplate were placed into contact with a fibronectin-coated flexible
microplate, then pulled away. The fibronectin density (0-3000 molecules/microm2)
and the pulling rate (1-10 microm/s) were controlled. The extent of the contact
zone decreased to zero at a time threshold corresponding to adhesive rupture. The
uniaxial force at the interface, computed from the deflection of the microplate,
increased linearly with time and reached a maximum before dropping to zero. A
deterministic model, focusing on the mean number of bonds between fibronectin and
its membrane receptor on the cell surface, shows rapid rupture when the force
reaches a critical value, in agreement with experimental observations. Increasing
the ligand density and the rate of load raises the maximal force (30 200 nN), in
reasonably good agreement with the model predictions. Minimization of error
between experimental and simulated forces allowed identification of two
physicochemical properties of the bond, i.e. its association rate constant
(k(2D)on = 3 x 10(-4) microm2/s) and structural length (d = 3 nm). These results
may help understand better fibroblast locomotion and interaction with the
extracellular matrix.
DOI: 10.1007/pl00006648
PMID: 11081402 [Indexed for MEDLINE]