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Updated: Aug 10, 2026

Adhesion Frequency Assay for In Situ Kinetics Analysis of Cross-Junctional Molecular Interactions at the Cell-Cell Interface
Published on: November 2, 2011
Surface densities of ephrin-B1 determine EphB1-coupled activation of cell attachment through alphavbeta3 and
U Huynh-Do1, E Stein, A A Lane
1Division of Nephrology, Departments of Medicine and Cell Biology, and the Vanderbilt Cancer Center, Vanderbilt University Medical Center, Nashville, TN 37232-2372, USA.
Abstract:
Receptors of the Eph family and their ligands (ephrins) mediate developmental vascular assembly and direct axonal guidance. Migrating cell processes identify appropriate targets within migratory fields based on topographically displayed ephrin gradients. Here, EphB1 regulated cell attachment by discriminating the density at which ephrin-B1 was displayed on a reconstituted surface. EphB1-ephrin-B1 engagement did not promote cell attachment through mechanical tethering, but did activate integrin-mediated attachment. In endothelial cells, attachment to RGD peptides or fibrinogen was mediated through alphavbeta3 integrin. EphB1 transfection conferred ephrin-B1-responsive activation of alpha5beta1 integrin-mediated cell attachment in human embryonic kidney cells. Activation-competent but signaling-defective EphB1 point mutants failed to stimulate ephrin-B1 dependent attachment. These findings lead us to propose that EphB1 functions as a 'ligand density sensor' to signal integrin-mediated cell-matrix attachment.
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