Figure 2.

Adhesion strength can be titrated but is independent of the matrix ligand type. (A) Representative plot for MDAMB231 cells bound to fibronectin-coated coverslips versus the applied shear. Each color corresponds to the indicated cation condition; τ₂₅ is indicated. (B) Plot of the average τ₂₅ adhesion strength for MDAMB231 cells bound to fibronectin-coated coverslips versus cation concentration. The data are plotted separately for modulation of Mg²⁺ (black squares) or Ca²⁺ (red circles), but the sigmoidal fit is for the combined data. The cation concentration range for the indicated tissue is provided for reference based on Seltzer et al. (18, 19). (C) Representative plot for MDAMB231 cells bound to collagen type I-coated coverslips versus the applied shear. Each color corresponds to the indicated cation condition; τ₂₅ is indicated. (D) Plot of the average τ₂₅ adhesion strength for MDAMB231 cells bound to collagen type I-coated coverslips versus cation concentration. The data are plotted separately for modulation of Mg²⁺ (black squares) or Ca²⁺ (red circles), but the sigmoidal fit is for the combined data. All shear plots represent binned averages from biological triplicate experiments performed across multiple, overlapping shear ranges. All other plots have n > 3. To see this figure in color, go online.