Figure 3

Locomotory behavior at a chemical barrier.

(a) Fluorescence image of the ring-shaped patterns consisting of labeled fibronectin including a PLL-PEG coated gap of 13 μm width. (b) Time series depicting alternative behaviors at the barrier: reversal (top) and traversal of the barrier (bottom). (c) Typical trajectory of a cell migrating in ring-shaped lanes interrupted by a 13-μm gap. (d) Frequency of cells in the run or rest state plotted against the distance of a 19-μm gap. More than 50 μm away from the barrier most cells are in the run state, while closer than 50 μm to the barrier most cells are in the rest state. (e) Probability P_trans of overcoming a PEG barrier of width d_gap. P_trans is well fitted by an exponential function (dashed line). (f) The ability of cells to penetrate into the PEGylated area at the end of stripes coated with fibronectin is shown by the survival function S_inv(d) = P(d_inv > d). The dashed line represents an exponential fit.