Correlation of migration rates with pore cross section, but not scaffold stiffness. (A) Migration rates as a function of pore cross section in mononuclear tumor cells, T-blasts, and PMN in rat tail collagen of different density in the presence of GM6001. Speed was normalized to the maximum speed in low-density matrix (0.3 mg/ml) as 100% reference, and the subtotal and absolute migration limits are indicated (dotted lines). Data points depict medians from Figs. 1 E, 2 D, 5 (B, D, and F); S2 G, and S4 A. For T-blasts and PMN, data points were included for additional pore size conditions, n = 2–4. Subtotal limits were reached at median pore cross sections of 4–7 µm² for tumor cells and 3–4 µm² for leukocytes, and absolute limits at 2 µm² for leukocytes. (B) Association of migration rates and elastic modulus of 3D collagen lattices. Speed medians were used from Fig. 2 (A, C, and E) obtained for cells migrating in the presence of GM6001 in lattice conditions for which the elastic modulus was measured (compare Fig. 1 C). R² for linear regression (black line) was 0.2339 (nonsignificant).