Figure 1.

Chemotactic signaling efficiency depends on PDGF concentration and individual cell properties. (A and B), the intracellular PI3K signaling gradient, Δm, is normalized by the PDGF gradient steepness δ (Eq. 4) as a measure of chemotactic signaling efficiency. The solid black curve shows Δm/δ for the base scenario, with r_max = e_max = p_max = 1, and the dashed curve shows r/r_max as a function of u (Eq. 1) on the same scale. (A) the values of r_max are 1/3, 1 and 3, with e_max = p_max = 1. (B) the values of e_max are 1/3, 1 and 3, with r_max = p_max = 1. (C and D) effect of varying r_max and e_max, homogeneously throughout the cell population, on cell invasiveness. As in ref. 11, the maximum depth into the wound where the dimensionless cell density v = 0.5 at t = 10 days is used as a metric of invasion rate. The results show good agreement between the current hybrid model (HM; circles) and the previously published deterministic model (DM; stars).