Fig. 4

Structural cues in collagen networks do not enhance macrophage (Mϕ) migration to myofibroblasts (MFs). a MFs remodeled collagen extracellular matrix (ECM) for 1–18 h. b Confocal reflection microscopic images were taken of collagen ECM, remodeled by MF (in image center) after 1, 3, 6, and 18 h; higher magnifications of the boxed regions are shown inverted to highlight fibrillar collagen. c Collagen fiber alignment and radius of the structural changes in the ECM were calculated and plotted over time of MF remodeling. Data points are averages ± SD (**p ≤ 0.01 using analysis of variance followed by post hoc Tukey’s multiple comparison test). d MFs were allowed to remodel collagen ECM for 1–18 h prior to adding Mϕ that were then tracked for another 8 h. e Trajectories of migratory Mϕ are plotted with respect of the MF position as a function of pre-remodeling time. f Percentages of attracted, responsive, and non-responsive Mϕ are shown for the different ECM remodeling states (pie charts) and the percentage of attracted Mϕ was plotted as a function of collagen fiber alignment calculated from confocal reflectance images. g Local Mϕ migration velocities, corrected for ECM dragging, were plotted as a function of distance to the MF for every pre-remodeling condition. h Migration angles were plotted as a function of distance to the MF. Data points are medians with error bars representing minima and maxima (93 Mϕ, 20 independent experiments). Slope changes were considered significant at *p ≤ 0.05, using slope comparison test. All scale bars: 100 µm