Src-family kinase signaling, but not Syk or PI3K signaling, is indispensable for reorganization of macrophage surfaces. (A) Immunoblots of phosphorylated AKT in nonactivated (PLL) or hIgG-activated human macrophages pretreated with vehicle (DMSO), as a control, 10 µM PP2 (left), 100 µM piceatannol (PCT; middle), or 1 µM wortmannin (Wort; right). Blots represent two independent experiments. (B) TIRF image of FcγRI (white; bars, 20 µm) and dSTORM images (bars, 5 µm) of FcγRI (green) and SIRPα (red) at the surface of human macrophages incubated with vehicle (DMSO), PP2, PCT, or Wort, pretreated as in A. Cells were then seeded onto slides coated with PLL (nonactivated) or hIgG for 10 min and stained with anti–FcγRI-AF488 and anti–SIRPα-AF647 mAbs. In each condition, regions outlined by the white squares (middle column) are shown enlarged (right column). Bars, 1 µm. (C) CBC histograms for FcγRI and SIRPα in cells pretreated as in A and seeded onto slides coated with PLL (gray) or hIgG (DMSO, dark gray; PP2, red; PCT, green; and Wort, blue) for 10 min, as indicated. Data are from a minimum of 30 cells from three independent donors. Bars show mean ± SD. (D) NND analysis from data shown in C. Each symbol represents the median NND of all paired single-molecule localizations from one cell. Horizontal lines and error bars represent mean ± SD. ns, not significant; ****, P < 0.0001; one-way ANOVA with Tukey’s post-hoc test. (E) Histogram distributions of the NND between the centroids of nanoclusters from one channel and the centroid of their nearest neighbor from the second channel (≥20,000 clusters from a minimum of 10 cells per condition).