Sema7A is required for neutrophil adhesion and migration during inflammation. (A) Histological cross-sections and magnifications of lung tissue from WT and Sema7A^−/− mice 24 hours after the instillation of 4 × 10⁷ cells of K pneumoniae (scale bar, 200 μm). (B) IF staining of Sema7A (green) and vWF (red) in endothelial cells of murine lung tissue and nuclear staining with DAPI (4′,6-diamidino-2-phenylindole; blue; scale bar, 20 μm). (C) IF staining showing Sema7A expression (green) on the surface of human CD45-marked PMNs, (red) treated with NaCl or fMLP for 15 minutes (scale bar, 10 μm). (D) Representative video images of PNCs in murine lungs after LPS instillation with additional recombinant Sema7A or IgG_2A-Fc (controls) treatment after 30 minutes (scale bar, 30 μm). (E) Total neutrophil area coverage, total and adhesive platelet area coverage, and the fractions of PNCs formed in the lung as determined via intravital confocal microscopic analysis of the lung in WT mice instilled with 5 μg/g BW LPS, with or without additional treatment with recombinant Sema7A (the data are the mean ± SD). ∗P < .05; ∗∗P < .01; ∗∗∗P < .001 as indicated. Fc, control fragment; IF, immunofluorescence; vWF, von Willebrand Factor.