Fig. 1: Neutrophils penetrate the endothelium at hotspots during the early stage of inflammation. | Experimental & Molecular Medicine

Fig. 1: Neutrophils penetrate the endothelium at hotspots during the early stage of inflammation.

From: LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) distinctly regulate neutrophil extravasation through hotspots I and II

Fig. 1

a Analysis of neutrophil infiltration at a hotspot from the cremaster muscle blood vessel stimulated with N-formylmethionyl-leucyl-phenylalanine (fMLP). Dotted circles indicate neutrophils from the same hotspot. Scale bar, 50 μm. b The tracks of six extravasating neutrophils overlapped, indicating that neutrophils penetrated through a hotspot. a, b were analyzed from Video 1. c Hotspots were counted per 100 μm of blood vessels upon stimulation with C-X-C chemokine motif ligand 2 (CXCL2), fMLP, and tumor necrosis factor α (TNFα). d The numbers of neutrophils undergoing extravasation per hotspot were determined upon stimulation with CXCL2, fMLP, and TNFα. *P < 0.005. e Neutrophils penetrated the endothelial cell layer at a hotspot in the early stage of inflammation. Two-photon intravital imaging of LysM-GFP mice was performed upon stimulation with fMLP. Scale bar, 30 μm. See Video 2. f Analysis of neutrophil infiltration at a hotspot region vs. non-hotspot region at each time point upon stimulation with fMLP. g The accumulated number of neutrophils undergoing extravasation with increasing time after stimulation. f, g were analyzed from Video 2. Representative data from five independently repeated experiments are shown