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Updated: Aug 5, 2026

Real-time Imaging of Heterotypic Platelet-neutrophil Interactions on the Activated Endothelium During Vascular Inflammation and Thrombus Formation in Live Mice
11:18

Real-time Imaging of Heterotypic Platelet-neutrophil Interactions on the Activated Endothelium During Vascular Inflammation and Thrombus Formation in Live Mice

Published on: April 2, 2013

Platelets secrete stromal cell-derived factor 1alpha and recruit bone marrow-derived progenitor cells to arterial

Steffen Massberg1, Ildiko Konrad, Katrin Schürzinger

  • 1Deutsches Herzzentrum and Medizinische Klinik, Technical University of Munich, D-80636 Munich, Germany. massberg@cbr.med.harvard.edu

The Journal of Experimental Medicine
|April 19, 2006
PubMed

The accumulation of smooth muscle and endothelial cells is essential for remodeling and repair of injured blood vessel walls. Bone marrow-derived progenitor cells have been implicated in vascular repair and remodeling; however, the mechanisms underlying their recruitment to the site of injury remain elusive. Here, using real-time in vivo fluorescence microscopy, we show that platelets provide the critical signal that recruits CD34+ bone marrow cells and c-Kit+ Sca-1+ Lin- bone marrow-derived progenitor cells to sites of vascular injury. Correspondingly, specific inhibition of platelet adhesion virtually abrogated the accumulation of both CD34+ and c-Kit+ Sca-1+ Lin- bone marrow-derived progenitor cells at sites of endothelial disruption. Binding of bone marrow cells to platelets involves both P-selectin and GPIIb integrin on platelets. Unexpectedly, we found that activated platelets secrete the chemokine SDF-1alpha, thereby supporting further primary adhesion and migration of progenitor cells. These findings establish the platelet as a major player in the initiation of vascular remodeling, a process of fundamental importance for vascular repair and pathological remodeling after vascular injury.

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