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Platelet PECAM-1 inhibits thrombus formation in vivo.

ABSTRACT: Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell surface glycoprotein receptor expressed on a range of blood cells, including platelets, and on vascular endothelial cells. PECAM-1 possesses adhesive and signaling properties, the latter being mediated by immunoreceptor tyrosine-based inhibitory motifs present on the cytoplasmic tail of the protein. Recent studies in vitro have demonstrated that PECAM-1 signaling inhibits the aggregation of platelets. In the present study we have used PECAM-1-deficient mice and radiation chimeras to investigate the function of this receptor in the regulation of thrombus formation. Using intravital microscopy and laser-induced injury to cremaster muscle arterioles, we show that thrombi formed in PECAM-1-deficient mice were larger, formed more rapidly than in control mice, and were more stable. Larger thrombi were also formed in control mice that received transplants of PECAM-1-deficient bone marrow, in comparison to mice that received control transplants. A ferric chloride model of thrombosis was used to investigate thrombus formation in carotid arteries. In PECAM-1-deficient mice the time to 75% vessel occlusion was significantly shorter than in control mice. These data provide evidence for the involvement of platelet PECAM-1 in the negative regulation of thrombus formation.

SUBMITTER: Falati S

PROVIDER: S-EPMC1895610 | biostudies-literature | 2006 Jan

REPOSITORIES: biostudies-literature

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Platelet PECAM-1 inhibits thrombus formation in vivo.

Falati Shahrokh S Patil Sonali S Gross Peter L PL Stapleton Michelle M Merrill-Skoloff Glenn G Barrett Natasha E NE Pixton Katherine L KL Weiler Harmut H Cooley Brian B Newman Debra K DK Newman Peter J PJ Furie Barbara C BC Furie Bruce B Gibbins Jonathan M JM

Blood 20050915 2

Platelet endothelial cell adhesion molecule-1 (PECAM-1) is a cell surface glycoprotein receptor expressed on a range of blood cells, including platelets, and on vascular endothelial cells. PECAM-1 possesses adhesive and signaling properties, the latter being mediated by immunoreceptor tyrosine-based inhibitory motifs present on the cytoplasmic tail of the protein. Recent studies in vitro have demonstrated that PECAM-1 signaling inhibits the aggregation of platelets. In the present study we have ...[more]

PMID: 16166583

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Platelet PECAM-1 inhibits thrombus formation in vivo.

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Platelet PECAM-1 inhibits thrombus formation in vivo.

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