Platelet-Leukocyte-Endothelial Cell Interactions After Middle Cerebral Artery Occlusion and Reperfusion

• Published in: Journal of cerebral blood flow and metabolism 2004-08, Vol.24 (8), p.907-915
• Main Authors: Ishikawa, Mami, Cooper, Dianne, Arumugam, Thiruma V., Zhang, John H., Nanda, Anil, Granger, D. Neil
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Blood Platelets - metabolism; Cell Adhesion - physiology; Cell Communication - physiology; Endothelial Cells - metabolism; Infarction, Middle Cerebral Artery - physiopathology; Leukocytes - metabolism; Male; Medical sciences; Mice; Microscopy, Fluorescence; Microscopy, Video; Neurology; Neutrophil Infiltration; P-Selectin - immunology; P-Selectin - metabolism; Platelet Glycoprotein GPIIb-IIIa Complex - immunology; Platelet Glycoprotein GPIIb-IIIa Complex - metabolism; Reperfusion Injury - physiopathology; Time Factors; Transplantation Chimera; Vascular diseases and vascular malformations of the nervous system
• ISSN: 0271-678X; 1559-7016
• DOI: 10.1097/01.WCB.0000132690.96836.7F

The adhesion of both leukocytes and platelets to microvascular endothelial cells has been implicated in the pathogenesis of ischemia/reperfusion (I/R) injury in several vascular beds. The objectives of this study were to (1) assess the platelet–leukocyte–endothelial cell interactions induced in the cerebral microvasculature by middle cerebral artery occlusion (MCAO)/reperfusion, and (2) define the molecular determinants of the prothrombogenic and inflammatory responses in this model of focal I/R. MCAO was induced for 1 hour in wild-type (WT) mice, WT mice treated with a monoclonal antibody (mAb) to either P-selectin or GPIIb/IIIa, and in P-selectin−/−(P-sel−/−) chimeras. Isolated platelets labeled with carboxyfluorescein diacetate succinimidyl ester (CFDASE) were administered intravenously and observed with intravital fluorescence microscopy. Leukocytes were observed after intravenous injection of rhodamine 6G. One hour of MCAO followed by 1 hour of reperfusion resulted in the rolling and adhesion of leukocytes in venules, and after 4 hours of reperfusion, the adhesion of both leukocytes and platelets was detected. Although both the P-selectin and GPIIb/IIIa mAbs significantly reduced the adhesion of leukocytes and platelets at 4 hours of reperfusion, the antiadhesive effects of the P-selectin mAb were much greater. The leukocyte and platelet adhesion responses were significantly attenuated in both P-sel−/−→WT and WT→P-sel−/− bone marrow chimeras, compared with WT→WT chimeras. Neutropenia, induced by antineutrophil serum treatment, also reduced the recruitment of leukocytes and platelets after cerebral I/R. These findings implicate a major role for both platelet-associated and endothelial cell–associated P-selectin, as well as neutrophils in the inflammatory and prothrombogenic responses in the microcirculation after focal cerebral I/R.