Platelets as initiators and mediators of inflammation at the vessel wall

Abstract

Platelets are dynamic cells with activities that extend beyond thrombosis including an important role in initiating and sustaining vascular inflammation. A role for platelets has been described in many physiologic and pathophysiologic processes such as atherosclerosis, stem cell trafficking, tumor metastasis, and arthritis. Platelet activation at sites of an intact inflamed endothelium contributes to vascular inflammation and vascular wall remodeling. Platelets secrete a wide array of preformed and synthesized inflammatory mediators upon activation that can exert significant local and systemic effects. This review will focus on the role of platelet derived mediators in vascular inflammation and vascular wall remodeling.

Figure 1

Non-Occlusive thrombi are present within cerebral vessels of mice with experimental cerebral malaria and within vessels of skin grafts during rejection (immunohistochemical staining for vWF). Arrowheads indicate vWF rich thrombi and arrows enmeshed leukocytes.