Preface

Mammalian platelets are small (2–4 um), discoid, short-lived fragments derived from megakaryocyte precursors. They play a crucial role not only in the formation of a normal hemostatic plug but also in the formation of a pathologic thrombus, particularly within arteries subjected to high shear stress. Platelets circulate in a resting state through blood vessels lined by an endothelial layer. Following an insult to the endothelial layer platelets undergo a series of changes that ultimately lead to them changing shape, secreting their granule contents, and aggregating to prevent blood loss. Thus, platelets rely on specific adhesive interactions with extracellular matrices (e.g., collagen, von Willebrand factor, fibronectin). In order to achieve firm adhesion, platelets possess many receptors specific for extracellular matrix proteins. As our basic knowledge in platelet biology has improved through the years, it is has become evident that the role of platelets extends beyond that of thrombosis and hemostasis. Current state of the art suggests that platelets play a key role in a much wider repertoire of physiological processes such as inflammation, innate immunity, cancer, infection, neurobiology, and tissue repair/regeneration.

The individual chapters in this book identify one particular aspect of platelet function, dysfunction, or application. The book is not intended to be read from cover to cover as the reader seeks authoritative information on any one given aspect of platelets. Therefore, for ease of reading, the book is divided into three main sections: "Platelet Function" and "Platelet Dysfunction" and "Platelet Application." The authors of each of the focused chapters are leaders in their respective fields. As significant advances continue to develop our thinking of the functional role of platelets in health and disease, this book elevates awareness and enthusiasm in further investigating platelet functions.

**II**

**Chapter 8 151**

Rapid Cytoreduction by Plateletapheresis in the Treatment

*by Bela Balint, Mirjana Pavlovic and Milena Todorovic*

of Thrombocythemia

**Steven W. Kerrigan** Professor, Head of the Cardiovascular Infection Research Group, RCSI University of Medicine and Health Sciences, Dublin, Ireland

**1**

Section 1

Platelet Function
