Platelets have a wide array of functions in inflammation. Which of the following are among these? a. Synthesis and release of vasoactive eicosanoids b. Release of chemotactic factors c. Adherence to and coating of bacterial and tumor cells d. Increase of vascular permeability e. Phagocytosis of bacteria

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Answer: a, b, c, d  Platelets are anucleated cells derived from megakaryocytes in the bone marrow. Their central role in hemostasis is well known. Platelets possess a wide array of functions in inflammation, including the following:   Synthesis and release of vasoactive eicosanoids   Release of chemotactic factors   Interaction with other inflammatory cells   Interaction with endothelial cells  Adherence to and coating of bacterial and tumor cells Platelets are not capable of phagocytosis. Few of the factors released or the functions carried by platelets during inflammation are unique to this cell type. Other inflammatory cells often have the same or similar capabilities. Indeed, some platelet functions may reflect vestigial functions inherited from a primitive precursor inflammatory cell. Platelets serve primarily as an amplifier or modulator of the inflammatory response

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