A comparative examination of thrombocyte/platelet immunity.

Among the cells in the blood vascular system, platelets in mammals and thrombocytes in lower vertebrates are the source of crucial mediators in hemostatic functions. Although these cells have been known to be primarily involved in thrombosis and hemostasis, platelets and thrombocytes have been shown recently to have roles in inflammatory functions and the immune response in general. Thrombocytes/platelets are widely recognized contributors to inflammatory responses upon stimulation with various microbial stimulants. In recent years, the role of platelets has been shown in adaptive immune responses. Therefore, thrombocytes/platelets should be considered as specialized immune cells that not only resemble innate effector cells in function but also have a role in affecting adaptive immunity through cellular contact and interaction with antigen presenting cells and lymphocytes.