Immune reactions of platelets and their clinical significance.

It is recognized that blood platelets with a peculiar cell membrane which carries numerous genetically determined immunogens, but is also intricately associated with the hemostatic process not only participate in immune reactions as a passive target cell, but also as an active functional cell. Pertinent results of animal experiments and of in vivo and in vitro investigations with human blood platelets are reviewed in the attempt to elucidate the role of immune reactions of platelets in the pathogenesis of various human bleeding disorders.