Isolation of Primary Megakaryocytes and Studies of Proplatelet Formation

Bone marrow megakaryocytes were first described well over one hundred years ago (1 ,2 ) and it is almost one hundred years since their role in platelet formation was first appreciated (3 ,4 ). Prior to the development of megakaryocyte isolation techniques, a great deal had been learned about megakaryocyte structure and megakaryocytopoiesis using electron microscopy and in vivo experimentation. However, the development of isolation techniques opened up entirely new areas of research on megakaryocytes. Megakaryocyte isolation has been a challenge due to the fragile nature of megakaryocytes and their relative rarity, constituting less than 1% of the nucleated cells in mammalian bone marrow. Nevertheless, techniques including density gradient centrifugation, centrifugal elutriation, selective aggregation, and immunomagnetic bead isolation have been described for megakaryocyte isolation from murine, rat, guinea pig, bovine, and human tissue (5 –23 ).