Hematopoietic supportive care.

Introduction Over the past 35 or more years, mature and immature allogeneic and autologous hematopoietic cells collected from the PB3 have been used in the supportive care management of patients with therapy or disease-induced intermittent, recurrent, and often prolonged periods of BM suppression. Clinical, laboratory, and technological research has been directed into the cellular contents of the intravascular and extravascular space, where cell populations of interest in quantities ranging from l06 1012 were available for use. It is most fitting today that we pause to recognize and honor Dr. Emil Freireich for his major role in defining the principles of hematopoietic supportive care in the l960s and l970s, explore the pursuit and expansion of those principles by his students and colleagues in the l980s and 1990s, evaluate how the principles derived from those studies may remain relevant in today’s management of myelosuppressed patients, and speculate on the future of supportive care. Supportive care concepts began with the investigation of the treatment and biology of AL in the 1950s. As so aptly stated by Dr. Freireich, “When we started working on leukemia, a disease whose prime manifestation is BM failure, we realized that the morbidity and mortality from the disease was accounted for almost entirely by hemorrhage and infection” (1). He recognized that replacement of physiologically appropriate quantities of granulocytes and platelets required research into the biology, kinetics, and vascular distribution of these cells once they were transfused into neutropenic and thrombocytopenic patients, and his realization that single units of whole blood contained inadequate quantities of cells for transfusion led to his direct participation in the development of CF-BCS centrifugal technology, by which large volumes of donor blood could be processed for specific cell collection (2). Among the transfusion principles first described by Freireich for leukocytes but subsequently shown to be applicable to all other PB cell populations used for hematopoietic support were that the quantity of cells recovered in the patient’s PB related to the dose of cells transfused, and the circulating PB