Collection and use of circulating hematopoietic progenitor cells

Although lymphocytes and monocytes are becoming increasingly important in transfusion therapy, peripheral stem cells have been responsible for the recent explosive interest in harvesting mononuclear cells from the peripheral circulation. Despite their low concentration in peripheral blood and the consequent difficulty in cell collection, circulating hematopoietic progenitor cells are collected and used almost routinely. The mononuclear cells, possessing the capacity for hematopoietic reconstitution and the potential for definitive therapy of a variety of disorders, have been the focus of recent intense interest in transfusion medicine.