Mobilized Leukopak (Plerixafor only). Leukopaks from mobilized peripheral blood are collected from healthy human donors under IRB approved informed consent by leukapheresis. Donors are injected with Plerixafor, which stimulates the bone marrow to produce a large number of hematopoietic and progenitor stem cells and mobilizes them into the peripheral blood stream. This mononuclear cell-rich leukapheresis product is extracted using continuous flow centrifugal technology directly into the collection bag.