ANALYSIS FOR RECOVERY AND LOSS OF MONONUCLEAR-CELLS AND COLONY-FORMING-UNITS GRANULOCYTE-MACROPHAGE DURING EX-VIVO PROCESSING OF AUTOLOGOUSBONE-MARROW

During ex vivo processing of autologous bone marrow (BM) substantial l oss of stem and progenitor cells should be avoided to achieve rapid an d sustained hematopoietic reconstitution after high-dose radio-/chemot herapy. We processed 25 autologous BM grafts with the Fresenius AS104 cell separator for cryopreservation and we determined recoveries for m ononuclear cells (MNC) and colony-forming units granulocyte-macrophage (CFU-GM) in the BM concentrates. To identify cell loss in BM fraction s not cryopreserved, we investigated the MNC and CFU-GM content of BM fat and BM blood. MNC and CFU-GM recovery yielded a mean (+/- SEM) of 42+/-12 and 54+/-20% in the BM concentrate. BM fat showed a mean loss of 7+/-5% for MNC and 4+/-3% for CFU-GM, BM blood 30+/-12% for MNC and 13+/-13% for CFU-GM, respectively. CFU-GM recovery was significantly higher in the BM concentrate of patients with hematologic malignancy ( HM) compared with patients suffering from germ cell cancer (GCC): 66+/ -21 vs. 43+/-12% (p < 0.02). Seventeen patients (7 GCC, 10 HM) underwe nt high-dose chemotherapy or radio-/chemotherapy and were autografted with 0.8+/-0.2x10(8) MNC/kg and 3.7+/-2.0x10(4) CFU-GM/kg. All patient s achieved engraftment with neutrophils >0.5x10(9)/l at a mean of 14+/ -6 days. We conclude that: (1) ex vivo processing of autologous BM wit h a mean recovery of 42% for MNC and 54% for CFU-GM in the BM concentr ate can result in a cell population capable of sustained hematopoietic reconstitution, (2) CFU-GM recovery is significantly higher in patien ts with HM than in patients with GCC and (3) 37% MNC and 17% CFU-GM re present in fact cell losses recovered from BM fractions not cryopreser ved (BM fat, BM blood). Furthermore, it is likely that MNC and CFU-GM not recovered from BM concentrate, BM fat and BM blood are cell losses related to the cell separator.