Analysis for Recovery and Loss of Mononuclear Cells and Colony-Forming Units Granulocyte-Macrophage during ex vivo Processing of Autologous Bone Marrow

Abstract

During ex vivo processing of autologous bone marrow (BM) substantial loss of stem and progenitor cells should be avoided to achieve rapid and sustained hematopoietic reconstitution after high-dose radio-/chemotherapy. We processed 25 autologous BM grafts with the Fresenius AS104 cell separator for cryopreservation and we determined recoveries for mononuclear cells (MNC) and colonyforming units granulocyte-macrophage (CFU-GM) in the BM concentrates. To identify cell loss in BM fractions 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 (FIM) compared with patients suffering from germ cell cancer (GCC): 66 ±21 vs. 43±12% (p<0.02). Seventeen patients (7 GCC, 10 FIM) underwent 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 patients achieved engraftment with neutrophils > 0.5 x 10^9/l at a mean of 14±6 days. We conclude that; (1) ex vivo processing of autologous BM with a mean recovery of 42% for MNC and 54% for CFU-GM in the BM concentrate can result in a cell population capable of sustained hematopoietic reconstitution, (2) CFU-GM recovery is significantly higher in patients with FIM than in patients with GCC and (3) 37% MNC and 17% CFU-GM represent in fact cell losses recovered from BM fractions not cryopreserved (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.

Comparison of two leukapheresis programs for computerized collection of blood progenitor cells on a new cell separator

“…There are limited amounts of data in the literature concerning the processing of marrow grafts and the harvesting of PBPCs on the Fresenius cell separators AS104 and AS.TEC204. 18,20,22,[36][37][38][39] Leibundgut et al 18 (AS104) and Moog et al 39 (AS.TEC204) reported on the CD34+ cell dose collected, but they provided no data concerning the CD34-CEs and the MNC/CD34+ cell percentages of the concentrates collected. Bambi and colleagues, 22 who used the LP-PBSC-Lym software on the AS104 to obtain 24 PBPC harvests from pediatric patients, achieved a mean CD34+ cell extraction efficiency of 42 percent and a MNC percentage of 78 percent in the harvested components.…”

“…There are limited amounts of data in the literature concerning the processing of marrow grafts and the harvesting of PBPCs on the Fresenius cell separators AS104 and AS.TEC204 18,20,22,36‐39 . Leibundgut et al 18 (AS104) and Moog et al 39 (AS.TEC204) reported on the CD34+ cell dose collected, but they provided no data concerning the CD34‐CEs and the MNC/CD34+ cell percentages of the concentrates collected.…”