Concentration of Human Hematopoietic Stem Cells in Bone Marrow Transplantation: Results of a Multicenter Study Using Baxter CS 3000 plus Cell Separator

: Preliminary BM processing to produce an enriched MNC fraction from large BM volumes improves subsequent pharmacological and/or immunological "ex vivo" treatment and cryopreservation. We detail on a multicenter study (6 Transplant Centers) performed to establish an effective and reliable protocol using a CS 3000 continuous flow separator on a large series of BM processed for autologous (96) and allogeneic (12) transplantation. The reduction in volume was 78.6 + 7.2% while 28.9 + 12.4% of the original nucleated cells were found in the final product. A mean of 84.3 + 13.2% of the staring MNC was yielded in a fraction containing over 81% MNC. Cloning efficiency indicated than the final graft was highly enriched in progenitor cells committed to the granulocyte/macrophage pathway (> 100%) as assessed in vitro (CFU-GM). Removal of RBC and PLT was 98.3 + 1.1 and 37.7 + 14.6%, respectively. The mean dose of MNC and CFU-GM was 0.6 + 0.37 x 10(8) and 0.96 + 1 x 10(5) recipient weight. The entire process was accomplished in 87.5 + 20 min. We concluded that this automated device is a simple and reproducible method for BM processing suitable as first step for further "ex vivo" automated negative and/or positive cell selections.