Impact of harvest product volume in erythrocyte depletion of allogeneic or autologous bone marrow using COBE spectra

Abstract

Depletion of bone marrow (BM) from erythrocytes is used to prevent early hemolysis in major ABO incompatible allogeneic hematopoietic cell transplantation (Allo-HCT). This method was also strongly recommended before storing of autologous and even allo-BM for volume reduction in order to prevent early hemolysis and DMSO toxicity after infusion. In our center, erythrocyte depletion of BM harvests has been performed on a continuous flow cell separator, which used a closed system with a high mononuclear cell (MNC) yield and low rate of erythrocyte contamination. According to the protocol of a cellular therapy approach in a cardiovascular collaborative study we have to adopt the process to lower volumes. We aimed to compare our results with standard volume (SV) (historical control) to low volume ED procedures. Patients and method Data has been collected from the last five years. We analyzed 28 cases in the SV group (BM volume >750 ml) and 39 cases in the low volume (LV) group. Nineteen of these cases were allogeneic, and 48 were autologous procedures. We used the software COBE PBSC coll vers 5.1 and a standard disposable set (Gambro BCT, Lakewood, USA) for the procedure, and simultaneously, a double bag system with intermediate connectors were used to overcome re-circulation (COBE Spectra Bone Marrow Processing Set, Lakewood USA). Results The mean volume reduction was 88% (range, 84.4–93.5%) for SV and 90.8% (range, 87.2–91.3%) for the LV group. We did not find any significant difference for MNC yield, volume reduction rate and CD34+ cell recovery between the SV and LV group. There were no complications experienced with regards to device or technical difficulties during procedures. Acute massive intravascular hemolysis was not observed in allogeneic recipients. Conclusion ED and volume reduction with COBE spectra produced successful results in standard and low harvest volumes. This process can be successfully applied to lower volumes and comparable results to the SV harvest can be achieved for the ED rate, reduction of volume and recovery of MNCs and CD34+ cells.