Improving bone marrow (BM) processing cd34+ cell recovery using the terumo optia

Background/Case Studies: Allogeneic bone marrow transplant (BMT) is performed to treat many hematological disorders. After harvesting the bone marrow (BM), it must be processed to reduce red blood cells (RBCs) for ABO incompatibility, to reduce volume for overload especially in pediatric patients, or to reduce volume and RBCs prior to cryopreservation. The need to cryopreserve the BM buffy coat has become more prevalent due to COVID this past year. The post processing results using the Terumo Optia instrument and the additional kit (BMP Accessory Set) as compared to the buffy coat processing using our traditional method with the Terumo 2991 was evaluated. Study Design/Methods: A retrospective comparison of data was evaluated from 35 bone marrow buffy coats processed on the Terumo 2991 and 36 bone marrows processed on the Terumo Optia. The Terumo 2991 uses a Blood Cell Processing Set and the Terumo Optia uses an IDL Set and a BMP Accessory Set with the standard filler. Post processing comparisons of volume, TNC, hematocrit, and CD34+ cell counts were performed. The 35 bone marrows processed on the Terumo 2991 were from January 2018 through February 2020. The 36 bone marrows processed on the Terumo Optia were from March 2020 to April 2021. Results/Findings: The data using the Terumo 2991on 35 products had an average final volume of 160 mL, average RBC dose of 0.28 mL/Kg, an average TNC recovery of 73% and an average CD34 recovery of 78%. The data using the Terumo Optia on 36 products processed had an average final volume of 130 mL, an average RBC dose of 0.24 mL/Kg, an average TNC recovery of 76% and an average CD34 recovery of 91%. Conclusions: The use of BM as the source of stem cells used in transplantation has recently increased, and improved methods of processing to increase CD34+ recovery is desired. Our results show that processing marrows on the Optia resulted in an improved recovery of CD34+ cells compared to processing on the Terumo 2991. The 91% CD34+ recovery on the Optia compared to 78% on the 2991 could be clinically significant for patient engraftment. When required to cryopreserve the marrow due to COVID precautions or for pediatric infusions, the Optia also provided a reduced final volume. Although the TNC recovery and reduced RBC content when using the Optia were slightly better, the results were minimal and clinically insignificant.