Human bone marrow processing using a new continuous-flow cell separation device

ABO-mismatched marrow processing for transplantation: Comparative results of 80 procedures performed with Cobe Spectra and Spectra Optia

BACKGROUND

removal of incompatible red blood cells (RBCs) or plasma is usually required to avoid hemolysis during infusion of ABO incompatible bone marrow (BM) allogeneic transplants. This process often involves separation of buffy coat (BC) by centrifugation in automated devices. We have evaluated the Spectra Optia™ (Optia) apheresis system to determine its effectiveness in BC concentration, volume reduction and RBCs depletion of ABO-incompatible BM compared with our previous method using Cobe Spectra™ (Cobe).

MATERIALS AND METHODS

28 processes were performed with Optia and 52 with Cobe. We compared volume reduction, RBCs depletion, and recovery of total nucleated cells (TNCs), mononuclear cells (MNCs), CD34+ and CD3+ cells in the final product. Hematopoietic engraftment was ascertained. We used Saphiro-Wilks and Kolmorgorov- Smirnov tests to test normality and Mann-Whitney's U test to compare means between both groups.

RESULTS

We found statistically significant differences favoring Optia versus Cobe in TNCs recovery (62% vs. 37%), CD34+ cell recovery (98 vs 84%), volume reduction (91 vs 84%), and RBCs depletion (99 vs. 97%), but not in processing time or time to engraftment.

CONCLUSION

Optia achieves high RBCs and volume depletion of BM, while providing excellent CD34+ recovery in clinical routine. Some parameters compare favorably with Cobe Spectra.

A comparison of two protocols for optimal red blood cell depletion using Sepax-2 device for ABO-major incompatible transplantation in adults

PURPOSE OF THE STUDY

In ABO-incompatible bone marrow transplantation, an efficient depletion of red blood cells (RBC) within the graft is mandatory to avoid adverse events in transplanted patients. Using non therapeutic products, we evaluated the substitution of the standard density gradient-based separation (DGBS) over Ficoll-Paque with the use of an automated procedure intended for buffy coat only (SmartRedux software) introducing modifications within the settings to achieve a drastic reduction of the initial volume of the product. Both methods were conducted on the Sepax-2 device.

SAMPLES AND METHODS

RBC depletion rates and CD34+ cells recoveries from eight procedures with SmartRedux software using "in-house" settings (method A) were compared to those obtained from four procedures using NeatCell software, an automated DGBS over Ficoll-Paque (method B).

RESULTS

Median erythrocyte depletion of 95,4% (92,7%-99,0%) and 99,8% (99,0%-99,9%) were observed using methods A and B, respectively. Median residual RBC volumes in the final product were 19 mL (4,4 mL-31,2 mL) and 0,7 mL (0,4 mL-4,7 mL), respectively (p = 0,014). CD34+ cells recoveries of 90,9% (62,7%-102,1%) and 78,4% (64,1%-86,2%) were achieved for methods A and B. Median platelet depletion was 16,6% (10%-42,7%) and 89,8% (88,5%-92,4%) using methods A and B, respectively (p = 0,004). Processing duration was shorter using method A (168 ± 29 min) than method B (295 ± 21 min) (p = 0,004).

CONCLUSION

Both methods achieved satisfactory erythrocyte depletion and CD34+ recovery. The use of Sepax-2 device in association with SmartRedux software could be extended to efficiently deplete RBC from large-volume BM in a raw instead of DGBS.

Erythrocyte depletion from bone marrow: performance evaluation after 50 clinical-scale depletions with Spectra Optia BMC

BACKGROUND

Red blood cell (RBC) depletion is a standard graft manipulation technique for ABO-incompatible bone marrow (BM) transplants. The BM processing module for Spectra Optia, "BMC", was previously introduced. We here report the largest series to date of routine quality data after performing 50 clinical-scale RBC-depletions.

METHODS

Fifty successive RBC-depletions from autologous (n = 5) and allogeneic (n = 45) BM transplants were performed with the Spectra Optia BMC apheresis suite. Product quality was assessed before and after processing for volume, RBC and leukocyte content; RBC-depletion and stem cell (CD34+ cells) recovery was calculated there from. Clinical engraftment data were collected from 26/45 allogeneic recipients.

RESULTS

Median RBC removal was 98.2% (range 90.8-99.1%), median CD34+ cell recovery was 93.6%, minimum recovery being 72%, total product volume was reduced to 7.5% (range 4.7-23.0%). Products engrafted with expected probability and kinetics. Performance indicators were stable over time.

DISCUSSION

Spectra Optia BMC is a robust and efficient technology for RBC-depletion and volume reduction of BM, providing near-complete RBC removal and excellent CD34+ cell recovery.