Effect of high nucleated cell concentration on product viability and hematopoietic recovery in autologous transplantation

Background: Administering lower total product volumes with high nucleated cell (NC) concentrations may have the potential benefit of decreasing volume- and dimethyl sulfoxide (DMSO)-related patient complications, while maximizing the laboratory's freezer storage capacity. Our study is a retrospective investigation of the effect of HPC(A) products with cell concentrations greater than 3 × 10⁸ NC/mL on clinical and product outcomes in patients undergoing autologous peripheral blood stem cell (PBSC) transplantation.

Study design and methods: A total of 113 consecutive patients with hematological malignancies who underwent autologous PBSC transplantation were included in this retrospective analysis. The primary outcomes were days to initial absolute neutrophil count (ANC) recovery and initial platelet recovery. The secondary outcomes included the storage duration, segment thaw viability, and dose of viable CD34+ cells/kg administered.

Results: Of 92 patients and 176 apheresis procedures, 81 patients received HPC(A) products with high NC concentration (4.1 × 10⁸ NC/mL), and 11 patients received low NC concentration products (2.4 × 10⁸ NC/mL). There were no observed differences in clinical outcomes with respect to ANC recovery (14 vs. 14 vs. 12 days) and platelet recovery (16 vs. 16 vs. 15 days) when very high NC (5.2 × 10⁸ NC/mL) and high NC (4.1 × 10⁸ NC/mL) groups were compared to the low NC group (2.4 × 10⁸ NC/mL).

Conclusion: Our retrospective investigation provides further supporting evidence that HPC(A) products with cell concentration greater than 3 × 10⁸ NC/mL did not show detrimental effects on the clinical outcomes in patients undergoing autologous PBSC transplantation.