Analysis of Hematopoietic Cell Transplants Using Plasma-Depleted Cord Blood Products That Are Not Red Blood Cell Reduced

Abstract 

Limited cell dose hampers wider use of cord blood transplantation (CBT). By depleting plasma but not RBC during processing, nucleated cell (NC) loss is reduced to <0.1% which increases significantly the proportion of high cell dose products—3-fold for products with NC ≥200 × 10⁷. Clinical outcome for plasma depleted (PD) CBT was previously unavailable. A retrospective audited analysis was performed on 118 PD CBT, with mean and median NC doses of 7.6 × 10⁷/kg and 5.6 × 10⁷/kg, respectively, for this mostly pediatric population. The median times to engraftment and engraftment rates for ANC 500 and platelet 20K were 22 and 50 days, respectively, and 90% ± 3% and 77% ± 5%, respectively. The incidences of grade III-IV acute graft-versus-host disease (aGVHD) and extensive chronic GVHD (cGVHD) were 13% ± 4% and 17% ± 6%, respectively. Relapse rate for malignancies was 25% ± 6% and 100-day treatment-related mortality (TRM) was 16% ± 3%. With a median follow-up of 557 days, the 1-year overall survival and relapse-free survival are 65% ± 5% and 51% ± 6%, respectively. These results demonstrate that PD CBT is safe and effective, and that eliminating RBC reduction or depletion improves cell recovery during CB processing, resulting in a larger proportion of the inventory with high NC number.

Key Words: Cord blood transplantation, Cord blood banking, Plasma depletion, Cord blood processing, Volume reduction, Postthaw wash