Umbilical cord blood processing with the Optipress II blood extractor.

Abstract

We have previously shown that UC blood (UCB) units can be volume-reduced manually, in a closed system, without major losses of nucleated and CD34(+) cells and without the addition of exogenous material. Our aim was to use an automated method for the separation of the UCB components using the Optipress II, extractor, with the 'buffy-coat' collection in a standardized volume. After centrifugation, the 51 UCB units were separated into the three blood components, plasma, buffy coat (BC) and red cells, using the Optipress II. The final volume of the BC fraction, rich in nucleated and progenitor CD34(+) cells, was set at 30 mL. The nucleated and CD34(+) cell content of the UCB collections and the resulting BC were evaluated. The UCB units were grouped according to the volume collected: Group I < 80 mL and Group II > or = 80 mL. Standardization of the BC at 30 mL resulted in significant volume reduction for both groups, with median values of 51% in Group I and 70% in Group II. The nucleated and CD34(+) cell recoveries in the BC from Group I were 88% and 99% respectively; for Group II they were 80% and 97%. This semi-automated method of volume reduction efficiently reduces low, as well as high volume UCB units, with good nucleated- and progenitor-cell yields. Being a closed system and free of external material, the risk of contamination is minimized. The resulting fractions are then available for validation studies of the unit, effectively fulfilling the main requisites for UCB banking.