Cord blood banking: volume reduction of cord blood units using a semi-automated closed system

Clinical evidence indicates that placental/umbilical cord blood (CB) is an alternative source of haematopoietic stem cells for bone marrow reconstitut ion, To establish a CB bank large panels of frozen, HLA-typed CB units need to be stored. Cryopreserved, unprocessed CB units require vast storage spa ce. This study describes a method, using the Optipress II Automated Blood C omponent Extractor (Opti II) from Baxter Healthcare Corporation, to reduce the volume of the CB collection, preserving the quantity and quality of the progenitor cells, in a closed system. The CB collection was transferred to a triple bag system, centrifuged to produce a buffy coat layer and process ed using a standard Opti II protocol to separate the whole blood into three components: plasma, buffy coat and buffy coat-depleted red cell concentrat e, The buffy coat volume was standardised to 25 ml; mean reduced volume of 24.5 ml (s.d. 1.5 ml) with 53% red cell depletion. Good recovery of cells w as observed: 92%, 98%, 96% and 106% recovery of nucleated, mononuclear, CD3 4(+) and total colony-forming cells, respectively, Using this method for pr ocessing CB units reduces storage requirement by two-thirds but preserves t he quantity and quality of the progenitor cells.