CD34(+) selection of hematopoietic blood cell collections and autotransplantation in lymphoma: overnight storage of cells at 4 degrees C does not affect outcome

The purpose of this study was to investigate whether storing mobilized peri pheral blood progenitor cell (PBPC) collections overnight before CD34(+) se lection may delay platelet count recovery after high-dose chemotherapy and CD34(+)-enriched PBPC re-infusion. Lymphoma patients underwent PBPC mobiliz ation with cyclophosphamide 4 g/m(2) i.v. and G-CSF 10 mu g/kg/day subcutan eously. Patients were prospectively randomized to have each PBPC collection enriched for CD34(+) cells with the CellPro CEPRATE SC System either immed iately or after overnight storage at 4 degrees C, Thirty-four patients were randomized to overnight storage and 34 to immediate processing of PBPC; 15 were excluded from analysis due to tumor progression or inadequate CD34(+) cell mobilization, PBPC from 23 patients were stored overnight, while 30 s ubjects underwent immediate CD34(+) selection and cryopreservation, Median yield of CD34(+) enrichment was 43.6% in the immediate processing group com pared to 39.1% in the overnight storage group (P = 0.339). Neutrophil recov ery >500 x 10(9)/l occurred a median of 11 days (range 9-16 days) in the ov ernight storage group compared to 10.5 days (range 9-21 days) in the immedi ate processing group (P = 0.421). Median day to platelet transfusion indepe ndence was 13 (range 7-43) days in the overnight storage group vs 13.5 (ran ge 8-35) days in those assigned to immediate processing (P = 0.933). We con clude that storage of PBPC overnight at 4 degrees C allows pooling of conse cutive-day collections resulting in decreased costs and processing time wit hout compromising neutrophil and platelet engraftment after infusion of CD3 4(+)-selected progenitor cells.