Improved collection of mobilized CD34+ hematopoietic progenitor cells by anovel automated leukapheresis system

BACKGROUND: For simplification of blood cell transplantation, an automated apheresis system that exploits a dual-stage channel device for mononuclear cell (MNC) collection (AutoPBSC, designed for the COBE Spectral was studied . STUDY DESIGN AND METHODS:The automated default software (AutoPBSC-Default) and three software modifications of the harvest frequency during leukaphere sis, referred to as AutoPBSC-1.25, AutoPBSC-1.75, and AutoPBSC-2.75, were e valuated in comparison with the semiautomated Version 4.7 (V4.7) apheresis system in 119 leukapheresis procedures performed in 90 cancer patients trea ted with chemotherapy plus granulocyte-colony-stimulating factor. CD34+ cel l and platelet collection efficiency (CE); volume and cell composition of t he leukapheresis components; and patient platelet and red cell (RBC) loss d uring leukapheresis were measured. RESULTS:The majority of collection measures evaluated with the AutoPBSC com pared favorably to those obtained with the V4.7. CD34+ cell CE increased fr om 55 percent with V4.7 to 68 percent with the AutoPBSC-Default (p = 0.05). The AutoPBSC provided lower platelet contamination in the collected compon ent (1.18 x 10(11) vs. 2.26 x 10(11) with the V4.7; p<0.001). The volume of the AutoPBSG-Default component was significantly lower (67 vs. 180 mL with the V4.7; p<0.001).The MNC purity of the AutoPBSC component was greater (5 2 vs. 28% with the V4.7; p<0.001), and the RBC contamination lower (AutoPBS C, 0.53 x 10(11) vs. 1.04 x 10(11) with the V4.7; p<0.001). Modifications o f the AutoPBSC to increase the harvest frequency by 1.25-, 1.75-, and 2.75- fold resulted in increased CD34+ cell CE (77%, 75%, and 83%, respectively; p<0.001 in all cases), but also in reduced numbers of circulating platelets , higher platelet contamination of the component, and lower MNC purity than were seen with the AutoPBSC-Default. CONCLUSION:The AutoPBSC offers the following advantages over the V4.7 syste m: a) better CE of CD34+ cells; b) reduced collection of platelets; c) redu ced contamination of the leukapheresis component with granulocytes, platele ts, and RBCs; d) reduced component volume; and e) automation.