Stem cell collection using the Dideco Excel continuous flow blood cell separator: parameters for optimal stem cell collection timing

This study evaluates stem cell collection procedures performed with the Did eco Excel blood cell separator with particular attention given to yields an d separator collection efficiencies. Patients' blood precounts and yield pa rameters related to the harvest capacity of the collection system were inve stigated. Fifty-five collection procedures were analyzed in 32 patients suf fering from hematological malignancies and solid tumors and mobilized with chemotherapy plus G-CSF. The median blood volume processed in each procedur e was 15.8 liters (12-19.750), with a blood flow rate of 70 ml/min. Patient s had the following median blood precount valuer NC 7.81x10(9)/L, CD34+ cel ls 49.08x10(3)/ml. Leukapheresis procedures gave the following yields: NC 1 4.95x10(9) MNC 10.83x10(9), CD34+ cells 4.37x10(6); yields/kg, NC 0.21x10(9 )kg, MNC 0.15x10(9)/kg CD34+ cells 4.26x10(6)/kg. Procedures show the follo wing collection efficiencies. NC 10.79%, IV]NC 29.06%, CD34+ 42.33%; PLT 26 .5%. The RBC (red blood cell) contamination of the product was (median valu e) 20.9 mi for each procedure, and for platelets I. 76x10(11) per procedure . The CD34+ cell precounts strongly correlated with the CD34+ yields/kg (r= 0.82. p=0.000). Furthermore the NC and MNC precounts correlated with the CD 34+ yields/kg but only the MNC precount correlation is notable (r=0.57, p=0 .000). The logistic regression analysis shows that CD34+ (p=0.008) but not NC (po=0.14), MNC (p=0.09), or PLT (p=0.53) precounts significantly influen ced the collection of a sufficient dose of CD34+ cells for transplantation (greater than or equal to2.5x10(6)/kg). Eleven of the thirty-two patients h ave been transplanted till now, and all had a prompt and lasting trilineage engraftment NC >1x10(9)/L on day 12 (10-17). Our data show that the collec tion system analyzed in this report is able to collect large amounts of pro genitor cells, harvesting greater than or equal to2.5x10(6)/kg CD34+ cells with a single procedure in 68.8% of patients and assuring complete recovery after stem cell transplantation.