PERIPHERAL-BLOOD STEM-CELL COLLECTION WITH A BLOOD-CELL SEPARATOR

Forty-three patients with malignant nonmyeloid diseases underwent peripheral blood stem cell collections on an apheresis system (Spectra, COBE BCT, Lakewood, CO). Collections took place during the white cell (WBC) recovery phase following conditioning chemotherapy. One hundred two procedures were done after chemotherapy alone, and 72 procedures after chemotherapy plus granulocyte-colony-stimulating factor(G-CSF). Four centrifugal separation factors were tested. One and one-half patient blood volumes were processed in each procedure. The mean volume of the collected component was 158 +/- 16 mL. After chemotherapy alone, the procedures provided a mean of 0.8 x 10(8) WBCs per kg and 2.3 x 10(4) colony-forming units-granulocyte macrophage (CFU-GM) per kg of recipient body weight. The mononuclear cell percentage in the components increased with the centrifugal separation factor from 85 to 96 percent. In parallel, platelet contamination increased from 2.1 to 3.8 x 10(11). The collect hematocrit ranged from 1.0 to 2.5 percent (0.01-0.025). The collection efficiency for mononuclear cells and CFU-GM also increased with the centrifugal separation factors from 52 to 70 percent for mononuclear cells and from 55 to 68 percent for CFU-GM. Collections performed after G-CSF-stimulated mobilization were characterized by a higher neutrophil contamination independent of centrifugal separation factor, which gave a mean mononuclear cell percentage of 64 percent in the collected component. The average yield for these procedures was 2 x 10(8) WBCs per kg and 28 x 10(4) CFU-GM per kg. The collection efficiency for mononuclear cells Increased with the separation factor from 43 to 77 percent. The collection efficiency for CFU-GM was greater than 100 percent.