Collection of two peripheral blood stem cell concentrates from healthy donors

When peripheral blood stem cell (PBSC) concentrates are used for allogeneic transplants, two or more apheresis procedures must often be performed. To determine how many cells could be collected from healthy people by two back -to-back apheresis procedures and what effect these collections would have on donors, we gave 19 healthy people 5 mu g kg(-1) day(-1) and 21 people 10 mu g kg(-1) day(-1) of granulocyte colony stimulating factor, filgrastim, for 5 days. We then collected two PBSC concentrates, one on day 5 and one o n day 6. A third group of six people was given filgrastim 10 mu g kg(-1) da y(-1) for 5 days but had no PBSC concentrates collected. PBSC concentrate c ell counts and donor cell counts, symptoms, and blood chemistries were asse ssed for up to 1 year. On day 5, three times more CD34+ cells were collected from donors given 10 mu g kg(-1) day(-1) than those given 5 mu g kg(-1) day(-1) (P = 0.009) but on day 6 the quantity of cells collected was the same (P = 0.23). The total number of CD34+ cells collected was two times greater in donors given the higher dose of filgrastim (median = 579 x 10(6); range = 174-1639 x 10(6) c ompared to 237 x 10(6); 103-1670 x 10(6) P = 0.061), Platelet counts fell after each PBSC concentrate collection, but there were no differences between the two groups of donors in platelet counts measure d immediately after each collection. The platelet counts also fell in peopl e who did not donate PBSC concentrates. The lowest counts in all three grou ps of people also occurred on day 10, In PBSC donors given 10 mu g kg(-1) day(-1) of filgrastim the absolute neut rophil count (ANC) fell below premobilization counts an day 14, In donors g iven 5 mu g kg(-1) day(-1) the ANC fell below premobilization counts on day s 21, 28 and 49. CD34+ cell counts were significantly lower than premobiliz ation counts on days 14 and 28 in donors given 10 mu g kg(-1) day(-1) of fi lgrastim and on day 14 in those given 5 mu g kg(-1) day(-1). No decrease in neutrophil or CD34+ cell counts occurred after filgrastim was given in the people who did not donate PBSC concentrates. The incidence of symptoms was similar in both groups of PBSC concentrate do nors, except that those given 10 mu g kg(-1) day(-1) were more than twice a s likely to experience myalgias as those receiving the lower dose (P = 0.02 9). Several blood chemistries changed. Levels of alkaline phosphatase, LDH, SGPT, SGOT, uric acid and sodium increased. Levels of bilirubin, total pro tein, potassium, calcium and chloride decreased. In conclusion, twice as many CD34+ cells were collected from donors given 1 0 mu g kg(-1) day(-1) of filgrastim. Platelet, neutrophil and CD34+ cell co unts fell after the PBSC concentrate collections. The fall in platelet coun ts was due to both the collection and the administration of filgrastim. The falls in neutrophil and CD34+ cell counts were due to the loss of haematpo ietic progenitor cells in the PBSC concentrates. Allogeneic PBSC concentrat e donors should be given 10 mu g kg(-1) day(-1) of filgrastim, and if possi ble only one component should be collected in order to avoid thrombocytopen ia.