Bi-phasic CD34+cell mobilization of a syngeneic donor during prolonged G-CSF delivery

Background G-CSF administration over 10 days and neutrophil cytapheresis ha ve been reported in the literature, but the kinetics of CD34(+) cells ii? t his situation is unclear Case. A 42-year-old female underwent syngeneic transplantation for metastat ic bl-east cancer: The recipient was in critical condition peri-transplant, therefore the donor received G-CSF for 13 days, during which eight cytaphe reses for both PBPC and neutrophils were performed. Two peaks in CD34(+) ce lls we.e noted; the first on Day 5 and the second on Days 10-13 of G-CSF ad ministration; a total of 11.6 x 10(6)/kg CD34(+) cells and 38.11 x 10(8)/kg neutrophils were infused. The recipient's ANC exceeded 0.1 x 10(9)/L on Da y +3. Discussion To our knowledge, this is the longest reported cytapheresis of C D34(+) cells from a normal donor: The bi-phasic pattern in the cytapheresis product is also of interest. It is an unusual pattern that suggests a prof ound and complicated alteration in the marrow progenitor cell pool. If subs tantiated, this finding may offer an alternative cytapheresis schedule for donors.