title: Number of viable CD34(+) cells reinfused predicts engraftment in autologous hematopoietic stem cell transplantation.
abstract: Reduced CD34(+) cell viability due to cryopreservation has unknown effects on subsequent hematopoietic engraftment in autologous transplantation. Thirty-six consecutive autologous peripheral stem cell collections were analyzed for absolute viable CD34(+) cell numbers at the time of stem cell collection and prior to re-infusion. Viable CD34(+) cells were enumerated using single platform flow cytometry and the molecular exclusion dye 7-amino actinomycin D. The median number of viable CD34(+) cells was 3.6 x 10(6)/kg at the time of harvest and 2.0 x 10(6)/kg after thawing. When viable CD34(+)cells enumerated after thawing were <2.0, 2.0-5.0, or >5.0 x 10(6)/kg, the median time to platelet engraftment was 17, 12 and 10 days, respectively (P < 0.05 for comparison of the group with <2.0 x 10(6)/kg and the other two groups), and the median time to neutrophil engraftment was 13, 14 and 12 days, respectively (P = NS). A minimum of 2.0 x 10(6) CD34(+) cells/kg was harvested in 33 of 36 patients (92%) but only 19 of 36 (52%) patients met this threshold at the time of reinfusion. The reduced numbers of viable CD34(+) cells measured prior to re-infusion is associated with time to platelet engraftment and may be useful in monitoring stem cell loss during processing and identifying patients at risk of graft failure.
authors.affiliation: Division of Hematology, University of Western Ontario, London, Ontario, Canada.
authors.forename: D S
authors.initials: DS
authors.lastname: Allan
authors.forename: M
authors.initials: M
authors.lastname: Keeney
authors.forename: K
authors.initials: K
authors.lastname: Howson-Jan
authors.forename: J
authors.initials: J
authors.lastname: Popma
authors.forename: K
authors.initials: K
authors.lastname: Weir
authors.forename: M
authors.initials: M
authors.lastname: Bhatia
authors.forename: D R
authors.initials: DR
authors.lastname: Sutherland
authors.forename: I H
authors.initials: IH
authors.lastname: Chin-Yee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018952:Antigens, CD34 / Q000032:analysis*; D002452:Cell Count; D002470:Cell Survival; D015925:Cryopreservation / Q000592:standards; D006085:Graft Survival; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods / Q000592:standards*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology; D006801:Humans; D007700:Kinetics; D008875:Middle Aged; D009369:Neoplasms / Q000628:therapy; D036102:Peripheral Blood Stem Cell Transplantation / Q000379:methods / Q000592:standards; D011379:Prognosis; D011446:Prospective Studies; D013048:Specimen Handling; D014182:Transplantation, Autologous / Q000379:methods / Q000592:standards
chemical_list: D018952:Antigens, CD34