Human UC-blood banking: impact of blood volume, cell separation and cryopreservation on leukocyte and CD34(+) cell recovery.
BACKGROUND
UC blood represents an increasingly useful source of hematopoietic stem cells for BMT, although, currently, low cell numbers generally limit its use to pediatric patients. We have determined parameters that influence the recovery of viable cells during processing and cryopreservation, in an effort to set guidelines for determining whether a sample will yield sufficient cells to be of use in the transplant setting.


METHODS
UC blood was collected from donors from January 1996 to December 1999. Volume was reduced using Ficoll, followed by cryopreservation under liquid nitrogen. Total leukocyte and CD34(+)-cell counts were determined prior to processing and a subset of samples was also assessed post-processing and post-cryopreservation.


RESULTS
Outcomes for 3816 samples were analyzed to determine the correlation between cell number, cell type, volume, and time between collection and processing. A positive relationship was observed between volume and cell number for both leukocytes and the CD34(+) cells. This correlation allowed us to determine the number of leukocytes and CD34(+) cells expected from a sample based on volume, and to set guidelines for determining the practicality of storing any given sample prior to processing and cryopreservation.


CONCLUSIONS
Measuring blood volume gives a very useful indication of the total leukocyte and CD34(+) cell number. The majority (75%) of cord-blood samples contain sufficient leukocytes for a pediatric transplant, and the number of cells available can be determined prior to processing by measuring blood volume.
Rogers
I
I
Division of Reproductive Sciences, Department of Obstetrics and Gynecology, The University of Toronto, Toronto, Ontario, Canada.
Sutherland
Holt
D
D
Macpate
F
F
Lains
A
A
Hollowell
S
S
Cruickshank
B
B
Casper
R F
RF
D018952:Antigens, CD34 / Q000276:immunology*; D000094902:Blood Banking / Q000379:methods*; D001810:Blood Volume / Q000502:physiology*; D002170:Canada; D002452:Cell Count; D002469:Cell Separation / Q000379:methods*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents; D005260:Female; D005312:Fetal Blood / Q000166:cytology* / Q000187:drug effects; D005434:Flow Cytometry; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn; D007962:Leukocytes / Q000166:cytology* / Q000187:drug effects; D011247:Pregnancy; D013997:Time Factors
D018952:Antigens, CD34; D003451:Cryoprotective Agents