Debulking blood stem cell collections by density gradient centrifugation in a closed-vessel system.
BACKGROUND
Blood stem cells collected by apheresis are largely mononuclear cells in nature, so manipulation of blood stem-cell components frequently requires more time and reagents than for a marrow harvest. Reducing the nucleated cell number in mobilized blood stem-cell collections, while preserving hematopoietic progenitor content, would make such manipulations simpler and less costly, but only if debulking procedures were not complex.


METHODS
We evaluated separation of light-density cells and enrichment of CD34+ cells from mobilized peripheral blood stem-cell collections by density gradient centrifugation over buoyant density solution 60 (BDS 60) in a single, closed vessel.


RESULTS
Fifteen apheresis products from five normal volunteers and eight cancer patients contained 3.44 (range, 1.19-5.51) x 10(10) nucleated cells. Following processing and washing, there was a median 29% recovery of nucleated cells, 79% recovery of CD34+ cells, 2.49-fold enrichment of CD34+ cells, 0.96-log depletion of CD3+ cells, 0.48-log depletion of CD56+ cells, and 0.72-log depletion of CD19+ cells. Results of processing were affected by the variability in composition of the apheresis products. The enrichment of CD34+ cells varied by donor type, and there was a logarithmic relationship between the preprocessing percentage of CD19+ cells and the log reduction in CD19+ cells. Recovery of cells after thawing and washing was acceptable for processed cells cryopreserved at concentrations over the range of 0.01-1.5 x 10(8)/mL.


CONCLUSIONS
These results demonstrate a simple method by which an apheresis product of 1-5 x 10(10) cells can be debulked effectively in a single, closed vessel.
Przepiorka
D
D
Department of Blood and Marrow Transplantation, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Lu
J G
JG
Anderlini
P
P
Körbling
M
M
Donato
M
M
Champlin
R
R
Gee
A P
AP
van Vlasselaer
P
P
D000293:Adolescent; D000328:Adult; D018941:Antigens, CD19 / Q000032:analysis; D018952:Antigens, CD34 / Q000032:analysis; D001772:Blood Cell Count; D001781:Blood Component Removal; D017252:CD3 Complex / Q000032:analysis; D019002:CD56 Antigen / Q000032:analysis; D002469:Cell Separation / Q000295:instrumentation / Q000379:methods*; D002499:Centrifugation, Density Gradient / Q000295:instrumentation; D015925:Cryopreservation; D004867:Equipment Design; D005260:Female; D000069585:Filgrastim; D016179:Granulocyte Colony-Stimulating Factor / Q000627:therapeutic use; D019650:Hematopoietic Stem Cell Mobilization; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006412:Hematopoietic Stem Cells / Q000187:drug effects / Q000276:immunology / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins; D055815:Young Adult
D018941:Antigens, CD19; D018952:Antigens, CD34; D017252:CD3 Complex; D019002:CD56 Antigen; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D000069585:Filgrastim