Immunomagnetic selection of CD34+ cells: factors influencing component purity and yield.
BACKGROUND
In immunomagnetic selection of CD34+ cells from HPC transplants, not all factors that affect yield and purity of CD34+ cells are known.


METHODS
Forty-three consecutive procedures of immunomagnetic selection of CD34+ cells from peripheral blood HPCs and bone marrow harvests (autologous harvests, n = 27; allogeneic harvests; n=16) were performed by use of a cell selection system (Isolex 300i, Baxter Immunotherapy). The composition of the starting component and the subsets of CD34+ cells were analyzed for correlation with the yield and purity of the final component.


RESULTS
The mean purity of the final components was 84.3 percent (range, 27-99%), and the mean yield was 51.4 percent (range, 9.4-80. 4%). Partial regression analysis showed that, among the factors correlating with purity and/or yield, the RBC volume in the starting fraction had the highest predictive impact on the purity and yield of CD34+ cells, even after the exclusion of procedures using bone marrow harvests as an HPC source (beta coefficient, -0.704; p = 0. 001).


CONCLUSIONS
The use of the Isolex 300i system allows efficient recovery of CD34+ cells in routine selection procedures. The volume of RBCs in the starting component should be minimized to ensure a high yield and purity of the final component.
Hildebrandt
M
M
Departments of Internal Medicine (Blood Bank) and Pediatrics, Charité, Campus Virchow Klinikum, Humboldt University, Berlin, Germany. hildebra@charite.de
Serke
S
S
Meyer
O
O
Ebell
W
W
Salama
A
A
D018952:Antigens, CD34 / Q000097:blood*; D006400:Hematocrit; D006801:Humans; D018189:Immunomagnetic Separation / Q000379:methods; D016014:Linear Models; D009447:Neuroblastoma / Q000097:blood; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000097:blood; D012512:Sarcoma, Ewing / Q000097:blood
D018952:Antigens, CD34