Isolation of CD34+ progenitor cells from peripheral blood by use of an automated immunomagnetic selection system: factors affecting the results

• Published in: Transfusion (Philadelphia, Pa.) Vol. 40; no. 1; pp. 35 - 43
• Main Authors: Martín‐Henao, G.A., Picón, M., Amill, B., Querol, S., González, J.R., Martínez, C., Martino, R., Ferrá, C., Brunet, S., Grañena, A., Sierra, J., García, J.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Inc 01.01.2000; Blackwell Publishing
• Subjects: 7‐AAD = 7‐aminoactinomycin‐D; Adult; Aged; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Antigens, CD34 - blood; Biological and medical sciences; Bone marrow, stem cells transplantation. Graft versus host reaction; CFU = colony‐forming units; Colony-Forming Units Assay; Cryopreservation; CSF = colony‐stimulating factor; DNase = deoxyribonuclease I; Female; FITC = fluorescein isothiocyanate; GAM = goat anti‐mouse; GM = granulocyte; Granulocytes - transplantation; Hematopoietic Stem Cells - immunology; Humans; IB(s) = immunomagnetic bead(s); Immunomagnetic Separation - methods; LK = leukapheresis; Lymphocyte Depletion; Male; Medical sciences; MFI = mean fluorescence intensity; Middle Aged; MoAb(s) = monoclonal antibody(ies); NC(s) = nucleated cell(s); PBPC(s) = peripheral blood progenitor cell(s); PE = phycoerythrin; PR = peptide release reagent; rHu = recombinant human; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Blood product; Human; Immunomagnetic method; Separation; Automatic selection; Hematopoietic cell; Homograft; B-Lymphocyte; Blood; Cytometry; Autograft; T-Lymphocyte; Graft; Evolution; Technique; Progenitor cell
• ISSN: 0041-1132; 1537-2995
• DOI: 10.1046/j.1537-2995.2000.40010035.x

BACKGROUND: The isolation of CD34+ cells from mobilized peripheral blood is being increasingly used in the setting of allogeneic or autologous hematopoietic cell transplantation. Investigation of variables that may influence the effectiveness of CD34+ cell selection is of interest. STUDY DESIGN AND METHODS: Fifty‐one CD34+ cell selections from peripheral blood progenitor cells (PBPCs) (39 allogeneic and 12 autologous) were performed using a magnetic cell separator (Isolex 300i, Baxter), including version 2.0 software. The results obtained were analyzed for different processing variables. The feasibility of transplanting these isolated CD34+ cells was also analyzed. RESULTS: The isolated CD34+ cell fraction had a median purity of 88.9 percent (range, 47.8‐98.3). The median recovery of CD34+ cells was 45.1 percent (13.8‐76.2), and the median colony‐forming unit– granulocyte‐macrophage (CFU–GM) content was 17.2 percent (0.8‐58.6). Logarithms of T‐ and B‐cell depletion had median values of 3.7 and 2.8, respectively. The version 2.0 software of the Isolex 300i gave a higher CD34+ cell recovery in the enriched cell fraction (median 57.8%) than did version 1.11 (39.4%) or 1.12 (44.4%) (p = 0.01). The use of recombinant human deoxyribonuclease I during cell processing yielded more CD34+ cells (53% vs. 41%, p = 0.01) and higher purity (92.8% vs. 87%, p = 0.03). There was a correlation between the percentage of CD34+ cells labeled with the monoclonal antibody 8G12 clone and the percentage of CD34+ cells labeled with the monoclonal antibody used during the processing technique (9C5 clone) in the initial, enriched, and depleted CD34+ cell fractions (R2 = 0.95; 0.92; 0.78, p< 0.005, respectively). Median times for recovering >0.5 × 109 per L of granulocytes and >20 × 109 per L of platelets were 13 and 16 days in the allograft patients and 13 and 14 days in the autograft patients. CONCLUSION: CD34+ cells can be highly and effectively isolated from allogeneic and autologous grafts by use of this automated technique, with a high grade of T‐ and B‐cell depletion. These purified CD34+ cell components can engraft normally.