Pedro Marin, Lluis Jover and Jordi Petriz Pages 163 - 171 ( 9 )
Background: In the absence of a gold standard for hematopoietic progenitor counting, the intra-laboratory variation between commonly used strategies for progenitor assessment was compared. Methods and Materials: We used a pool of FITC-conjugated monoclonal antibodies (CD14, CD11b) and PE-CD34 to facilitate CD34 counting, excluding CD14+/CD11b+ bright cells. We compared this protocol with other common methodologies, such as the single-staining approach, known as the Milan method, and the ISHAGE multiparameter method. Results: We show that the CD14/CD11b protocol is a valid approach to progenitor cell counting. Though different methods give different results for progenitor cell counting, Lin’s coefficient shows high concordance among flow cytometry counts but a substantial difference with colony- forming unit counts. Both the ISHAGE and CD14/CD11b protocol give higher counts than the Milan method. Moreover, on revising the ISHAGE analysis, we described a rare population of cells with the CD34+CD45neg phenotype, which could have an impact in CD34 counting. Conclusions: We have designed a valid alternative approach for hematopoietic progenitor cell counting, and we show that different methods give different results.
CD34, CD45, flow cytometry, ISHAGE, Milan, quality control, Hematopoietic Progenitor Cell Counting, monoclonal antibodies
Laboratori 207, Vall d'Hebron Institut de Recerca, Pº Vall d'Hebron 119-129, 08035 Barcelona, Spain.