title: Flow cytometric analysis of BCL-2 can distinguish small numbers of acute lymphoblastic leukaemia cells from B-cell precursors.
abstract: Flow cytometric identification of small numbers of precursor B-cell acute lymphoblastic leukaemia (B-ALL) cells in post-treatment marrow specimens could benefit from the identification of additional, easily detectable markers that could be used in most cases. In this study, we evaluate whether bcl-2 expression quantified by four-colour flow cytometry can be effectively used to discriminate precursor B-ALL blasts from normal B-cell precursors (haematogones) and function as a leukaemia-specific marker. Levels of bcl-2 in the 22 precursor B-ALL cases studied were found to be significantly higher (over sixfold higher on average) than those present in haematogone populations from 22 control marrow specimens. Higher relative levels of bcl-2 expression in the B-ALL cases were maintained with respect to both immature CD34+ and more mature CD34- haematogone subsets, and appeared stable. Dilutional studies indicated that multiparameter flow cytometry analysis using bcl-2 could identify precursor B-ALL blasts representing as few as 1% of CD19+ cells or 0.01% of total leucocytes in bone marrow specimens containing substantial numbers of haematogones. This study suggests that bcl-2 may be an important marker for flow cytometric detection and quantification of small numbers of residual precursor B-ALL cells in bone marrow specimens.
authors.affiliation: ARUP Institute of Clinical and Experimental Pathology, University of Utah, Salt Lake City, UT 84132, USA.
authors.forename: Leah
authors.initials: L
authors.lastname: Hartung
authors.forename: David W
authors.initials: DW
authors.lastname: Bahler
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001402:B-Lymphocytes / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002051:Burkitt Lymphoma / Q000175:diagnosis* / Q000473:pathology; D002454:Cell Differentiation; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism; D018365:Neoplasm, Residual; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D019253:Proto-Oncogene Proteins c-bcl-2