In:
British Journal of Haematology, Wiley, Vol. 178, No. 2 ( 2017-07), p. 257-266
Abstract:
Flow cytometric detection of minimal residual disease ( MRD ) in children with B‐cell precursor acute lymphoblastic leukaemia ( BCP ‐ ALL ) requires immunophenotypic discrimination between residual leukaemic cells and B‐cell precursors ( BCP s) which regenerate during therapy intervals. In this study, EuroFlow‐based 8‐colour flow cytometry and innovative analysis tools were used to first characterize the immunophenotypic maturation of normal BCP s in bone marrow ( BM ) from healthy children, resulting in a continuous multiparametric pathway including transition stages. This pathway was subsequently used as a reference to characterize the immunophenotypic maturation of regenerating BCP s in BM from children treated for BCP ‐ ALL . We identified pre‐B‐I cells that expressed low or dim CD34 levels, in contrast to the classical CD34 high pre‐B‐I cell immunophenotype. These CD34 −dim pre‐B‐I cells were relatively abundant in regenerating BM (11–85% within pre‐B‐I subset), while hardly present in healthy control BM (9–13% within pre‐B‐I subset; P = 0·0037). Furthermore, we showed that some of the BCP ‐ ALL diagnosis immunophenotypes (23%) overlapped with CD34 −dim pre‐B‐I cells. Our results indicate that newly identified CD34 −dim pre‐B‐I cells can be mistaken for residual BCP ‐ ALL cells, potentially resulting in false‐positive MRD outcomes. Therefore, regenerating BM , in which CD34 −dim pre‐B‐I cells are relatively abundant, should be used as reference frame in flow cytometric MRD measurements.
Type of Medium:
Online Resource
ISSN:
0007-1048
,
1365-2141
DOI:
10.1111/bjh.2017.178.issue-2
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
1475751-5
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