Differential expression of CD73, CD86 and CD304 in normal vs. leukemic B-cell precursors and their utility as stable minimal residual disease markers in childhood B-cell precursor acute lymphoblastic leukemia

Background While it is known that CD123 is normally strongly expressed on plasmacytoid dendritic cells and completely absent on nucleated red blood cells, detailed information regarding CD123 expression in acute leukemia is scarce and, if available, hard to compare due to different methodologies. Methods CD123 expression was evaluated using standardized EuroFlow immunophenotyping in 139 pediatric AML, 316 adult AML, 193 pediatric BCP‐ALL, 69 adult BCP‐ALL, 101 pediatric T‐ALL, and 28 adult T‐ALL patients. Paired diagnosis‐relapse samples were available for 57 AML and 19 BCP‐ALL patients. Leukemic stem cell (LSC) data was available for 32 pediatric AML patients. CD123 expression was evaluated based on mean fluorescence intensity, median fluorescence intensity, and percentage CD123 positive cells. Results EuroFlow panels were stable over time and between laboratories. CD123 was expressed in the majority of AML and BCP‐ALL patients, but absent in most T‐ALL patients. Within AML, CD123 expression was lower in erythroid/megakaryocytic leukemia, higher in NPM1 mutated and FLT3‐ITD mutated leukemia, and comparable between LSC and leukemic blasts. Within BCP‐ALL, CD123 expression was higher in patients with (high) hyperdiploid karyotypes and the BCR‐ABL fusion gene. Interestingly, CD123 expression was increased in BCP‐ALL relapses while highly variable in AML relapses (compared to CD123 expression at diagnosis). Conclusions Authors evaluated CD123 expression in a large cohort of acute leukemia patients, based on standardized and reproducible methodology. Our results may facilitate stratification of patients most likely to respond to CD123 targeted therapies and serve as reference for CD123 expression (in health and disease). © 2018 The Authors. Cytometry Part B: Clinical Cytometry published by Wiley Periodicals, Inc. on behalf of International Clinical Cytometry Society.

Section: Conclusion and Discussionmentioning

confidence: 99%

CD123 expression levels in 846 acute leukemia patients based on standardized immunophenotyping

Bras

Haas

Stigt

et al. 2018

“…With the improvements in induction therapy for pediatric B lymphoblastic leukemia, attention is gradually shifting to later time points from therapy, End of Consolidation in particular, in order to identify patients who have had inadequate response to initial therapy and who might benefit from one of multiple novel treatments now available, for example, anti‐CD19 or anti‐CD22 therapy. To this end, new reagents have been identified that may allow improved discrimination of hematogones from residual leukemia , a few of which have been demonstrated to be of potential value in defined reagent combinations tested on patient cohorts , these include CD49f , CD81 , CD123 , CD73 (see Fig. ), CD86 , and CD304 .…”

Section: Minimal/measurable Residual Disease Detectionmentioning

confidence: 99%

“…To this end, new reagents have been identified that may allow improved discrimination of hematogones from residual leukemia , a few of which have been demonstrated to be of potential value in defined reagent combinations tested on patient cohorts , these include CD49f , CD81 , CD123 , CD73 (see Fig. ), CD86 , and CD304 . To date, testing of these reagents has been performed largely at diagnosis and early timepoints after therapy (up to End of Induction).…”

Section: Minimal/measurable Residual Disease Detectionmentioning

confidence: 99%

Applications of Flow Cytometric Immunophenotyping in the Diagnosis and Posttreatment Monitoring of B and T Lymphoblastic Leukemia/Lymphoma

DiGiuseppe

Wood

2019

In this review, we discuss applications of flow cytometric immunophenotyping (FCI) in the diagnostic evaluation and posttreatment monitoring of B and T lymphoblastic leukemia/lymphoma. We describe practical approaches to FCI at the time of diagnosis, with an emphasis on blast identification, lineage assignment, and distinction of B and T lymphoblastic leukemia/lymphoma from their morphologic and immunophenotypic mimics. We further review flow cytometric assays for the detection of minimal or measurable residual disease (MRD) after treatment, and illustrate both standard approaches, and newer strategies for improving sensitivity and circumventing the loss of immunophenotypic targets after immunotherapy. © 2019 International Clinical Cytometry Society

“…One interesting point is our demonstration that using additional LAIP markers to upgrade to an eight‐color tube led to detection of low MRD level, with strong correlation when compared to liquid format tube. We tested several potential blast markers, such as lineage aberrant markers (CD33 or CD13), or some more recently described aberrant markers for BCP‐ALL such as CD49f, CD66c, or CD123 (; ). These additional markers allowed quite low detection threshold, with comparable detection performance for dried versus liquid tube.…”

Section: Discussionmentioning

confidence: 99%

Detection of Minimal Residual Disease in B Cell Acute Lymphoblastic Leukemia Using an Eight‐Color Tube with Dried Antibody Reagents

Bouriche

Bernot

Nivaggioni

et al. 2019

Background Flow cytometry is a powerful tool for the detection of minimal residual disease (MRD) of B cell precursor acute lymphoblastic leukemia (BCP‐ALL) patients. However, the staining process and the choice of antibodies rely on laboratory expertise and may be source of variability or technical errors. Recently, Beckman Coulter commercialized a ready to use tube with dried format reagents for BCP‐ALL MRD detection. The aim of this study is to evaluate the applicability of this tube and to compare it to a conventional (liquid format reagents) method. Methods Thirty‐one samples from B ALL patients were analyzed: 19 bone marrow (BM) aspirations, 10 peripheral blood (PB) samples and 2 cerebrospinal fluids at different stages of the follow‐up. In addition, we tested 5 bone marrow samples mixed into non‐pathological (control) bone marrow. The dried format tube included seven antibodies: CD45Kro, CD58FITC, CD34ECD, CD10PC5.5, CD19PC7, CD38AA700, CD20AA750, with possibility of additional antibodies for blast markers identified at diagnosis. For comparison, a liquid format tube was prepared, and considered as the reference. Results This tube was validated for daily routine laboratory, with satisfying qualitative (MRD + or MRD−) and quantitative (MRD percentages) correlation with the reference tube. Conclusion With this single dried format tube, we showed interesting results for BCP‐ALL MRD detection in the aim of standardization and reliable interlaboratory results. It allows accurate MRD detection including low levels (10–4), and offers possibility to increase performance (supplementary antibody) within a preestablished effective antibody panel for BCP‐ALL MRD. © 2018 International Clinical Cytometry Society