Immunophenotypic characteristics distinguish leukemic stem cells (LSCs) from healthy hematopoietic stem cells (HSCs) in adults with acute myeloid leukemia (AML). However, immunophenotypic stem cell features in pediatric AML have received little attention. For a study, researchers used a 15-color flow cytometry technique to examine the expression of eight abnormal surface markers and BCL-2 on CD34+CD38− bone marrow stem cells from 38 pediatric patients with AML and seven non-leukemic, age-matched controls. In addition, Clonality was also studied using genetic analysis of immunophenotypically aberrant stem cells from six individuals.
About 50 aberrant marker positive (non-HSC-like) subgroups with 41 distinct immunophenotypic characteristics were identified. The most frequently expressed markers were CD123, CLEC12A, and IL1RAP. IL1RAP, CD93, and CD25 were not limited to stem cells harboring leukemia-associated mutations. BCL-2 expression differed across specified cytogenetic groupings. Surprisingly, BCL-2 overexpression was seen exclusively in immunophenotypically aberrant non-HSC-like fractions. They discovered significant immunophenotypic variability within the stem cell compartments of juvenile patients with AML. Furthermore, several abnormal markers utilized in adults appeared inappropriate for detecting leukemia-representing stem cells in pediatric patients, emphasizing that concluding adult research should be done with caution.
Reference:onlinelibrary.wiley.com/doi/10.1111/bjh.18094
