[Detection of Minimal Residual Disease in Acute Myeloid Leukemia by Multi-color Flow Cytometry]

To establish 10-color fluorescent antibody combination panels for the detection of minimal residual disease (MRD) of acute myeloid leukemia (AML) in our laboratory and discuss the value of clinical application.

According to the antigen expression characteristics of leukemia cells of incipient AML patients, MRD in bone marrow were detected by multiparameter flow cytometry, and the test results were compared with both bone marrow cell morphology and PCR results, then 10-color fluorescent antibody combination panels in our lab for MRD detection was determined.

The immunophenotypic characteristics of 392 incipient patients with AML in the First Affiliated Hospital of Zhengzhou University were analyzed, among them 357 (91.07%) cases showed abnormal immunophenotypes, which mainly included cross-lineage expression, cross-stage expression, deficiency of antigen expression or abnormal antigen intensity and other abnormal expression. The 10-color fluorescent antibody combination panels established according to abnormal immunophenotypic characteristics of leukemia cells were applied for detecting MRD in 156 patients with AML, the positive rate (43.6%) was higher than 26.8% of morphology, and the results were highly consistent with PCR detection results (96.49%), moreover, the recurrence rate of MRD positive patients (86.96%) was significantly higher than 5.75% of MRD negative patients. Therefore, this method could truly reflect the load of leukemia cells and prompt change of disease condition.

Multiparameter flow cytometry can detect various abnormal immunophenotypes of AML. The 10-color fluorescent antibody combination panels in our lab based on the characteristics of antigens expression in leukemia cells can well detect MRD of leukemia cells, so as to predict relapse and provide basis for clinical treatment.