Characteristics and monitoring of minimal residual disease in patients with T acute lymphoid leukemia by flow cytometry with two 4-color combinations of fluorescent antibodies / 中国实验血液学杂志

ABSTRACT

The purpose of this study was to establish a method for the monitoring of minimal residual disease (MRD) in bone marrow samples of the children with T acute lymphoid leukemia (T-ALL), and to evaluate its value in clinical application. The immuno-phenotype of the leukemic cells were detected by flow cytometry with two sets of 4-color combinations of antibodies against TdT/CD5/cCD3/HLA-DR(+)CD19(+)CD33 and CD34/CD5/cCD3/HLA-DR(+)CD19(+)CD33 in 32 cases of de novo T-ALL and were compared with the results in 10 normal controls. The antibody combination in regions of the two-parameter plots where the leukemic cells appeared were different from the normal cells was screened as the effective combination which was used to monitor MRD in the bone marrows of the T-ALL children after the inductive treatment. The results indicated that the respective effective frequencies of antibodies against TdT/CD5/cCD3/HLA-DR(+)CD19(+)CD33 and CD34/CD5/cCD3/HLA-DR(+)CD19(+)CD33 were 90.6% and 62.5%. 32 cases of childhood T-ALL were successively screened for antibodies combinations of interest and were identified in 100% (32/32) of these cases. After inductive treatment, the positive rate in 129 times of MRD monitoring was 19.4% (25/129) by flow cytometry and 5.43% (7/129) by FAB morphology. It is concluded that monitoring MRD in patients with T-ALL by flow cytometry with two 4 color combinations of fluorescent antibodies is an quick and effective method. The sensitivity of this method is high and it may be of important significance for the treatment and prognostic evaluation in childhood T-ALL.