Abstract:

Objective To investigate the expressions of CD123 and CD66c in childhood B-cell acute lymphoblastic leukemia （B-ALL） and their roles in monitoring minimal residual disease （MRD）. Methods Multiparameter flow cytometry （MFC） was used to determine the expressions of CD123 and CD66c in bone marrow samples of 141 children with newly diagnosed B-ALL. A total of 25 children with acute myeloid leukemia （AML） with complete remission after chemotherapy were enrolled as control group,and their bone marrow samples had a proportion of normal B-progenitor cells. The antigens being different from those of control group were selected as MRD monitoring markers,and they were combined with CD10/CD34/CD19/CD45 antibodies for MRD monitoring. Results The expressions of CD123 and CD66c in normal B-progenitor cells and mature B-lymphocytes were negative. In the 141 cases of childhood B-ALL,there were 88 cases （62.41%） with the positive expression of CD123 and 70 cases （49.65%） with the positive expression of CD66c,respectively. The number of CD123 used for MRD monitoring was 45,and that of CD66c was 52. There were 35 cases with both CD123 and CD66c used for MRD monitoring,and there were 62 cases with CD123 or CD66c used for MRD monitoring,which the coverage rate was 43.97%. CD123 and CD66c showed good stabilities in MRD monitoring,with no decay or decline of antigen expression. Conclusions CD123 and CD66c can be used for MRD monitoring of childhood B-ALL,which should be combined with other markers so as to improve the coverage of MRD monitoring.

Key words: CD123, CD66c, B-cell acute lymphoblastic leukemia, Minimal residual disease