OBJECTIVETo study the immunophenotype and its relationship with clinical characteristics in children with acute lymphoblastic leukemia (ALL).

METHODSBone marrow or blood samples (2-3 mL) with heparin anticoagulation from 139 children with ALL were obtained, and immunophenotypes were identified by flow cytometry.

RESULTSIn 139 ALL children, there were 103 cases (74.1%) of B-ALL, 24 cases (17.3%) of T-ALL, 12 cases of T/B biphenotypic (8.6% of T/BALL). In the 103 children with B-ALL, CD19 (90.3%), CD10 (83.5%) and CD20 (27.2%) were expressed as major antigens. In the 24 children with T-ALL, the major antigens were CD3 (79.2%), CD7 (66.7%) and CD5 (33.3%). In the 12 children with B/T-ALL, T-lymphoid antigens included CD7 (50.0%) and CD5 (41.7%), while the B-lymphoid antigens included CD19 (50.0%) and CD10 (33.3%). Of the 139 children with ALL, 32 cases (23.0%) showed myeloid antigen expression (My+ ALL) and the main expression antigens were CD13, CD33, CD14 and MPO. CD34 was expressed in 31 cases. CD34-positive expression (15.6%) in My+ ALL children was significantly lower than in My-ALL children (24.3%). HLA-DR was expressed in 82 of the 139 ALL children. The expression of CD10, CD34 and HLA-DR in the standard-risk, medium risk, high-risk ALL children was significantly different. There were significant differences in gender and incidence of bleeding between the My+ ALL and My-ALL groups (P<0.05).

CONCLUSIONSImmunetyping can differentiate the sources of leukemic cells. The expression of CD10, CD34 and HLA-DR antigen is related to the clinical classification of ALL.