AC133 expression on acute myeloid leukemia blasts: correlation to FAB and to CD34 expression and possible implications for peripheral blood progenitor cell purging in AML

AC133 is an antigen expressed on CD34 + hematopoietic progenitor cells. In acute myeloid leukemia (AML) it is expressed on leukemic blasts of most FAB subtypes. However, few data are available regarding coexpression of other surface antigens. We measured AC133 expression on AML blasts from 28 consec utive patients at initial diagnosis (n = 26) or at diagnosis of first relap se (n = 2) and on 26 leukapheresis products from 14 patients. In AML AC133 correlated with CD34 expression (Spearman r = 0.4711, P = 0.0114) and even stronger with combined CD34/CD33 expression (Spearman r = 0.5083, P = 0.006 8). In leukapheresis products AC133 expression correlated with CD34 express ion (Spearman r = 0.7495, P = 0.002) and the yield of the obtained amount o f CD34 + cells (Spearman r = 0.6484, P = 0.0121). In conclusion AC133 expre ssion is closely related to CD34 expression in AML. In leukapheresis produc ts AC133 provides an additional marker for selection of PBPC autografts in AC133-AML. (C) 2001 Elsevier Science Ltd. All rights reserved.