Ncam1 is highly expressed in murine leukemic Mll-Af9 stem cells. (A) Expression of Ncam1 was compared between normal hematopoietic and different leukemic progenitor populations in the indicated gene expression data sets. (B) Ncam1 cell surface expression in different normal and leukemic progenitor populations was analyzed by flow cytometry. Shown are scatter plots of representative samples (left) depicting the gating strategy to compare Ncam1 expression in GMP vs L-GMP. Right, Bar graphs showing the percentage of Ncam1 expression in indicated hematopoietic populations. Error bars represent mean of 3 biological replicates ± SD of mean. (C) Kaplan-Meier survival curves of recipient animals transplanted with equal amounts of B6-M/A9 or N^−/−-M/A9 whole BM cells. Differences were compared by the log-rank test. (D) Representative scatter plots showing expression of GFP, c-Kit, Gr1, B220, and Mac1 in normal murine BM (B6_BM) and spleen (B6_Spleen) cells and B6-M/A9 and N^−/−-M/A9 spleen cells (left). The percentage of positive labeled cells of B6-M/A9 and N^−/−-M/A9 samples was compared by 2-tailed Student t test (right). Error bars represent mean of 8 biological replicates ± SD of mean.