CD33 and acute myeloid leukemia: Namely, the percentages of cells positive for a given marker in the AML versus (vs.)HC samples were as follows: (mean of the 14 cases): CD33 (73.2 vs. 8.5%), CD34 (37.4 vs. 0.2%), CD38 (68.5 vs. 20.9%), CD117 (53.7 vs. 4.6%), CD135 (45.3 vs. 6.8%) (Figure 1A).