Examples of CLL-1 expression on CD34⁺CD38⁻ cells in diagnosis and follow-up samples. Gating was performed based on CD45^dim/SSC characteristics and CD34⁺ expression. Afterwards, CD38 and CLL-1 expression were determined. Similar to Figure 1, percentages shown concern the CLL-1⁺ and CLL-1⁻ populations within the CD34⁺CD38⁻ compartment. (A,B) An example of a patient who remained in continuous remission. This patient showed high CLL-1 expression on CD34⁺CD38⁻ cells at diagnosis (A) but not after chemotherapy (B). Note the similarity with CLL-1 expression on normal bone marrow CD34⁺CD38⁻ cells in Figure 1H. (C,D) A diagnosis and MRD picture, as in panels A and B, but now for a patient with a large proportion of CD34⁺CD38⁻ cells being CLL-1⁺ in the MRD sample (D). CLL-1 expression on CD34⁺CD38⁻ cells of an AML patient diagnosed with t(8,21), at diagnosis (E) and after first course of chemotherapy (F). In the remission sample, the malignant character of the CD34⁺CD38⁻CLL-1⁺ population could be confirmed using FISH technique.