Expression of NKG2D ligands MICA/B on CD34 CML cells. From left to right: patients 5, 6, 8, and 14. Top panel: CD34⁺ CML cells and normal CD34⁺ cells were stained with polyclonal anti-MICA/B (solid line) or isotype antibodies (dashed line). Middle panel: direct binding of an NKG2D/Fc chimeric molecule to the CD34 CML cells from the indicated patients (solid lines). The bound NKG2D/Fc was detected by a PE-conjugated anti-NKG2D that was also used as a negative control (dashed lines). Lower panel: direct binding of NKG2D/Fc (solid line) to MICA⁺ HeLa cells or PE-conjugated anti-NKG2D used as negative control (dashed lines). HeLa cells were used as an internal positive control for each patient indicated in the middle panel (variability of HeLa staining may reflect batch or dose variation in NKG2D/Fc antibody).