CD33 and myelodysplastic syndrome: The cytotoxicity of the calichemicin-conjugated ADC gemtuzumab and the PBD-conjugated anti-CD33, -CD123, -CCRL2 ADCs were assessed in AML cell lines derived from patients with de novo/TP53-wild type AML (MOLM13, OCI-AML3 and MV4–11) (Fig. 2A–C) and MDS/AML cell lines (TF-1 - erythroleukemia, F36P – MDS-related erythroleukemia, and SKM1 – TP53-mutated MDS/AML) (Fig. 2D–F).