CD226 and acute myeloid leukemia: We selected thirteen AML samples with high DNAM-1 expression on leukemic cells (SFI ≥ 5, 10–90% positive cells, median positivity 70%) and incubated them on immobilized recombinant human DNAM-1 ligands (rhCD112-Fc or rhCD155-Fc) or isotype control (human IgG1) for 24 h.