CD33 and acute myeloid leukemia: Further studies showed that disrupting the natural killer group 2 member a (NKG2A) gene, killer cell lectin like receptor C1 (KLRC1), which encodes an inhibitory receptor on NK cells that often limits their tumour-killing ability through interaction with HLA-E on acute myeloid leukaemia (AML) cells, on CD33-specific CAR-NK cells demonstrated enhanced resistance to immune suppression.