NK cells possess a native ability to kill tumors and virally infected cells without prior antigen priming. Furthermore, NK cells can be administered to patients across HLA allotypes, unlike T cells which require HLA matching to avoid graft-versus-host disease. Many trials utilizing adoptive transfer of allogeneic NK cells demonstrated complete remissions in patients with acute myelogenous leukemia (AML) who are refractory to standard chemotherapy. Another recent clinical study demonstrated effective treatment of lymphoid malignancies using allogeneic CAR-expressing NK cells, with minimal side effects. Thus, NK cells possess a number of advantages over T cells that enables them to be used as safe, effective, “off-the-shelf” adoptive cell therapy product to treat diverse malignancies. Antibody-dependent cellular cytotoxicity (ADCC) is a key pathway that mediates natural killer (NK) cell cytotoxicity against antibody-opsonized target cells. This process helps mediate the therapeutic efficacy of anti-tumor antibodies. On NK cells, ADCC occurs via engagement of antibody-coated target cells with activating receptor leading to proinflammatory cytokine upregulation, degranulation, and target cell death. Upon cellular activation, the is cleaved from the NK cell surface. Cleavage of the ectodomain prevents further antibody binding and signaling, which dampens NK cell activity. Blocking activation-induced cleavage has been previously demonstrated to augment ADCC activity and provides a novel strategy to improve efficacy of therapeutic antibodies in combination with adoptive transfer of engineered NK cells.