Both CAR NK cells showed potent and specific antitumor activity on CD19-positive patient-derived primary tumor cell lines of various origin, including peripheral blood– or bone marrow–derived B-cell precursor leukemia cells from ALL or chronic myeloid leukemia patients and peripheral blood–derived B-cell lymphoma cells from a patient with non-Hodgkins lymphoma. Here, CD19 is linked to acute lymphoblastic leukemia.