ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: First, highly pure Vδ1 T cells isolated from healthy donors were tested for their cytotoxic function against BCR-ABL+ CML cell lines including K562 (blast crisis), LAMA-84 and KYO-1 shown in Fig. 6A. All of the tested γδ T lymphocytes isolated from five HD showed low reactivity to CML tumor cell lines at 5:1 and 10:1 E:T ratio.