Anti-tumor cytotoxicity of gammadelta T cells expanded from peripheral blood cells of patients with myeloma and lymphoma.

In order to establish an efficient gammadelta T cell-mediated immunotherapy for hematological malignancies, we attempted to evaluate cytotoxicity against tumor cells by gammadelta T cells, which were generated from blood cells of patients with myeloma and lymphoma by culturing with zoledronate and a low dose of IL-2. Although gammadelta T cells were expanded in patients with myeloma and lymphoma as well as normal persons, the amplification rates of gammadelta T cells before and after culturing varied from patient to patient in myeloma and lymphoma. gammadelta T cells generated in patients with myeloma and lymphoma showed a potent cytotoxic ability against myeloma/lymphoma cell lines as shown in gammadelta T cells generated in normal subjects. In addition, gammadelta T cells generated in a patient with myeloma showed a cytotoxic ability against self myeloma cells freshly prepared from bone marrow. However, the same gammadelta T cells were demonstrated to be non-cytotoxic to normal cells of the patient. These data demonstrated that gammadelta T cells, which could be expanded in vitro from blood cells of patients with myeloma and lymphoma by culturing with zoledronate and IL-2, possess a sufficient cytotoxic ability against tumor cells. These findings suggested that in vitro generated patients' gammadelta T cells could be applied to gammadelta T cell-mediated immunotherapy for hematological malignancies.