Possible Application of Ascites-infiltrating Gamma-delta T Cells for Adoptive Immunotherapy

Malignant ascites contain many tumour-infiltrating lymphocytes. γδ T cells with antitumour activity have attracted attention as effector cells in cancer immunotherapy. Vδ2+ T cells were cultured from peripheral blood mononuclear cells (PBMCs) and ascites-infiltrating lymphocytes (AILs) to compare the differences in response to 2-methyl-3-butenyl-1-pyrophosphate (2M3B1-PP) and zoledronate (Zol) as antigens in vitro.To expand Vδ2+ T cells from PBMCs and AILs from 29 patients with cancer, these cells were cultured and subjected to analysis.The proliferation rate of Vδ2+ T cells was higher in both PBMCs and AILs when cultured with Zol than with 2M3B1-PP. Although Vδ2+ T cells show a higher rate of expansion in AILs compared to PBMCs, the number of mixed tumour cells in ascites was decreased when cultured with Zol.Vδ2+ T cells in AILs are cytotoxic to tumour cells in ascites and may be considered in adoptive immunotherapy.