Tumor-ActivatedTCRγδ+T Cells from Gastric Cancer Patients Induce the Antitumor Immune Response ofTCRαβ+T Cells via Their Antigen-Presenting Cell-Like Effects

Abstract

HumanγδT cells display the principal characteristics of professional antigen-presenting cells (APCs), in addition to playing a vital role in immunity through cytokine secretion and their cytotoxic activity. However, it is not clear whetherγδT cells perform APC-like functions under pathological conditions. In this study, we showed that, in contrast to peripheral-derivedγδT cells directly isolated from PBMCs of gastric cancer patients, tumor-activatedγδT cells not only killed tumor cells efficiently but also strongly induced primary CD4+and CD8+  αβT cells proliferation and differentiation. More importantly, they abrogated the immunosuppression induced by CD4+CD25+Treg cells and induced the cytotoxic function of CD8+  αβT cells from patients with gastric cancer. In conclusion, tumor-activatedγδT cells can induce adaptive immune responses through their APC-like functions, and these cells may be a potentially useful tool in the development of tumor vaccines and immunotherapy.