부산대학교 도서관

While a high frequency of Th1 cells in tumors is associated with improved cancer prognosis, this benefit has been attributed mainly to support of cytotoxic activity of [CD8.sup.+] T cells. By attempting to potentiate antibody-driven immunity, we found a remarkable synergy between [CD4.sup.+] T cells and tumor- binding antibodies. This surprising synergy was mediated by a small subset of tumor-infiltrating [CD4.sup.+] T cells that express the high-affinity Fc[gamma] receptor for IgG (Fc[gamma]RI) in both mouse and human patients. These cells efficiently lyse tumor cells coated with antibodies through concomitant crosslinking of their T cell receptor (TCR) and Fc[gamma]RI. By expressing Fc[gamma]RI and its signaling chain in conventional [CD4.sup.+] T cells, we successfully employed this mechanism to treat established solid cancers. Overall, this discovery sheds new light on the biology of this T cell subset, their function during tumor immunity, and the means to utilize their unique killing signals in immunotherapy.
Introduction Over recent decades, researchers exerted tremendous efforts to dissect the biological and clinical roles of immune-cell populations that infiltrate tumors (1-3). While it is widely accepted that increased prevalence [...]