Authors:
Natalia Martin-Orozco, Pawel Muranski, Yeonseok Chung, Xuexian O. Yang, Tomohide Yamazaki, Sijie Lu, Patrick Hwu, Nicholas P. Restifo, Willem W. Overwijk, and Chen Dong
Summary:
Although T helper 17 (Th17) cells have been found in tumor tissues, their function in cancer immunity is unclear. We found that interleukin-17A (IL-17A)-deficient mice were more susceptible to developing lung melanoma. Conversely, adoptive T cell therapy with tumor-specific Th17 cells prevented tumor development. Importantly, the Th17 cells retained their cytokine signature and exhibited stronger therapeutic efficacy than Th1 cells. Unexpectedly, therapy using Th17 cells elicited a remarkable activation of tumor-specific CD8+ T cells, which were necessary for the antitumor effect. Th17 cells promoted dendritic cell recruitment into the tumor tissues and in draining lymph nodes increased CD8α+ dendritic cells containing tumor material. Moreover, Th17 cells promoted CCL20 chemokine production by tumor tissues, and tumor-bearing CCR6-deficient mice did not respond to Th17 cell therapy. Thus, Th17 cells elicited a protective inflammation that promotes the activation of tumor-specific CD8+ T cells. These findings have important implications in antitumor immunotherapies.
Source:
Immunity; Vol. 31, Issue 5, 787-798 (10/29/09)