T Helper 17 T Cells Do Good for Cancer Immunotherapy

Abstract

Evaluation of: Martin-Orozco N, Muranski P, Chung Y et al.: T helper 17 cells promote cytotoxic T cell activation in tumor immunity. Immunity 31(5), 787–798 (2009). The immune system plays an important role in tumor control. Tumor antigen-specific CD4⁺ and CD8⁺ T cells are being actively exploited in cancer immunotherapy protocols that often attain clinical responses. The T helper (Th)1 effector cytokine profile, epitomized by the production of IFN-γ, is considered the optimal pathway in controlling tumor growth. In this study, Martin-Orozco challenges this notion by demonstrating that newly defined Th17 effector T cells display a stronger anti-tumor effect vis a vis with Th1 cells. Th17 cells produce the strongly inflammatory cytokines IL-17A and IL-17F, and so far have been implicated in the response to infectious pathogens and in autoimmunity. This study reveals that Th17 cells protect against cancer, not only by triggering a potent nonantigen-specific intratumor inflammatory infiltrate, but also, and remarkably, by providing a more significant help than Th1 cells for the efficient induction, expansion, differentiation and tumor homing of tumor-specific CD8⁺ T cells. This study, therefore, sheds new light on the effector functions of Th17 cells and has strong implications for their translation into clinical applications for cancer immunotherapy.

KEYWORDS::

• adoptive immunotherapy
• Th17 cells
• tumor immunology
• vaccines

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.