IL-27 Induces CCL5 Production by T Lymphocytes, Which Contributes to Antitumor Activity.

Area of Science:

• Immunology
• Cytokine Signaling
• Cancer Biology

Background:

• Interleukin-27 (IL-27) is a pleiotropic cytokine with diverse immune regulatory functions.
• T lymphocytes play critical roles in immune responses, including anti-tumor immunity.

Purpose of the Study:

• To investigate the direct effects of IL-27 on T lymphocyte chemokine production.
• To elucidate the role of IL-27-induced CCL5 in anti-tumor immunity.

Main Methods:

• In vitro and in vivo studies using T lymphocytes (CD4+ and CD8+).
• Analysis of CCL5 production via IL-27 receptor (IL-27R) and STAT signaling pathways (STAT1, STAT3).
• Chromatin immunoprecipitation assays to assess transcription factor binding to the CCL5 promoter.
• Tumor-bearing mouse models treated with IL-27, anti-CCL5, or CCL5 mRNA delivered via lipid nanoparticles.

Main Results:

• IL-27 directly induces CCL5 production in T lymphocytes, particularly CD8+ T cells, in an IL-27R-dependent manner.
• CCL5 induction in CD4+ T cells relies on STAT1, while CD8+ T cells show STAT1-independent induction, with STAT3 binding to the CCL5 promoter.
• IL-27 administration in tumor-bearing mice significantly increased CCL5 production in tumor-infiltrating T cells.
• IL-27's anti-tumor effect was diminished by anti-CCL5 treatment, and direct CCL5 mRNA delivery inhibited tumor growth.

Conclusions:

• IL-27 robustly induces CCL5 production by T cells, contributing significantly to its anti-tumor activity.
• Targeting the IL-27-CCL5 axis in T cells represents a promising strategy for cancer immunotherapy.