Elimination of tumor-infiltrating regulatory T cells for enhancing anti-tumor immunity

 

Naganari Ohkura

Experimental Immunology, IFReC, Osaka University

 

 

Regulatory T (Treg) cells are a subgroup of CD4⁺ T cells essential for maintaining immune homeostasis, and repress aberrant and excessive immune responses. Based on these characteristics, Treg-control is considered to be effective in suppressing autoimmune diseases, and conversely, enhancing cancer immunity. Previous studies have shown that anti-tumor immune activity can be enhanced by removing Treg cells; however, systemic Treg elimination causes serious autoimmune diseases. We therefore analyzed the diversity of Treg cells using single-cell analysis platforms, and tried to identify a specific molecule of tumor-infiltrating Treg cells for enhancing anti-tumor immunity. By screening the molecule from tumors, we found that CCR8 was highly expressed in tumor-infiltrating Treg cells, but not in normal Treg and conventional T cells. As expected, anti-CCR8 antibody enhanced anti-tumor activity without any symptoms of autoimmune diseases in tumor-bearing mouse models. We hope that this molecule will become a promising target for cancer immunotherapy.

 

 References

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