| First Author | Martí i Líndez AA | Year | 2019 |
| Journal | JCI Insight | Volume | 4 |
| Issue | 24 | PubMed ID | 31751318 |
| Mgi Jnum | J:285235 | Mgi Id | MGI:6393394 |
| Doi | 10.1172/jci.insight.132975 | Citation | Marti i Lindez AA, et al. (2019) Mitochondrial arginase-2 is a cellautonomous regulator of CD8+ T cell function and antitumor efficacy. JCI Insight 4(24) |
| abstractText | As sufficient extracellular arginine is crucial for T cell function, depletion of extracellular arginine by elevated arginase 1 (Arg1) activity has emerged as a hallmark immunosuppressive mechanism. However, the potential cell-autonomous roles of arginases in T cells have remained unexplored. Here, we show that the arginase isoform expressed by T cells, the mitochondrial Arg2, is a cell-intrinsic regulator of CD8+ T cell activity. Both germline Arg2 deletion and adoptive transfer of Arg2-/- CD8+ T cells significantly reduced tumor growth in preclinical cancer models by enhancing CD8+ T cell activation, effector function, and persistence. Transcriptomic, proteomic, and high-dimensional flow cytometry characterization revealed a CD8+ T cell-intrinsic role of Arg2 in modulating T cell activation, antitumor cytoxicity, and memory formation, independently of extracellular arginine availability. Furthermore, specific deletion of Arg2 in CD8+ T cells strongly synergized with PD-1 blockade for the control of tumor growth and animal survival. These observations, coupled with the finding that pharmacologic arginase inhibition accelerates activation of ex vivo human T cells, unveil Arg2 as a potentially new therapeutic target for T cell-based cancer immunotherapies. |
