| Autor: |
Satomi Ando, Charles M. Perkins, Yamato Sajiki, Chase Chastain, Rajesh M. Valanparambil, Andreas Wieland, William H. Hudson, Masao Hashimoto, Suresh S. Ramalingam, Gordon J. Freeman, Rafi Ahmed, Koichi Araki |
| Rok vydání: |
2022 |
| Předmět: |
|
| Zdroj: |
The Journal of clinical investigation. |
| ISSN: |
1558-8238 |
| Popis: |
T cell exhaustion is a state of T cell dysfunction associated with expression of programmed death 1 (PD-1). Exhausted CD8 T cells are maintained by self-renewing stem-like T (TSL) cells that provide differentiated TIM3+ cells, a part of which possesses effector-like properties. PD-1-targeted therapies enhance T cell response by promoting differentiation of TSL cells toward TIM3+ cells, but the role of mTOR during T cell exhaustion remains elusive. Here, we show that mTOR inhibition has distinct outcomes during the beginning of and after the establishment of chronic viral infection. Blocking mTOR during the T cell expansion phase enhanced the T cell response by accumulating TSL cells, leading to improved efficacy of PD-1 immunotherapy. Whereas, after exhaustion progressed, mTOR inhibition caused immunosuppression characterized by decreased TIM3+ cells and increased viral load with minimal changes in TSL cells. Mechanistically, a cell-intrinsic mTOR signal was vital for differentiation of TSL cells into the TIM3+ state in the early and late phases of chronic infection as well as during PD-1 immunotherapy. Thus, PD-1 blockade worked after cessation of mTOR inhibition but simultaneous treatment failed to induce functional TIM3+ cells, reducing efficacy of PD-1 immunotherapy. Our data demonstrate that mTOR regulates T cell exhaustion and have important implications for combination cancer therapies with PD-1 blockade. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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