Adenosine mediates functional and metabolic suppression of peripheral and tumor-infiltrating CD8+ T cells
Creators
- Mastelic-Gavillet, Beatris1
- Navarro Rodrigo, Blanca1
- Décombaz, Laure2
- Wang, Haiping1
- Ercolano, Giuseppe3
- Ahmed, Rita1
- Lozano, Leyder Elena2
- Ianaro, Angela3
- Derré, Laurent4
- Valerio, Massimo4
- Tawadros, Thomas4
- Jichlinski, Patrice4
- Nguyen-Ngoc, Tu1
- Speiser, Daniel E.2
- Verdeil, Grégory2
- Gestermann, Nicolas2
- Dormond, Olivier5
- Kandalaft, Lana1
- Coukos, George1
- Jandus, Camilla1
- Ménétrier-Caux, Christine6
- Caux, Christophe6
- Ho, Ping-Chih1
- Romero, Pedro2
- Harari, Alexandre1
- Vigano, Selena1
- 1. Department of Oncology, Ludwig Institute for Cancer Research Lausanne, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
- 2. Department of Oncology, University of Lausanne, Lausanne, Switzerland
- 3. Department of Pharmacy, University of Naples Federico II, Naples, Italy
- 4. Department of Urology, Urology Research Unit, CHUV, Lausanne, Switzerland
- 5. Department of Visceral Surgery, CHUV, Lausanne, Switzerland
- 6. Department of Immunology Virology and Inflammation, Univ Lyon, Université Claude Bernard Lyon 1, 69008, Lyon, France
Description
Background: Several mechanisms are present in the tumor microenvironment (TME) to impair cytotoxic T cell responses potentially able to control tumor growth. Among these, the accumulation of adenosine (Ado) contributes to tumor progression and represents a promising immunotherapeutic target. Ado has been shown to impair T cell effector function, but the role and mechanisms employed by Ado/Ado receptors (AdoRs) in modulating human peripheral and tumor-infiltrating lymphocyte (TIL) function are still puzzling.
Methods: CD8+ T cell cytokine production following stimulation was quantified by intracellular staining and flow cytometry. The cytotoxic capacity of tumor infiltrating lymphocytes (TILs) was quantified by the chromium release assay following co-culture with autologous or anti-CD3-loaded tumor cell lines. The CD8+ T cell metabolic fitness was evaluated by the seahorse assay and by the quantification of 2-NBDG uptake and CD71/CD98 upregulation upon stimulation. The expression of AdoRs was assessed by RNA flow cytometry, a recently developed technology that we validated by semiquantitative RT-PCR (qRT-PCR), while the impact on T cell function was evaluated by the use of selective antagonists and agonists. The influence of Ado/AdoR on the PKA and mTOR pathways was evaluated by phosphoflow staining of p-CREB and p-S6, respectively, and validated by western blot.
Results: Here, we demonstrate that Ado signaling through the A2A receptor (A2AR) in human peripheral CD8+ T cells and TILs is responsible for the higher sensitivity to Ado-mediated suppression of T central memory cells. We confirmed that Ado is able to impair peripheral and tumor-expanded T cell effector functions, and we show for the first time its impact on metabolic fitness. The Ado-mediated immunosuppressive effects are mediated by increased PKA activation that results in impairment of the mTORC1 pathway.
Conclusions: Our findings unveil A2AR/PKA/mTORC1 as the main Ado signaling pathway impairing the immune competence of peripheral T cells and TILs. Thus, p-CREB and p-S6 may represent useful pharmacodynamic and efficacy biomarkers of immunotherapies targeting Ado. The effect of Ado on T cell metabolic fitness reinforces the importance of the adenosinergic pathway as a target for next-generation immunotherapy.