bims-imseme Biomed News
on Immunosenescence and T cell metabolism
Issue of 2025–04–27
fourteen papers selected by
Pierpaolo Ginefra, Ludwig Institute for Cancer Research



  1. Trends Cancer. 2025 Apr 22. pii: S2405-8033(25)00094-9. [Epub ahead of print]
      Tumors subvert T cell metabolism through diverse mechanisms. Ikeda et al. reveal mitochondrial transfer as a tumor-driven immune evasion strategy, where cancer cells deliver dysfunctional mitochondria to T cells, impairing metabolism and inducing exhaustion. These findings highlight mitochondrial dynamics as a promising therapeutic target to improve immunotherapy outcomes.
    Keywords:  T cell exhaustion; cancer immunotherapy; mitochondrial transfer; tumor microenvironment
    DOI:  https://doi.org/10.1016/j.trecan.2025.04.002
  2. Nat Cell Biol. 2025 Apr 21.
      Nutrient stress represents an important barrier for anti-tumour immunity, and tumour interstitial fluid often contains metabolites that hinder immune function. However, it is difficult to isolate the effects of tumour nutrient stress from other suppressive factors. Thus, we used a chemically defined cell culture medium based on the metabolomic profile of tumour interstitial fluid: tumour interstitial fluid medium (TIFM). Culture of CD8+ T cells in TIFM limited cell expansion and impaired CD8+ T cell effector functions upon restimulation, suggesting that tumour nutrient stress alone is sufficient to drive T cell dysfunction. We identified phosphoethanolamine (pEtn), a phospholipid intermediate, as a driver of T cell dysfunction. pEtn dampened T cell receptor signalling by depleting T cells of diacylglycerol required for T cell receptor signal transduction. The reduction of pEtn accumulation in tumours improved intratumoural T cell function and tumour control, suggesting that pEtn accumulation plays a dominant role in immunosuppression in the tumour microenvironment.
    DOI:  https://doi.org/10.1038/s41556-025-01650-9
  3. Mol Immunol. 2025 Apr 22. pii: S0161-5890(25)00104-X. [Epub ahead of print]182 139-149
      Adoptive transfer of TCR-specific CD8+ T cells represents a powerful experimental platform for investigating tumor-specific CD8+ T cell responses within the framework of anti-tumor immunity. Genetic modulation of these transferred cells provides a robust strategy to elucidate the intrinsic molecular mechanisms underlying T cell differentiation and functionality, thereby offering critical insights to optimize tumor-specific CD8+ T cell antitumor immunity in cancer immunotherapy. A key aspect of this approach is the ex vivo activation of primary T cells, which raises important questions regarding the impact of pre-activation on subsequent T cell differentiation. In this study, we explored the differentiation trajectories of pre-activated CD8+ T cells and performed a comprehensive characterization of their epigenetic and transcriptional profiles using a murine melanoma model. Our findings revealed that ex vivo pre-activation not only attenuates progression towards terminal exhaustion in the tumor-draining lymph nodes (TdLNs) but also enhances the stem-like characteristics of CD8+ T cells within the tumor microenvironment (TME). Leveraging comprehensive ATAC-seq and RNA-seq analyses, we demonstrated that pre-activation modulates the epigenetic landscape and transcriptional profile of CD8+ T cells, fostering effector-related differentiation in the TdLNs while promoting stemness-associated programming in the TME. These findings highlight the profound influence of ex vivo pre-activation on the differentiation pathways of tumor-specific CD8+ T cells, underscoring the necessity of taking these experimental framework-induced discrepancies into consideration for more accurate data interpretation in relevant researches.
    Keywords:  Epigenetic and transcriptional profiling; Exhausted T cell; Stem-like exhausted T cell; T cell pre-activation; Tumor-specific CD8(+) T cell
    DOI:  https://doi.org/10.1016/j.molimm.2025.04.007
  4. Annu Rev Immunol. 2025 Apr;43(1): 515-543
      CD8 T cells play a critical role in antitumor immunity. However, over time, they often become dysfunctional or exhausted and ultimately fail to control tumor growth. To effectively harness CD8 T cells for cancer immunotherapy, a detailed understanding of the mechanisms that govern their differentiation and function is crucial. This review summarizes our current knowledge of the molecular pathways that regulate CD8 T cell heterogeneity and function in chronic infection and cancer and outlines how T cells respond to therapeutic checkpoint blockade. We explore how T cell-intrinsic and -extrinsic factors influence CD8 T cell differentiation, fate choices, and functional states and ultimately dictate their response to therapy. Identifying cells that orchestrate long-term antitumor immunity and understanding the mechanisms that govern their development and persistence are critical steps toward improving cancer immunotherapy.
    Keywords:  PD-1; chronic infection; epigenetic regulators; exhausted CD8 T cells; tissue-resident memory T cells; transcription factors
    DOI:  https://doi.org/10.1146/annurev-immunol-082223-044122
  5. Cancer Lett. 2025 Apr 17. pii: S0304-3835(25)00294-0. [Epub ahead of print] 217728
      Tumor-associated macrophages (TAMs) play a multifaceted role in the tumor microenvironment, notably by suppressing antitumor immune responses through immunosuppressive mechanisms. TAMs secrete a range of cytokines that simultaneously inhibit T cell function and foster a microenvironment that supports tumor progression and dissemination. Our study has delved into the intricate relationship between the metabolic reprogramming of TAMs and their impact on tumor progression. Mitochondrial metabolic reprogramming mediated by the SENP1-Sirt3 axis altered the dynamics and activity of tumor-infiltrating immune cells, including macrophages and CD8+ T lymphocytes. SENP1-Sirt3 axis increases the level of acetyl-CoA in macrophage mitochondria, which in turn promotes cholesterol biosynthesis in macrophages. The upregulation of cholesterol synthesis is a key factor in driving macrophage polarization towards the immunosuppressive M2 phenotype, which in turn supports tumor development. Notably, increased cholesterol levels contributed to a reduction in the number and activity of CD8+ T cells, which are essential for mounting an effective immune response against cancer cells. These findings suggest that targeting cholesterol biosynthesis in TAMs may be a promising strategy for cancer immunotherapy. SIGNIFICANCE: Activation of the SENP1-Sirt3 axis initiates mitochondrial metabolic reprogramming in tumor-associated macrophages (TAMs), leading to enhanced cholesterol and acetyl-CoA production, M2 macrophage polarization, and impaired CD8+ T cell anti-tumor responses.
    Keywords:  SENP1-Sirt3 axis; acetyl-CoA; cholesterol biosynthesis; tumor-associated macrophages
    DOI:  https://doi.org/10.1016/j.canlet.2025.217728
  6. Cell Death Discov. 2025 Apr 19. 11(1): 186
      Renal cell carcinoma (RCC), a therapeutically recalcitrant genitourinary malignancy, exemplifies the profound interplay between oncogenic signaling and metabolic adaptation. Emerging evidence positions metabolic reprogramming as a central axis of RCC pathogenesis, characterized by dynamic shifts in nutrient utilization that transcend canonical Warburg physiology to encompass lipid anabolism, glutamine auxotrophy, and microenvironment-driven metabolic plasticity. This orchestrated rewiring of cellular energetics sustains tumor proliferation under hypoxia while fostering immunosuppression through metabolite-mediated T cell exhaustion and myeloid-derived suppressor cell activation. Crucially, RCC exhibits metabolic heterogeneity across histological subtypes and intratumoral regions-a feature increasingly recognized as a determinant of therapeutic resistance. Our review systematically deciphers the molecular architecture of RCC metabolism, elucidating how VHL/HIF axis mutations, mTOR pathway dysregulation, and epigenetic modifiers converge to reshape glucose flux, lipid droplet biogenesis, and amino acid catabolism. We present novel insights into spatial metabolic zonation within RCC tumors, where pseudohypoxic niches engage in lactate shuttling and cholesterol efflux to adjacent vasculature, creating pro-angiogenic and immunosuppressive microdomains. Therapeutically, we evaluate first-in-class inhibitors targeting rate-limiting enzymes in de novo lipogenesis and glutamine metabolism, while proposing biomarker-driven strategies to overcome compensatory pathway activation. We highlight the synergy between glutaminase inhibitors and PD-1 blockade in reinvigorating CD8+ T cell function, and the role of lipid-loaded cancer-associated fibroblasts in shielding tumors from ferroptosis. Finally, we outline a translational roadmap integrating multi-omics profiling, functional metabolomics, and spatial biology to match metabolic vulnerabilities with precision therapies.
    DOI:  https://doi.org/10.1038/s41420-025-02479-9
  7. Cell Rep. 2025 Apr 21. pii: S2211-1247(25)00381-X. [Epub ahead of print]44(5): 115610
      Short-lived effector cells are characterized metabolically by a highly glycolytic state, driving energy and biomass acquisition, whereas memory-fated T cells have historically been described as meeting these requirements through mitochondrial metabolism. Here, we show that the mitochondrial protein optic atrophy 1 (OPA1) is critical for rapidly dividing CD8 T cells in vivo, the requirement for which is most pronounced in effector CD8 T cells. More specifically, OPA1 supports proper cell cycle initiation and progression and the viability and survival of CD8 T cells during clonal expansion. Use of mice deficient in the mitochondrial membrane fusion proteins Mitofusin 1 and 2 (MFN1/2) in both in vivo proliferation/differentiation assays and ex vivo metabolic analysis indicates that the requirement for OPA1 during cell division supersedes its role in mitochondrial fusion. We conclude that OPA1 is critical for the generation and accumulation of short-lived effector cells that arise during the response to infection.
    Keywords:  CD8; CP: Immunology; Mitofusins; Opa1; T cell; metabolism
    DOI:  https://doi.org/10.1016/j.celrep.2025.115610
  8. Cancer Immunol Res. 2025 Apr 22.
      NEDDylation is a post-translational modification whereby the ubiquitin-like molecule NEDD8 is attached to protein substrates in a process dependent on NEDD8 activating enzyme regulatory subunit (NAE1). NEDDylation is emerging as a regulator of cancer biology, but its precise role in antitumor immunity has not been thoroughly characterized. Here, we study the impact of NEDDylation in CD8+ T cell-mediated antitumor responses. Analysis of publicly available single-cell RNA sequencing databases revealed that CD8+ tumor-infiltrating lymphocytes (TILs) showed increased expression of NEDD8 during their differentiation into effector memory cells. In vitro activation of mouse and human CD8+ T cells drove the upregulation of the NEDDylation enzymatic pathway, resulting in an enrichment of NEDDylated proteins. In vivo tumor challenge assays demonstrated that CD8+ T cells lacking NAE1 (NAE1-KO) exhibited reduced antitumor capability and a less activated phenotype with compromised differentiation into effector cells. Upregulating NEDDylation by knocking out deNEDDylase sentrin-specific protease 8 (SENP8) increased the in vitro cytotoxic capability of CD8+ CAR T cells. In addition, LC MS/MS proteomic analyses of NAE1-KO CD8+ T cells and CD8+ T cells treated with the NEDDylation inhibitor MLN4924, showed a pronounced impairment in metabolic pathways, including glycolysis and oxidative phosphorylation. In this context, we validated lactate dehydrogenase A, α-enolase and hexokinase 1, which are relevant glycolytic enzymes, as NEDD8 targets. In line with this, NEDDylation-deficient CD8+ T cells demonstrated reduced transcription, protein expression and enzymatic activity of lactate dehydrogenase. In summary, we uncover NEDDylation as a critical regulator of CD8+ T cell-mediated antitumor immunity.
    DOI:  https://doi.org/10.1158/2326-6066.CIR-24-0127
  9. Front Immunol. 2025 ;16 1548509
       Background: The ability of immune cells to rapidly respond to pathogens or malignant cells is tightly linked to metabolic pathways. In cancer, the tumor microenvironment (TME) represents a complex system with a strong metabolism stress, in part due to glucose shortage, which limits proper T cell activation, differentiation and functions preventing anti-tumor immunity.
    Methods: In this study, we evaluated T cell immune reactivity in glucose-restricted mixed lymphocyte reaction (MLR), using a comprehensive profiling of soluble factors, multiparametric flow cytometry and single cell RNA sequencing (scRNA-seq).
    Results: We determined that glucose restriction potentiates anti-PD-1 immune responses and identified thioredoxin-interacting protein (TXNIP), a negative regulator of glucose uptake, as a potential immunometabolic modulator of T cell activation. We confirmed TXNIP downregulation in tumor infiltrating T cells in cancer patients. We next investigated the implication of TXNIP in modulating immune effector functions in primary human T cells and showed that TXNIP depletion increased IFN-γ secretion and tumor cell killing.
    Conclusions: TXNIP is at the interface between immunometabolism and T cell activation and could represent a potential target for immuno-oncology treatments.
    Keywords:  T cells activation; TXNIP; cancer immunotherapy; glucose deprivation; mixed lymphocyte reaction; single-cell RNA-sequencing; tumor microenvironment
    DOI:  https://doi.org/10.3389/fimmu.2025.1548509
  10. Nat Cell Biol. 2025 Apr 21.
      Nicotinamide adenine dinucleotide phosphate (NADPH) is a vital electron donor essential for macromolecular biosynthesis and protection against oxidative stress. Although NADPH is compartmentalized within the cytosol and mitochondria, the specific functions of mitochondrial NADPH remain largely unexplored. Here we demonstrate that NAD+ kinase 2 (NADK2), the principal enzyme responsible for mitochondrial NADPH production, is critical for maintaining protein lipoylation, a conserved lipid modification necessary for the optimal activity of multiple mitochondrial enzyme complexes, including the pyruvate dehydrogenase complex. The mitochondrial fatty acid synthesis (mtFAS) pathway utilizes NADPH for generating protein-bound acyl groups, including lipoic acid. By developing a mass-spectrometry-based method to assess mammalian mtFAS, we reveal that NADK2 is crucial for mtFAS activity. NADK2 deficiency impairs mtFAS-associated processes, leading to reduced cellular respiration and mitochondrial translation. Our findings support a model in which mitochondrial NADPH fuels the mtFAS pathway, thereby sustaining protein lipoylation and mitochondrial oxidative metabolism.
    DOI:  https://doi.org/10.1038/s41556-025-01655-4
  11. Annu Rev Immunol. 2025 Apr;43(1): 343-366
      T lymphocytes are essential for immune responses to pathogens and tumors. Their ability to rapidly clonally expand and differentiate to effector cells following infection, and then to curb effector function following infection clearance, is fundamental for adaptive immunity. Proteome remodeling in response to immune activation is a fundamental mechanism that allows T cells to swiftly reprogram for acquisition of effector function and is possible only because antigen receptor- and cytokine-driven signal transduction pathways can trigger massive increases in protein synthesis. Equally, the ability to repress protein synthesis supports a return to quiescence once pathogens are cleared to avoid autoimmunity and to generate memory T cell populations. This review discusses what is known about T cell proteomes and the regulatory mechanisms that control protein synthesis in T cells. The focus is on how this fundamental process is dynamically controlled to ensure immune homeostasis.
    Keywords:  Myc; T cells; amino acid transporters; mammalian target of rapamycin complex 1; protein synthesis; translation
    DOI:  https://doi.org/10.1146/annurev-immunol-082323-035253
  12. Nat Commun. 2025 Apr 24. 16(1): 3860
      Conventional CD4 T cells represent a major source of inflammatory mediators that drive progression of chronic liver disease to fibrosis and to end-stage cirrhosis. Identification of T cell pathways that limits the inflammatory response could thus have therapeutic relevance. Here we show, using both human samples and mouse models, that autophagy is deficient in CD4 T cells from patients with advanced fibrosis, and that loss of autophagy following genomic deletion of ATG5 in T cells is associated with the emergence of pathogenic IL-17A + IFN-γ + Th17 T cells that drive liver fibrosis in mice. Mechanistically, liver CD4 T cells lacking autophagy display a Th17 glycolytic phenotype associated with enhanced type 3 cytokine (i.e., IL-17A and GM-CSF) release, shifting hepatic myofibroblasts, hepatocytes and macrophages toward a proinflammatory phenotype. We also show that autophagy can be rescued in CD4 T cells from patients with extensive liver fibrosis, leading to decreased frequency of pathogenic Th17 cells and reduced GM-CSF levels; in addition, limited fibrosis is observed in mice in which Rubicon, a negative regulator of autophagy, is deleted specifically in their T cells. Our findings thus implicate autophagy in CD4 T cells as a key therapeutic target to control inflammation-driven fibrosis during chronic liver injury.
    DOI:  https://doi.org/10.1038/s41467-025-59218-y