bims-imseme 2025-11-30 papers

bims-imseme

Biomed News

on Immunosenescence and T cell metabolism

Issue of 2025–11–30
25 papers selected by
Pierpaolo Ginefra, Ludwig Institute for Cancer Research

Vitamin B6 preserves the stemness-like phenotypes and antitumor ability of CD8+ T cells.
Bhlhe40 Coordinates T Cell Programs with Distinct CD4 and CD8 T Cell Requirements for Anti-PD-1 Versus Anti-CTLA-4.
IL-9 signaling redirects CAR T cell fate toward CD8+ memory and CD4+ cycling states, enhancing antitumor efficacy.
Disruption of metabolic licensing by JAK inhibitors constrains CD8 T cell activation and effector function.
Defined metabolic states shape T cell fate and function across culture conditions.
Inhibitory PD-1 axis maintains high-avidity stem-like CD8+ T cells.
Rroid2 regulates effector-to-memory CD8+ T cell differentiation during infection in vivo.
Autophagy disruption primes CAR-T cell metabolism for sustained rejection of ovarian tumors.
Robust PD-1 blockade compromises clonal affinity of stem-like CD8+ T cells.
Mitochondria redistribution organizes the immunosuppressive tumor ecosystem.
Functional heterogeneity and plasticity in naïve CD8 T cells drive superior effector and memory responses.
Piezo1-mediated mechano-energetics regulate CAR T cell function.
Immune Age, Cardiovascular Disease, and Anti-Viral Immunity.
Engineered Dendritic Cell-Derived Vesicles for T-Cell-Targeted Magnesium Delivery and Metabolic Reprogramming.
Enhancement of suppressive function of Ly49+ CD8+ T cells in allogeneic immunity by CD80/86-CD28 blockade in mouse.
Pre-division TCF1 drop determines long-term CD8 T cell fates.
OCA-B/Pou2af1 Expression in Mouse T Cells Promotes PD-1 Blockade-Induced Autoimmunity but is Dispensable for Anti-Tumor Immunity.
Anti-uPAR CAR T cells reverse and prevent aging-associated defects in intestinal regeneration and fitness.
Inhibition of PKCθ Abrogates CD8+ T Cell-Mediated Neurotoxicity in Murine Cerebral Malaria.
Breastfeeding induces protective T cells.
CD8 + T cell recall cytotoxicity during chronic treated HIV-1 infection is associated with limited reservoir size and activity.
LCMV-mediated loss of virtual memory CD8 T cells yields a functionally enhanced T cell subset.
Scalable transcription factor mapping uncovers the regulatory dynamics of natural and synthetic transcription factors in human T cell states.
Divergent role of CD8 T cells with distinct metabolic phenotypes during curative radio-immunotherapy in hot versus cold tumors.
Targeting tumor-draining lymph node to overcome resistance to cancer immunotherapy: an update.

Dev Cell. 2025 Nov 27. pii: S1534-5807(25)00691-4. [Epub ahead of print]

Vitamin B6 preserves the stemness-like phenotypes and antitumor ability of CD8+ T cells.

Jun Wu, Gen Li, Jiawen Zhou, Xuan Sun, Haoyu Wang, Haipeng Gong, Peng Jiang.

  Tumor-infiltrating lymphocytes are usually dysfunctional but demonstrate stem cell-like behavior through unclear mechanisms. Here, we report that administration of vitamin B6 or its active form, pyridoxal phosphate (PLP), endows mouse and human CD8+ T cells with improved persistence, stemness-like phenotypes, and tumor clearance capabilities. Lowering PLP by pyridoxal kinase (PDXK) heterozygosity results in reduced T cell stemness-like properties and increased exhaustion phenotypes in tumors. Mechanistically, PLP preserves T cell function by directly binding to and inhibiting p70S6 kinase (p70S6K). Through limiting p70S6K-mediated BTB domain and CNC homolog 2 (BACH2) phosphorylation, PLP increases nuclear retention and functional activation of BACH2, promoting stemness gene expression while dampening exhaustion gene expression. In preclinical tumor models, PLP treatment improves the efficacy of anti-programmed death receptor 1 (PD-1) antibody therapy. Thus, our study reveals a pathway that preserves T cell functional stemness-like phenotypes to drive the acquisition of antitumor immunity, highlighting the clinical potential of vitamin B6/PLP-enhanced T cell function strategies in cancer immunotherapy.

Keywords:  T cell differentiation; antitumor immunity; metabolite signaling; p70S6K; vitamin B6

DOI:  https://doi.org/10.1016/j.devcel.2025.10.017
bioRxiv. 2025 Oct 13. pii: 2025.10.10.681497. [Epub ahead of print]

Bhlhe40 Coordinates T Cell Programs with Distinct CD4 and CD8 T Cell Requirements for Anti-PD-1 Versus Anti-CTLA-4.

Akata Saha, Tomoyuki Minowa, Alexander S Shavkunov, Avery J Salmon, Sunita Keshari, Nicholas N Jarjour, Kristen E Pauken, Kenneth H Hu, Brian T Edelson, Ken Chen, Matthew M Gubin.

The transcriptional programs that enable CD4 and CD8 T cells to mediate effective anti-tumor immunity remain incompletely defined. Here, we identify distinct, therapy-specific roles for the transcriptional regulator Bhlhe40 in CD4 and CD8 T cells, revealing divergent requirements during anti-PD-1 versus anti-CTLA-4 immune checkpoint therapy (ICT). Using conditional knockout mice, we show that anti-PD-1 efficacy depends on CD8 T cell-intrinsic Bhlhe40 and may also require its expression in CD4 T cells, whereas anti-CTLA-4 relies primarily on CD4 T cell-intrinsic Bhlhe40 and remains effective without Bhlhe40 in CD8 T cells. Loss of Bhlhe40 skews CD8 T cells toward TCF-1-expressing naïve and progenitor exhausted-like states, particularly in the absence of ICT. Bhlhe40 sustains CD8 effector and exhausted phenotypes, promotes IFN-γ production, and supports glycolytic and mitochondrial programs, with Bhlhe40 deficiency leading to impaired glycolysis under either anti-PD-1 or anti-CTLA-4 ICT, and reduced mitochondrial function primarily during anti-PD-1. In addition, CD8 T cell-intrinsic Bhlhe40 is required for full ICT-induced remodeling of the tumor myeloid compartment from CX3CR1⁺ macrophages to iNOS⁺ macrophages. In contrast, anti-CTLA-4 can drive tumor rejection and partial macrophage remodeling in the absence of CD8 T cell-intrinsic Bhlhe40, provided CD4 T cell function is intact. Analysis of human cancer datasets revealed that BHLHE40 is enriched in tumor-reactive and activated/exhausted CD8 T cells, where its expression is inversely correlated with TCF7 (TCF-1) and positively associated with TOX and IFNG . Moreover, subsets of CD8 T cells expressed higher levels of BHLHE40 in basal and squamous cell carcinoma responders compared with non-responders. Together, these findings establish Bhlhe40 not only as a transcriptional coordinator of T cell effector programs and metabolic fitness, but also as a therapy-specific, subset-dependent determinant of ICT efficacy, providing a mechanistic basis for the divergent modes of action of anti-PD-1 versus anti-CTLA-4.
HIGHLIGHTS: Bhlhe40 is essential in CD8 T cells for anti-PD-1 ICT, but dispensable for anti-CTLA-4 due to compensatory CD4 T cell function CD8 T cell-intrinsic Bhlhe40 drives effector/exhausted states over TCF-1 + naïve and progenitor-exhausted like phenotypes Bhlhe40 sustains T cell metabolic fitness, supporting glycolysis under both therapies and OXPHOS primarily during anti-PD-1CD8 T cell-intrinsic Bhlhe40 is required for full ICT-driven macrophage remodeling In human cancers, Bhlhe40 is enriched in tumor-reactive CD4 and CD8 T cells, positively linked to TOX / IFNG and inversely to TCF7 (TCF-1).

DOI: https://doi.org/10.1101/2025.10.10.681497
Immunity. 2025 Nov 21. pii: S1074-7613(25)00475-3. [Epub ahead of print]

IL-9 signaling redirects CAR T cell fate toward CD8+ memory and CD4+ cycling states, enhancing antitumor efficacy.

Sofía Castelli, Wesley V Wilson, Ugur Uslu, Amanda V Finck, Philipp C Rommel, Charles-Antoine Assenmacher, Sebastian J Atoche, Mikko Siurala, M Angela Aznar, Regina M Young, Carl H June.

  The success of chimeric antigen receptor (CAR) T cell therapies targeting solid tumors is limited by the immunosuppressive tumor microenvironment. We demonstrate that endowing CAR T cells with ectopic interleukin (IL)-9 signaling by co-expressing an IL-9 receptor rewires CAR T cell fate under antigen stress to enhance antitumor efficacy. In preclinical solid tumor models, IL-9-signaling CAR T cells exhibit increased expansion, persistence, and tumor infiltration, resulting in superior tumor control at substantially lower doses than conventional products. Trajectory and RNA velocity analyses of single-cell RNA sequencing data reveal that IL-9 signaling alters CAR T cell differentiation under antigen stress away from dysfunction, favoring a multipotent transition toward CD8+ T cell memory and effector states and promoting a CD4+ cell proliferative state. Interrogation of transcription factor pathways indicates that IL-9-mediated activation of STAT1 and STAT4 may contribute to the superior phenotype of IL-9-signaling CAR T cells, providing a promising therapeutic strategy for targeting solid cancers.

Keywords:  CAR T cells; IL-9; IL-9R; T cell dysfunction; T cell memory; cancer immunotherapy; cytokine receptors; cytokines; solid tumors

DOI:  https://doi.org/10.1016/j.immuni.2025.10.021
Res Sq. 2025 Oct 27. pii: rs.3.rs-7794494. [Epub ahead of print]

Disruption of metabolic licensing by JAK inhibitors constrains CD8 T cell activation and effector function.

Eva Acosta Rodriguez, Luisina Onofrio, Carolina Abrate, Ingrid Strusberg, Liliana Morales, Danilo Ceschin, Carolina Montes, Cinthia Stempin.

Janus kinase inhibitors (JAKis) are widely prescribed for autoimmune diseases, but their use is associated with increased infection risk. The mechanisms underlying this susceptibility remain unclear. CD8 T cells play a central role in antimicrobial defense, yet little is known about how JAKis reprogram their activation and effector programs. Here, we investigated naïve and memory CD8 T cells from healthy donors stimulated in vitro with baricitinib, tofacitinib, or upadacitinib. Flow cytometry, SCENITH, transmission electron microscopy, and RNA-seq were used to evaluate metabolic and functional programs. We found that JAKis uncoupled phenotypic activation from metabolic reprogramming. Functionally, JAKi-treated CD8 T cells exhibited reduced activation and produced lower amounts of cytokines and cytotoxic molecules. Notably, even JAKi-treated memory CD8 T cells that upregulated CD69 and CD25 failed to engage glycolysis, showing decreased GLUT1 expression and glucose uptake. SCENITH profiling confirmed diminished glucose dependence and a shift toward mitochondrial reliance, despite reduced mitochondrial potential and structural alterations. Transcriptomic and protein analyses further revealed decreased mTOR activity and increased p53-associated transcripts, consistent with impaired growth and stress signaling. CD8 T cells from rheumatoid arthritis patients under JAKi therapy were analyzed ex vivo for translational validation. These cells showed similar metabolic and signaling alterations, underscoring their clinical relevance. Altogether, these findings identify JAKis as disruptors of metabolic and signaling pathways in CD8 T cells, providing a mechanistic link between impaired effector function and the increased infection risk observed in treated patients.

DOI: https://doi.org/10.21203/rs.3.rs-7794494/v1
Front Immunol. 2025 ;16 1703095

Defined metabolic states shape T cell fate and function across culture conditions.

Kayla Sylvester, Natasha Karassina, Anthony C Lauer, Gediminas Vidugiris, Jolanta Vidugiriene.

   Introduction: T cell metabolism is a key determinant of immune function and therapeutic efficacy, yet current expansion protocols often neglect how culture conditions influence metabolic programming. We employed a modular, low-input bioluminescent assay platform to profile how media, activation strength, and metabolic perturbation define metabolic trajectories that persist through early expansion and influence downstream outcomes.
Methods: A multifactorial experimental design was used to evaluate early T-cell activation across media (ICXF, TexMACS, RPMI+FBS) and activators (TransAct, Dynabeads, ImmunoCult). Low-input bioluminescent assays were used to quantify metabolic cofactors (ATP, NAD+, NADP(H)), reducing capacity, and nutrient usage (glucose, lactate, malate). Conditions that yield metabolically distinct phenotypes were selected for deeper analysis of proliferation, cytokine secretion, cytotoxicity, and flow cytometric profiling. To validate and functionally confirm these phenotypes, pathway-specific metabolic inhibitors were introduced in follow-up experiments.
Results: By measuring intracellular ATP, NAD+, NADP(H), reducing capacity, and nutrient flux, we identified media- and activation-specific metabolic states that emerged upon T-cell activation and persisted through early expansion. ICXF with TransAct promoted a glycolytic, NAD-rich phenotype associated with rapid expansion. In contrast, TexMACS with ImmunoCult supported oxidative metabolism, enriched for TSCM-like cells, and enhanced cytotoxicity despite slower growth. Early lactate levels strongly predicted downstream expansion (r = 0.68, p < 0.0001), highlighting glycolytic activity as a key determinant of proliferative potential. Functional validation with pathway-specific inhibitors revealed media-dependent vulnerabilities, highlighting distinct metabolic wiring.
Conclusion: This approach enables predictive, multiplexed metabolic profiling using minimal sample input and offers a scalable strategy to optimize T-cell manufacturing for memory enrichment and cytotoxic potency.

Keywords:  T cell metabolism; adoptive cell therapy; bioluminescent assays; ex vivo expansion; glycolysis; immunometabolism; memory T cells; metabolic profiling

DOI:  https://doi.org/10.3389/fimmu.2025.1703095
Nature. 2025 Nov 26.

Inhibitory PD-1 axis maintains high-avidity stem-like CD8+ T cells.

Jyh Liang Hor, Edward C Schrom, Abigail Wong-Rolle, Luke Vistain, Wanjing Shang, Qiang Dong, Chen Zhao, Chengcheng Jin, Ronald N Germain.

Stem-like progenitors are self-renewing cytotoxic T cells that expand as effector cells during successful checkpoint immunotherapy1,2. Emerging evidence suggests that tumour-draining lymph nodes support the continuous generation of these stem-like cells that replenish tumour sites and are a key source of expanded effector populations3-6, underlining the importance of understanding what factors promote and maintain activated T cells in the stem-like state. Here, using advanced three-dimensional multiplex immunofluorescence imaging, we identify antigen-presentation niches in tumour-draining lymph nodes that support the expansion, maintenance and affinity evolution of TCF-1+PD-1+SLAMF6high stem-like CD8+ T cells. Contrary to the prevailing view that persistent T cell receptor (TCR) signalling drives terminal effector differentiation, prolonged antigen engagement days beyond initial priming sustains the proliferation and self-renewal of these stem-like T cells in vivo. The inhibitory PD-1 pathway has a central role in this process through fine-tuning the TCR signal input that enables the selective expansion of high-affinity TCR stem-like clones as a renewable source of effector cells. PD-1 blockade disrupts this tuning, leading to terminal differentiation or death of the most avid anti-tumour stem-like cells. Our results therefore reveal a relationship between TCR ligand affinity recognition, a key negative-feedback regulatory loop and T cell stemness programming. Furthermore, these findings raise questions about whether anti-PD-1 blockade during cancer immunotherapy provides a short-term anti-tumour effect at the cost of diminishing efficacy due to progressive loss of these critical high-affinity precursors.

DOI: https://doi.org/10.1038/s41586-025-09440-x
Proc Natl Acad Sci U S A. 2025 Dec 02. 122(48): e2503450122

Rroid2 regulates effector-to-memory CD8+ T cell differentiation during infection in vivo.

Julia Erber, Carmen Stecher, Valerie Plajer, Nina Braun, William Mallard, Loyal A Goff, Iros Barozzi, Thomas Mohr, John L Rinn, Richard A Flavell, Dietmar Herndler-Brandstetter.

  CD8+ T cell differentiation has been associated with changes in the expression of long noncoding RNAs (lncRNAs). Yet, which and how lncRNAs regulate CD8+ T cell responses following infection in vivo remains incompletely understood. We performed deep RNA-seq to map the lncRNA expression landscape of CD8+ T cell subsets during infection and generated lncRNA knockout mouse models to evaluate the in vivo relevance of six lncRNAs. We identified Rroid2 to regulate effector CD8+ T cell function and effector-to-memory differentiation. Rroid2-deficient mice displayed increased CD44dim Foxp3+ regulatory T cells while the development of other immune cells, such as natural killer cells, was not affected. In CD8+ T cells, Rroid2 deficiency resulted in a fine-tuned downregulation of transcription factors Id2 and T-bet and impaired KLRG1+ and KLRG1- effector CD8+ T cell proliferation and cytotoxicity as well as effector-to-memory CD8+ T cell differentiation. The human orthologue of Rroid2, LINC01814, is also upstream of the transcriptional regulator ID2 and is highly expressed in human memory CD8+ T cells. Taken together, Rroid2 represents a key regulatory layer that controls CD8+ T cell differentiation.

Keywords:  CD8 T cell differentiation; cytotoxic T cell; infection; knockout mouse model; long noncoding RNA

DOI:  https://doi.org/10.1073/pnas.2503450122
bioRxiv. 2025 Oct 10. pii: 2025.10.09.681473. [Epub ahead of print]

Autophagy disruption primes CAR-T cell metabolism for sustained rejection of ovarian tumors.

Gillian A Carleton, Sébastien Levesque, Lauren G Zacharias, Joao San Patricio, Tracey Sutcliffe, Peter H Watson, Ralph J DeBerardinis, Yannick Doyon, Julian J Lum.

T-cell based immunotherapies such as chimeric antigen receptor T (CAR-T) cell therapy face substantial hurdles when confronting solid tumors such as ovarian cancer, where metabolic constraints in the tumor microenvironment limit T cell infiltration and function. In particular, T cells exposed to nutrient deprivation and hypoxia upregulate autophagy, a lysosomal degradation pathway that negatively regulates effector responses. Here, we used CRISPR-Cas9 to target a folate receptor alpha (αFR) CAR expression cassette into the locus of the essential autophagy gene ATG5, thereby generating autophagy-deficient CAR-T cells in a single editing step. Targeted metabolite profiling revealed that deletion of ATG5 induced widespread metabolic reprogramming characterized by increased glucose and amino acid uptake. Functionally, ATG5-knockout CAR-T cells maintained high cytolytic activity when assayed in patient-derived ascites in vitro, and exhibited superior and long-lasting tumor control against ovarian tumors in vivo. Taken together, our results suggest that deletion of ATG5 metabolically primes CAR-T cells for enhanced cytotoxicity in immune-suppressive conditions, thereby improving the therapeutic potential of αFR CAR-T cells for ovarian cancer immunotherapy.

DOI: https://doi.org/10.1101/2025.10.09.681473
Immunol Cell Biol. 2025 Nov 27.

Robust PD-1 blockade compromises clonal affinity of stem-like CD8+ T cells.

Carlson Tsui, Michael H Shannon.

DOI: https://doi.org/10.1111/imcb.70062
bioRxiv. 2025 Nov 13. pii: 2025.11.11.687895. [Epub ahead of print]

Mitochondria redistribution organizes the immunosuppressive tumor ecosystem.

Azusa Terasaki, Alexis T Weiner, Yuhao Tan, Viktoria Szeifert, Keshav Bhatnagar, Cara C Rada, Vishnu Shankar, Courtney Kernick, Mahnoor Mahmood, Lukas Wiggers, Viviana R Rodrigues, Payam A Gammage, Theodore Roth, Jeffrey D Axelrod, Edgar Engleman, Bo Li, Derick Okwan-Duodu.

Hostile conditions in the tumor microenvironment restrict cellular respiration, yet mitochondrial metabolism remains indispensable for tumor growth and the activity of immunosuppressive cells. How tumor ecosystems sustain mitochondrial output has been unclear. Here, we show that cancer cells resolve this paradox by acting as hubs of intercellular mitochondrial redistribution. Using mitochondrial reporter systems, we demonstrate that cancer cells import host-derived mitochondria, integrate them into their endogenous network, and subsequently relay these hybrid organelles to neighboring immune cells. Mitochondria redistribution reprograms recipient neutrophils, macrophages, and CD4+ T cells into highly suppressive states but drives CD8+ T cell exhaustion. Within cancer cells, fusion of incoming mitochondria induces filamentous P5CS assembly, enhances biosynthetic output, and enables the refurbishment of damaged organelles into fully functional units. Disrupting mitochondrial redistribution collapses the immunosuppressive ecosystem and impairs tumor growth. Thus, cancer cells do not hoard resources but orchestrate a redistribution program that fortifies their own metabolic resilience, derails anti-tumor immunity, and sustains immunosuppressive partners.
HIGHLIGHTS: Tumor cells regulate their ecosystem by redistributing mitochondriaRedistributed mitochondria expand immunosuppressive cells but exhausts CD8+ T cellsMitochondria fusion within cancer cells, which precedes redistribution, optimizes metabolic output by triggering conformational changes in P5CSMitochondria fusion allows cancer cells to incorporate and refurbish seemingly incompetent host-derived mitochondria, improving efficiency in the tumor ecosystem.

DOI: https://doi.org/10.1101/2025.11.11.687895
bioRxiv. 2025 Oct 17. pii: 2025.10.16.682909. [Epub ahead of print]

Functional heterogeneity and plasticity in naïve CD8 T cells drive superior effector and memory responses.

Yamato Sajiki, Satomi Ando, Charles M Perkins, Yi-Chung Huang, Katie E Smith, Carolyn M Doerning, Koichi Araki.

While significant progress has been made in defining subsets among antigen-experienced CD8 T cells, the heterogeneity of naïve CD8 T cells remains poorly understood. Here, we identify naïve CD8 T cell subsets with superior persistence and an enhanced capacity to generate effector and memory cells, leading to more effective protection. These high-quality naïve CD8 T cells are marked by IL-18Rα, CD73, and CXCR3, and functionally less potent naïve CD8 T cells can convert into these superior subsets. Their enhanced response to infections is driven by better survival of the progeny effector cells during the T cell expansion phase. This improved survival is mediated by increased Ly6C2 expression on effector cells derived from these high-quality naïve cells. Collectively, our findings reveal functional heterogeneity and plasticity among naïve CD8 T cells and uncover a mechanism by which high-quality naïve subsets drive robust CD8 T cell responses, providing a previously unrecognized layer of immune regulation.

DOI: https://doi.org/10.1101/2025.10.16.682909
Res Sq. 2025 Oct 23. pii: rs.3.rs-7776704. [Epub ahead of print]

Piezo1-mediated mechano-energetics regulate CAR T cell function.

Weiqiang Chen, Ngoc Luu, Rui Li, Yifei Fang, Huishu Wang, Yujing Song, Ruiqi Chen, Xiangyi Fang, Junru Liao, Katsuo Kurabayashi, Roddy O'Connor, Louis Hodgson, Saba Ghassemi, Tracy Chen, Andre Kelly, Alexander Shestov.

CAR T cell cytotoxicity requires generating immense mechanical force, but the energetic costs of this process remain poorly defined. While metabolic reprogramming fuels effector function, its mechanistic connection to mechanotransduction remains unclear. By directly measuring the synaptic force and mechanical energy of single CAR T cells and linking them to their metabolic state, we proved that the mechano-energetic efficiency is a fundamental determinant of cytotoxic potency. We discovered that the mechanosensitive ion channel Piezo1 couples cytoskeletal dynamics to metabolic rewiring via Ca²⁺-Wnt-Rac1 signaling. Disrupting Piezo1 cripples glycolytic and mitochondrial ATP production, causing energetic stress and impaired cytotoxicity. Notably, Piezo1 activity follows a Goldilocks principle: intermediate level maximizes activation and cytotoxicity, whereas either hypoactive or hyperactive Piezo1 states impair mechano-metabolic fitness and drive dysfunction in patient and exhausted CAR T cells. Our work establishes mechano-metabolic coupling as a core regulator of CAR T cell fitness and pinpoints Piezo1 tuning as a new strategy to enhance cancer immunotherapy. .

DOI: https://doi.org/10.21203/rs.3.rs-7776704/v1
Cells. 2025 Nov 14. pii: 1793. [Epub ahead of print]14(22):

Immune Age, Cardiovascular Disease, and Anti-Viral Immunity.

Kevin-Phu C Le, Fahad Shuja, Jorg J Goronzy, Cornelia M Weyand.

  Cardiovascular morbidity and mortality rise precipitously during the 6th-9th decades of life, identifying aging as a critical risk factor. Simultaneously, older individuals are susceptible to severe viral infection, raising the question whether shared mechanisms exist that predispose to both cardiovascular disease (CVD) and failing anti-viral immunity. The aging process causes steady decline in immune fitness (immune aging), which undermines the ability to generate protective anti-viral immune responses. Paradoxically, the aging immune system supports unopposed inflammatory pathways (inflammaging), which exacerbates tissue inflammation in CVD, specifically atherosclerosis. Here, we review the current evidence of how innate and adaptive immune aging promotes tissue-destructive inflammation in atherosclerosis while failing to fight viral infections. Further, we consider how these two disease processes mutually influence each other. We propose that mounting an effective anti-viral response induces off-target bystander activation and exhausts immune cells, ultimately exacerbating CVD. Additionally, we explore how atherosclerotic CVD impacts innate immunity through epigenetic modification of hematopoietic precursors and metabolically conditioning immune cells, leading to a dysfunctional immune system that accelerates plaque inflammation while simultaneously impairing host defense.

Keywords:  B cell aging; DNA methylation; T cell aging; atherosclerosis; cardiovascular disease; hematopoietic stem cell; immune checkpoint; macrophage aging; viral infection

DOI:  https://doi.org/10.3390/cells14221793
ACS Nano. 2025 Nov 25.

Engineered Dendritic Cell-Derived Vesicles for T-Cell-Targeted Magnesium Delivery and Metabolic Reprogramming.

Xiaoyu Yu, Shuqi Chen, Rong Sun, Chenlu Yao, Bingbing Wu, Heng Wang, Chenhui Weng, Dongdong Sun, Chao Wang, Fang Xu.

  The tumor microenvironment (TME) fosters immunosuppression and T-cell exhaustion, which limit the efficacy of immunotherapy. Magnesium ions (Mg2+) have recently been identified as potent immunomodulators that enhance cytotoxic T lymphocyte (CD8+ T) activity. However, conventional carriers for Mg2+ delivery suffer from poor biocompatibility and inefficient targeting, restricting therapeutic outcomes. In this study, we developed an engineered extracellular vesicle (EV)-based system for targeted Mg2+ delivery. Dendritic cells were genetically modified to overexpress magnesium-specific channel protein MgtE (SLC41A1), enabling efficient Mg2+ encapsulation into dendritic cell-derived EVs (E-DEVs). The resulting Mg2+-loaded vesicles (E-DEVs@Mg2+) displayed strong tropism toward tumor-draining lymph nodes (TDLNs) and effectively modulated T-cell metabolism. Mechanistic studies revealed that E-DEVs@Mg2+ enhanced glycolysis and oxidative phosphorylation, restoring the metabolic fitness of exhausted CD8+ T cells. When combined with immune checkpoint blockade therapy, this strategy achieved a synergistic tumor suppression. Our findings highlight engineered DEVs as a biocompatible and effective Mg2+ delivery platform, providing a promising approach for metabolic reprogramming and improved cancer immunotherapy.

Keywords:  Immunoengineering; dendritic cells; extracellular vesicles; immunotherapy technology; magnesium ions

DOI:  https://doi.org/10.1021/acsnano.5c14528
J Heart Lung Transplant. 2025 Nov 24. pii: S1053-2498(25)02405-2. [Epub ahead of print]

Enhancement of suppressive function of Ly49+ CD8+ T cells in allogeneic immunity by CD80/86-CD28 blockade in mouse.

Koji Tokushige, Yin Enzhi, Kyoko Tsuji-Yogo, Gong Yu, Kodai Morimoto, Kyohei Kuriyama, Masato Kubo, Hideo Yagita, Jiro Kitaura, Ko Okumura, Kazuyoshi Takeda, Koichiro Uchida.

   BACKGROUND: Ly49⁺ CD8⁺ T cells restricted by Qa-1 or major histocompatibility complex (MHC)/peptide can function as immune suppressors in autoimmune diseases and chronic activation-associated tissue damage. In organ transplantation, a C-X-C motif chemokine receptor 5+ (CXCR5⁺) Ly49⁺ CD8⁺ T cell subset reportedly suppresses CD4⁺ T cell activation via Qa-1 recognition, thereby inhibiting donor-specific antibody (DSA) production and promoting heart graft survival, particularly under CD80/86-CD28 co-stimulation blockade. However, their precise role in anti-allogeneic responses remains unclear.
METHODS: We examined Ly49⁺ CD8⁺ T cell function in a murine cardiac transplant model and mixed lymphocyte reactions (MLRs), with or without antagonistic anti-CD80/86 monoclonal antibodies (mAbs).
RESULTS: Both Ly49⁺ and Ly49- CD8⁺ T cells infiltrated grafts and produced IFN-γ. Anti-CD80/86 mAb treatment prolonged graft survival, reduced IFN-γ production, increased infiltration of cytotoxic Ly49⁺ CD8⁺ T cells, and upregulated immunosuppressive gene expression in accepted grafts. In MLRs, Ly49⁺ CD8⁺ T cells showed greater proliferation and IFN-γ production than Ly49- counterparts. Qa-1 blockade had no effect, whereas anti-CD80/86 mAb induced anergy. Ly49⁺ CD8⁺ T cells obtained after MLR with anti-CD80/86 mAbs were hyporesponsive to restimulation but exerted enhanced cytotoxicity against activated autologous T cells partly via Qa-1 interaction. Furthermore, these Ly49+ CD8+ T cells expressed lymphocyte activation gene-3 (LAG-3) and cytotoxic T-lymphocyte associated antigen 4 (CTLA-4), which contributed to the suppression of T cell proliferation.
CONCLUSION: Ly49⁺ CD8⁺ T cells function as effectors in anti-allogeneic responses. CD80/86-CD28 blockade suppresses their effector functions while enhancing their Qa-1-dependent regulatory activity toward activated autologous T cells.

Keywords:  CD80/86-CD28; CTLA-4; LAG-3; Ly49+CD8+ T cell; immune suppression

DOI:  https://doi.org/10.1016/j.healun.2025.11.017
bioRxiv. 2025 Oct 06. pii: 2025.10.06.680655. [Epub ahead of print]

Pre-division TCF1 drop determines long-term CD8 T cell fates.

Natalie R Favret, Maider Astorkia, Melissa M Wolf, Michael W Rudloff, Claudia N McDavid, Megan M Erwin, Kristen A Murray, Jessica J Roetman, Carlos R Detrés Román, Zachary D Ewell, Lincoln A Brown, William T Murray, Paul Zumbo, Doron Betel, Mary Philip.

T Cell Factor 1 (TCF1) is a master transcription factor controlling T cell development and peripheral T cell differentiation during infection, cancer, and autoimmunity. TCF1 is highly expressed in naive CD8 T cells but must be downregulated as T cells proliferate to become effectors. If and how TCF1 plays a role during T cell priming prior to cell cycle entry is unknown. Surprisingly, we found that TCF1 expression is rapidly downregulated within hours after antigen encounter in both murine and human CD8 T cells, even before T cells enter cell cycle. TCF1 then rebounds to high levels upon cell cycle entry, ultimately declining again with proliferation and effector differentiation. This rapid pre-division drop and rebound occurs in diverse settings, including infection and cancer. The magnitude of the pre-division TCF1 drop is modulated by TCR signal strength and inflammatory cytokines and strikingly, regulates long-term effector and memory fates. Paired transcriptomic and epigenetic analyses revealed that TCF1-regulated chromatin regions were remodeled within hours following antigen encounter, activating effector and inflammatory cytokine signaling modules and poising T cells for effector differentiation. Remarkably, transient siRNA-mediated TCF1 downmodulation during the pre-division priming phase was sufficient to induce long-term population effector skewing. We have uncovered a novel mechanism whereby pre-division dynamic TCF1 regulation determines long-term CD8 T cell fate commitment, potentially serving as a critical checkpoint regulating T cell responses in infection, cancer, and autoimmunity.

DOI: https://doi.org/10.1101/2025.10.06.680655
bioRxiv. 2025 Oct 23. pii: 2025.10.22.683978. [Epub ahead of print]

OCA-B/Pou2af1 Expression in Mouse T Cells Promotes PD-1 Blockade-Induced Autoimmunity but is Dispensable for Anti-Tumor Immunity.

Junhong Du, Asit K Manna, Erik P Hughes, Paulla Bisoma, Kimberley J Evason, Arabella Young, W David Wilson, Abdelbasset A Farahat, Dean Tantin.

The transcription coregulator OCA-B promotes CD4 + T cell memory recall responses and autoimmunity. OCA-B T cell deletion blocks spontaneous T1D onset in non-obese diabetic (NOD) mice and blunts T1D in a subset of more aggressive models. However, the role of OCA-B in diabetes induced by treatment with checkpoint blockade therapies, and the role of OCA-B in the control of tumors with and without α-PD-1 treatment, has not been studied. We show that deletion of OCA-B in T cells fully insulates 8-week-old non-obese diabetic (NOD) mice against α-PD-1 antibody-induced diabetes induction and partially protects 12-week-old mice. Salivary/lacrimal gland infiltration and inflammation were also reduced. Protection was associated with a block in the differentiation of progenitor exhausted CD8 + T cells (T PEX ) into terminally exhausted CD8 + T cells (T EX ). We show that OCA-B T cell loss preserves anti-tumor immune responses following PD-1 blockade therapy in a variety of tumor cell lines. These findings point to a potential therapeutic window in which pharmaceuticals that target OCA-B could be used to block the emergence of both spontaneous and checkpoint blockade-induced autoimmunity while minimally affecting anti-tumor immune responses. We develop first-in-class small molecule inhibitors of Oct1/OCA-B transcription complexes and show that administration into NOD mice also blocks diabetes emergence following α-PD-1 treatment. These results identify OCA-B as a promising therapeutic target for the prevention of autoimmunity and immune-related adverse events (irAEs).

DOI: https://doi.org/10.1101/2025.10.22.683978
Nat Aging. 2025 Nov 25.

Anti-uPAR CAR T cells reverse and prevent aging-associated defects in intestinal regeneration and fitness.

Onur Eskiocak, Joseph Gewolb, Vyom Shah, James A Rouse, Saria Chowdhury, Erdogan O Akyildiz, Inés Fernández-Maestre, Jacob A Boyer, Aveline Filliol, Alexander S Harris, Raditya Utama, Guangran Guo, Carolina Castro-Hernández, Emmanuella Nnuji-John, Charlie Chung, Arianna Anderson, Sara Flowers, Jill Habel, Paul B Romesser, Ross L Levine, Scott W Lowe, Michel Sadelain, Semir Beyaz, Corina Amor.

Intestinal stem cells (ISCs) drive the rapid regeneration of the gut epithelium. However, during aging, their regenerative capacity wanes, possibly through senescence and chronic inflammation, albeit little is known about how aging-associated dysfunction arises in the intestine. We previously identified the urokinase plasminogen activator receptor (uPAR) as a senescence-associated protein and developed CAR T cells able to efficiently target it. Harnessing them, here, we identify the accumulation of mostly epithelial uPAR-positive cells in the aging gut and uncover their detrimental impact on ISC function in aging. Thus, both therapeutic and prophylactic treatment with anti-uPAR CAR T cells improved barrier function, regenerative capacity, inflammation, mucosal immune function and microbiome composition in aged mice. Overall, these findings reveal the deleterious role of uPAR-positive cells on intestinal aging in vivo and provide proof of concept for the potential of targeted immune-based cell therapies to enhance tissue regeneration in aging organisms.

DOI: https://doi.org/10.1038/s43587-025-01022-w
Biomedicines. 2025 Oct 22. pii: 2582. [Epub ahead of print]13(11):

Inhibition of PKCθ Abrogates CD8+ T Cell-Mediated Neurotoxicity in Murine Cerebral Malaria.

Karin Albrecht-Schgör, Victoria E Stefan, Martina Steinlechner, Dominik Humer, Kerstin Siegmund, Sebastian Peer, Thomas Gruber, Maja Überegger, Stephanie Zur Nedden, Gabriele Baier-Bitterlich, Peter Lackner, Erich Schmutzhard, Nikolaus Thuille, Victoria Klepsch, Gottfried Baier.

  Background: Cerebral malaria (CM) is a severe and often fatal complication of Plasmodium falciparum infection that causes devastating brain injury largely through immune-mediated mechanisms. Pathogenic brain-infiltrating CD8+ T cells are key drivers of CM pathology, yet the intracellular signals enabling their harmful autoimmune-like activity remain poorly defined. Here, we identify protein kinase C θ (PKCθ), a central antigen receptor-signalling mediator, as a critical contributor to experimental cerebral malaria (ECM). Methods/Results: Using a PKCθ null allele mouse strain on a C57BL/6N background, we demonstrate that PKCθ deficiency significantly improves survival in Plasmodium berghei ANKA (PbA)-infected mice without altering parasite burdens in the blood or brain. Mechanistically, loss of PKCθ skews T cell differentiation towards central memory (Tcm) rather than effector memory (Tem) phenotypes, thereby reducing effector differentiation and sequestration of CD8+ T cells in the cerebral microvasculature. This prevents extensive neurovascular damage, preserves neural tissue integrity, and alleviates neurological signs and symptoms. Our findings provide genetic evidence that PKCθ drives CD8+ T cell-mediated brain injury in ECM. Conclusions: These results underscore the potential for repurposing clinically PKCθ inhibitors as host-targeted interventions to protect against cerebral injury and improve outcomes in patients with CM.

Keywords:  CD8+ T cells; cerebral malaria (CM); drug repurposing; experimental cerebral malaria (ECM); host-targeted candidate therapy; immune-mediated brain injury; neurovascular damage; protein kinase C-θ (PKCθ)

DOI:  https://doi.org/10.3390/biomedicines13112582
Nat Immunol. 2025 Dec;26(12): 2117

Breastfeeding induces protective T cells.

Stephanie Houston.

DOI: https://doi.org/10.1038/s41590-025-02362-w
medRxiv. 2025 Oct 13. pii: 2025.10.10.25337688. [Epub ahead of print]

CD8 + T cell recall cytotoxicity during chronic treated HIV-1 infection is associated with limited reservoir size and activity.

David R Collins, Mpho J Olatotse, Jonathan M Urbach, Zhu Zhuo, Suhui Zhao, Tyler J Lilie, Rachel Raymond, Xianbao He, James Y Chen, Bridget Coffey, Umar Arshad, Zachary J Racenet, Hannah Wisner, Carlos Casquero, Xuan Guo, Lucy C Walters, Jennifer M Davis, Hannah C Jordan, Noor Sohail, Kiera L Clayton, Manish Sagar, James Billingsley, Shannan Ho Sui, Emanuele Mazzola, Bruce D Walker, Athe Tsibris.

The combination of replication-competent HIV-1 proviral persistence and virus-specific immune dysfunction prevents virus clearance during antiretroviral therapy (ART), resulting in rebound viremia after treatment interruption. Functional impairment of HIV-specific CD8 + T cells during chronic infection is typically not reversed by ART but has recently been shown to improve in some individuals after prolonged treatment. To evaluate the impact of cellular immune function on viral persistence, we mapped and functionally characterized HIV-1 epitope-specific CD8 + T cell responses and virus reservoirs in sixty people with HIV-1 (PWH) who initiated prolonged ART during chronic progressive infection. In 17% of participants, recall cytotoxicity of proliferative CD8 + T cells targeting one or more autologous proviral epitopes was comparable to responses in spontaneous HIV-1 controllers. These responses were associated with smaller and less transcriptionally active HIV-1 reservoirs during prolonged ART. Treatment interruption in one participant with moderately high HIV-specific CD8 + T cell proliferative and cytolytic capacity resulted in a rapid reduction of rebound viremia coincident with in vivo HIV-specific CD8 + T cell expansion and secondary cytotoxic effector cell differentiation. Collectively, these results highlight a potential role for recall cytotoxicity in limiting HIV-1 persistence during ART and attenuating rebound viremia after treatment interruption, which may inform strategies to elicit durable post-ART immune control.
One Sentence Summary: CD8 + T cell recall cytotoxicity against autologous HIV-1 epitopes associates with smaller and less transcriptionally active proviral reservoirs during prolonged antiretroviral therapy initiated during chronic infection.

DOI: https://doi.org/10.1101/2025.10.10.25337688
iScience. 2025 Nov 21. 28(11): 113893

LCMV-mediated loss of virtual memory CD8 T cells yields a functionally enhanced T cell subset.

Tabinda Hussain, Angela Nguyen, Daniel Thiele, Dulakara Kannangara, Zijian Huang, Ee Shan Pang, Alana Kirn, Sammy Bedoui, Kim L Good-Jacobson, Meredith O'Keeffe, Kylie M Quinn, Nicole L La Gruta.

  The unique cytokine responsiveness of virtual memory T (TVM) cells endows them with a potent capacity for bystander activation and effector function. Here, we investigated the antigen-independent impact of microbial infections on TVM cells. While Salmonella typhimurium or influenza A virus had no discernible effect, infection with lymphocytic choriomeningitis virus (LCMV) resulted in a rapid and profound depletion of TVM and true naive (TN) cells. Unlike TN cells, residual TVM cells exhibited a less differentiated phenotype and heightened T cell receptor (TCR) responsiveness, compared to cells from uninfected mice. Notably, these changes persisted into advanced age, with sustained reductions in TVM cell numbers and enhanced TCR sensitivity observed up to 18 months post infection, coincident with an attenuation of the senescent TVM cell phenotype. These findings reveal a previously unrecognized mechanism by which early-life pathogen exposure imprints long term changes on TVM cells, with broad implications for immune aging and lifelong immune competence.

Keywords:  components of the immune system; immunology

DOI:  https://doi.org/10.1016/j.isci.2025.113893
bioRxiv. 2025 Oct 10. pii: 2025.10.09.681414. [Epub ahead of print]

Scalable transcription factor mapping uncovers the regulatory dynamics of natural and synthetic transcription factors in human T cell states.

Riley D Z Mullins, Jesse Zaretsky, Emily Stoller, Michael Moore, Oliver Takacsi-Nagy, Oleg Shpynov, Remi Sampaleanu, Theodore L Roth, Ansuman T Satpathy, Robi D Mitra, Sidharth V Puram.

Heterogeneous T cell states are critical in immune responses and have been explored by CRISPR-based and synthetic domain-swapped transcription factor (TF) screens, yielding novel insights and immunotherapeutics. However, a scalable strategy to map TFs in primary human T cells is lacking, which limits our understanding of the functions of critical TFs. We therefore adapted a transposon-based TF mapping strategy termed Calling Cards for primary human CD8 T cells, applying it to five key TFs with undefined binding sites in this cell type: TOX, TOX2, TCF7, SOX4, and RBPJ. To derive biological insights from these data, we developed an analytical framework to integrate TF binding with multi-omic sequencing data, revealing convergence of TOX and TCF7 binding at dynamic enhancers of memory CD8 T cells. We then identified TF co-bound gene programs related to memory and exhaustion states in addition to putative gene targets of known and unappreciated TF roles, including TOX binding at critical genes of both exhaustion and terminal effector memory differentiation. To further scale our TF analysis platform, we modified Calling Cards to create TFlex : a method uniquely suited for multiplexed mapping of paralogous TFs. We applied TFlex to simultaneously map eight natural and domain-swapped TFs in primary human CD8 T cells, which demonstrated that domain-swapped TFs display emergent behavior in binding site selection and transcriptional effects on target genes that cannot be estimated as the sum of their constituent domains. Collectively, our data highlight the importance of scalable TF mapping in primary human T cells to elucidate TF function and the transcriptional regulation of cell states.

DOI: https://doi.org/10.1101/2025.10.09.681414
bioRxiv. 2025 Oct 26. pii: 2025.10.24.684274. [Epub ahead of print]

Divergent role of CD8 T cells with distinct metabolic phenotypes during curative radio-immunotherapy in hot versus cold tumors.

Alexa R Heaton, Nathaniel J Burkard, Anqi Gao, Anna Hoefges, Arika S Feils, Samantha K Burkard, Mildred A Felder, Noah W Tsarovsky, Dan V Spiegelman, Garrett M Lublin, Alina A Hampton, Aurora D'Amato, Huy Q Dinh, Alexander L Rakhmilevich, Amy K Erbe, Paul M Sondel, Melissa C Skala.

Immunotherapy has potential for impactful cancer cures by empowering patients' own immune cells. We developed a radio-immunotherapy regimen that can cure large immunologically hot and cold murine tumors. Here we explored the divergent role of CD8 T cells during this radio-immunotherapy in contrasting hot colon carcinoma versus cold melanoma models. We introduced an immunocompetent mouse model with mCherry expressing CD8 T cells to provide immune cell tracking in vivo . We investigated single-cell function, metabolism, and gene expression changes with temporal context using flow cytometry, in vivo multiphoton imaging, single-cell RNA sequencing, and multiplexed immunofluorescence to determine the underlying mechanisms. We found that in contrast to the hot colon carcinoma model, CD8 T cells from the cold melanoma model do not drive tumor cures, despite getting activated, possibly due to a static oxidative metabolism and exhausted phenotype as well as down regulation of tumor MHC-I expression. These findings have implications for improving immunotherapy response in immunologically cold cancers.

DOI: https://doi.org/10.1101/2025.10.24.684274
Cancer Drug Resist. 2025 ;8 55

Targeting tumor-draining lymph node to overcome resistance to cancer immunotherapy: an update.

Jianan Lu, Jiangnan Yu, Tuo Xu, Yina Li, Shuxian Chen, Qian Zhou, Lei Wang.

  Immune checkpoint inhibitor (ICI) resistance often stems from intratumoral T cell dysfunction. This review focuses on both tumor-intrinsic and tumor-draining lymph node (TDLN)-centric resistance mechanisms. We detail how specific defects within TDLNs - such as impaired dendritic cell migration and the establishment of immunosuppressive niches - initiate and perpetuate systemic immune dysfunction, ultimately leading to ICI resistance. To counter these challenges, we summarize the following TDLN-targeted strategies: (1) remodeling the TDLN immunosuppressive microenvironment to restore effective antigen presentation; (2) expanding the pool of progenitor exhausted T (Tpex) cells, with a focus on their primary reservoir in TDLNs; and (3) developing adoptive cell therapies using TDLN-derived Tpex cells to generate a robust, personalized antitumor response. By repositioning TDLNs as a central therapeutic target, recent findings suggest strategies aiming to overcome resistance at its source and improve ICI clinical outcomes.

Keywords:  Immune checkpoint inhibitor; immunotherapy resistance; tumor microenvironment; tumor-draining lymph node

DOI:  https://doi.org/10.20517/cdr.2025.126