bims-imicid Biomed News
on Immunometabolism of infection, cancer and immune-mediated disease
Issue of 2026–03–29
37 papers selected by
Dylan Gerard Ryan, Trinity College Dublin



  1. Front Cell Infect Microbiol. 2026 ;16 1795935
      Mitochondria are central hubs integrating cellular bioenergetics, redox balance, innate immune signaling, and metabolic homeostasis. During bacterial infections, these organelles are recurrent targets of pathogen-derived toxins, secreted effectors, and host inflammatory mediators, leading to a state broadly defined as mitochondrial stress. This stress encompasses alterations in oxidative phosphorylation, mitochondrial dynamics, calcium handling, reactive oxygen species (ROS) production, and activation or disruption of mitochondrial quality control pathways such as mitophagy. In this perspective, we propose mitochondrial stress as a conceptual framework linking bacterial infection and post-infectious metabolic disease. Using enteric bacterial pathogens such as Salmonella enterica serovars Typhimurium and Typhi, together with Vibrio parahaemolyticus, as conceptual models, we synthesize current evidence showing how distinct bacterial strategies converge on mitochondrial dysfunction and immunometabolic reprogramming of host cells. We argue that, while mitochondrial stress responses may initially support antimicrobial defense, their incomplete resolution may contribute to long-lasting metabolic and inflammatory alterations in epithelial, immune, and metabolic tissues. Persistent mitochondrial dysfunction may contribute to insulin resistance, chronic inflammation, and increased susceptibility to metabolic disease after infection. By framing mitochondrial stress as a central integrator of infection and metabolism, this perspective highlights key knowledge gaps and identifies mitochondria-centered pathways as potential targets to prevent or mitigate post-infectious metabolic sequelae.
    Keywords:  Salmonella enterica; Vibrio parahaemolyticus; bacterial infection; immunometabolism; mitochondrial stress; post-infectious metabolic disease
    DOI:  https://doi.org/10.3389/fcimb.2026.1795935
  2. Front Immunol. 2026 ;17 1738765
      Sepsis is a life-threatening organ failure syndrome triggered by dysregulated host responses to infection. During disease progression, macrophages drive initial hyperinflammatory responses and critically regulate the subsequent immunosuppressive phase. Emerging evidence reveals that macrophage phenotypes dynamically adapt through metabolic reprogramming, creating phenotype-metabolism interdependence. Notably, lactate-long considered merely a glycolytic byproduct-now emerges as a key regulator through histone lactylation. This epigenetic modification fine-tunes macrophage functionality and corrects inflammatory imbalance in sepsis. This breakthrough illuminates lactylation's central role in macrophage regulation, opening new diagnostic and therapeutic avenues. This review comprehensively examines lactylation mechanisms and their impact on metabolic control in sepsis-associated macrophages.
    Keywords:  glycolysis; lactation modification; macrophages; metabolic reprogramming; sepsis
    DOI:  https://doi.org/10.3389/fimmu.2026.1738765
  3. Int Immunopharmacol. 2026 Mar 23. pii: S1567-5769(26)00392-9. [Epub ahead of print]177 116547
      Tumor progression is critically shaped by the dynamic interplay between tumor cells and the tumor microenvironment (TME). The TME harbors a diverse array of immune cells, encompassing T cell, B cell, NK cell and macrophages. Among these, TAMs profoundly shape tumor growth and metastasis by interacting with tumor cells and other immune cells. To adapt to the varied immune and metabolic cues in the TME, they undergo dynamic metabolic reprogramming, which recent advances have shown to involve extensive remodeling of glucose, lipid, and amino acid metabolism, along with the tricarboxylic acid cycle. However, critical knowledge gaps remain regarding the cellular heterogeneity of TAM metabolic reprogramming, divergent metabolic signatures across TAM subsets, and context-dependent variations in metabolic rewiring among different cancer types. However, the mechanisms by which these metabolic alterations translate into distinct functional phenotypes and shape the immune landscape of the TME remain poorly defined. This review systematically synthesizes the current knowledge on how metabolic remodeling in TAMs regulates their polarization and pro-tumor functions. We specifically focus on delineating the heterogeneity of TAM metabolic features across tumor types and subsets and discuss the implications of these metabolic variations for TAM-mediated immunosuppression. Furthermore, we summarize the representative therapeutic agents targeting key metabolic nodes in TAMs. By integrating emerging insights into TAM metabolism and associated pharmacologic interventions, this review aims to identify key unanswered questions and provide a theoretical framework for developing precision immunotherapies that target TAM metabolic nodes without compromising anti-tumor immunity.
    Keywords:  Amino acid metabolism; Glucose metabolism; Lipid metabolism; Metabolic reprogramming; Tricarboxylic acid cycle; Tumor-associated macrophages
    DOI:  https://doi.org/10.1016/j.intimp.2026.116547
  4. Front Immunol. 2026 ;17 1779575
      Sepsis-related myocardial injury (SRMI) is a major cause of death in critically ill patients, with pathogenesis extending beyond inflammation to encompass dysregulated immunometabolic crosstalk. This review elucidates macrophage metabolic reprogramming as a central mechanism driving SRMI, detailing how a shift to aerobic glycolysis fuels pro-inflammatory responses, while oxidative phosphorylation supports reparative functions. We emphasize that metabolites like succinate, itaconate, and lactate act as potent signaling molecules, orchestrating epigenetic changes and inflammatory pathways. Furthermore, we deconstruct the critical immunometabolic dialogue mediated by extracellular vesicles (EVs) and signaling cascades among macrophages, cardiomyocytes, and endothelial cells. Translating these insights, we evaluate next-generation therapeutic strategies aimed at this immunometabolic axis, including precision small-molecule modulators, nucleic acid-based technologies, and biologics. These approaches represent a promising strategic shift from non-specific immunosuppression toward targeted immunometabolic modulation. This synthesis provides a foundational framework for understanding SRMI and charts a roadmap for developing novel precision medicine interventions to improve patient outcomes.
    Keywords:  exosomes; immunometabolism; macrophage polarization; metabolic reprogramming; mitochondria; sepsis-related myocardial injury
    DOI:  https://doi.org/10.3389/fimmu.2026.1779575
  5. Mucosal Immunol. 2026 Mar 21. pii: S1933-0219(26)00034-6. [Epub ahead of print]
      Macrophages play important roles in lung homeostasis and disease by interacting with their surrounding tissue microenvironment. Accordingly, macrophage metabolism and local metabolites shape immune responses in the lung. Here, I review the metabolic regulation of lung macrophages and regulation of lung immunity by macrophage metabolism in the context of lung injury, host defense, and tissue repair. First, the intrinsic regulation of macrophages by intracellular metabolism is discussed with a focus on how macrophages adapt to the metabolic milieu of the lung in steady state and when lung homeostasis is disturbed. Second, the extrinsic regulation of macrophages and lung immunity by extracellular metabolites is reviewed. Specifically, I present how metabolites acting on lung macrophages control their function. In addition, I discuss how metabolites produced by macrophages impact lung function. Finally, I provide an overview of future areas of research related to the regulation of lung macrophages by tissue-derived metabolites.
    Keywords:  Adaptation; Inflammation; Lung; Macrophages; Metabolism
    DOI:  https://doi.org/10.1016/j.mucimm.2026.03.010
  6. Front Immunol. 2026 ;17 1772536
      The immunometabolic checkpoint axis formed by the IDO1/AhR pathway and the HIF-1α pathway, which functionally antagonize each other via their competition for the shared transcriptional partner aryl hydrocarbon receptor nuclear translocator (ARNT), profoundly regulates the pathogenesis and progression of autoimmune diseases. Following activation of the aryl hydrocarbon receptor (AhR) by kynurenine (Kyn), a tryptophan metabolite generated by IDO1, the activated AhR and hypoxia-induced HIF-1α intensely compete for the limited pool of ARNT protein. This competition results in the formation of two distinct transcriptional complexes: AhR/ARNT and HIF-1α/ARNT. These complexes drive opposing immune programs. The AhR/ARNT complex promotes immune tolerance by facilitating Treg cell differentiation, inducing a tolerogenic phenotype in dendritic cells, promoting M2 macrophage polarization, and sustaining the survival of long-lived plasma cells. Conversely, the HIF-1α/ARNT complex enhances glycolysis and amplifies inflammation, driving Th17 cell differentiation, activating the pro-inflammatory functions of dendritic cells, promoting M1 macrophage polarization, and stimulating plasmablast proliferation. In autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), multiple sclerosis (MS), and membranous nephropathy (MN), dysregulation of this axis is characterized by excessive HIF-1α signaling and relative insufficiency of the IDO1/AhR pathway. This imbalance leads to the monopolization of ARNT by the HIF-1α pathways, consequently exacerbating Treg/Th17 imbalance, autoantibody production, and tissue damage. Targeting this axis, for instance through combined HIF-1α inhibitors and IDO1/AhR pathway agonists, holds promise as a novel metabolic intervention strategy for autoimmune diseases.
    Keywords:  ARNT; IDO1/AhR-HIF-1α axis; autoimmune diseases; immunometabolism; metabolic reprogramming
    DOI:  https://doi.org/10.3389/fimmu.2026.1772536
  7. bioRxiv. 2026 Mar 07. pii: 2026.03.06.710186. [Epub ahead of print]
      Obesity is a major risk factor for severe influenza A virus (IAV) infection, however, the innate immune mechanisms underlying this increased vulnerability remain unclear. Here, we identify significant defects in natural killer (NK) cell antiviral responses in mice with diet-induced obesity. In lean mice, NK cells are critical for protection as NK cell depletion during IAV infection led to increased lung viral load, morbidity, and mortality. In contrast, in obese mice NK cell depletion had minimal impact on viral replication or survival. Notably, IAV infection in obese mice recapitulated the phenotype observed in NK cell-depleted lean mice, indicating that obesity is associated with preexisting NK cell dysfunction. Following IAV infection, obese NK cells in the lung were functionally impaired with diminished activation (CD69 + ), cytokine production (IFN-γ), and cytolytic activity (Granzyme B) accompanied by defects in the mTOR signaling pathway and reduced glycolytic and oxidative metabolism. Bulk and spatial lipidomics revealed obesity and infection-driven remodeling of the lung lipidome. We observed increased triglyceride accumulation, abundance of long-chain free fatty acids, and a shift toward monounsaturated phospholipid species, reshaping the lung microenvironment that coincides with NK cell metabolic dysfunction. Consistent with this lipid-rich environment, obese NK cells sustained high expression of the lipid transporter CD36 post-IAV infection and accumulation of intracellular lipids (LipidTOX + ), consistent with mechanisms known to suppress NK cell function. Notably, short-term weight loss (4 weeks) was sufficient to restore NK cell metabolism, antiviral function, and survival following IAV infection. These findings uncover a lipid-associated mechanism regulating NK cell function and show it plays a critical role in defense against infection and that it is dysfunctional in obesity. We suggest that targeting immunometabolism could lead to new antiviral therapies and potentially improve vaccine efficacy, especially in high-risk populations such as obesity.
    GRAPHICAL ABSTRACT:
    DOI:  https://doi.org/10.64898/2026.03.06.710186
  8. Cell Metab. 2026 Mar 23. pii: S1550-4131(26)00085-9. [Epub ahead of print]
      Amino acid (AA) uptake is essential for T cell metabolism and function, but how tissue sites and inflammation affect CD4+ T cell subset requirements for specific AAs remains uncertain. Here, we tested CD4+ T cell AA demands with in vitro and in vivo CRISPR screens and identified subset- and tissue-specific dependencies on the AA transporter SLC38A1 (SNAT1). While dispensable for T cell persistence and expansion in vivo in lung inflammation, SLC38A1 was critical for Th1, but not Th17, cell-driven experimental autoimmune encephalomyelitis (EAE) and contributed to Th1 cell-driven inflammatory bowel disease. SLC38A1 deficiency reduced mTORC1 signaling and glycolytic activity in Th1 cells, in part by reducing glutamine uptake and disrupting hexosamine biosynthesis and redox regulation. Pharmacological inhibition of SLC38 transporters also delayed Th1-mediated EAE but did not affect lung inflammation. CD4+ T cells thus have subset- and tissue-specific nutrient transporter dependencies that may guide new metabolic approaches for selective immunotherapies.
    Keywords:  Slc38a1; T cell; amino acid transport; glutaminolysis
    DOI:  https://doi.org/10.1016/j.cmet.2026.02.016
  9. Cell Signal. 2026 Mar 23. pii: S0898-6568(26)00148-8. [Epub ahead of print]143 112496
      Metabolic reprogramming within the tumor microenvironment is a critical driver of CD8+ T cell dysfunction that limits the efficacy of cancer immunotherapy. While glucose and amino acid deprivation are well-characterized, lipid metabolic rewiring has emerged as a fundamental determinant of T cell fate. This review systematically examines the mechanisms by which the tumor microenvironment disrupts CD8+ T cell lipid metabolism to promote functional exhaustion and ferroptosis. We first discuss how local stressors such as hypoxia and acidosis alongside systemic host factors including obesity and hyperlipidemia synergistically impose a metabolic siege on infiltrating T cells. We then detail the molecular pathways of dysregulation revealed by recent lipidomic profiling, including CD36-mediated uptake of oxidized lipids that drives ferroptosis, as well as the dysregulation of cholesterol homeostasis that impairs TCR signaling and induces endoplasmic reticulum stress via the IRE1α-XBP1 axis, which directly drives the transcriptional expression of immune checkpoints. Finally, we evaluate therapeutic strategies such as pharmacological modulation of lipid transporters and metabolic engineering of CAR-T cells which hold promise for restoring metabolic fitness and reinvigorating antitumor immunity.
    Keywords:  CD8(+) T cells; Ferroptosis; Immunotherapy; Lipid metabolism; T cell exhaustion; Tumor microenvironment
    DOI:  https://doi.org/10.1016/j.cellsig.2026.112496
  10. Liver Int. 2026 Apr;46(4): e70613
       BACKGROUND AND AIMS: Metabolic associated steatohepatitis (MASH) is a critical stage of MAFLD, lacking effective therapies. Gut microbiota and their metabolites, particularly short-chain fatty acids (SCFAs), are increasingly recognised as modulators of hepatic metabolism and immune responses. We investigated whether Prevotella could ameliorate MASH by regulating CD8+ T-cell metabolism.
    METHODS: Faecal samples from MASH patients and healthy controls were analysed by 16S rDNA sequencing and untargeted metabolomics. MASH mouse models, germ-free mice and ex vivo CD8+ T-cell cultures were used to assess the effects of Prevotella and butyrate on glycolysis, PI3K/AKT/mTOR signalling and liver pathology. Metabolic activity was measured using ECAR, 2-NBDG uptake and lactate production; molecular changes were evaluated by qPCR, western blotting and flow cytometry.
    RESULTS: 16S rDNA sequencing revealed a significant reduction of Prevotella abundance in MASH patients compared with healthy controls, which was inversely correlated with hepatic steatosis and CD8+ T-cell infiltration. In MCD diet-induced MASH mice, oral administration of Prevotella alleviated hepatic lipid accumulation and collagen deposition. In germ-free mice, colonisation with Prevotella similarly improved liver histology. Mechanistically, Prevotella suppressed glycolytic activity in CD8+ T cells, as shown by decreased 2-NBDG uptake, ECAR measurements and reduced expression of glycolytic enzymes (HK2, PKM2, LDHA). Additionally, Prevotella downregulated the PI3K/AKT/mTOR signalling pathway in CD8+ T cells, linking its metabolic effects to immune modulation. Notably, the combination of Prevotella with a glycolysis inhibitor did not further enhance its therapeutic efficacy compared with Prevotella alone, indicating that suppression of glycolysis is a major mechanism underlying Prevotella's protective effects.
    CONCLUSION: Prevotella mitigates MASH by downregulating the PI3K/AKT/mTOR-glycolysis axis in CD8+ T cells via butyrate-dependent mechanisms, highlighting its potential as a microbial therapeutic candidate for MASH.
    Keywords:  CD8+ T cells; MASH; PI3K/AKT/mTOR signalling; Prevotella; glycolysis
    DOI:  https://doi.org/10.1111/liv.70613
  11. Viruses. 2026 Mar 06. pii: 326. [Epub ahead of print]18(3):
      Vesicular stomatitis virus (VSV) is a promising oncolytic virus whose replication efficiency and tumor selectivity are strongly influenced by host cell metabolism. Cancer cells, including glioblastoma, exhibit profound rewiring of central carbon metabolism to sustain proliferation, redox balance, and biosynthetic demand, yet how these metabolic states regulate VSV replication remains incompletely defined. Here, we investigated the dependency of VSV replication on glycolysis, the pentose phosphate pathway (PPP), and glutamine metabolism in A172 human glioblastoma cells. Pharmacologic inhibition of glycolysis using 2-DG strongly suppressed VSV replication in a dose-dependent manner, highlighting a robust requirement for glycolytic flux and downstream intermediates. While inhibiting the PPP with 6-AN, a nicotinamide adenine dinucleotide (NAD) analog, markedly impaired viral replication, D-ribose was unable to rescue the inhibition, indicating that nucleotide precursor limitation alone was insufficient to explain this effect. Interestingly, depletion of glucose 6-phosphate dehydrogenase (G6PD), a key enzyme in the PPP, resulted in significant enhancement of VSV replication. Restoration of viral replication by NAD+ precursors in the presence of 6-AN or suppression of replication by the NAMPT inhibitor FK866 suggested NAD+ availability as a critical determinant of VSV replication. Additionally, blockade of glutaminase activity with BPTES reduced viral replication, underscoring the importance of anaplerotic pathways in glioblastoma cells. Collectively, these findings demonstrate that VSV replication is tightly coupled to metabolic programs, particularly those governing energy production and NAD(P)H balance. This work provides a metabolic framework for optimizing oncolytic VSV therapies and suggests that metabolic interventions in cancer treatment may influence oncolytic virus efficacy.
    Keywords:  2-DG; NAD+ metabolism; glutaminolysis; glycolysis; pentose phosphate pathway; siRNA-mediated depletion; vesicular stomatitis virus
    DOI:  https://doi.org/10.3390/v18030326
  12. Viruses. 2026 Feb 27. pii: 284. [Epub ahead of print]18(3):
      Porcine reproductive and respiratory syndrome virus (PRRSV) infection relies on glycolytic reprogramming to support replication, but the mechanisms driving this metabolic shift remain poorly understood. The stimulator of interferon genes (STING), an innate immune adaptor, recently emerged as a metabolic regulator by directly binding and inhibiting hexokinase-2 (HK2), a key rate-limiting enzyme in glycolysis. Whether PRRSV exploits the STING-HK2 axis to unleash glycolysis for its own replication is unknown. Here we demonstrate that PRRSV infection induced STING degradation and promoted HK2 suppression, activating glycolysis for viral replication. In PRRSV-infected Marc-145 cells, lactate production (a glycolysis marker) and HK2 expression increased time-dependently, peaking at 48 h post-infection (hpi). Conversely, STING protein levels decreased significantly at 36 hpi and further at 48 hpi, suggesting a correlation between STING downregulation and glycolytic activation. The HK2 inhibitor 2-deoxy-D-glucose reduced lactate production and viral load, while the glycolysis activator PS48 enhanced both. STING knockdown via siRNA increased HK2 expression, lactate secretion, and PRRSV nucleocapsid protein levels, whereas STING overexpression suppressed these phenotypes. Co-immunoprecipitation and confocal microscopy demonstrated direct STING-HK2 interaction and cytoplasmic co-localization, maintained during PRRSV infection. HK2 overexpression promoted viral replication without altering STING levels, confirming HK2 as a downstream effector. In conclusion, PRRSV-triggered degradation of STING enhances HK2 expression, promoting lactate accumulation and accelerating viral replication. These findings suggest that the STING-HK2 axis can act as a critical viral metabolic checkpoint and highlight targeting metabolic-immune crosstalk as a potential anti-viral strategy.
    Keywords:  HK2; PRRSV; STING; glycolysis; viral replication
    DOI:  https://doi.org/10.3390/v18030284
  13. PeerJ. 2026 ;14 e20971
      Glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway (PPP), plays a pivotal role in immune regulation by regulating metabolic reprogramming and redox homeostasis of immune cells. It mediates the production of nicotinamide adenine dinucleotide phosphate (NADPH) and ribose-5-phosphate (R5P), which are essential for the activation, proliferation, and effector function of T lymphocytes, B lymphocytes, macrophages, and neutrophils-specifically promoting T/B cell-mediated adaptive immunity and macrophage/neutrophil-mediated innate immune responses. Abnormal G6PD activity (deficiency or overexpression) is closely associated with the pathogenesis of immune-related diseases: G6PD deficiency increases susceptibility to autoimmune diseases (e.g., rheumatoid arthritis, systemic lupus erythematosus) and infectious diseases (e.g., hepatitis, malaria, COVID-19) by inducing oxidative stress and immune cell dysfunction; in tumor immunity, G6PD dualistically promotes tumor cell proliferation while regulating anti-tumor immunity via modulating cytoxic D8+ T cell exhaustion and macrophage polarization. Additionally, G6PD-targeted immunotherapies, including small-molecule inhibitors and gene therapy, have shown promising preclinical potential for treating immune-related diseases. These findings highlight G6PD as a key metabolic-immune hub, providing critical theoretical basis for understanding immune regulation mechanisms and developing novel diagnostic and therapeutic strategies for autoimmune diseases, infectious diseases, and tumors.
    Keywords:  Glucose-6-phosphate dehydrogenase; Immune cells; Immune regulation; Immune-related diseases; Therapeutic target
    DOI:  https://doi.org/10.7717/peerj.20971
  14. Front Immunol. 2026 ;17 1691946
      Synovitis and gradual joint degeneration are hallmarks of rheumatoid arthritis (RA), a chronic inflammatory illness. To sustain inflammation and tissue damage, pathogenic immune and stromal cells undergo specific metabolic reprogramming that alters glycolysis, oxidative phosphorylation, and lipid metabolism. This pathology is driven by immunometabolic dysregulation, according to new research. This review summarizes the current understanding of cell-type-specific immunometabolic dysregulation in RA, with particular attention to T cells, macrophages, B cells, and fibroblast-like synoviocytes. We assess how high-dimensional biomarkers, such as blood-based metabolomic, transcriptomic, and proteomic signatures, and synovial molecular pathotypes can be used to stratify patients and predict how well biologic and targeted treatments will work. We also reviewed treatment approaches targeting immunometabolic pathways, including new metabolic inhibitors and drug repurposing, such as metformin. To facilitate a more individualized and efficient RA treatment, we conclude by offering a clinically applicable paradigm to integrate immunometabolic profiling into precision medicine.
    Keywords:  clinical applications; immunometabolism; personalized medicine; rheumatoid arthritis; rheumatoid arthritis (RA)
    DOI:  https://doi.org/10.3389/fimmu.2026.1691946
  15. Front Immunol. 2026 ;17 1786324
       Introduction: Pregnancy requires coordinated immunometabolic adaptations that allow maternal immune tolerance while preserving tissue remodeling and host defense. Circulating monocytes contribute critically to these processes, yet how gestation shapes their metabolic state and functional specialization remains incompletely defined.
    Methods: We investigated the metabolic and functional phenotype of maternal monocytes during earlymid pregnancy (1620 weeks of gestation) and explored the contribution of trophoblast-derived signals using an in vitro macrophage model and trophoblast-conditioned media.
    Results: Maternal circulation was enriched in CD14+CD16+ monocytes, accompanied by increased plasma lactate levels and elevated ex vivo lactate secretion by purified monocytes, without changes in mitochondrial mass or membrane potential. Monocytes from pregnant women displayed enhanced long-chain fatty acid uptake and increased expression of the fatty acid transporter CD36, while lipid droplet accumulation remained unchanged. Pregnancy-associated efferocytosis was dependent on fatty acid oxidation (FAO), as pharmacological FAO inhibition abrogated this response. Transcriptional profiling revealed differential regulation of TAM receptors, characterized by increased MERTK and reduced AXL expression, consistent with a homeostatic efferocytic program. Trophoblast-derived conditioned media recapitulated key features of this phenotype in macrophages, inducing fatty acid uptake, lipid dropletmitochondria colocalization, and upregulation of CPT1, DGAT1, LXRa and RARa. In this model, FAO was required to sustain ATP production and M2-like marker expression, while monocarboxylate transport was necessary for efficient efferocytosis and fatty acid uptake.
    Discussion: Together, these findings identify a coordinated immunometabolic program in maternal monocytes integrating glycolysis, lactate signaling, and FAO, likely instructed by trophoblast-derived cues, to enhance efferocytic and pro-resolving functions during pregnancy. This metabolic adaptation may represent a systemic mechanism supporting immune tolerance and tissue remodeling in early gestation.
    Keywords:  fatty acid oxidation; immunometabolism; lactate; macrophage; maternal immune homoestasis; monocyte; pregnancy
    DOI:  https://doi.org/10.3389/fimmu.2026.1786324
  16. Front Pharmacol. 2026 ;17 1731683
      Psoriasis is a chronic inflammatory skin disorder driven by dysregulation of the Treg/Th17 axis, where enhanced Th17 activity promotes keratinocyte proliferation and inflammation, while impaired Treg function exacerbates immune dysregulation. Emerging evidence highlights peroxisome proliferator-activated receptor γ (PPARγ) as a key regulator of fatty acid oxidation (FAO), a metabolic pathway critical for Treg differentiation and function. PPARγ activation enhances FAO via upregulation of CD36, CPT1, and AMPK signaling, while suppressing glycolysis, thereby skewing the Treg/Th17 balance toward immune tolerance. Concurrently, short-chain fatty acids (SCFAs), microbial metabolites with immunomodulatory properties. ameliorate psoriatic inflammation by promoting Treg expansion, inhibiting Th17 polarization, and modulating innate immune cells (neutrophils, dendritic cells, and macrophages). SCFAs exert their effects through receptor-dependent signaling and epigenetic mechanisms (HDAC inhibition), while derivative compounds and probiotic interventions enhance therapeutic potential. This review summarizes mechanistic insights into PPARγ-driven FAO and SCFA-mediated immunomodulation, proposing novel metabolic and microbiome-targeted strategies for psoriasis treatment.
    Keywords:  Treg/Th17 axis; fatty acid oxidation; immunomodulation; peroxisome proliferator-activated receptor γ; psoriasis; short-chain fatty acids
    DOI:  https://doi.org/10.3389/fphar.2026.1731683
  17. J Virol. 2026 Mar 24. e0014726
      Viruses rely on energy and biosynthetic materials of host cell from glucose metabolism to support their replication, and glucose plays a crucial role in viral infection. In this study, we found that porcine epidemic diarrhea virus (PEDV) infection significantly increased cellular glucose uptake and stimulated the production of the glycometabolite lactate. Exogenous supplementation of glucose or L-lactate confirmed that it significantly promoted PEDV proliferation, indicating that replication of PEDV was enhanced by regulating host glucose metabolism, particularly reprogramming glycolysis. Based on these findings, we explored the potential antiviral approach targeting the virus through regulating glycolytic processes. Metformin hydrochloride (MH) is a well-known hypoglycemic agent, which has shown notable anti-PEDV activity. After MH treatment, the transcriptome analysis showed the differential genes were mainly enriched in PI3K-AKT signaling pathway, and the expression levels of its downstream molecule GSK3B and MYC were significantly upregulated and downregulated, respectively. The gene expression related to glycolysis was also significantly inhibited. Further experiments showed that MH significantly inhibited the phosphorylation of AKT and its translocation to plasma membrane, while reducing the phosphorylation level of GSK3B. MH maintained GSK3B in a non-phosphorylated state by blocking the activation of the EGFR/PI3K/AKT/GSK3B pathway, mediated the degradation of c-MYC through phosphorylation, inhibited the glycolysis process, reduced the production of lactic acid, and finally exerted its antiviral effect. This study demonstrated that PEDV infection could induce glycolysis through metabolic reprogramming, thereby promoting viral replication; whereas, MH was able to effectively reverse this process, significantly inhibiting the virus-induced glycolysis pathway and exhibiting antiviral activity.IMPORTANCEThis study aims to elucidate the antiviral effects and molecular mechanisms of MH against PEDV. The results show that MH can inhibit the activation of the PI3K-AKT signaling pathway induced by PEDV infection, thereby suppressing the production of the glycolytic product L-lactic acid and ultimately resisting PEDV infection. This research provides new insights into the prevention and control of PEDV and offers scientific evidence for the application of MH in veterinary medicine.
    Keywords:  MH; PEDV; PI3K-AKT pathway; glycolysis
    DOI:  https://doi.org/10.1128/jvi.00147-26
  18. Cell Death Dis. 2026 Mar 24.
      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 defence, yet little is known about how JAKis reprogramme their activation and effector programmes. Here, we investigated naive and memory CD8 T cells from healthy donors stimulated in vitro in the presence of clinically relevant JAK inhibitors targeting JAK1 (JAK1i), JAK1/2 (JAK1/2i), or JAK1/3 (JAK1/3i). Flow cytometry, SCENITH, transmission electron microscopy, and RNA-seq were used to evaluate metabolic and functional programmes. 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 signalling. CD8 T cells from rheumatoid arthritis patients under JAKi therapy were analysed ex vivo for translational validation. These cells showed similar metabolic and signalling alterations, underscoring their clinical relevance. Altogether, these findings identify JAKis as disruptors of metabolic and signalling 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/10.1038/s41419-026-08610-7
  19. bioRxiv. 2026 Mar 20. pii: 2026.03.18.712640. [Epub ahead of print]
      Identifying metabolites and metabolic reactions specific to a cellular state, such as inflammatory state in immune cells, is of great interest, as it can provide important biomarkers and point to compounds and reactions of specific biological functions. However, many cell state-specific metabolites remain in the unannotated part of metabolome. Here we identified a series of sulfur-containing metabolites that are actively produced in macrophages upon classical activation, but not in resting state or alternative activation state. Isotopic tracing, in vitro assays and genetic perturbations further revealed that they are formed from reactions between free cysteine and several important intermediates in glycolysis and TCA cycle. Upon classical activation, macrophages specifically upregulate the import of cystine via Slc7a11 , supporting the production of these adducts. Their production dynamically responds to changes in central metabolism, environmental nutrient levels, and is regulated by nitric oxide. Finally, we confirmed these newly identified compounds also present in human samples, and most of them are significantly elevated in inflammatory granuloma annulare lesions. This work elucidated a previously uncharted part of metabolic network that is associated with inflammation and metabolic stress condition, which has important implications and set foundation for many future discoveries.
    DOI:  https://doi.org/10.64898/2026.03.18.712640
  20. PLoS Genet. 2026 Mar 24. 22(3): e1012094
      The evolutionarily conserved mechanistic Target of Rapamycin (mTOR) pathway connects energy and nutrient availability to growth, proliferation, differentiation, immunity and survival. Here, we investigated the role of the mTOR pathway in Drosophila hematopoiesis and immunity using genetic and transcriptomic analyses of peripheral larval blood cells (hemocytes). We show that blood cell-directed mTor expression induced lamellocyte differentiation as seen after parasitoid wasp infection. Genetic epistasis revealed that lamellocyte hematopoiesis downstream of mTor is mediated by the JNK and p38 pathways. Transcriptomic profiling showed largely similar changes in gene expression patterns of wasp infected and mTor overexpressing hemocytes. While mTOR signaling is necessary for proper lamellocyte differentiation, mTOR Complex 1 (mTORC1) activity is suppressed in mature lamellocytes. Our transcriptome data indicated that hemocyte activation is accompanied by a shift in metabolism towards aerobic glycolysis for energy production, the oxidative pentose phosphate pathway for NADPH recycling, ROS production and detoxification as well as glutaminolysis for glutathione production. Our data highlight the key role of mTOR in controlling blood cell fate in Drosophila.
    DOI:  https://doi.org/10.1371/journal.pgen.1012094
  21. Cell Rep. 2026 Mar 20. pii: S2211-1247(26)00227-5. [Epub ahead of print]45(4): 117149
      Kynurenine, an intermediate metabolite of tryptophan metabolism, suppresses the antitumor activity of CD8+ T cells by activating the aryl hydrocarbon receptor (AHR). Its role in adaptive immunity is poorly understood. Outside the liver, kynurenine is mainly produced by indoleamine 2,3-dioxygenase 1 (IDO1) and further degraded by kynureninase (KYNU). This report shows that KYNU is predominantly expressed in human and mouse antigen-presenting cells (APCs) in vivo, GM-CSF-differentiated macrophages and dendritic cells in vitro, and alveolar macrophages collected in situ, and is functionally active in breaking down kynurenine into catabolic products without contributing toward de novo NAD+ synthesis. Importantly, while CD8+ T cells uptake kynurenine, they lack active KYNU, leading to AHR-dependent immunosuppression. However, KYNU-expressing APCs can deplete extracellular kynurenine, prevent AHR activation, and restore IFN-γ production in CD8+ T cells. This highlights the importance of KYNU-expressing APCs in combating kynurenine-induced immune suppression against tumors.
    Keywords:  CD8(+) T cells; CP: cancer; CP: metabolism; GM-CSF; IDO1; KYNU; alveolar macrophages; antigen-presenting cells; antitumor immunity; bone marrow; kynureninase; kynurenine pathway; macrophage metabolism; tryptophan catabolism
    DOI:  https://doi.org/10.1016/j.celrep.2026.117149
  22. Sci Immunol. 2026 Mar 27. 11(117): eaeb1459
      Lipid accumulation in the tumor microenvironment is a hallmark of solid tumors, with increased palmitate (PA) availability fostering tumor progression. Although PA's direct effects on cancer cells are well described, its impact on CD8 T cells [cytotoxic T lymphocytes (CTLs)] remains unclear. Here, we show that PA irreversibly impairs CTL mitochondrial metabolism, leading to the loss of effector functions and compromised antitumor immunity. PA-induced mitochondrial dysfunction reduced histone acetylation and chromatin accessibility, suppressing transcription of genes involved in T cell replication and effector programs. We identified sphingosine kinase 2 (SPHK2) as a key mediator of PA-induced dysfunction, with pharmacological inhibition of SPHK2 restoring mitochondrial fitness, rescuing CTL effector function, and promoting antitumor activity. These findings uncover a distinct mechanism by which PA drives immune evasion in tumors and highlight SPHK2 as a potential therapeutic target to enhance T cell-based immunotherapies.
    DOI:  https://doi.org/10.1126/sciimmunol.aeb1459
  23. Nat Commun. 2026 Mar 23.
      Tumors employ diverse mechanisms to impair conventional dendritic cell (cDC) function within the tumor microenvironment, yet the underlying processes remain unclear. Here, we demonstrate that pentose phosphate pathway (PPP) reduction in late-stage intratumoral cDCs compromises their function. Both pharmacological and genetic inhibition of the PPP attenuate cDC-mediated antitumor responses. Conversely, PPP augmentation restores late-stage intratumoral cDC antitumor capacity. PPP deficiency in cDCs enhances the immune checkpoint PD-L1 expression level, and combining cDC-specific PPP potentiation with immune checkpoint blockade synergistically enhances immunotherapy efficacy. Mechanistically, PPP activation fuels purine metabolism, thereby increasing ATP and GTP levels required for 2'3'-cGAMP synthesis, ultimately promoting cGAS-STING signaling and STING-dependent cDC antitumor responses. The PPP is associated with STING-dependent cDC activities in tumor tissues from female patients with breast cancer. Collectively, our findings establish PPP as an intrinsic metabolic checkpoint in STING-mediated cDC antitumor immunity, and suggest targeting PPP in cDCs as a promising cancer immunotherapy strategy.
    DOI:  https://doi.org/10.1038/s41467-026-70934-x
  24. bioRxiv. 2026 Mar 17. pii: 2026.03.16.712107. [Epub ahead of print]
      Many intracellular pathogens stimulate host cell stress by directly or indirectly causing an imbalance in host nutrients; depletion of amino acid pools in particular can act as a danger signal to infected cells. Using a restrictive host model of Salmonella enterica serovar Typhi (S. Typhi) infection, we identify early induction the integrated stress response (ISR) by viable bacteria, but not heat-killed bacteria. Genetic deletion of the amino acid sensing ISR kinase GCN2 (also known as EIF2AK4) prevented early ISR activation during S. Typhi infection, and murine macrophages lacking GCN2 show impaired bacterial clearance and decreased cytokine output. Supplementation of wildtype C57BL/6 murine macrophages with only the non-essential amino acid asparagine was sufficient to suppress S. Typhi-induced ISR activation and deletion of S. Typhi ansB, encoding an asparaginase, prevented ISR activation during infection. Pharmacological inhibition of mammalian target of rapamycin (mTOR), the other major amino acid sensing pathway in eukaryotic cells, prevented GCN2 activation and ISR induction in murine macrophages, indicating an upstream role for mTOR in signaling to GCN2. These findings suggest a role for the ISR in macrophage innate immune responses to S. Typhi infection and highlight a potential difference in nutrient-dependent signaling between the S. Typhi-susceptible human host and the restrictive murine host centered around asparagine, mTOR, and GCN2.
    DOI:  https://doi.org/10.64898/2026.03.16.712107
  25. Molecules. 2026 Mar 15. pii: 982. [Epub ahead of print]31(6):
      Psoriasis, a chronic inflammatory skin disease, is driven by immune dysregulation and keratinocyte hyperproliferation, with current biologics facing limitations. Emerging evidence points to mitochondrial dysfunction and a pathological shift to aerobic glycolysis as core disease drivers. Here, we report that MitoFu-O, a novel mitochondria-targeting TPP-thiazole derivative, effectively ameliorates psoriasiform inflammation in imiquimod-induced mice and cytokine-stimulated keratinocytes. Mechanistically, MitoFu-O acts by inhibiting pathological glycolysis, downregulating key glycolytic enzymes (HK1, GAPDH, LDHA), and subsequently suppressing the activation of pivotal pro-inflammatory signaling pathways (MAPK, NF-κB, and STAT3). Our findings establish targeted mitochondrial modulation as a potent therapeutic strategy, positioning MitoFu-O as a promising lead compound that acts upstream of cytokine signaling by normalizing the metabolic reprogramming fundamental to psoriatic pathogenesis.
    Keywords:  TPP-thiazole derivatives; glycolysis inhibition; immune-metabolic regulation; mitochondria; psoriasiform inflammation
    DOI:  https://doi.org/10.3390/molecules31060982
  26. Biochim Biophys Acta Mol Basis Dis. 2026 Mar 22. pii: S0925-4439(26)00093-1. [Epub ahead of print] 168230
      Microglial hyperactivation-induced neuroinflammation is a central driver of neurological dysfunction after traumatic brain injury (TBI). Metabolic reprogramming is essential for microglial activation, but the specific metabolic alterations following TBI and their causal relationship with activation remain poorly defined. This study investigated the role and underlying mechanisms of glutamate-ammonia ligase (GLUL) in regulating microglial activation after TBI. A murine TBI model was established using a controlled cortical impact device, and brain injury severity, neuroinflammation, and behavioral outcomes were compared between wild-type and microglia-specific GLUL knockout mice. The inflammatory cytokine expression and amino acid metabolic fluxes assessed in GLUL-deficient microglia during activation in vivo and in vitro. Results showed that post-TBI microglia downregulates the GLUL expression, redirecting glutamate metabolism toward the pro-inflammatory arginine-citrulline cycle. This metabolic shift exacerbated microglial hyperactivation and aggravated neurological dysfunction following TBI. Conversely, inhibition of arginine-citrulline cycle attenuated microglial activation and suppressed pro-inflammatory cytokine release. Collectively, these findings identify a novel pathological mechanism linking metabolic alterations to microglial activation after TBI and suggest a metabolism-targeted strategy for anti-inflammatory therapy.
    Keywords:  Arginine-citrulline cycle; Glutamate-ammonia ligase; Microglia; Traumatic brain injury
    DOI:  https://doi.org/10.1016/j.bbadis.2026.168230
  27. Sci Adv. 2026 Mar 27. 12(13): eaec5757
      The advent of highly refined wheat products has reduced fiber consumption, which is associated with increased risk for inflammatory bowel disease (IBD). We found that enriching diets with wheat fiber (WF) protected mice against colitis, especially relative to a low-fiber diet, as assessed by clinical, histopathologic, morphologic, and immunologic parameters. WF's protection against colitis was independent of short-chain fatty acids (SCFAs) yet associated with preservation of microbiota diversity, including maintenance of Bacteroides thetaiotaomicron (B. theta), which was necessary and sufficient for WF's colitis protection. B. theta's presence in gnotobiotic mice resulted in WF-induced fecal metabolites that reprogrammed macrophages toward an M2-like phenotype. Metabolic and phenotypic reprogramming of macrophages ex vivo via WF-induced metabolites, followed by their transplantation into mice, recapitulated WF's protection against colitis. Thus, microbiota-mediated metabolism of WF promotes macrophages that reduce proneness to intestinal inflammation, suggesting a mechanism by which WF consumption may curb development of IBD.
    DOI:  https://doi.org/10.1126/sciadv.aec5757
  28. Metabolites. 2026 Mar 10. pii: 185. [Epub ahead of print]16(3):
      Glioblastoma (GBM) is a universally fatal cancer for which the standard of care has remained largely unchanged for the last 20 years. Recent work has demonstrated that most therapeutic trials for GBM fail due to complex mechanisms of immunosuppression mediated by both the innate and adaptive immune systems. Various metabolic alterations in the tumor microenvironment help maintain this local and systemic immunosuppression, of which the axis of hypoxia-driven tryptophan degradation has garnered substantial attention over the last decade. This paper synthesizes a much-needed elucidation of the immunometabolic reshaping of glioma, myeloid, endothelial, and lymphoid cell lineages induced by hypoxia. The current paper critically evaluates the role of IDO1/TDO2-mediated breakdown of tryptophan and the consequent accumulation of kynurenine, a metabolite that triggers GCN2- and AHR-mediated CD8+ T-cell exhaustion and supports regulatory T-cell differentiation and expansion. Furthermore, we propose a synthesis of mechanistic evidence that establishes a role for the Trp-GCN2-ATF4-VEGFA axis in hypoxia-induced immunosuppression, supporting that pro-tumoral metabolic dysregulation is directly linked to angiogenesis. In GBM, hypoxia and tryptophan-kynurenine pathway dysregulation operate as an integrated metabolic circuit that drives widespread immunosuppression. These mechanisms can be captured by a metabolic signature shared across nearly every cell type in the GBM microenvironment. Drawing on recent spatial transcriptomic, metabolomic, and pharmacologic studies, we outline how this metabolic axis shapes disease biology and how it can be targeted to restore effective antitumor immunity.
    Keywords:  GCN2–AHR signaling; IDO1/TDO2; glioblastoma; hypoxia (HIF-1α/HIF-2α); immunometabolism; metabolic reprogramming; precision immunotherapy; spatial transcriptomics; tryptophan–kynurenine pathway; tumor microenvironment
    DOI:  https://doi.org/10.3390/metabo16030185
  29. Redox Biol. 2026 Mar 20. pii: S2213-2317(26)00131-X. [Epub ahead of print]92 104133
      The oxidative stress of macrophage plays pivotal roles of acute and chronic inflammation and chronic fibrotic phases, in which the metabolic mechanism needs to be further explored. In our research, multi-omics analyses of human and murine during Benign airway stenosis (BAS) biopsy identified ACOD1 as a hallmark of immunometabolic regulation during acute inflammation stage. ACOD1 knockout aggravated both acute and chronic inflammation, which increased the granulation tissue formation. The ACOD1-itaconate axis, along with its derivative, 4-octyl itaconate (4-OI), orchestrated acute and chronic inflammation, which attenuated the fibrosis of BAS. 4-OI upregulated FTH1 expression in macrophages by activating NRF2, which effectively suppressed oxidative stress and acute inflammation. Furthermore, 4-OI promoted the packaging of FTH1 into macrophage-derived exosomes, which were transferred to fibroblasts in a SCARA5-dependent manner, inducing fibroblast ferroptosis and alleviating chronic fibrosis. In sum, this study illustrates that the ACOD1-itaconate metabolic axis decreases oxidative stress and inflammation in macrophage, which attenuates fibrosis by inducing FTH1 transfer, offering a therapeutic target for fibrotic airway diseases.
    Keywords:  Benign airway stenosis; Fibrosis; Inflammation; Itaconate; Macrophage
    DOI:  https://doi.org/10.1016/j.redox.2026.104133
  30. Int Immunopharmacol. 2026 Mar 19. pii: S1567-5769(26)00362-0. [Epub ahead of print]177 116517
      Trichinella spiralis (T. spiralis) infection can upregulate indoleamine 2,3-dioxygenase (IDO) in the host. To assess the relationship between IDO in CD4+ T cells (Helper T cells, Th) infected with T. spiralis and the ability of T. spiralis to escape host immune system attack, we investigated the immunomodulatory effects of T. spiralis infection in mice, focusing on the mechanism by which IDO modulates CD4+ T-cell function. The findings of this study revealed that T. spiralis increased IDO levels in mice and upregulated the expression of interleukin 10 (IL-10), interferon-gamma (IFN-γ), and tumor necrosis factor (TNF), but decreased the CD4+/CD3+ T-cell ratio. This effect was suppressed after 1-methyltryptophan (1-MT) treatment, indicating that it is IDO-dependent. High expression of IDO led to the catabolism of tryptophan via the tryptophan-kynurenine pathway, resulting in the high expression of general control Nonderepressible 2 (GCN2) and the phosphorylation of eukaryotic translation initiation factor 2 subunit alpha (eIF2α). These changes increased the apoptosis rate of CD4+ T cells and reduced their proliferation ability, which was confirmed through in vitro experiments. Additionally, T. spiralis-induced high expression of IDO in mice upregulated Foxp3 expression in CD4+CD25+ Treg cells, which plays a negative role in immune regulation in mice. Experimental evidence has revealed that mouse CD4+ T cells undergo apoptosis via IDO following T. spiralis infection, and that weakened proliferation leads to an imbalance in mouse immune function, facilitating the smooth survival of T. spiralis and evasion of host immune attack. These findings provide new directions and insights for studying the immune escape mechanism of T. spiralis and for the prevention and treatment of T. spiralis infection.
    Keywords:  CD4(+) T cells; Immune evasion; Indoleamine 2,3-dioxygenase; Trichinella spiralis; Tryptophan
    DOI:  https://doi.org/10.1016/j.intimp.2026.116517
  31. J Thorac Cardiovasc Surg. 2026 Mar 19. pii: S0022-5223(26)00768-3. [Epub ahead of print]
       OBJECTIVE: Controlled hypothermic storage of donor organs at 10°C is an emergent clinical standard in lung transplantation due to its superior graft protective effects. Itaconate, a known regulator of cell immunometabolism, has been shown to be upregulated in donor lungs preserved at 10°C for extended periods of static storage versus on ice. We hypothesized that itaconate may be an active agent in donor graft protection against ischemia-reperfusion injury, rather than a byproduct of 10°C graft metabolism.
    METHODS: We conducted cell-based screening of multiple formulations and concentrations of itaconate and its derivatives and identified 0.25 mM dimethyl itaconate as the most promising candidate for lung preservation. Lungs from Yorkshire pigs (n = 4/group) were randomized to be flushed with low potassium dextran solution ± 0.25 mM dimethyl itaconate, stored at 4°C for 36 hours to limit endogenous itaconate production, then assessed using ex-vivo lung perfusion.
    RESULTS: Lungs preserved with dimethyl itaconate had better function, as indicated by lower airway pressures, higher lung compliances, improved perfusate oxygenation, and less edema formation than controls. Perfusate pro-inflammatory cytokines were significantly lower with dimethyl itaconate. Tissue IκBζ levels declined, and dimethyl itaconate prevented tissue oxidative stress after reperfusion. High resolution respirometry indicated no inhibition of succinate dehydrogenase with dimethyl itaconate at 0.25 mM at either hypothermic or normothermic conditions.
    CONCLUSIONS: Dimethyl itaconate safely modulated inflammation and improved lung physiologic performance upon reperfusion, supporting itaconate's protective role in donor-lung preservation.
    Keywords:  Ex vivo lung perfusion; Itaconate; Lung preservation; Lung transplantation; Mitochondria
    DOI:  https://doi.org/10.1016/j.jtcvs.2026.03.570
  32. Int J Mol Med. 2026 Jun;pii: 144. [Epub ahead of print]57(6):
      Itaconate (ITA) is a metabolite produced by immune cells such as macrophages during inflammation or infection. ITA exhibits potent immunomodulatory functions, antioxidant effects and antibacterial properties. The present study aimed to provide a systematic review of the synthesis and metabolic regulatory mechanisms of ITA and its key roles in intestinal diseases. ITA affects inflammatory bowel disease (IBD), colorectal cancer (CRC), intestinal infection and other gut disorders via the regulation of signalling pathways, including the nucleotide‑binding oligomerization domain‑like receptor protein 3 inflammasome, NF‑κB and Nrf2 pathways. ITA also modulates the composition of the gut microbiota and enhances intestinal barrier function. The present study also aimed to summarize the therapeutic potential of ITA derivatives, providing a theoretical basis for the development of novel treatment strategies for intestinal disease.
    Keywords:  immunometabolism; inflammatory bowel disease; intestinal disease; itaconate; macrophages; therapeutic potential
    DOI:  https://doi.org/10.3892/ijmm.2026.5815
  33. Cell Death Discov. 2026 Mar 27.
      Lactate is recognized as a crucial signalling molecule within the tumor microenvironment, where it shapes immune responses by modulating various cell populations, including T cells and macrophages. However, its effect on natural killer (NK) cells, key effectors of early antitumor immunity, remains poorly understood. This study investigates how intratumoral lactate accumulation affects NK cell function in breast cancer, a neoplasm characterized by elevated glycolytic flux. An in-silico analysis of 882 breast cancer patients revealed that high lactate metabolism is inversely correlated with NK cell activation genes and is associated with poor prognosis. To corroborate these findings, NK cells from healthy donors were cultured under lactate-rich or control conditions. Lactate exposure impaired NK cell proliferation, downregulated activation markers and cytotoxic molecules, disrupted mitochondrial bioenergetics, and induced lipid accumulation, as demonstrated by flow cytometry, metabolic profiling, and Raman spectroscopy. Functional assays using microfluidic devices and degranulation tests revealed that lactate-exposed NK cells exhibited reduced chemotaxis and diminished cytotoxicity against MCF-7 and MDA-MB-231 breast cancer spheroids, accompanied by decreased CXCL9 and CXCL10 production. Pharmacologic inhibition of lactate transport, via Syrosingopine or MSC-4381 and AZD3965 combination, restored NK cell cytotoxicity in tumor co-cultures, as shown by increased NK cell degranulation, caspase-3/7-mediated tumor apoptosis, and spheroid shrinkage. Finally, GPR81 deletion mirrored these effects, enhancing NK cell activity. These findings identify lactate as a driver of NK cell suppression and highlight lactate transport and receptor targeting as a strategy to enhance NK cell-based immunotherapies in breast cancer and other lactate-rich tumors.
    DOI:  https://doi.org/10.1038/s41420-026-03063-5
  34. Cell Rep Methods. 2026 Mar 26. pii: S2667-2375(26)00043-3. [Epub ahead of print] 101343
      Transition metals, such as iron, support vital metabolic and signaling functions in immune cells. Cellular iron concentrations are tightly controlled. In T cells, both iron deficiency and iron overload have been linked to immune dysfunction. Homeostatic iron concentrations in T cells, and changes that occur during T cell activation, remain poorly understood due to difficulty of accurately measuring iron content in single cells, especially in small cells. Here, we describe the use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to accurately quantify the total amount of endogenous iron in individual primary human T cells. Our technique allows for targeted selection of single cells and reproducible quantification of iron at femtogram level. Our findings reveal that iron levels in resting T cells were similar across human donors. In contrast, T cell activation leads to diverse patterns between individual cells and donors, indicating specialized needs during differentiation.
    Keywords:  CP: biotechnology; CP: immunology; ICP-MS; LA-ICP-MS; T cells; human donors; iron metabolism; iron quantification; metalloimmunology; single-cell analysis; single-cell metallomics
    DOI:  https://doi.org/10.1016/j.crmeth.2026.101343
  35. Blood. 2026 Mar 24. pii: blood.2025031552. [Epub ahead of print]
      Iron is an essential element for most cellular processes and recent evidence highlighted its role in regulating the function of hematopoietic stem cells (HSCs). Abnormal iron levels impact HSC quiescence and self-renewal, however, the mechanism by which iron overload (IO) influences HSC function is still unknown. Here, we show that intracellular IO impairs mitochondrial fitness and bioenergetics, inducing metabolic rewiring. In thalassemic mice, as a model of chronic IO, HSCs accumulate mitochondria with elevated reactive oxygen species (mtROS), low membrane potential and reduced oxidative phosphorylation (OXPHOS). Mitochondrial defects are confirmed in other two models of IO, sickle cell disease and iron-loaded wild-type mice, and in vivo iron reduction rescues HSC mitochondria. IO HSCs are highly proliferating and in presence of damaged mitochondria rely on glycolysis for energy production. Notably, restoration of mitochondrial function by targeting in vivo mtROS improved the quiescence and self-renewal of IO HSCs. Our results unravel the critical interplay between iron, ROS and mitochondrial activity in HSCs, revealing that IO shapes HSC metabolic programs.
    DOI:  https://doi.org/10.1182/blood.2025031552
  36. Cell Host Microbe. 2026 Mar 24. pii: S1931-3128(26)00088-0. [Epub ahead of print]
      Inflammatory bowel disease (IBD) is a chronic relapsing and remitting disorder in which loss of intrinsic enteric neurons (iENs) has been documented. However, the contribution of gut microbiota to the loss of iENs in IBD remains poorly defined. Here, we identify an IBD-enriched intestinal pathogen, Clostridium symbiosum (C. symbiosum), which exacerbates iEN loss and colitis. Mechanistically, C. symbiosum-derived succinate, emerging as a central mediator, drives macrophage glycolysis via the H3K79succ/HK2 axis, thereby sustaining IL-1β secretion, which, in turn, promotes neuronal-specific NLRP3 inflammasome activation and consequent neuronal loss. We further demonstrated that preventing iEN loss effectively improves outcomes in C. symbiosum-exacerbated colitis. Importantly, we identified phiCS-1, an endolysin from C. symbiosum-specific bacteriophages, which efficiently lyses C. symbiosum and markedly attenuates C. symbiosum-mediated iEN loss and colitis. Together, our study provides insights into the intricate interplay between gut microbiota and immune-neuron crosstalk, offering avenues for targeted therapeutic interventions in IBD.
    Keywords:  Clostridium symbiosum; Endolysin phiCS-1; H3K79succ-HK2 axis; iEN loss; inflammatory bowel disease
    DOI:  https://doi.org/10.1016/j.chom.2026.03.001
  37. bioRxiv. 2026 Mar 19. pii: 2026.03.11.711069. [Epub ahead of print]
      Pseudomonas aeruginosa is a major cause of persistent pneumonias that are not readily cleared by seemingly appropriate antimicrobial therapy. We identified a reservoir of P. aeruginosa variants lacking expression of the H3-T6SS in patients with chronic but not acute pneumonia. A PAO1 ΔH3-T6 mutant caused increased infection in the murine lung as compared to the wild-type strain. The ΔH3 mutants exhibited increased transcription of genes involved in phagocytic uptake and respiration under conditions found in the phagolysosome, namely low O 2 , low pH and abundant itaconate. We confirmed increased intraphagocytic residence of the ΔH3 mutants and colocalization with LAMP1 within the phagolysosome of both bone marrow derived macrophages in vitro and in alveolar macrophages harvested directly from infected lungs. Persistence within macrophages required itaconate which preserved the viability of infected macrophages and boosted bacterial bioenergetics to optimize consumption of available carbon sources. Our findings demonstrate that selection for loss of H3-T6SS loss of function mutations promotes the metabolic versatility that enables P. aeruginosa to cause intractable pulmonary infection.
    DOI:  https://doi.org/10.64898/2026.03.11.711069