Research Article
Abstract
Metabolic syndrome and excessive alcohol consumption (MetALD) result in liver injury and fibrosis, which are driven by increased collagen production by activated hepatic stellate cells (HSCs). Our previous studies demonstrated that LARP6, an RNA-binding protein, may facilitate collagen production. However, the expression and function of LARP6 as a regulator of fibrosis development in a disease-relevant model remain poorly understood. We demonstrated that LARP6 was upregulated in human activated HSCs in metabolic dysfunction–associated steatohepatitis (MASH) and MetALD. By using single-nucleus RNA-seq and assay for transposase-accessible chromatin sequencing, we showed that JUNB upregulated LARP6 expression in activated HSCs. Moreover, LARP6 knockdown in human HSCs suppressed fibrogenic gene expression. By integrating enhanced crosslinking and IP analysis and ribosome profiling in HSCs, we showed that LARP6 interacted with mature mRNAs comprising more than 300 genes, including RNA structural elements within COL1A1, COL1A2, and COL3A1 to regulate mRNA expression and translation. IP–mass spectrometry analysis demonstrated LARP6 protein–protein interactions with mRNA translation components and the actin cytoskeleton. Furthermore, Dicer substrate siRNA-based HSC-specific gene knockdown or pharmacological inhibition of LARP6 attenuated fibrosis development in human MASH and MetALD liver spheroids. Our results suggest LARP6 plays a key role in fibrogenic gene regulation and that targeting LARP6 in human HSCs may represent a therapeutic approach for liver fibrosis.
Authors
Hyun Young Kim, Orel Mizrahi, Wonseok Lee, Sara B. Rosenthal, Cuijuan Han, Brian A. Yee, Steven M. Blue, Jesiel Diaz, Jyotiprakash P. Jonnalagadda, Lena A. Street, Kanani Hokutan, Haeum Jang, Charlene Miciano, Chen-Ting Ma, Andrey A. Bobkov, Eduard Sergienko, Michael R. Jackson, Marko Jovanovic, Branko Stefanovic, Tatiana Kisseleva, Gene W. Yeo, David A. Brenner
Abstract
Neonatal life is marked by rapid antigen exposure, necessitating establishment of peripheral immune tolerance via conversion of naive CD4+ T cells into Tregs. We demonstrated heightened capacity for FOXP3 expression and tolerogenic function among cord blood versus adult blood naive CD4+ T cells. Further, this was linked to a distinct cord blood metabolic profile and elevated neonatal expression of the NADase, CD38. Early-life naive CD4+ T cells demonstrated a metabolic preference for glycolysis, which directly facilitated their differentiation trajectory. We revealed an age-dependent gradient in CD38 levels on naive CD4+ T cells and showed that high CD38 expression contributes to the glycolytic state and tolerogenic potential of neonatal CD4+ T cells, effects mediated at least partly via the NAD-dependent deacetylase SIRT1. Thus, the early-life window for peripheral tolerance in humans is critically enabled by the immunometabolic state of the naive CD4+ compartment.
Authors
Laura R. Dwyer, Andrea M. DeRogatis, Sean Clancy, Victoire Gouirand, Charles Chien, Elizabeth E. Rogers, Scott P. Oltman, Laura L. Jelliffe-Pawlowski, Theo van den Broek, Femke van Wijk, Susan V. Lynch, Rachel L. Rutishauser, Allon Wagner, Alexis J. Combes, Tiffany C. Scharschmidt
Abstract
Integrin-targeted therapies are under investigation for HIV-associated neuroinflammation, yet their effect on CNS antiviral immunity remains undefined. We examined the role of α4 integrin in T cell–mediated neuroimmune surveillance using SIV-infected macaques with α4 blockade and T cell–specific α4-deficient mice. In macaques, α4 blockade preserved CD4+ Th1 cell access to the brain parenchyma but impaired CD8 effector recruitment, disrupting antiviral control. Despite stable cerebrospinal fluid viral loads, hippocampal SIV RNA increased under blockade. Single-cell analyses revealed α4 enrichment in CD8 effector memory (Tem) cells; blockade reduced inferred CD8+ Tem-monocyte interactions and heightened innate immune activation in the hippocampus. Microscopy demonstrated persistent SIV-induced microglial simplification despite treatment. Th1 CD4 effectors correlated positively with gray matter viral RNA, whereas α4β7+ CD8+ T cells correlated inversely, implicating impaired CD8+ Tem recruitment in elevated parenchymal viral burden. In mice, α4 proved dispensable for CD4 trafficking to inflamed brain but essential for CD8 effector access across CNS compartments and for both subsets to reach skull marrow. These findings establish that α4 integrin governs CD8-mediated neuroimmune surveillance through coordinated cellular positioning, with blockade enabling viral seeding while disrupting spatially organized antiviral defense.
Authors
Pabitra B. Pal, Sonny R. Elizaldi, Giovanne B. Diniz, Ravi Prakash Rai, Yashavanth Shaan Lakshmanappa, Anil Verma, Daniel Rossmiller, Jesse Kaufman, Rahul Srivastava, Sean Ott, Carissa T. Erices, Kayla Schwartz, Danielle Beckman, Zhong-Min Ma, Alex Petkov, Daniel Newhouse, Dhivyaa Rajasundaram, John H. Morrison, Reben Raeman, Smita S. Iyer
Abstract
Metabolic–inflammatory crosstalk orchestrates muscle repair. Although pyroptosis typically aggravates sterile injury, we demonstrated that GSDME-dependent pyroptotic signaling associated with recruited myeloid cells paradoxically supported regeneration. GSDME expression was induced in postsurgical human muscle injury and murine damage models. Gsdme deficiency delayed functional recovery and exacerbated injury-induced myosteatosis, a pathological form of intramuscular ectopic fat deposition. Time-series and scRNA-seq analyses revealed that GSDME loss shifted the transcriptional program from oxidative metabolism to lipid storage and adipogenesis. Lipidomics confirmed aberrant accumulation of triacylglycerols (TAGs) and sphingolipids in Gsdme-deficient muscle. Single-cell profiling further identified divergent fibro-adipogenic progenitor (FAP) states skewed toward adipogenesis, accompanied by impaired expansion of restorative Lyve1+Cd163+Txnip+ tissue-resident macrophages (TRMs), as validated by multiplex flow cytometry. Blocking CCR2-dependent monocyte recruitment produced regenerative defects comparable with those caused by Gsdme deficiency. Myeloid-specific Gsdme reintroduction rescued TRM expansion and function and curbed FAP adipogenic reprogramming, whereas FAP-specific expression proved ineffective. Mechanistically, IL-18 downstream of GSDME-dependent signaling engaged KLF4/JUN signaling in TRMs, sustaining their reparative and lipid-clearing capacity. This GSDME–IL-18–TRM axis was compromised in aged muscle, yet exogenous IL-18 reversed myosteatosis and accelerated regeneration. Together, these findings suggest that GSDME-dependent pyroptotic signaling can act as a metabolic checkpoint that sustains TRM-driven lipid homeostasis to support muscle regeneration.
Authors
Qi Cao, Jian Liu, Gang Huang, Su-Yuan Wang, Guo-Dong Lu, Yong Huang, Yi-Ting Chen, Zhen Zhang, Jiang-Tao Fu, Si-Jia Sun, Xiao-Fei Chen, Chunlin Zhuang, Chunquan Sheng, Fu-Ming Shen, Dong-Jie Li, Pei Wang
Abstract
Circulating monocyte-derived macrophages (MDMø) rapidly invade the brain after stroke, exerting both detrimental and beneficial effects. Elucidating mechanisms that mediate detrimental properties of MDMø may identify therapeutic strategies to divert MDMø from destructive phenotypes, while preserving their favorable effects. Toward this goal, the current study explores the function of Galectin-3 (GAL3) in MDMø and elucidates mechanisms whereby MDMø-derived GAL3 exacerbates stroke injury. In the acutely injured brain, GAL3 expression was upregulated primarily within MDMø. Global KO of GAL3 reduced brain infarcts in the short term but did not sustain long-term positive outcomes. Using BM chimera mice, macrophage transplantation, and myeloid cell–specific GAL3-KO (LysMCre+/–Lgals3fl/fl) mice, we demonstrated that GAL3 in MDMø mediated acute infarct expansion after stroke. Coculturing brain lysate–treated, BM-derived macrophages (BMDMs) with oxygen glucose deprivation–challenged neurons induced neurotoxicity that was mitigated by the cell-permeable, selective GAL3 inhibitor TD139. GAL3 triggered cathepsin induction and lysosomal leakage in BMDMs, leading to inflammasome activation. Systemic and transient TD139 treatment in the acute injury phase reduced infarcts, tempered neuroinflammation, and improved long-term neurological outcomes. Therefore, MDMø-derived GAL3 represents a drug target that could be accessed in peripheral blood to potentially mitigate post-stroke brain injury.
Authors
Miao Wang, Zhentai Huang, Zhihong Du, Jiajing Shan, Qing Ye, Lingxiao Lu, Ming Jiang, Fei Xu, Ziyang Liu, David J.R. Fulton, Rehana K. Leak, Babak Razani, Jun Chen, Xiaoming Hu
Abstract
SLC13A5 citrate transporter disorder is a rare epileptic encephalopathy caused by loss-of-function pathogenic variants in the SLC13A5 gene. Loss of sodium/citrate cotransporter (NaCT) function causes a severe early-life epilepsy resulting in lifelong developmental disabilities and increased extracellular citrate. Current antiseizure medications may reduce seizure frequency, yet more targeted treatments are needed to address the epileptic and neurodevelopmental SLC13A5 phenotype. We performed preclinical studies in SLC13A5-deficient (KO) mice evaluating phenotype rescue with adeno-associated virus (AAV) vector carrying a functional copy of the human SLC13A5 gene (AAV9/SLC13A5). Cerebrospinal fluid delivery of AAV9/SLC13A5 decreased extracellular citrate levels, normalized electrophysiologic and sleep architecture abnormalities, and restored resistance to chemically induced seizures and death. Treatment benefits were achieved with administration during early brain development and in young adult mice, indicating therapeutic efficacy across developmental and postdevelopmental stages. Comparison of delivery routes in young adult KO mice showed that higher brain targeting achieved with intra–cisterna magna delivery resulted in greater treatment benefit as compared with intrathecal lumbar puncture delivery. Together, these results support further development of AAV9/SLC13A5 for treating SLC13A5 citrate transporter disorder.
Authors
Lauren E. Bailey, Raegan M. Adams, Morgan K. Schackmuth, Irvin T. Garza, Krishanna Knight, Sydni K. Holmes, Meghan M. Eller, MinJae Lee, Rachel M. Bailey
Abstract
Prion diseases are a family of transmissible, neurodegenerative conditions caused by misfolded proteins called prions. Human cerebral organoids can be infected with prions from sporadic Creutzfeldt-Jakob Disease (sCJD) brain tissue. Initial experiments indicated that the cerebral organoids may be able to differentiate biological properties of different sCJD subtypes. If so, it would be possible to investigate the pathogenic similarities and differences. Herein, we investigated multiple infections of cerebral organoids with 2 sCJD subtypes, comparing hallmark features of disease as well as neuronal function and health. Our results show that, while all infections produced seeding-capable prion protein (PrP), which increased from 90–180 days after infection, a sCJD subtype preference for protease-resistant PrP deposition was observed. Both subtypes caused substantial electrophysiological dysfunction in the infected organoids, which appeared uncoupled from PrP deposition. Neuronal dysfunction was associated with changes in neurotransmitter receptors that differed between the subtypes but produced the same outcome of a shift from inhibitory toward excitatory neurotransmission. Further changes indicated shared deficits in mitochondrial dynamics, and subtype influenced alterations in intracellular signaling pathways, cytoskeletal structure, and the extracellular matrix. We conclude that cerebral organoids demonstrate both common mitochondrial deficits and sCJD subtype–specific changes in neurotransmission and organoid architecture.
Authors
Katie Williams, Bradley R. Groveman, Simote T. Foliaki, Brent Race, Arielle Hay, Ryan O. Walters, Tina Thomas, Gianluigi Zanusso, James A. Carroll, Cathryn L. Haigh
Abstract
Primary and metastatic brain tumors exhibit resistance to immunotherapies that demonstrate efficacy in peripheral cancer settings. While many immunotherapies aim to enhance CD8+ T cell infiltration and functionality in established tumors, identification of neoantigens support emerging immunopreventative tactics against brain cancer. Functionally potent tissue-resident memory CD8+ T cells (TRM) can be generated in the brain following peripheral infection or vaccination. However, the ability of brain TRM to prevent intracranial malignancy remains unknown. Here, mice were seeded with tumor-specific or bystander brain TRM via peripheral infection prior to depletion of circulating memory T cells (TCIRCM) and subsequent brain tumor challenge. Tumor-specific brain TRM durably protected mice against intracranial malignancy even in the absence TCIRCM. These brain TRM persisted in tumor-surviving mice and protected against a second antigen-matched challenge. Importantly, a translationally-relevant mRNA-lipid nanoparticle (LNP) vaccine phenocopied peripheral infection-induced outcomes, generating functional brain TRM that controlled tumor growth. Altogether, this work points to the utility of brain TRM in cancer immunoprevention, supporting the development of antitumor mRNA-LNP vaccines to bolster brain immunity.
Authors
Madison R. Mix, Cassie M. Sievers, Mariah Hassert, Shravan Kumar Kannan, Lecia L. Pewe, Sunny C. Huang, Rui He, Cori E. Fain, Mohammad Heidarian, Lisa S. Hancox, Sahaana A. Arumugam, Terry G. Beltz, Fang Jin, Aaron J. Johnson, Calvin S. Carter, Noah S. Butler, Aliasger K. Salem, Vladimir P. Badovinac, John T. Harty
Abstract
Complete response is rarely observed in lung cancer molecular targeted therapy, despite great clinical success. Here, we found that molecular therapy targeted toward EGFR mutant, KRAS mutant, or ALK fusion lung cancer induced cholesterol biosynthesis, which promoted cancer cells to enter dormancy and thus escape drug killing. Combined statin treatments effectively blocked cholesterol biosynthesis, prevented cancer cells from entering dormancy, and thus resulted in dramatic tumor regression. We further identified a subpopulation of cycling cancer cells that persisted during molecular targeted therapy and remained sensitive to aurora kinase inhibitors. Triple-targeting cholesterol biosynthesis, aurora kinase, and individual oncogenic drivers almost eradicated all the cancer cells. Therapy-induced cancer dormancy was mainly attributed to activation of unfolded protein response, specifically the PERK-eIF2α axis, which triggers cholesterol biosynthesis and AKT signaling. Collectively, this work uncovers an unexpected role of a therapy-induced prosurvival program in promoting cancer dormancy and provides a potentially effective strategy to prevent drug resistance.
Authors
Yikai Zhao, Yijia Zhou, Linnuo Pan, Geng G. Tian, Hsin-Yi Huang, Shijie Tang, Ming Lu, Zhangsen Zhou, Peng Zhang, Luonan Chen, Lele Zhang, Liang Hu, Hongbin Ji
Abstract
Glutathione (GSH) maintains a reduced cellular environment and is widely believed to mitigate disease-associated oxidative damage to proteins, thereby protecting against metabolic dysfunction–associated steatotic liver disease (MASLD). However, this widely accepted assumption remains largely untested because of challenges in physiologically manipulating hepatic GSH levels during disease development. Here, we have utilized liver-specific overexpression of cation transport regulator homolog 1 (Chac1), a recently identified intracellular GSH-degrading enzyme, to induce hepatic GSH depletion during MASLD progression. Contrary to canonical doctrine, GSH depletion unexpectedly protects against MASLD by substantially decreasing hepatic lipogenesis and fibrosis without triggering an oxidative stress response. Mechanistically, GSH depletion does not cause global protein oxidation but instead selectively oxidizes and destabilizes fatty acid synthase while decreasing lipogenic gene expression at the transcriptional level, collectively suppressing lipogenesis. Interestingly, Chac1 expression is decreased in livers of patients with MASLD, highlighting its potential therapeutic relevance. These findings revise the conventional view of GSH in protein redox and demonstrate that targeted redox manipulation through GSH depletion protects against MASLD.
Authors
Xiang-Yu Liu, Guoxiao Wang, Yingying Yu, Haopeng Xiao, Kentaro Oh-hashi, Xu Shi, Shuning Zheng, Robert Gerszten, C. Ronald Kahn
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Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)