Tubulin tyrosine ligase variant perturbs microtubule tyrosination in hypertrophic cardiomyopathy
Jain et al. report that a tubulin tyrosine ligase mutant causes hypertrophy in patient-derived and CRISPR gene-edited induced pluripotent stem cell–derived (iPSC-derived) cardiomyocytes due to perturbation of tubulin tyrosination. The cover image shows patient iPSC-derived cardiomyocytes displaying the meshwork of detyrosinated α-tubulin (black).
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Research Articles
Ameer Y. Taha, … , Danielle J. Harvey, Pamela J. Lein Published May 13, 2025
Citation Information: JCI Insight. 2025;10(15):e175917. https://doi.org/10.1172/jci.insight.175917.
×Abstract
BACKGROUND Traffic-related air pollution (TRAP) is a risk factor for Alzheimer disease (AD), where unresolved brain inflammation has been linked to deficits in the levels of free lipid mediators that enable the resolution of inflammation. It is unknown whether these deficits are due to reductions in esterified lipid pools, the main source of free bioactive proresolving lipids in the brain, and whether they are related AD pathophysiology.METHODS This unknown was tested by measuring brain esterified lipid mediators and pathogenic markers of AD in TgF344-AD and WT male and female rats exposed to filtered air or TRAP for 14 months; it was also tested in human postmortem prefrontal cortex of individuals with or without AD.RESULTS Significant reductions in proresolving lipid mediators esterified to neutral lipids and/or phospholipids were seen in AD and TRAP-exposed female rats, where levels were associated with inflammation, synaptic loss, and impaired glucose metabolism. Lower esterified proresolving lipid mediator concentrations were associated with older age in prefrontal cortex of humans with AD compared with controls.CONCLUSION Impaired resolution in AD is due to depletion of esterified proresolving lipid pools that supply the brain with free bioactive mediators involved in inflammation resolution. TRAP exposure alters the same esterified resolution pathways, reflecting convergent mechanisms underlying AD.
Authors
Ameer Y. Taha, Qing Shen, Yurika Otoki, Nuanyi Liang, Kelley T. Patten, Anthony E. Valenzuela, Christopher D. Wallis, Douglas J. Rowland, Abhijit J. Chaudhari, Keith J. Bein, Anthony S. Wexler, Lee-Way Jin, Brittany N. Dugger, Danielle J. Harvey, Pamela J. Lein
Yun-Han Jiang, … , Sai Chen, Ying-Qiang Guo Published July 8, 2025
Citation Information: JCI Insight. 2025;10(15):e182050. https://doi.org/10.1172/jci.insight.182050.
×Abstract
Idiopathic pulmonary fibrosis (IPF) is a severe, diffuse, progressive, and fibrosing interstitial disease leading to respiratory failure and death in the absence of organ transplantation. Substantial evidence has confirmed the pivotal role of fibroblasts in the progression of IPF, yet effective therapeutic options are scarce. Single-cell transcriptomics profiling revealed that among the diverse fibroblast subsets, FAP1+ alveolar fibroblasts (AFs) were pivotal for the progression of IPF. On the basis of these findings, we developed FAP1-targeting chimeric antigen receptor cytotoxic effector regulatory T cells (CAR-cTregs), which leveraged the targeted killing advantage of the currently trending CAR-based immunotherapy for tumors and incorporated the immunosuppressive functions of Tregs to mitigate the inflammation caused by both the disease itself and CAR-T cell infusion. Accordingly, CAR-cTregs were constructed to effectively eliminate FAP1+ fibroblasts in vitro. This cytotoxic effect could be abrogated by inhibitors of the granzyme B/perforin pathway. In the bleomycin-induced PF model, CAR-cTregs were found to reverse fibrosis characterized by diminished recruitment of fibrocytes and improved remodeling of epithelial cells. Together, our results demonstrate that CAR-cTregs can serve as a promising therapeutic option for IPF and provide an alternative strategy for treating multiple chronic inflammatory diseases by inducing both cytotoxicity and immunosuppression.
Authors
Yun-Han Jiang, Meng Zhou, Meng-Di Cheng, Sai Chen, Ying-Qiang Guo
Jennifer M. Mariano, … , Christopher Ward, Aikaterini Kontrogianni-Konstantopoulos Published June 26, 2025
Citation Information: JCI Insight. 2025;10(15):e182471. https://doi.org/10.1172/jci.insight.182471.
×Abstract
Dominant missense mutations in MYBPC1, the gene encoding the essential sarcomeric slow Myosin Binding Protein-C (sMyBP-C), are associated with Myotrem, a new, early-onset congenital myopathy characterized by muscle weakness, hypotonia, skeletal deformities, and myogenic tremor. Importantly, the clinical manifestation of Myotrem in mid- and late adulthood is unknown. Using the Myotrem MYBPC1 E248K–knock-in (E248K-KI) murine model, we interrogated contractile performance of soleus, gastrocnemius, and tibalis anterior (TA) muscles in both male and female mice in mid- (12 months) and late (24 months) adulthood. Our findings show that the phenotypic manifestation of E248K Myotrem differs across muscle type, sex, and age. While KI soleus muscle consistently exhibited contractile impairment across both sexes and ages, KI gastrocnemius muscle displayed preserved force production. Interestingly, TA muscle showed a sex- and age-specific effect with preserved function through 12 months in both sexes and a sharp decline at 24 months solely in males. Quantitative analysis of TA sarcomeric organization uncovered structural deficits coinciding with contractile dysfunction, supporting the notion that sMyBP-C serves a primarily structural role in skeletal muscle. Collectively, our studies reveal that aging affects the E248K Myotrem myopathy in a muscle- and sex-dependent fashion and show that sarcomeric disorganization accompanies contractile deterioration in affected muscles.
Authors
Jennifer M. Mariano, Humberto C. Joca, Jacob Kallenbach, Natasha Ranu, Julien Ochala, Christopher Ward, Aikaterini Kontrogianni-Konstantopoulos
Luis R. Rodríguez, … , Darrell N. Kotton, Michael F. Beers Published July 1, 2025
Citation Information: JCI Insight. 2025;10(15):e182578. https://doi.org/10.1172/jci.insight.182578.
×Abstract
Alveolar epithelial type II (AT2) cell dysfunction is implicated in the pathogenesis of familial and sporadic idiopathic pulmonary fibrosis (IPF). We previously demonstrated that expression of an AT2 cell–exclusive disease-associated protein isoform (SP-CI73T) in murine and patient-specific induced pluripotent stem cell–derived (iPSC-derived) AT2 cells leads to a block in late macroautophagy and promotes time-dependent mitochondrial impairments; however, how a metabolically dysfunctional AT2 cell results in fibrosis remains elusive. Here, using murine and human iPSC-derived AT2 cell models expressing SP-CI73T, we characterize the molecular mechanisms governing alterations in AT2 cell metabolism that lead to increased glycolysis, decreased mitochondrial biogenesis, disrupted fatty acid oxidation, accumulation of impaired mitochondria, and diminished AT2 cell progenitor capacity manifesting as reduced AT2 cell self-renewal and accumulation of transitional epithelial cells. We identify deficient AMPK signaling as a critical component of AT2 cell dysfunction and demonstrate that targeting this druggable signaling hub can rescue the aberrant AT2 cell metabolic phenotype and mitigate lung fibrosis in vivo.
Authors
Luis R. Rodríguez, Konstantinos-Dionysios Alysandratos, Jeremy Katzen, Aditi Murthy, Willy Roque Barboza, Yaniv Tomer, Sarah Bui, Rebeca Acín-Pérez, Anton Petcherski, Kasey Minakin, Paige Carson, Swati Iyer, Katrina Chavez, Charlotte H. Cooper, Apoorva Babu, Aaron I. Weiner, Andrew E. Vaughan, Zoltan Arany, Orian S. Shirihai, Darrell N. Kotton, Michael F. Beers
Urbanus Muthai Kinuthia, … , Ralf H. Adams, Thomas Langmann Published July 1, 2025
Citation Information: JCI Insight. 2025;10(15):e184465. https://doi.org/10.1172/jci.insight.184465.
×Abstract
The loss of integrity of the blood retina barrier (BRB) is a key pathological hallmark of vision-threatening complications in diabetic retinopathy (DR). Although DR is considered a microvascular disease, mounting evidence from mouse models and patients show that inflammation is closely connected with microvasculopathy. Inflammatory responses during retinal pathophysiology are often orchestrated by microglia, resident innate immune cells of the retina. However, the precise role of microglia activity during DR pathogenesis remains elusive. Here, we used an anti-PDGFRβ antibody and inducible endothelial cell–specific PDGFB-KO during postnatal development of retinal vasculature to reproduce a key feature of DR pathology in mice. In addition, we applied a minocycline therapy to modulate retinal inflammation. Postnatal depletion of pericytes or loss of PDGFB in retinal vessels altered BRB integrity and triggered secretion of angiogenic and inflammatory factors with concomitant microglia reactivity, which was sustained in retinas of adult mice. Microglia reactivity was accompanied by upregulation of disease-associated genes. Notably, minocycline attenuated the cycle of inflammatory responses in young and mature retinas, thereby preserving retinal vascular and structural integrity in mice. Together, our findings suggest that immunomodulation of microglia-driven inflammatory responses preserves retinal vasculature and maintains BRB integrity in 2 different mouse models of human DR.
Authors
Urbanus Muthai Kinuthia, Christoph Moehle, Ralf H. Adams, Thomas Langmann
×Abstract
Hypertrophic cardiomyopathy (HCM) is a hereditary heart condition characterized by either preserved or reduced ejection fraction without any underlying secondary causes. The primary cause of HCM is sarcomeric gene mutations, which account for only 40%–50% of the total cases. Here, we identified a pathogenic missense variant in tubulin tyrosine ligase (TTL p.G219S) in a patient with HCM. We used clinical, genetics, computational, and protein biochemistry approaches, as well as patient-specific and CRISPR gene-edited induced pluripotent stem cell–derived cardiomyocytes (iPSC-CMs), to demonstrate that the TTL pathogenic variant results in a reduced enzymatic activity and the accumulation of detyrosinated tubulin leading to the disruption of redox signaling, ultimately leading to HCM. Our findings highlight — for the first time to our knowledge — the crucial roles of the TTL variant in cardiac remodeling resulting in disease.
Authors
Pratul Kumar Jain, Susobhan Mahanty, Harshil Chittora, Veronique Henriot, Carsten Janke, Minhajuddin Sirajuddin, Perundurai S. Dhandapany
Abhishek Basu, … , Malliga R. Iyer, Resat Cinar Published July 3, 2025
Citation Information: JCI Insight. 2025;10(15):e187967. https://doi.org/10.1172/jci.insight.187967.
×Abstract
Pulmonary fibrosis (PF) is a life-threatening disease that requires effective and well-tolerated therapeutic modalities. Previously, the distinct pathogenic roles of cannabinoid receptor 1 (CB1R) and inducible nitric oxide synthase (iNOS) in the lungs and their joint therapeutic targeting were highlighted in PF. However, the cell-specific role of CB1R in PF has not been explored. Here, we demonstrate that CB1R in alveolar macrophages (AMs) mediates the release of anandamide into the alveoli, which promotes PF by inducing pro-fibrotic macrophages that are accessible to locally delivered antifibrotic therapy. A multitargeted therapy may improve therapeutic efficacy in PF. Pulmonary delivery of 0.5 mg/kg/d MRI-1867 (zevaquenabant), a peripherally acting hybrid CB1R/iNOS inhibitor, was as effective as systemic delivery of 10 mg/kg/d and also matched the efficacy of nintedanib in mitigating bleomycin-induced PF. A systems pharmacology approach revealed that zevaquenabant and nintedanib treatments reversed pathologic changes in both distinct and shared PF-related pathways, which are conserved in human and mouse. Moreover, zevaquenabant treatment also attenuated fibrosis and pro-fibrotic mediators in human precision-cut lung slices. These findings establish CB1R-expressing AMs as a therapeutic target and support local delivery of dual CB1R/iNOS inhibitor zevaquenabant by inhalation as an effective, well-tolerated, and safe strategy for PF.
Authors
Abhishek Basu, Muhammad Arif, Kaelin M. Wolf, Madeline Behee, Natalie Johnson, Lenny Pommerolle, Ricardo H. Pineda, John Sembrat, Charles N. Zawatsky, Szabolcs Dvorácskó, Nathan J. Coffey, Joshua K. Park, Seray B. Karagoz, Grzegorz Godlewski, Tony Jourdan, Judith Harvey-White, Melanie Königshoff, Malliga R. Iyer, Resat Cinar
Anne Cao Le, … , Grant J. Logan, Kim M. O’Sullivan Published July 9, 2025
Citation Information: JCI Insight. 2025;10(15):e188951. https://doi.org/10.1172/jci.insight.188951.
×Abstract
Extracellular DNA (ecDNA) released from injured and dying cells powerfully induces injurious inflammation. In this study we define the role of ecDNA in systemic vasculitis affecting the kidney, using human kidney biopsies and murine models of myeloperoxidase anti-neutrophil cytoplasmic antibody-associated glomerulonephritis (MPO-ANCA GN). Twice daily administration of intravenous deoxyribonuclease I (ivDNase I) in 2 models of anti-MPO GN reduced glomerular deposition of ecDNA, histological injury, leukocyte infiltration, and NETosis. Comprehensive investigation into DNase I modes of action revealed that after exposure to MPO, DNase I reduced lymph node DC numbers and their activation status, resulting in decreased frequency of MPO-specific CD4+ effector T cells (IFN-γ and IL-17A producing) and reductions in dermal anti-MPO delayed type hypersensitivity responses. To overcome the translational obstacle of the short half-life of DNase I (<5 hours), we tested an adeno-associated viral vector encoding DNase I. This method of DNase I delivery was more effective, as in addition to the histological and antiinflammatory changes described above, a single vector treatment also reduced circulating MPO-ANCA titers and albuminuria. These results indicate ecDNA is a potent driver of anti-MPO GN and DNase I is a potential therapeutic that can be delivered using gene technology.
Authors
Anne Cao Le, Virginie Oudin, Jonathan Dick, Maliha A. Alikhan, Timothy A. Gottschalk, Lu Lu, Kate E. Lawlor, Daniel Koo Yuk Cheong, Mawj Mandwie, Ian E. Alexander, A.R. Kitching, Poh-Yi Gan, Grant J. Logan, Kim M. O’Sullivan
Balraj Sandhar, … , Benny M. Chain, M. Paula Longhi Published July 1, 2025
Citation Information: JCI Insight. 2025;10(15):e189008. https://doi.org/10.1172/jci.insight.189008.
×Abstract
BACKGROUND Thymic involution with age leads to reduced T cell output and impaired adaptive immunity. However, the extent to which thymic activity persists later in life and how this contributes to immunological aging remains unclear. This study aimed to assess the presence and function of thymic tissue in older adults and identify factors influencing residual thymopoiesis.METHODS Patients aged 50 or older undergoing cardiothoracic surgery were recruited. Thymic structures within mediastinal adipose tissue were evaluated using histology, immunofluorescence, flow cytometry, T cell receptor (TCR) sequencing, and RNA sequencing. Recent thymic emigrants (RTEs) were quantified in peripheral blood and correlated with transcriptomic, epigenetic, and TCR repertoire data. Primary outcomes included thymic tissue identification, RTE frequency, and immune correlates.RESULTS Functional thymic tissue was identified in mediastinal adipose tissue of older individuals. The frequency of CD31+CD4+ T cells (RTEs) positively correlated with the presence of thymic tissue. Thymic output showed substantial heterogeneity and was influenced by sex and smoking history. Thymic activity was associated with increased TCR repertoire diversity, improved immune protection against infections, and reduced epigenetic aging. Detailed profiling uncovered functional and phenotypic heterogeneity within naive CD4+ T cell subsets shaped by thymic activity.CONCLUSION This study demonstrates that thymic function can persist into later life and is modulated by factors such as sex and smoking. These findings suggest that thymic activity during aging is heterogeneous and influenced by more than chronological age alone, with potential implications for immune competence in older adults.
Authors
Balraj Sandhar, Vishal Vyas, Daniel Harding, Roberta Ragazzini, Paola Bonfanti, Federica M. Marelli-Berg, Christopher G. Bell, Benny M. Chain, M. Paula Longhi
Wietske E. Tuinte, … , Adele D’Amico, Marta Campiglio Published August 8, 2025
Citation Information: JCI Insight. 2025;10(15):e191053. https://doi.org/10.1172/jci.insight.191053.
×Abstract
Skeletal muscle excitation-contraction (EC) coupling depends on the direct coupling between CaV1.1 on the sarcolemma and ryanodine receptor (RyR1) on the sarcoplasmic reticulum. A key regulator of this process is STAC3, a protein essential for both the functional expression of CaV1.1 and its conformational coupling with RyR1. Mutations in Stac3 cause STAC3 disorder, a congenital myopathy characterized by muscle weakness. STAC3 interacts with CaV1.1 in 2 key regions: the II-III loop and the proximal C-terminus. While the II-III loop has been previously found to be essential for skeletal muscle EC coupling, here we demonstrated that the interaction between STAC3 and the proximal C-terminus is necessary and sufficient for CaV1.1 functional expression and minimal EC coupling. In contrast, the interaction with the II-III loop is not essential for EC coupling, though it plays a facilitating role in enhancing the process. Supporting this finding, we identified a patient with STAC3 disorder carrying a mutation that deletes the domain of STAC3 involved in the II-III loop interaction. Collectively, our results established that STAC3 binding to CaV1.1 C-terminus is essential for its functional expression, whereas STAC3 interaction with the II-III loop serves to enhance the conformational coupling with RyR1.
Authors
Wietske E. Tuinte, Enikő Török, Petronel Tuluc, Fabiana Fattori, Adele D’Amico, Marta Campiglio
×Abstract
Butyrate, a microbiome-derived short-chain fatty acid with pleiotropic effects on inflammation and metabolism, has been shown to significantly reduce atherosclerotic lesions, rectify routine metabolic parameters such as low-density lipoprotein cholesterol (LDL-C), and reduce systemic inflammation in murine models of atherosclerosis. However, its foul odor, rapid metabolism in the gut and thus low systemic bioavailability limit its therapeutic effectiveness. Our laboratory has engineered an ester-linked L-serine conjugate to butyrate (SerBut) to mask its taste and odor and to coopt amino acid transporters in the gut to increase its systemic bioavailability, as determined by tissue measurements of free butyrate, produced by hydrolysis of SerBut. In an apolipoprotein E–knockout (ApoE)–/– mouse model of atherosclerosis, SerBut reduced systemic LDL-C, proinflammatory cytokines, and circulating neutrophils. SerBut enhanced inhibition of plaque progression and reduced monocyte accumulation in the aorta compared with sodium butyrate. SerBut suppressed liver injury biomarkers alanine transaminase and aspartate aminotransferase and suppressed steatosis in the liver. SerBut overcomes several barriers to the translation of butyrate and shows superior promise in slowing atherosclerosis and liver injury compared with equidosed sodium butyrate.
Authors
Taryn N. Beckman, Lisa R. Volpatti, Salvador Norton de Matos, Anna J. Slezak, Joseph W. Reda, Ada Weinstock, Leah Ziolkowski, Alex Turk, Erica Budina, Shijie Cao, Gustavo Borjas, Jung Woo Kwon, Orlando deLeon, Kirsten C. Refvik, Abigail L. Lauterbach, Suzana Gomes, Eugene B. Chang, Jeffrey A. Hubbell
Melissa R. Lyman, … , Won Jin Ho, Neeha Zaidi Published June 26, 2025
Citation Information: JCI Insight. 2025;10(15):e191595. https://doi.org/10.1172/jci.insight.191595.
×Abstract
Pancreatic ductal adenocarcinoma (PDAC) has a poor survival rate due to late detection. PDAC arises from precursor microscopic lesions, termed pancreatic intraepithelial neoplasia (PanIN), that develop at least a decade before overt disease; this provides an opportunity to intercept PanIN-to-PDAC progression. However, immune interception strategies require full understanding of PanIN and PDAC cellular architecture. Surgical specimens containing PanIN and PDAC lesions from a unique cohort of 5 treatment-naive patients with PDAC were surveyed using spatial omics (proteomic and transcriptomic). Findings were corroborated by spatial proteomics of PanIN and PDAC from tamoxifen-inducible KPC mice. We uncovered the organization of lymphoid cells into tertiary lymphoid structures (TLSs) adjacent to PanIN lesions. These TLSs lacked CD21+CD23+ B cells compared with more mature TLSs near the PDAC border. PanINs harbored mostly CD4+ T cells, with fewer Tregs and exhausted T cells than PDAC. Peritumoral space was enriched with naive CD4+ and central memory T cells. These observations highlight the opportunity to modulate the immune microenvironment in PanINs before immune exclusion and immunosuppression emerge during progression into PDAC.
Authors
Melissa R. Lyman, Jacob T. Mitchell, Sidharth Raghavan, Luciane T. Kagohara, Amanda L. Huff, Saurav D. Haldar, Sarah M. Shin, Samantha Guinn, Benjamin Barrett, Gabriella Longway, Alexei Hernandez, Erin M. Coyne, Xuan Yuan, Lalitya Andaloori, Jiaying Lai, Yun Zhou Liu, Rachel Karchin, Anuj Gupta, Ashley L. Kiemen, André Forjaz, Denis Wirtz, Pei-Hsun Wu, Atul Deshpande, Jae W. Lee, Todd D. Armstrong, Nilofer S. Azad, Jacquelyn W. Zimmerman, Laura D. Wood, Robert A. Anders, Elizabeth D. Thompson, Elizabeth M. Jaffee, Elana J. Fertig, Won Jin Ho, Neeha Zaidi
Harry Pickering, … , John R. Greenland, Daniel R. Calabrese Published July 3, 2025
Citation Information: JCI Insight. 2025;10(15):e191951. https://doi.org/10.1172/jci.insight.191951.
×Abstract
MHC class I polypeptide-related sequence B (MICB) is a ligand for NKG2D. We have shown NK cells are central to lung transplant acute lung injury (ALI) via NKG2D activation, and increased MICB in bronchoalveolar lavage predicts ALI severity. Separately, we found a MICB polymorphism (MICBG406A) is associated with decreased ALI risk. We hypothesized this polymorphism would protect against severe SARS-CoV-2 respiratory disease. We analyzed 1,036 patients hospitalized with SARS-CoV-2 infection from IMPACC. Associations between MICBG406A and outcomes were determined by linear regression or Cox proportional hazards models. We also measured immune profiles of peripheral blood and the upper and lower airway. We identified 560 major allele homozygous patients, and 426 and 50 with 1 or 2 copies of the variant allele, respectively. MICBG406A conferred reduced odds of severe COVID-19. MICBG406A homozygous participants demonstrated 34% reduced cumulative odds for mechanical ventilation or death and 43% reduced risk for mortality. Patients with MICBG406A variant alleles had reduced soluble inflammatory mediators and differential regulation of multiple immune pathways. These findings demonstrate a potentially novel association between increasing MICBG406A variant allele copies and reduced COVID-19 severity, independent of SARS-CoV-2 viral burden and humoral immunity, suggesting the NKG2D-ligand pathway as an intervention target.
Authors
Harry Pickering, Narges Alipanah-Lechner, Ernie Chen, Dylan Duchen, Holden T. Maecker, Seunghee Kim-Schulze, Ruth R. Montgomery, Chris Cotsapas, Hanno Steen, Florian Krammer, Charles R. Langelier, Ofer Levy, Lindsey R. Baden, Esther Melamed, Lauren I.R. Ehrlich, Grace A. McComsey, Rafick P. Sekaly, Charles B. Cairns, Elias K. Haddad, Albert C. Shaw, David A. Hafler, David B. Corry, Farrah Kheradmand, Mark A. Atkinson, Scott C. Brakenridge, Nelson I. Agudelo Higuita, Jordan P. Metcalf, Catherine L. Hough, William B. Messer, Bali Pulendran, Kari C. Nadeau, Mark M. Davis, Ana Fernandez Sesma, Viviana Simon, Monica Kraft, Chris Bime, David J. Erle, Joanna Schaenmann, Al Ozonoff, Bjoern Peters, Steven H. Kleinstein, Alison D. Augustine, Joann Diray-Arce, Patrice M. Becker, Nadine Rouphael, Matthew C. Altman, Steve Bosinger, Walter Eckalbar, IMPACC Network, Carolyn S. Calfee, Oscar A. Aguilar, Elaine F. Reed, John R. Greenland, Daniel R. Calabrese
×Abstract
High myopia (HM) and posterior staphyloma (PS) are major causes of vision loss worldwide. Genetic and environmental factors, especially light exposure, influence myopia. This study shows that low-density lipoprotein–related receptor type 2 (LRP2) levels are decreased in the vitreous of patients with HM and PS, and that in human donor eyes affected by PS, LRP2 expression was reduced in the neural retina and retinal pigment epithelium (RPE), with morphologic changes similar to those observed in the Foxg1-Cre-Lrp2fl/fl mouse that also develops PS. In human induced pluripotent stem cell–derived RPE cells, LRP2 silencing regulated genes involved in eye and neuronal development, visual perception, tissue remodeling, hormone metabolism, and RPE structure. Its expression increased under light exposure, particularly red light, but was downregulated by cortisol. These findings establish a link between LRP2, myopization, and environmental factors, highlighting its crucial role in nonsyndromic HM and PS. LRP2 appears to be a promising therapeutic target for HM treatment.
Authors
Kimberley Delaunay, Emilie Picard, Patricia Lassiaz, Laurent Jonet, Vidjea Cannaya, José Maria Ruiz-Moreno, Kentaro Kojima, Henrik Vorum, Bent Honoré, Jorge R. Medrano, Lasse Jørgensen Cehofski, Eric Pussard, Renata Kozyraki, Alicia Torriglia, Olivier Cases, Francine Behar-Cohen
Omar A. Osorio, … , Derek E. Byers, Jennifer Alexander-Brett Published June 24, 2025
Citation Information: JCI Insight. 2025;10(15):e193640. https://doi.org/10.1172/jci.insight.193640.
×Abstract
IL-33 is a key driver of type 2 inflammation and implicated in pathology of chronic obstructive pulmonary disease (COPD) and asthma. However, the mechanism for IL-33 secretion and regulation in the context of chronic airway disease is poorly understood. We previously reported an airway disease–associated isoform IL-33Δ34 that escapes nuclear sequestration and is tonically secreted from epithelial cells. Here, we describe how this IL-33Δ34 isoform interacts with HSP70 within cells and is targeted to secretory organelles through coordinated binding to phosphatidylserine (PS) and delivered to compartments for unconventional protein secretion (CUPS). Once secreted, extracellular HSP70 (eHSP70) in complex with IL-33Δ34 stabilizes the cytokine by inhibiting oxidation and degradation, which results in enhanced IL-33Δ34-receptor binding and activity. We further find evidence that IL-33 along with mediators of the proteostasis network HSP70, HSP90, and the Chaperonin Containing TCP1 (CCT) complex are dysregulated in human chronic airway disease. This phenomenon is reflected in the differential extracellular vesicle (EV) proteome in bronchial wash from COPD and asthma samples, which could mark disease activity and potentiate IL-33 function. This study confirms proteostasis intermediates, chiefly HSP70, as chaperones for noncanonical IL-33 secretion and activity that may be amenable for therapeutic targeting in the chronic airway diseases COPD and asthma.
Authors
Omar A. Osorio, Heather E. Raphael, Colin E. Kluender, Ghandi F. Hassan, Lucy S. Cohen, Deborah F. Steinberg, Ella Katz-Kiriakos, Morgan D. Payne, Ethan M. Luo, Jamie L. Hicks, Derek E. Byers, Jennifer Alexander-Brett
×Abstract
Preterm white matter injury (PWMI) is a leading cause of cerebral palsy and chronic neurological disabilities in premature infants. It is characterized by defects in oligodendrocyte precursor cell (OPC) differentiation and dysmyelination. Currently, there are no effective therapeutic strategies available in clinical practice. Lipid homeostasis plays a crucial role in myelin development, yet the function of Lipin1 — a key phosphatidic acid phosphatase involved in phospholipid synthesis — remains unclear. In this study, we identified a significant downregulation of Lipin1 in OPCs from PWMI mice, which impaired OPC differentiation and myelin formation. Conversely, Lipin1 overexpression in these mice promoted OPC maturation and enhanced myelin development. We found evidence that N-acetyltransferase 10 (NAT10) acts as a regulator of Lipin1 expression through RNA pull-down and mass spectrometry. NAT10-mediated N4-acetylcytidine (ac4C) modification enhanced Lipin1 mRNA stability and translation, and NAT10 knockdown in OPCs impaired myelination, highlighting its crucial role in Lipin1-mediated myelination. Our study revealed that the downregulation of Lipin1 impaired OPC differentiation and myelination in PWMI, with NAT10-mediated ac4C modification playing a critical role in regulating Lipin1 expression. These findings highlight Lipin1 and NAT10 as promising therapeutic targets for treating myelination defects in PWMI, warranting further investigation into their potential in preterm birth–related neurological disorders.
Authors
Xinyu Li, Meng Zhang, Yanan Liu, Chunjie Guo, Yiwei Liu, Lei Han, Zhaowei Feng, Xiue Wei, Ruiqin Yao
×Abstract
Mutations in Cullin-3 (CUL3) cause hypertension (HTN). We examined the role of smooth muscle cell (SMC) CUL3 in the regulation of renin gene expression. Mice with SMC-specific CUL3 deletion (S-CUL3-KO) developed severe HTN with paradoxically preserved levels of plasma angiotensin peptides and renal renin expression. Cre-recombinase was active in juxtaglomerular (JG) cells, resulting in decreased CUL3 expression. We evaluated components of the renin cell baroreceptor and revealed preserved Lamin A/C but decreased integrin β1 expression in S-CUL3-KO. We hypothesized that Rab proteins are involved in integrin β1 downregulation. Silencing either Rab21 or Rab5 in CUL3-deficient HEK293 cells increased integrin β1 protein. Coimmunoprecipitation revealed a direct interaction between Rab5 and CUL3. CUL3 deficiency increased Rab5, suggesting it is regulated by a CUL3-mediated mechanism and that CUL3 deficiency results in loss of Rab protein turnover, leading to enhanced integrin β1 internalization. We conclude that the loss of integrin β1 from JG cells impairs the mechanosensory function of the renin cell baroreceptor, which underlies the persistent renin expression observed in hypertensive S-CUL3-KO mice. These findings provide insights into the molecular mechanisms of HTN, revealing that dysregulation of Rab proteins and integrin β1 in the kidney due to CUL3 deficiency contributes to the development of HTN.
Authors
Daria Golosova, Gaurav Kumar, Ko-Ting Lu, Patricia C. Muskus Veitia, Ana Hantke Guixa, Kelsey K. Wackman, Eva M. Fekete, Daniel T. Brozoski, Justin L. Grobe, Maria Luisa S. Sequeira-Lopez, R. Ariel Gomez, Pablo Nakagawa, Curt D. Sigmund
×Abstract
The Z variant (Glu342Lys) causes alpha-1 antitrypsin (AAT) to self-assemble into polymer chains that accumulate within hepatocytes, causing liver disease and exposing a cryptic epitope recognized by the 2C1 monoclonal antibody (mAb). They can be blocked by the small molecule GSK716 (‘716) that stabilizes an intermediate on the polymerization pathway. We have characterized 23 mutants of AAT in a cellular model to establish: (a) their ability to form intracellular polymers, (b) whether polymer formation could be prevented by ‘716, and (c) whether the polymers expose the 2C1 cryptic epitope. Most of the variants, including Mprocida (Leu41Pro), Mherleen (Pro369Leu), Mduarte (Asp256Val), Lfrankfurt (Pro255Thr), Yorzinuovi (Pro391His), Mwurzburg (Pro369Ser), and p.289S accumulated as intracellular polymers. Eleven formed polymers that were resistant to ‘716, including Mprocida, Mmalton (ΔPhe51), Lfrankfurt, Mduarte, S (Glu264Val), Mherleen, and Yorzinuovi. The ‘716 resistant mutants localize to a region of the AAT molecule separate from the binding site of the small molecule and form polymers that are less well recognized by the 2C1 mAb. They are fully recognized by a novel 8A7 mAb that we developed to have a broader specificity. Our data suggest that individuals with these mutations are unlikely to benefit from treatment with ‘716 or its derivatives.
Authors
Riccardo Ronzoni, Ibrahim Aldobiyan, Elena Miranda, Narinder Heyer-Chauhan, Emma L.K. Elliston, Juan Pérez, Annamaria Fra, James A. Irving, David A. Lomas
Mohammad Arif Rahman, … , Mark G. Lewis, Genoveffa Franchini Published August 8, 2025
Citation Information: JCI Insight. 2025;10(15):e194633. https://doi.org/10.1172/jci.insight.194633.
×Abstract
Exposure to Bacillus Calmette-Guérin (BCG) or Canarypox ALVAC/Alum vaccine elicits pro- or antiinflammatory innate responses, respectively. We tested whether prior exposure of macaques to these immunogens protected against SARS-CoV-2 replication in lungs and found more efficient replication control after the pro-inflammatory immunity elicited by BCG. The decreased virus level in lungs was linked to early infiltrates of classical monocytes producing IL-8 with systemic neutrophils, Th2 cells, and Ki67+CD95+CD4+ T cells producing CCR7. At the time of SARS-CoV-2 exposure, BCG-treated animals had higher frequencies of lung infiltrating neutrophils and higher CD14+ cells expressing efferocytosis marker MERTK, responses correlating with decreased SARS-CoV-2 replication in lung. At the same time point, plasma IL-18, TNF-α, TNFSF-10, and VEGFA levels were also higher in the BCG group and correlated with decreased virus replication. Finally, after SARS-CoV-2 exposure, decreased virus replication correlated with neutrophils producing IL-10 and CCR7 preferentially recruited to the lungs of BCG-vaccinated animals. These data point to the importance of the spatiotemporal distribution of functional monocytes and neutrophils in controlling SARS-CoV-2 levels and suggest a central role of monocyte efferocytosis in curbing replication.
Authors
Mohammad Arif Rahman, Katherine C. Goldfarbmuren, Sarkis Sarkis, Massimiliano Bissa, Anna Gutowska, Luca Schifanella, Ramona Moles, Melvin N. Doster, Hanne Andersen, Yogita Jethmalani, Leonid Serebryannyy, Timothy Cardozo, Mark G. Lewis, Genoveffa Franchini
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Abstract
BACKGROUND. Glucagon-like peptide-2 (GLP-2) analogs are used clinically to enhance nutrient absorption in patients with short bowel syndrome (SBS); however, the precise mechanism remains unclear. To address this, the study aimed to clarify the dynamics of intestinal epithelial cells and immune cells in patients with SBS treated with GLP-2 analogs. METHODS. Five male patients diagnosed with SBS, all of whom received treatment with the GLP-2 analog teduglutide, were included in the study. We conducted longitudinal single-cell RNA sequencing (scRNA-seq) analysis of intestinal tissue from SBS patients over a year, integrating microbiome composition analysis. RESULTS. After treatment, the alpha diversity of the gut microbiome increased, indicating a more varied microbial environment. ScRNA-seq analysis revealed a reduction of T helper 2 cells and an increase in regulatory T (Treg) cells, suggesting a shift towards an immunoregulatory intestinal environment. Additionally, nutrient-absorbing enterocyte-Top2 and middle clusters expanded, enhancing the absorption capacity, whereas major histocompatibility complex class I/II-expressing enterocyte-Top1 cells declined, potentially modulating immune responses. CONCLUSION. The study findings indicate that GLP-2 analogs reshape intestinal immunity and microbiota, fostering a less inflammatory environment while promoting nutrient uptake efficiency. These insights offer a deeper understanding of the role of GLP-2 analogs in gut adaptation and provide a foundation for refining clinical strategies for SBS treatment. FUNDING. This work was supported by Sakaguchi Memorial Foundation, Grants-in-Aid from the Japanese Society for the Promotion of Science (JSPS) (21K18272, 23H03665, 23H02899, 23K27590, 25K22627, 23K08037), JST FOREST(21457195), and the Takeda Japan Medical Office Funded Research Grant 2022.
Authors
Yumi Kudo, Kentaro Miyamoto, Shohei Suzuki, Akihiko Chida, Anna Tojo, Mai Hasegawa, Arina Shigehara, Ikuko Koya, Yoshinari Ando, Masayasu Sato, Aya Kondo, Tomoko Kumagai, Harunori Deguchi, Yoshiki Sugiyama, Yoko Ito, Koji Shirosaki, Satoko Yamagishi, Yutaro Maeda, Hiroki Kanamori, Motohiro Kano, Mototoshi Kato, Hanako Tsujikawa, Yusuke Yoshimatsu, Kaoru Takabayashi, Koji Okabayashi, Takanori Kanai, Naoki Hosoe, Motohiko Kato, Jonathan Moody, Chung-Chau Hon, Tatsuo Kuroda, Yohei Yamada, Akihiro Fujino, Tomohisa Sujino
Abstract
Pathological cardiac remodeling is associated with the reactivation of fetal genes, yet the extent of the heart’s fetal gene program and its impact on proteome compositions remain incompletely understood. Here, using a new proteome-wide protein ratio quantification strategy with mass spectrometry, we identify pervasive isoform usage shifts in fetal and postnatal mouse hearts, involving 145 pairs of highly homologous paralogs and alternative splicing-derived isoform proteins. Proteome-wide ratio comparisons readily rediscover hallmark fetal gene signatures in muscle contraction and glucose metabolism pathways, while revealing novel isoform usage in mitochondrial and gene expression proteins, including PPA1/PPA2, ANT1/ANT2, and PCBP1/PCBP2 switches. Paralogs with differential fetal usage tend to be evolutionarily recent, consistent with functional diversification. Alternative splicing adds another rich source of fetal isoform usage differences, involving PKM M1/M2, GLS-1 KGA/GAC, PDLIM5 long/short, and other spliceoforms. When comparing absolute protein proportions, we observe a partial reversion toward fetal gene usage in pathological hearts. In summary, we present a ratiometric catalog of paralogs and spliceoform pairs in the cardiac fetal gene program. More generally, the results demonstrate the potential of applying the proteome-wide ratio test concept to discover new regulatory modalities beyond differential gene expression.
Authors
Yu Han, Shaonil Binti, Sara A. Wennersten, Boomathi Pandi, Dominic C.M. Ng, Edward Lau, Maggie P.Y. Lam
Abstract
Anemia is a common and disabling complication of chronic kidney disease (CKD). Current therapies can be burdensome, and full correction of anemia is limited by cardiovascular side effects. New approaches that may offer additional therapeutic options are needed. We explored the anti-anemic effects of erythroferrone, an erythroid hormone that induces iron mobilization by suppressing the master iron-regulatory hormone hepcidin. In a preclinical murine model of adenine-induced CKD, transgenic augmentation of erythroferrone mobilized iron, increased hemoglobin concentrations by approximately 2 g/dl, and modestly improved renal function without affecting systemic or renal inflammation, fibrosis, or markers of mineral metabolism. This study supports the concept that therapeutic augmentation of erythroferrone is a promising approach for alleviating CKD-associated anemia.
Authors
Brian Czaya, Joseph D. Olivera, Moya Zhang, Amber Lundin, Christian D. Castro Andrade, Grace Jung, Mark R. Hanudel, Elizabeta Nemeth, Tomas Ganz
Abstract
Regulatory T cells (Tregs) are essential for peripheral tolerance and depend on TCR and IL-2R signaling for their homeostasis and function. In mice, IL-2-dependent BLIMP-1 contributes to Treg homeostasis. BLIMP-1 is a major transcriptional hub in human Tregs, but its mechanisms of action remain undefined. Here, using CRISPR/Cas9 ablation, we show that BLIMP-1 limits human Treg proliferation, but supports IL-10, CTLA4, several immune checkpoints, including CEACAM1, and Treg functional activity. BLIMP-1 restrains Treg expansion to IL-2 by downregulating CD25 and IL-2R signaling, and by enhancing CEACAM1 expression, which in turn inhibits responsiveness to CD3/CD28 signaling and activation of mTOR. Prolonged IL-2R signaling optimizes BLIMP-1 expression, supporting chromosomal opening of CEACAM1 to increased CEACAM1 expression through STAT5- and BLIMP-1-driven enhancers. Correspondingly, CEACAM1 is highly induced on Tregs from autoimmune patients undergoing low-dose IL-2 therapy, and these Tregs showed reduced proliferation. A humanized mouse model of xenogeneic graft versus host disease demonstrates that BLIMP-1 normally promotes, while CEACAM1 restrains, Treg suppressive activity. Collectively, our findings reveal that BLIMP-1 and CEACAM1 function in an IL-2-dependent feedback loop to restrain Treg proliferation and affect suppressive function. CEACAM1 also acts as a highly selective biomarker of IL-2R signaling in human T cells.
Authors
Ying Ding, Aixin Yu, Milos Vujanac, Sabrina N. Copsel, Alejandro Moro, Luis Nivelo, Molly Dalzell, Nicolas Tchitchek, Michelle Rosenzwajg, Alejandro V. Villarino, Robert B. Levy, David Klatzmann, Thomas R. Malek
Abstract
Bronchopulmonary dysplasia (BPD), a prevalent and chronic lung disease affecting premature newborns, results in vascular rarefaction and alveolar simplification. Although the vasculature has been recognized as a main player in this disease, the recently found capillary heterogeneity and cellular dynamics of endothelial subpopulations in BPD remain unclear. Here, we show Cap2 cells are damaged during neonatal hyperoxic injury, leading to their replacement by Cap1 cells which, in turn, significantly decline. Single cell RNA-seq identifies the activation of numerous p53 target genes in endothelial cells (ECs), including Cdkn1a (p21). While global deletion of p53 results in worsened vasculature, endothelial-specific deletion of p53 reverses the vascular phenotype and improves alveolar simplification during hyperoxia. This recovery is associated with the emergence of a transitional EC state, enriched for oxidative stress response genes and growth factors. Notably, this transitional EC gene signature is conserved in an aberrant capillary population identified in human BPD with pulmonary hypertension, underscoring the biological and clinical relevance of our findings. These results reveal a key role for p53 in maintaining endothelial lineage fidelity during pulmonary capillary repair following hyperoxic injury and highlight the critical contribution of the endothelium to BPD pathogenesis.
Authors
Lisandra Vila Ellis, Jonathan D. Bywaters, Amanda Ceas, Yun Liu, Jennifer M.S. Sucre, Jichao Chen
