Immunology
Abstract
In alcohol use disorder (AUD), duodenal macrophage number are reduced, but the underlying mechanisms and consequences for gut permeability remain unknown. Actively drinking AUD patients undergoing standardized inpatient detoxification and healthy controls were enrolled. Fasting blood samples and duodenal biopsies were analyzed using proteomics, histology, multiplex immunohistofluorescence, flow cytometry, and quantitative polymerase chain reaction. Circulating monocytes were differentiated ex vivo into macrophages to assess migration, differentiation, phagocytosis, and cytokine release following stimulation with bacterial products. Gut permeability was evaluated using urinary 51Chromium- ethylenediaminetetraacetic acid excretion, and plasma surrogate markers of microbial translocation. AUD patients showed markedly reduced duodenal macrophages despite increased circulating monocytes and tissue monocyte-attracting chemokines. AUD monocytes exhibited reduced CCR2 expression and downregulation of tissue proteins involved in adhesion and trans-endothelial migration, thereby decreasing mucosal infiltration. Early macrophage differentiation associated was impaired, with reduced CSF1, CSF2, IL-34, and CSF1 receptor expression. Despite preserved phagocytic capacity, residual tissue macrophages displayed a mixed immune phenotype with reduced expression of scavenger receptors involved in microbial responses and cytokine hyporesponsiveness to lipopolysaccharide and peptidoglycan. Reduced macrophage numbers correlated with increased intestinal permeability and markers of microbial translocation. These results link disruption of the duodenal monocyte-macrophage axis to intestinal barrier failure in AUD.
Authors
Yifan Hu, Jerome Ambroise, Luca Maccioni, Laure-Alix Clerbaux, Caroline Bouzin, Bernd Schnabl, Peter Stärkel
Abstract
Basal-like double-negative prostate cancer (DNPC) and triple-negative breast cancer (TNBC) are aggressive tumors with few targeted treatment options, raising the question of whether a shared, druggable cell-surface antigen can be leveraged for effective immunotherapy. Here, we integrated analyses of independent bulk and single-cell transcriptomic datasets with mechanistic and preclinical therapeutic studies to evaluate CDH3 (P-cadherin) as a candidate target in basal-like disease. CDH3 expression was consistently enriched in basal-like subtypes across prostate and breast cancer cohorts and was preferentially expressed in basal epithelial tumor compartments. Mechanistically, CDH3 expression was governed by a YAP1–WNT5A/ROR2 signaling axis, linking basal subtype gene expression to non-canonical Wnt signaling. To exploit this target, we evaluated both a CDH3-directed antibody-drug conjugate (ADC) and CDH3-specific chimeric antigen receptor (CAR)-T cells. The ADC exhibited antigen-dependent internalization and cytotoxicity in vitro and reduced metastatic tumor burden in vivo. CDH3 CAR-T cells showed antigen-specific activation and tumor cell killing in vitro and improved tumor control and survival in metastatic prostate and breast cancer xenograft models, with additional benefit when combined with PD-1 blockade (nivolumab). Together, these findings establish CDH3 as a clinically relevant and therapeutically actionable target and support CDH3-directed ADC and CAR-T strategies for aggressive, basal-like DNPC and TNBC.
Authors
Guoqiang Liu, Shiyu Wang, Ziyu Zeng, Loan Duong, Jing Yang, Nipuni Barupala, Yun Zhao, Sharif Rahmy, Shan Feng, Xiaotian Chi, Ariana Arce, Linchuan Jia, Jun Wan, Liang Cheng, Xuemin Lu, Xin Lu
Natural killer cells from children with obesity exhibit a persistent ‘trained’ response to influenza
Abstract
Children and adults living with obesity have more severe influenza A virus (IAV) infection, but the underlying mechanisms are unclear. Natural killer (NK) cells play a key role in the innate immune responses to IAV and clearance of IAV-infected cells. ‘Trained immunity’ of NK cells (and other innate immune cells) refers to an initial stimulus (i.e. obesity) inducing metabolic and epigenetic changes that make these cells hyperinflammatory upon restimulation (i.e. with IAV). Here, we tested whether obesity in children induces trained immunity in NK cells. We have show that NK cells from children with obesity have a hyperinflammatory ‘trained’ phenotype, with increased expression of activation markers TLR2, CCR2, TLR4, HLA-DR and CD11b compared to children without obesity. Furthermore, we have demonstrate that NK cells from children with obesity have a heightened ex vivo IFN-γ response to stimulation with IAV (A/Auckland/4/2009, H1N1 and HKx31, H3N2) and epigenetic changes consistent trained immunity. A decrease in BMI z-score following weight-management was not associated with a reduction in the IFN-γ response, suggesting that weight loss is not sufficient to normalise NK cell function. Better understanding of obesity-related immune modulation is critical for development of new therapeutic strategies and improving outcomes in future IAV pandemics
Authors
Ellesandra C. Noye, Megan Airey, Danielle K. Longmore, Hui Xu, David Chisanga, Christoph Saner, Meagan Carney, Meg Kaegi, Hiu On Man, M. Zeeshan Chaudhry, Liam C. Kealy, Julian D. J. Sng, Isabelle Hocking, Melanie Wu, Georgina McCallum, Gabrielle T. Belz, Kim L. Good-Jacobson, David Burgner, Siroon Bekkering, Kirsty Short
Abstract
Targeted injury to the biliary epithelium and impaired bile flow are central mechanisms underlying childhood cholangiopathies. In biliary atresia (BA), immune-mediated cholangiocyte injury drives progressive bile duct obstruction, yet epithelial-intrinsic programs regulating injury susceptibility remain incompletely defined. Here, we modeled virus-epithelium interactions using rhesus rotavirus (RRV) infection of human liver-derived cholangiocyte organoids from normal donors (NCO) and infants with BA at diagnosis (BACO-Dx) or transplantation (BACO-Tx). Compared with NCO, BA organoids displayed baseline defects in tight junction architecture and barrier function, with prominent epithelial disruption and apoptosis following RRV exposure. Transcriptomic profiling revealed that while NCO and BACO-Dx mounted predominantly interferon-associated antiviral responses, BACO-Tx exhibited an expanded inflammatory program characterized by enrichment of NF-κB (RELA/NFKB1) regulatory network at baseline and amplified by infection. Inhibition of NF-κB signaling with the hydrogen sulfide donor GYY4137 restored organoid growth, improved tight junction organization, reduced permeability, and attenuated RRV-induced apoptosis. In the murine BA model, GYY4137 improved disease severity, preserved bile duct architecture, and protected epithelial junctional integrity while limiting cholangiocyte apoptosis. These findings identify an epithelial NF-κB-predominant program as a key determinant of intrinsic susceptibility to viral injury in BA and support targeting cholangiocyte NF-κB signaling to suppress disease progression.
Authors
Wenqi Li, Ashley Fonseca-Mejia, Reena Mourya, Pavithra Sudhakara, Pranavkumar Shivakumar, Jorge A. Bezerra
Abstract
Bone metastases are a frequent complication of breast cancer, leading to reduced quality of life and increased morbidity. By intratibially injecting PyMT breast cancer cells in mice, we showed that the presence in the gut microbiome of segmented filamentous bacteria (SFB), a taxon that induces IL-17–producing Th17 cells and TNF-α (TNF)–producing T cells (TNF+ T cells), accelerated intraosseous tumor growth. SFB increased the activity of parathyroid hormone–related protein (PTHrP), a known driver of breast cancer bone metastasis produced by breast cancer cells. SFB promoted the PTHrP-induced expansion of intestinal Th17 cells and TNF+ T cells, their migration to bone marrow (BM) in tumor-bearing bones, and the BM expression of TNF, IL-17, and RANKL, cytokines that promote bone resorption. Demonstrating the functional relevance of IL-17 and TNF, silencing of either IL-17 or TNF blunted the growth of bone lesions in SFB+ mice. Thus, the abundance of SFB in the microbiome of mice and of SFB-like taxa in humans may determine the potency of PTHrP and the rate of growth of bone metastasis in breast cancer. Targeting the gut microbiota may represent a novel therapeutic strategy for breast cancer bone metastasis.
Authors
Nand K. Roy, Subhashis Pal, Hamid Y. Dar, Sanchiti Patil, M. Neale Weitzmann, Roberto Pacifici
Abstract
Castleman disease (CD) is an inflammatory disorder characterized by lymphadenopathy with distinctive histologic features, yet its pathophysiology remains poorly understood. This delays diagnoses and limits treatments, leading to additional morbidity and mortality. We used single- cell and spatial transcriptomics to characterize lymph nodes from unicentric CD (UCD) compared with non-specific inflammatory lymphadenopathies. While hematopoietic cells showed few compositional or transcriptional differences, lymph node stromal cells exhibited marked alterations in UCD, most notably an increased abundance of vascular smooth muscle cells (VSMCs) and broadly increased stromal signaling activity. A generalized linear model distinguished histologically indeterminate lymph nodes resembling UCD from non-specific inflammation most accurately using stromal rather than hematopoietic cell composition. Immunohistochemical staining for the VSMC marker CD146 (Melanoma Cell Adhesion Molecule, MCAM) further discriminated UCD from other causes of lymphadenopathy. Together, these findings identify increased VSMC abundance as a hallmark of UCD and suggest that this stromal signature can be leveraged to improve pathologic diagnosis and patient stratification.
Authors
Joshua D. Brandstadter, Samuel Meili, Joseph Zinski, Hung-Wei Cheng, Dorottya Laczko, Michael V. Gonzalez, Subin S. George, Megan S Lim, Adam Bagg, Yves Stanossek, Lucas Onder, Mechthild Lϋtge, Angelina De Martin, Bridget Austin, Melanie Mumau, Katherine S. Forsyth, Vinodh Pillai, Antonio Ferreira, Jon C. Aster, Sunita Nasta, Burkhard Ludewig, David C. Fajgenbaum, Ivan Maillard
Abstract
BACKGROUND. Despite the availability of effective vaccines, pneumococcal disease remains a major global health concern. Pneumococcal conjugate vaccines (PCVs) have progressively increased in valency, a change associated with reduced antibody titers against individual polysaccharide antigens. Whether increasing vaccine valency affects B cell responses through antigenic competition remains incompletely understood. We investigated pneumococcal polysaccharide-specific B cell responses in peripheral blood and vaccine draining lymph nodes following vaccination with PCV13. METHODS. Healthy adults (n = 5) received PCV13. Peripheral blood and lymph node fine needle aspirations (FNA) were collected longitudinally at baseline and after vaccination. Pneumococcal polysaccharide-specific B cell responses, polysaccharide-specific antibody responses and opsonophagocytic activity were analyzed in peripheral blood and draining lymph nodes. RESULTS. Antigen-specific memory B cells in peripheral blood expanded rapidly and peaked 2 weeks after vaccination. In contrast, germinal center formation in lymph nodes was delayed, peaking at 4 weeks. Germinal center B cell responses were dominated by a limited number of polysaccharide specificities, whereas the expansion of memory B cells in peripheral blood was more evenly distributed across specificities. Polysaccharide-specific antibodies followed similar dynamics in plasma and FNA supernatant. CONCLUSION. Adult immune responses to PCV are characterized by robust extrafollicular memory B cell expansion and delayed germinal center responses. The restricted specificity of germinal center B cells provides evidence for antigenic competition during germinal center formation, with potential implications for the design and immunogenicity of multivalent vaccines. TRIAL REGISTRATION. EU CT number 2022-501519-15-00. FUNDING. LUMC PhD Fellowship, ZonMW Vidi and ZonMW Clinical Fellowship.
Authors
David W. de Vos, Marina Johnson, Dennis Hoving, Giovanni E. Loe-Sack-Sioe, Catherina Kienhuis, Els L. van Persijn van Meerten, David Goldblatt, Leo G. Visser, Anna H.E. Roukens, Simon P. Jochems
Abstract
An immunosuppressive, macrophage-rich tumor microenvironment (TME) is a barrier to immunotherapy across many cancers including osteosarcoma, where immunotherapy has largely failed. cGAS-STING agonism has been explored to inflame such tumors, yet the mechanisms of STING-mediated TME remodeling remain poorly understood, especially in sarcomas. Using multi-modal single cell analysis, we show that systemic STING agonism in osteosarcoma triggers a myeloid-predominant inflammatory response and rapid tumor necrosis, followed by a T cell-mediated response, immunologic memory, and long-term cure in some models. Within two hours of treatment, STING agonism induces pro-inflammatory interferon programs in tumor-associated macrophages and monocytes, with additional contributions from endothelial cells. Efficacy persists in the absence of tumor-intrinsic STING or IFNAR, confirming that the therapeutic axis resides within the host TME rather than the tumor cell compartment. While cGAS-STING is frequently repressed in human osteosarcoma models of aggressive disease, a STING activation gene signature predicts survival in newly diagnosed patients, suggesting that this pathway is engaged during tumor progression. Together, these data identify an opportunity to exploit the myeloid compartment of osteosarcoma with STING pathway therapies, charting a path forward for engaging the TME to secure long term cure in an aggressive malignancy still treated with highly toxic chemotherapy.
Authors
Elizabeth P. Young, Christine A. Johnson, Alex G. Lee, Douglass Morris II, Georgia M. Edmondson, Alfonso G. Ramirez-Ristori, Jessica Tsui, Marcus R. Breese, Juan Antonio Camara Serrano, Courtney R. Schott, Clare L. Abram, Stanley G. Leung, Leanne C. Sayles, Aafrin M. Pettiwala, Vanessa S. Gutierrez Vera, Clifford A. Lowell, Alexis J. Combes, Troy A. McEachron, E. Alejandro Sweet-Cordero
Abstract
Obesity is a chronic progressive disease strongly linked to numerous comorbidities. This is underpinned by a chronic inflammatory environment and significant immune dysregulation. γδ T cells are unconventional T cells that display innate and adaptive characteristics, the predominant one being their independence of MHC restriction. In humans, γδ T cells represent up to 5% of the peripheral blood T cell compartment and are capable of rapidly producing a range of effector cytokines and driving cytotoxic responses. This is critical for protection from both bacterial and viral infections. We investigated circulating γδ T cell metabolic and functional responses in cohorts of people living with obesity (PWO) and people without obesity. We showed that PWO have reduced Vδ2+ T cell frequencies, and their effector responses are diminished following stimulation. We identified that the CD98-LAMTOR5-mTORC1 metabolic axis was critical for functional responses, and demonstrated significant defects in each component of this axis in PWO. Furthermore, STAT5 the initiator of amino acid metabolism was also decreased in PWO. Finally, we showed restoration of this metabolic axis after bariatric surgery, combined with robust improvements in functional responses. Collectively, our data highlighted that obesity drives a reversible dysregulation of Vδ2+ T cells by disrupting cellular metabolism.
Authors
Ciara L. Flynn, Eimear K. Ryan, Cian Davis, Czara A. Kennedy, Katherine G. Egan, Aimee Brennan, Philip Mc Entee, Kirstan Murphy, Niamh Lynam-Lennon, Linda V. Sinclair, Nicholas Jones, Donal O'Shea, Helen M. Heneghan, Andrew E. Hogan
Abstract
The inflammasome is an innate immune complex responsible for aberrant interleukin-1β (IL-1β) signaling in numerous chronic inflammatory diseases, including gout and Alzheimer’s disease. The inflammasome is composed of several proteins, including the apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC). We developed vaccines targeting various regions of ASC using a Qβ virus-like particle (VLP) platform to assess the efficacy of anti-ASC antibodies for inhibiting inflammasome activity. Using a mouse model of gout, we assessed seven vaccines targeting mouse ASC for their ability to reduce inflammasome activation and neutrophil responses. Three vaccines targeting different regions of the ASC protein (pyrin domain, linker region, and the caspase activation and recruitment domain) successfully targeted ASC, reduced IL-1β, and reduced neutrophil activation. Combining these three vaccines into one cocktail vaccine yielded similar efficacy in the gout model with a favorable safety profile. The combined ASC vaccine also reduced inflammasome levels and pathologically phosphorylated tau in a transgenic mouse model of tauopathy and did not significantly impair host immune responses to bacterial or viral infections. Thus, Qβ-VLP vaccines against ASC can neutralize pathological inflammasome activity across multiple inflammatory disease models.
Authors
Jonathan Hulse, Zachary Villaseñor, Samuel Kress, Kathryn Sánchez, Julianne Peabody, Kimberly A. Morrissey, Alan McNolty, Benjamin Lantz, Laura Gonzalez Bosc, Judy L. Cannon, Seth Daly, Bryce Chackerian, Kiran Bhaskar
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