技术资料

BackgroundCNS stromal cells,especially fibroblasts and endothelial cells,support leukocyte accumulation through upregulation of adhesion molecules and lymphoid chemokines. While chronically activated fibroblast networks can drive pathogenic immune cell aggregates known as tertiary lymphoid structures (TLS),early stromal cell activation during CNS infection can support anti-viral T cells. However,the cell types and factors driving early stromal cell activation is poorly explored.AimsA neurotropic murine coronavirus (mCoV) infection model was used to better characterize signals that promote fibroblast networks supporting accumulation of antiviral lymphocytes. Based on the early appearance of IgD+ B cells with unknown functions during several CNS infections,we probed their potential to activate stromal cells through lymphotoxin β (LTβ),a molecule critical in maintaining fibroblast-networks in lymphoid tissues as well as promoting TLS in autoimmunity and cancers.ResultsKinetic analysis of stromal cell activation in olfactory bulbs and brains revealed that upregulation of adhesion molecules and lymphoid chemokines Ccl19,Ccl21 and Cxcl13 closely tracked viral replication. Immunohistochemistry revealed that upregulation of the fibroblast marker podoplanin (PDPN) at meningeal and perivascular sites mirrored kinetics of RNA expression. Moreover,both B cells and T cells colocalized to areas of PDPN reactivity,supporting a potential role in regulating stromal cell activation. However,specific depletion of LTβ from B cells using Mb1-creERT2 x Ltβfl/fl mice had no effect on T or B cell recruitment or viral replication. B cell depletion by anti-CD20 antibody also had no adverse effects. Surprisingly,LTβR agonism reduced viral control and parenchymal T cell localization despite increasing stromal cell lymphoid chemokines and PDPN. Additional assessment of direct stromal cell activation by the viral RNA mimic poly I:C showed induction of Pdpn and Ccl19 preceding Ltb.ConclusionsNeither B cell-derived LTβ or B cells are primary drivers of stromal cell activation networks in the CNS following mCoV infection. Although supplementary agonist mediated LTβR engagement confirmed a role for LTβ in enhancing PDPN and lymphoid chemokine expression,it impeded T cell migration to the CNS parenchyma and viral control. Our data overall indicate that stromal cells can integrate LTβR signals to tune their activation,but that LTβ is not necessarily essential and can even dysregulate protective antiviral T cell functions.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12974-025-03491-7. View Publication

AbstractBackgroundWhile recent clinical trials of combination immunotherapies for hepatocellular carcinoma (HCC) have shown promising clinical efficacy and survival improvements breakthroughs,there is still much room for further improvement. A key limiting factor for HCC immunotherapy is the intrinsic immunosuppression within the liver microenvironment,resulting in suboptimal priming of tumor-specific CD8 cytotoxic T cells and thus immune evasion by the tumor. Hence,identifying new key molecular pathways suppressing T-cell responses within the liver is critical for the rational design of more effective combination immunotherapies for HCC.MethodsWe identified the 5-HT2A serotonin receptor as a potential target for HCC immunotherapy in a chemical screening approach and validated that targeting 5-HT2A signaling could be a viable approach for HCC immunotherapy via in vitro and in vivo studies.ResultsDisruption of 5-HT2A signaling using either a selective antagonist small molecule,ketanserin,or by knockout of its coding gene Htr2a augments the cytotoxic effector phenotype of mouse CD8 T cells activated in vitro with immunosuppressive liver non-parenchymal cells. Ketanserin treatment of in vitro activated human CD8 T cells also increased expression of the cytotoxic effector molecules granzyme B and perforin. Abrogation of 5-HT2A signaling was associated with increased expression of cytotoxicity-related genes such as granzyme B and reduced expression of transcription factors downstream of MAP kinase signaling. In vivo,systemic ketanserin treatment significantly prolonged survival of HCC tumor-bearing mice and was non-inferior to α-programmed death ligand 1 (PD-L1)+α-vascular endothelial growth factor A (VEGFA) combination antibody treatment. Combining ketanserin with αPD-L1+αVEGFA antibodies also significantly prolonged survival relative to control-treated mice while preserving the occurrence of complete tumor regression observed with αPD-L1+αVEGFA treatment alone.ConclusionsTogether,our data describe a role for 5-HT2A as a negative regulator of the cytotoxic effector phenotype in CD8 T cells and highlight the therapeutic potential of targeting 5-HT2A for HCC immunotherapy. View Publication

Post-transplant complications reduce allograft and recipient survival. Current approaches for detecting allograft injury non-invasively are limited and do not differentiate between cellular mechanisms. Here,we monitor cellular damages after liver transplants from cell-free DNA (cfDNA) fragments released from dying cells into the circulation. We analyzed 130 blood samples collected from 44 patients at different time points after transplant. Sequence-based methylation of cfDNA fragments were mapped to an atlas of cell-type-specific DNA methylation patterns derived from 476 methylomes of purified cells. For liver cell types,DNA methylation patterns and multi-omic data integration show distinct enrichment in open chromatin and functionally important regulatory regions. We find that multi-tissue cellular damages post-transplant recover in patients without allograft injury during the first post-operative week. However,sustained elevation of hepatocyte and biliary epithelial cfDNA within the first month indicates early-onset allograft injury. Further,cfDNA composition differentiates amongst causes of allograft injury indicating the potential for non-invasive monitoring and intervention. Current approaches to detect allograft damages non-invasively are limited and do not differentiate between cellular mechanisms. Here,the authors show that the composition of cell-free DNA in blood samples can reveal cellular causes of allograft injury after liver transplant. View Publication

SummaryStudying the cis-regulatory elements (CREs) of genes in Th17 cells during autoimmune disease progression,such as experimental autoimmune encephalomyelitis (EAE),is often limited by the availability of gene-edited mice. Here,we present a protocol for CRISPR-mediated deletion of a CRE in murine Th17 cells for in vivo assessment of effector function in EAE. We describe steps for dual U6gRNA construction,preparation of retroviruses,viral delivery,and Th17 differentiation. We then detail procedures for in vivo functionality analysis.For complete details on the use and execution of this protocol,please refer to Zhong et al.1,2 Graphical abstract Highlights•Steps for designing and cloning dual U6gRNA cassettes to delete a specific CRE•Instructions for optimized retrovirus production and transduction into CD4+ T cells•Guidance on Th17 differentiation and confirmation of CRE deletion in cultured T cells•Procedures for adoptive transfer of CRISPR-edited Th17 cells to assess in vivo function Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics. Studying the cis-regulatory elements (CREs) of genes in Th17 cells during autoimmune disease progression,such as experimental autoimmune encephalomyelitis (EAE),is often limited by the availability of gene-edited mice. Here,we present a protocol for CRISPR-mediated deletion of a CRE in murine Th17 cells for in vivo assessment of effector function in EAE. We describe steps for dual U6gRNA construction,preparation of retroviruses,viral delivery,and Th17 differentiation. We then detail procedures for in vivo functionality analysis. View Publication

BackgroundLevels of the human cationic antimicrobial host defence peptide LL-37 are enhanced in the lungs during neutrophilic airway inflammation. LL-37 drives Th17 differentiation,and Th17 cells produce IL-17A and IL-17F which form the biologically active heterodimer IL-17A/F. While IL-17 is a critical mediator of neutrophilic airway inflammation,LL-37 exhibits contradictory functions; LL-37 can both promote and mitigate neutrophil recruitment depending on the inflammatory milieu. The impact of LL-37 on IL-17-induced responses in the context of airway inflammation remains largely unknown. Therefore,we examined signaling intermediates and downstream responses mediated by the interplay of IL-17A/F and LL-37 in human bronchial epithelial cells (HBEC). As LL-37 can become citrullinated during airway inflammation,we also examined LL-37-mediated downstream responses compared to that with citrullinated LL-37 (citLL-37) in HBEC.ResultsUsing an aptamer-based proteomics approach,we identified proteins that are altered in response to IL-17A/F in HBEC. Proteins enhanced in response to IL-17A/F were primarily neutrophil chemoattractants,including chemokines and proteins associated with neutrophil migration such as lipocalin-2 (LCN-2). We showed that selective depletion of LCN-2 mitigates neutrophil migration,functionally demonstrating LCN-2 as a critical neutrophil chemoattractant. We further demonstrated that LL-37 and citLL-37 selectively suppress IL-17A/F-induced LCN-2 abundance in HBEC. Mechanistic studies revealed that LL-37 and citLL-37 suppresses IL-17 A/F-mediated enhancement of C/EBPβ,a transcription factor required for LCN-2 production. In contrast,LL-37 and citLL-37 enhance the abundance of ribonuclease Regnase-1,which is a negative regulator of IL-17 and LCN-2 in HBEC. In an animal model of allergen-challenged airway inflammation with elevated IL-17A/F and neutrophil elastase in the lungs,we demonstrated that CRAMP (mouse orthologue of LL-37) negatively correlates with LCN-2.ConclusionsOverall,our findings showed that LL-37 and citLL-37 can selectively suppress the abundance of IL-17A/F-mediated LCN-2,a protein that is critical for neutrophil migration in HBEC. These results suggest that LL-37,and its modified citrullinated form,have the potential to negatively regulate IL-17-mediated neutrophil migration during airway inflammation. To our knowledge,this is the first study to report that the immunomodulatory function of LL-37 enhances the RNA binding protein Regnase-1,suggesting that a post-transcriptional mechanism of action is mediated by the peptide.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12950-025-00446-w. View Publication

Metabolite nutrients within the tumor microenvironment shape both tumor progression and immune cell functionality. It remains elusive how the metabolic interaction between T cells and tumor cells results in different anti-cancer immunotherapeutic responses. Here,we use untargeted metabolomics to investigate the metabolic heterogeneity in patients with colorectal cancer (CRC). Our analysis reveals enhanced S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) metabolism in microsatellite stable (MSS) CRC,a subtype known for its resistance to immunotherapy. Functional studies reveal that SAM and SAH enhance the initial activation and effector functions of CD8+ T cells. Instead,cancer cells outcompete CD8+ T cells for SAM and SAH availability to impair T cell survival. In vivo,SAM supplementation promotes T cell proliferation and reduces exhaustion of the tumor-infiltrating CD8+ T cells,thus suppressing tumor growth in tumor-bearing mice. This study uncovers the metabolic crosstalk between T cells and tumor cells,which drives the development of tumors resistant to immunotherapy.Supplementary InformationThe online version contains supplementary material available at 10.1186/s40170-025-00394-2. View Publication

Various inhibitors targeting T-cell immunoglobulin and mucin-containing molecule 3 (TIM3) aimed at reversing T-cell exhaustion for better immunotherapy outcomes have demonstrated limited clinical efficacy as monotherapy,with the underlying mechanisms remaining ambiguous. TIM3 is markedly expressed in dendritic cells (DCs),and the inconsistent research findings on its role in myeloid cells underscore its vital function within DCs. Through the establishment of an in vitro differentiation model generating mature dendritic cells (mDCs) under TIM3-targeted interventions,combined with an RNA sequencing analysis,this investigation systematically examined TIM3-mediated regulation and ligand interactions in human primary DCs. The findings indicate that TIM3 inhibition hinders DC maturation,which subsequently diminishes the antigen-presenting capacity of DCs,ultimately leading to immune suppression in T cells. These findings collectively establish TIM3 as a regulator of DC differentiation that promotes DC maturation while optimizing the antigen-processing and presentation capacity. This study elucidates the rationale behind the suboptimal efficacy of TIM3 inhibitors and advocates for retaining TIM3 signaling pathways in DCs. View Publication

The prognosis for adult B-cell acute lymphoblastic leukemia remains unfavorable,especially in the context of relapsed and refractory disease. Exploring the molecular mechanisms underlying disease progression holds significant promise for improving clinical outcomes. In this investigation,utilizing single-cell transcriptome sequencing technology,we discerned a correlation between Ubiquitin-like containing PHD and RING finger domain 1 (UHRF1) and the progression of B-cell acute lymphoblastic leukemia. Our findings reveal a significant upregulation of UHRF1 in cases of relapsed and refractory B-cell acute lymphoblastic leukemia,thereby serving as a prognostic indicator for poor outcomes. Both deletion of UHRF1 or overexpression of its downstream target secreted frizzled-related protein 5 (SFRP5) resulted in the inhibition of leukemia cell proliferation,promoting cellular apoptosis and induction of cell cycle arrest. Our results showed that UHRF1 employs methylation modifications to repress the expression of SFRP5,consequently inducing the WNT5A-P38 MAPK-HK2 signaling axis,resulting in the augmentation of lactate,the critical metabolic product of aerobic glycolysis. Furthermore,we identified UM164 as a targeted inhibitor of UHRF1 that substantially inhibits P38 protein phosphorylation,downregulates HK2 expression,and reduces lactate production. UM164 also demonstrated antileukemic activity both in vitro and in vivo. In summary,our investigation revealed the molecular mechanisms of epigenetic and metabolic reprogramming in relapsed and refractory B-cell acute lymphoblastic leukemia and provides potential targeted therapeutic strategies to improve its inadequate prognosis. The schematic model showed the regulator network of UHRF1-SFRP5-WNT5A-P38 MAPK-HK2 in B-ALL. View Publication

Squalene-based emulsion (SE) adjuvants like MF59 and AS03 are used in protein subunit vaccines against influenza virus (e.g.,Fluad,Pandemrix,Arepanrix) and SARS-CoV-2 (e.g.,Covifenz,SKYCovione). We demonstrate the critical role of uric acid (UA),a damage-associated molecular pattern (DAMP),in triggering immunogenicity by SE adjuvants. In mice,SE adjuvants elevated DAMP levels in draining lymph nodes. Strikingly,inhibition of UA synthesis reduced vaccine-induced innate immunity,subsequently impairing optimal antibody and T cell responses. In vivo treatment with UA crystals elicited partial adjuvant effects. In vitro stimulation with UA crystals augmented the activation of dendritic cells (DCs) and B cells and altered multiple pathways in these cells,including inflammation and antigen presentation in DCs and cell proliferation in B cells. In an influenza vaccine model,UA contributed to protection against influenza viral infection. These results demonstrate the importance of DAMPs,specifically the versatile role of UA in the immunogenicity of SE adjuvants,by regulating DCs and B cells. View Publication

Extracellular DNA (eDNA) is crucial for the structural integrity of bacterial biofilms as they undergo transformation from B-DNA to Z-DNA as the biofilm matures. This transition to Z-DNA increases biofilm rigidity and prevents binding by canonical B-DNA-binding proteins,including nucleases. One of the primary defenses against bacterial infections are Neutrophil Extracellular Traps (NETs),wherein neutrophils release their own eDNA to trap and kill bacteria. Here we show that H-NS,a bacterial nucleoid associated protein (NAP) that is also released during biofilm development,is able to incapacitate NETs. Indeed,when exposed to human derived neutrophils,H-NS prevented the formation of NETs and lead to NET eDNA retraction in previously formed NETs. NETs that were exposed to H-NS also lost their ability to kill free-living bacteria which made H-NS an attractive therapeutic candidate for the control of NET-related human diseases. A model of H-NS release from biofilms and NET incapacitation is discussed. View Publication

Objective: Hypoxia–glycolysis–lactylation (HGL) may play a crucial role in neonatal sepsis (NS). This study aims to identify HGL marker genes in NS and explore immune microenvironment among NS subtypes. Materials and Methods: The gene expression dataset GSE69686,comprising 64 NS cases and 85 controls,was selected for analysis. Based on the screened HGL-related marker genes,diagnostic prediction models were constructed using nine machine learning algorithms,and molecular subtypes of NS were identified through consensus clustering. Subsequently,the heterogeneity of biological functions and immune cell infiltration among the different subtypes was analyzed. Finally,the marker genes and lactylation were validated using the GSE25504 dataset,clinical samples,and mouse neutrophil,respectively. Results: MERTK,HK3,PGK1,and STAT3 were identified and validated as marker genes,and the diagnostic prediction model for NS constructed using the support vector machine (SVM) algorithm exhibited optimal predictive performance. Based on gene expression patterns,two distinct NS subtypes were identified. Functional enrichment analysis highlighted significant immune-related pathways,while immune infiltration analysis revealed differences in neutrophil proportions between the subtypes. Furthermore,the expression levels of marker genes were positively correlated with neutrophil infiltration. Importantly,the experimental validation results were consistent with the findings from the bioinformatics analysis. Conclusion: This study identified the distinct NS subtypes and their associated marker genes. These findings will contribute to elucidating the disease's heterogeneity and establishing appropriate personalized therapeutic approaches. View Publication

Tumor-associated macrophages (TAMs) significantly influence tumor progression and patient responses to conventional chemotherapy. However,the interplay between anti-cancer drugs,immune responses in the tumor microenvironment,and their implications for cancer treatment remains poorly understood. This study investigates the effects of vinorelbine on M2 macrophages in lung cancer and its capacity to modulate TAMs toward an M1 phenotype. Peripheral blood mononuclear cells (PBMCs) were polarized into M2 macrophages,and subsequent phenotype alterations upon vinorelbine treatment were assessed. Additionally,we evaluated vinorelbine’s impact on gene and protein expression associated with cancer progression and cell invasion in non-small-cell lung cancer (NSCLC) cells indirectly co-cultured with M2 macrophages. Notably,vinorelbine,particularly at low concentrations,reprogrammed M2 macrophages to exhibit M1-like characteristics. While M2 macrophages enhanced cancer cell invasion,vinorelbine significantly mitigated this effect. M2 macrophages led to the overexpression of numerous genes linked to tumor growth,angiogenesis,invasion,and immune suppression in NSCLC cells,increasing the BCL2/BAX ratio and promoting cellular resistance to apoptosis. The anti-tumor efficacy of vinorelbine appears to be partly attributed to the reprogramming of M2 macrophages to the M1 phenotype,suggesting that low-dose vinorelbine may optimize therapeutic outcomes while minimizing toxicity in cancer patients. View Publication