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Li, Y.

Publications and source records attributed to Li, Y..

At least 451 records · Page 25Linked to original sources

Nanobody MET CAR T cells show efficacy in solid tumors

BackgroundMET overexpression is associated with poor prognosis in many solid tumors due to its central role in tumor survival, invasion, metastasis, and chemoresistance. While targeting MET with antibody-drug conjugates has shown promising results, engineered cellular immunotherapeutic approaches have not been extensively explored. Compared to conventional single-chain variable fragments (scFv), naturally occurring single-domain antibodies consisting of variable heavy chains only (VHH or nanobodies) are smaller, retain high specificity, and exhibit remarkable biochemical stability. In this study, we tested the efficacy of MET-targeting VHH-CAR-T (chimeric antigen receptor T cells). MethodsWe generated a panel of VHH-CAR-Ts using mRNA electroporation. VHH-CAR-T cells were evaluated in functional assays including cell binding avidity, cytokine production profiles, hydrogel microwell-based cellular kinetics, and in vitro cytotoxicity. We also assessed the therapeutic efficacy of VHH-CAR-T in an in vivo mouse model of metastatic triple negative breast cancer (TNBC). ResultsAmong the tested VHH, we identified those with intermediate avidity as most effective for in vitro tumor killing. VHH-CAR-Ts with CD28 costimulatory domains demonstrated augmented cytotoxicity with favorable selectivity, requiring a minimum antigen density threshold for activation. Mechanistically, VHH-CAR-Ts demonstrated low tonic signaling, high avidity, potent cytokine production, and rapid tumor killing kinetics. When administered in an mRNA format, VHH-CAR-Ts exhibited potent and prolonged control of tumor growth in an in vivo metastatic model of TNBC. ConclusionTaken together, these results demonstrate that VHH-CAR-Ts exhibit robust MET specificity and potent therapeutic efficacy both in vitro and in vivo. Thus, VHH-CAR-T cell therapy represents a promising immunotherapeutic strategy for targeting MET-overexpressing solid tumors. What is already known on this topicMET signaling is an important contributor to the aggressiveness of many solid tumors, and targeting MET by antibody-drug conjugates has shown efficacy and safety. Targeting MET by CAR-T cells has been under study, though with limited potency. What this study addsThis study is the first to demonstrate effectiveness of anti-MET VHH-CAR-T cells. Compared with other antigen binding domains, VHH-incorporated CAR-T cells show low tonic signaling, a favorable cytokine profile, and potent tumor killing. How this study might affect research, practice or policyWith the multiple advantages of VHHs including small size, stability, and low potential for tonic signaling, VHH-CAR-T cells represent a promising approach for CAR-T design against solid tumors.

immunology↗

Endothelial MRG15 Is a Mechanosensitive Suppressor of Atherosclerosis

Disturbed blood flow induces early endothelial inflammation in atherosclerosis, yet the precise mechanisms of endothelial sensing of disturbed flow remain incompletely understood. In this study, we integrated proteomic profiling of human endothelial cells (ECs) subjected to disturbed flow with coronary artery disease risk related genes from large-scale genome-wide association studies (GWAS). We identified mortality factor 4-like protein 1 (MORF4L1, also called MRG15) as a critical modulator in the pathogenesis of atherosclerosis induced by disturbed flow. We show that the expression of MRG15 is markedly reduced in ECs of human aortic atherosclerotic plaques, as well as in ECs exposed to disturbed flow in mouse carotid artery and in cultured human umbilical vein endothelial cells (HUVECs). Endothelial-specific deletion of Mrg15 significantly worsened, while its overexpression attenuated endothelial inflammation and atherosclerotic lesions in turbulent blood flow- or Western diet-induced mouse atherosclerosis model. Single-cell transcriptomics showed that Mrg15 deficiency increased endothelial inflammation and intercellular adhesion molecule 1 (Icam1) expression, and enhanced integrin-mediated adhesion pathways. Mechanistically, MRG15 facilitated the recruitment of enhancer of zeste homolog 2 (EZH2) to maintain repressive histone H3 lysine 27 trimethylation (H3K27me3) marks on the promoters of ICAM1 and integrin subunit alpha 5 (ITGA5). Disturbed blood flow rapidly led to an elevation of protein neddylation, which subsequently induced neddylation-dependent degradation of MRG15 within endothelial cells. This degradation of MRG15 alleviated the transcriptional repression of ICAM1 and ITGA5, thereby enhancing monocyte adhesion to ECs. These findings highlight endothelial MRG15 as a mechanosensitive suppressor of atherosclerosis induced by disturbed flow. Consequently, MRG15 emerges as a promising novel therapeutic target for atherosclerosis.

molecular biology↗

FluNexus: a versatile web platform for antigenic prediction and visualization of influenza A viruses

Influenza A viruses continuously undergo antigenic evolution to escape host immunity induced by previous infections or vaccinations, consequently causing seasonal epidemics and occasional pandemics. Antigenic prediction and visualization of influenza A viruses are crucial for precise vaccine strain selection and robust pandemic preparedness. However, a user-friendly online platform for these capabilities remains notably absent, despite widespread demand. Here, we present FluNexus (https://flunexus.com), the first-of-its-kind, one-stop-shop web platform designed to facilitate the prediction and visualization of the antigenic change in emerging variants. FluNexus features a data preprocessing module for hemagglutinin subunit 1 (HA1) and hemagglutination inhibition (HI) data across three major public health threat subtypes (H1, H3 and H5). Meanwhile, FluNexus provides an interactive interface for online antigenic prediction and offers practical guidance for researchers. Most notably, FluNexus offers the visualization of influenza A virus antigenic evolution, providing intuitive insights into its antigenic dynamics. Specially, FluNexus proposes a novel manifold-based method for positioning antigens and antisera, generating accurate antigenic cartographies even with sparse HI data. By alleviating the programming burden on biologists, FluNexus supports more informed decision-making in vaccine strain selection and strengthens surveillance and pandemic preparedness. HighlightsO_LIFluNexus features a data preprocessing module for HA1 and HI data spanning the H1, H3, and H5 subtypes. C_LIO_LIFluNexus facilitates online antigenic prediction utilizing ten state-of-the-art antigenic prediction tools, and offers practical guidance based on a comparative evaluation of their performance. C_LIO_LIFluNexus provides a visualization module for mapping antigenic evolution of influenza A viruses, incorporating a novel manifold-based method for antigenic cartography. C_LI

bioinformatics↗

An Advanced Humanized Systemic Lupus Erythematosus Model Enables Parallel Profiling of B Cell-Targeted Therapies

B cell-targeted therapies represent a transformative frontier for systemic lupus erythematosus (SLE) intervention, yet clinical recommendation of specific treatment is hampered by the challenge to perform head-to-head comparisons of efficacy-toxicity trade-offs and tissue-specific impacts in patients. To address this gap, an advanced Toll-like receptor 7 (TLR7) agonist-induced SLE model is developed in a NCG-M (NOD-Prkdcem26Cd52Il2rgem26Cd22Rosa26em1Cin(hCSF2&IL3&KITLG)/Gpt) human immune system (HIS) mice. This model enables parallel evaluation of multiple B cell-directed therapies within a controlled cohort study. It recapitulates core SLE pathologies--including immune effector cell augmentation, autoantibody production and glomerulonephritis--within 2 months, demonstrating greater severity and clinical fidelity than conventional pristane-induced systems. Validated through replication of clinical responses to rituximab and belimumab, the platform directly compares two emerging modalities: universal chimeric antigen receptor-T cells (UCAR-T) elicits delayed but profound B-cell reset correlating with superior reduction in renal pathology and autoantibodies, while T cell engagers (TCEs) mediate rapid yet partial B-cell depletion and transient efficacy. UCAR-T concurrently induces greater acute inflammatory responses, aligning with its distinct toxicity profile. By resolving therapy-specific effects on human immune dynamics and symptom control, this study empowers context-specific therapeutic selection for SLE, advancing tailored management strategies.

immunology↗

Machine learning-based image analysis of Parkinson's disease iPS-derived neurons predicts genotype and reveals mitochondria-lysosome abnormalities

Mitochondrial and lysosomal dysfunction are central features of Parkinsons disease (PD) across major genetic forms including PRKN, SNCA, and LRRK2. We applied cell morphomics, a machine-learning-based framework combining high-content imaging with quantitative feature extraction, to analyse mitochondrial and lysosomal morphology at single-cell resolution in iPS cell-derived cortical neurons from PD patients and healthy controls (13 lines total). Supervised machine-learning models distinguished PD neurons from controls with high accuracy (AUC = 0.87) and reliably separated individual genotypes. Feature importance and attribution analysis revealed genotype-specific organelle biases, with mitochondrial features dominating classification in PRKN neurons, balanced mitochondrial and lysosomal contributions in SNCA neurons, and a greater lysosomal contribution in LRRK2 neurons. Multi-class models retained strong performance, and findings were reproduced across two independent laboratories using different dyes and imaging conditions. These results demonstrate that morphomics provides a robust and scalable framework to quantify genotype-specific organelle abnormalities in PD neurons and supports its application for cellular stratification and biomarker discovery.

neuroscience↗

Light-inducible proximity labelling in vivo captures sex-specific RNA at excitatory synapses

Local RNA regulation is essential for synaptic plasticity, yet the full repertoire of RNA species and associated isoforms within specific synaptic compartments in vivo has yet to be determined. Existing RNA profiling approaches lack the spatial and temporal precision needed to resolve RNA repertoires restricted to cell-type specific synaptic compartments. To overcome this challenge, we developed PSD-95-Halo-seq, a light-induced proximity labelling technique that, when combined with long-read sequencing, selectively captures all post-synaptic full length RNA species in the excitatory post-synaptic compartment. Here, we applied this approach to investigate sex differences in RNA expression within excitatory synapses following exposure to an associative fear learning task in C57/Bl6 mice. We found dramatic sex differences in pseudogene and protein coding RNA expression, which are most abundant in females, with males exhibiting multiple noncoding RNA classes, including lncRNA, snoRNA, and rRNA. Females generally showed more 3' UTR expression, and there was widespread differential exon usage following fear conditioning, including 179 isoforms in males, 69 in females, with no significant gene-level differential expression, indicating that behavioural state modifies sex-specific isoform usage rather than overall transcript abundance. Our discovery that synaptic RNA composition is dynamic, sexually dimorphic, and profoundly shaped by experience, offers new insight into previously inaccessible mechanisms underlying sex differences in fear-related learning and memory. PSD-95-Halo-seq is therefore a powerful method for the precise spatiotemporal identification of compartment-and cell-type-specific RNA. One sentence take-awaySynapse-targeted proximity labelling and Long-Read sequencing demonstrate that excitatory post-synapses encode experience through sex-specific, isoform-level RNA remodeling.

neuroscience↗

Spatial mapping of RNA turnover kinetics and regulatory landscapes of mRNA stability in the mammalian brain

Spatial and activity-dependent gene regulation in the mammalian brain requires coordinated control of RNA synthesis and degradation 1,2, yet spatially resolved measurement of RNA turnover kinetics in complex tissues remains technically challenging 3. Here, we present spatial NT-seq, an approach that integrates transgenesis-free metabolic RNA labeling with in situ chemical recoding to spatially co-map RNA abundance and turnover kinetics in the mouse brain. By distinguishing newly synthesized from pre-existing RNAs, this method reveals spatially resolved transcriptional and post-transcriptional responses to electroconvulsive stimulation (ECS), a treatment for refractory depression. We uncover pronounced spatial heterogeneity in RNA turnover, with the dentate gyrus (DG) exhibiting elevated basal RNA turnover and robust ECS-induced responses. These findings reveal a "kinetics scaling" mechanism of coordinated regulation of RNA synthesis and decay, by which DG cells can rapidly remodel their transcript pools in responses to external stimuli or differentiation signals 4,5. Machine learning applied to in vivo RNA kinetics landscapes further identifies sequence features and post-transcriptional regulators underlying region-and cell-type-specific control of mRNA stability. Together, this integrated experimental and computational framework, in vivo Timescope, enables transcriptome-wide mapping of RNA turnover kinetics and the regulatory architecture of RNA stability across spatial and cellular contexts, providing new insights into the spatiotemporal regulation of RNA dynamics in brain function and disease.

genomics↗

Fructose utilization by GM-CSF-differentiated macrophages aggravates autoimmune inflammation via MG-derived AGE-RAGE signaling

Excessive fructose intake is increasingly associated with metabolic and inflammatory pathologies; however, the direct impact of fructose metabolism on immune cell function remains insufficiently understood. Here, we demonstrate that GM-CSF-differentiated macrophages markedly upregulate the fructose-specific transporter GLUT5, enabling efficient fructose utilization through two complementary metabolic pathways. Using 13C-fructose tracing, we identified distinct carbon fluxes via a hexokinase (HK)-dependent glycolytic route and a ketohexokinase (KHK)-ALDOB-mediated fructolytic route. The HK-dependent pathway sustains glycolytic activity under glucose-limiting conditions, stabilizing HIF-1 and preserving pro-inflammatory gene expression. Conversely, the KHK-ALDOB axis increases dihydroxyacetone phosphate (DHAP) production, leading to methylglyoxal-derived advanced glycation end-products (MG-AGEs) that engage receptor for AGE (RAGE) signaling. This activation enhances MMP9 expression in macrophages and drives Th17 differentiation in CD4 T cells, amplifying inflammatory and tissue-remodeling processes. In vivo, fructose intake exacerbates autoimmune arthritis in SKG mice, and elevated fructose-driven glycolysis and MG-AGE accumulation are observed in monocytes from patients with rheumatoid arthritis. These results link fructose-driven carbonyl stress to macrophage effector programs and downstream T cell polarization. Collectively, these findings uncover a dual fructose metabolic program that integrates nutrient stress with persistent inflammation via the MG-AGE-RAGE axis and underscore the immunometabolic risks of excessive fructose exposure.

immunology↗

Leptin Receptor+ cells create a perisinusoidal niche for thrombopoiesis in the bone marrow by synthesizing CXCL14

Leptin Receptor-expressing (LepR+) stromal cells in the bone marrow are a critical source of growth factors for the maintenance of hematopoietic stem cells (HSCs) and most restricted hematopoietic progenitors. An important unresolved question is whether they also regulate terminal differentiation in some hematopoietic cells. We found that LepR+ cells promote thrombopoiesis by synthesizing the chemokine CXCL14, which is expressed in the bone marrow by a subset of LepR+ cells. Cxcl14-expressing LepR+ cells extend fine processes that wrap around perisinusoidal megakaryocytes. Deletion of Cxcl14 from LepR+ cells did not significantly alter HSC function or most aspects of bone marrow hematopoiesis, including megakaryocyte generation; however, it significantly reduced the numbers of proplatelet-forming megakaryocytes in the bone marrow and platelets in the blood. CXCL14 promoted platelet formation by remodeling lipid metabolism in megakaryocytes, increasing fatty acid transporter expression and enabling megakaryocytes to take up more polyunsaturated fatty acids from circulation. A high fat diet rescued the formation of proplatelet-forming megakaryocytes and platelets in Lepr-cre; Cxcl14 fl/fl mice. CXCL14 protein was sufficient to promote platelet formation by megakaryocytes in vitro and in vivo. LepR+ cells thus create a perisinusoidal niche for thrombopoiesis by producing CXCL14, which regulates lipid metabolism and terminal differentiation in megakaryocytes. Key pointsO_LILeptin Receptor+ stromal cells regulate terminal differentiation in megakaryocytes in addition to maintaining stem and progenitor cells C_LIO_LICXCL14 from Leptin Receptor+ cells promotes the formation of platelets by remodeling lipid metabolism in megakaryocytes in the bone marrow C_LI

cell biology↗

Radiosynthesis and Evaluation of Novel Cholesterol 24-Hydroxylase Positron Emission Tomography Tracers

Cholesterol 24-hydroxylase (CH24H or CYP46A1) is a pivotal enzyme in brain cholesterol metabolism and has emerged as a therapeutic and imaging target in neurodegenerative disorders. Although [18F]Cholestify ([18F]CHL-2205) has shown promise as a positron emission tomography (PET) tracer for imaging of CYP46A1, the impact of cyclopropyl moiety conformation on binding and imaging performance remains unexplored. Here, we report the rational design and preliminary evaluation of novel CYP46A1 PET tracers, in which the left-side cyclopropyl group was modified into bridged, spirocyclic, and fused bicyclic architectures to probe steric and conformational effects. All compounds 9-11 exhibited high CYP46A1 affinity (IC50 = 0.19-0.28 nM). Radiosynthesis of [18F]9-11 was achieved via copper-mediated [18F]fluorination, providing practical non-decay-corrected radiochemical yields of 10-34% with excellent radiochemical purity (>98%). In vitro autoradiography in rat brain sections demonstrated specific and regionally selective binding, comparable to that observed for [18F]CHL-2205. These cyclopropyl-derived scaffolds establish a scaffold-driven strategy for PET tracer development, providing a robust framework for further structure-activity relationship studies and the rational optimization of CYP46A1 PET tracers.

pharmacology and toxicology↗

S-nitrosylation of the CLIP-protease, Persephone, Regulates Drosophila innate immunity

Nitric oxide (NO) modulates innate immunity, but its molecular targets in Drosophila melanogaster are largely undefined. A key mechanism of NO signalling is S-nitrosylation, the modification of cysteine thiols. The homeostasis of S-nitrosylation is maintained by S-nitrosoglutathione reductase (Gsnor), encoded by the fdh gene in D. melanogaster. As reduced Gsnor activity enhances pathogen sensitivity in plants, we investigated its role in D. melanogaster. Here, we show that flies lacking fdh exhibit increased susceptibility to the fungus Beauveria bassiana and the bacterium Staphylococcus aureus, pathogens combatted by the Toll pathway. This immune deficiency correlates with impaired Toll-dependent antimicrobial peptide expression. We demonstrate that the Toll pathway protease Persephone (Psh) is S-nitrosylated in vivo and that loss of Gsnor prevents its proteolytic activation following infection. We propose a model where Gsnor-mediated regulation of NO is essential for Toll activation, preventing excessive S-nitrosylation of Psh and ensuring a robust immune response.

molecular biology↗

Epigenetic Programming of Macrophage Phenotypes by STING-IRF3 Drives Inflammation in Ascending Thoracic Aortic Dissection

BackgroundAscending thoracic aortic dissection (ATAD) is characterized by extensive macrophage (M{Phi}) accumulation and profound inflammation; however, the mechanisms sustaining pro-inflammatory M{Phi} activation remain incompletely defined. Emerging evidence indicates that epigenetically generated immune memory drives innate immune cells toward persistent inflammatory states. In this study, we investigated whether epigenetic reprogramming governs M{Phi} phenotypic fate and contributes to ATAD pathogenesis. MethodsWe performed single-cell RNA sequencing of human ascending aortic tissues from controls, patients with ascending thoracic aortic aneurysm (ATAA), and patients with acute ascending thoracic aortic dissection (ATAD). We also performed integrated single-cell RNA sequencing, single-cell ATAC sequencing, and spatial transcriptomics in an angiotensin II (Ang II)-infused mouse model. The role of the STING-IRF3 signaling axis in M{Phi} epigenetic programming was examined using M{Phi}-Sting -/- and M{Phi}-Irf3-/- mice. ResultsIn human and mouse aortic tissues, we identified multiple functional M{Phi} populations including pro-inflammatory, phagocytic/anti-inflammatory, proliferative, and reparative/healing M{Phi}s. Aortic M{Phi}s in both sporadic ATAD patients and Ang II-induced ATAD mice exhibited a pronounced pro-inflammatory bias with enhanced differentiation toward pro-inflammatory M{Phi}s and impaired differentiation toward phagocytic/anti-inflammatory states. Pro-inflammatory M{Phi}s were particularly abundant in dissection sites, whereas phagocytic M{Phi}s were enriched in discrete adventitial niches. Origin analyses revealed a substantial increase in CCR2 recruited M{Phi}s within the aortic wall, which preferentially differentiated into pro-inflammatory M{Phi}s. In contrast, LYVE1 resident M{Phi}s-- predominantly biased toward phagocytic phenotypes--were markedly depleted in ATAD. Single-cell ATAC sequencing identified coordinated chromatin remodeling with increased accessibility at pro-inflammatory gene loci and decreased accessibility at phagocytic gene loci. Among candidate transcriptional regulators identified, IRF family TFs, including IRF3 emerged as unique factors capable of simultaneously promoting pro-inflammatory gene programs while suppressing phagocytic gene expression. Mechanistically, STING-IRF3 signaling orchestrates this biased transcriptional state, likely through coordinated BRG1-dependent chromatin opening at pro-inflammatory gene loci and chromatin closing at phagocytic/anti-inflammatory gene loci. M{Phi} specific Sting -/- and Irf3-/- mice exhibited attenuated inflammatory reprogramming and reduced aortic destruction and dissection. ConclusionsThese findings identify STING-IRF3-mediated epigenetic programming of M{Phi}s as a fundamental mechanism driving aortic inflammation and ATAD development. Targeting M{Phi} epigenetic programming may represent a promising therapeutic strategy to prevent aortic dissection. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=189 HEIGHT=200 SRC="FIGDIR/small/701198v1_ufig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@c97bcdorg.highwire.dtl.DTLVardef@1df0ca8org.highwire.dtl.DTLVardef@b7fd04org.highwire.dtl.DTLVardef@1443e16_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Surf2Spot: A Surface-Informed Geometry-Aware Model for Predicting Binder and Nanobody Design Hotspots

Protein-protein interactions (PPIs) and nanobody-antigen interactions (NAIs) play essential roles in cellular function, yet accurate hotspot prediction remains challenging. We present Surf2Spot, a deep learning framework that integrates sequence embeddings, structural features, and protein surface properties to predict interaction hotspots. By jointly modeling structural and physicochemical determinants, Surf2Spot achieves superior performance on curated PPI and NAI datasets, improving F1-scores by 45.9-46.9% and AUPRC by 43.2% over existing methods. Case studies on NbPDS1 and VdPDA1 demonstrate that Surf2Spot accurately recovers experimentally validated hotspots clustered within functional domains. When incorporated into binder design pipelines (RFdiffusion and BindCraft), Surf2Spot-guided designs yielded a 4-fold increase in successful design throughput and enhanced binding affinities compared to baseline strategies. These results establish Surf2Spot as a powerful tool for hotspot discovery and rational protein engineering.

bioinformatics↗

Hepatocyte growth factor activator inhibitor-2 rapidly inactivates airway-expressed human Type II Transmembrane Serine Proteases

Human Type II Transmembrane Serine Proteases (TTSPs) are essential entry factors for various influenza A and coronaviruses, and drive cancer metastasis when they are overexpressed by tumor cells. However, the natural inhibition mechanisms that regulate these proteases are not well understood. One natural transmembrane protease inhibitor, hepatocyte growth factor activator inhibitor-2 (HAI-2), has been shown to block TMPRSS2 activity and can prevent SARS-CoV-2 infection and reduce TMPRSS2-driven prostate cancer metastasis when overexpressed. In this study, we present biochemical and biophysical evidence showing that HAI-2 effectively inactivates TMPRSS2 and other TTSPs only after they have undergone zymogen activation. Through mutagenesis and ligand binding assays, we demonstrate that Kunitz Domain 1 (KD1) and KD2 can form stable ternary complexes with TMPRSS2 and other TTSPs, but do not employ the typical Laskowski inhibitor mechanism found for other macromolecular serine protease inhibitors. We also show that HAI-2 proteins do not inhibit the coagulation protease thrombin and that multivalent human IgG-tagged HAI-2 proteins are highly potent TMPRSS2 inhibitors. Our findings provide a mechanistic understanding of how TTSP activity is regulated in human airway cells and offer a foundation for developing engineered soluble HAI-2 proteins as anti-TTSP antivirals and anti-cancer therapeutics.

biochemistry↗

Federated single-cell QTL meta-analysis reveals novel disease mechanisms

Genetic effects on gene expression are often cell type-specific and obscured in bulk analyses. To resolve this context-dependent regulation, we performed a federated cis-eQTL meta-analysis across 12 PBMC datasets (2,032 individuals, 2.5 million cells). Across six immune cell types, we identified cis-eQTLs for 6,592 genes and fine-mapped 14,985 independent loci. Notably, the 42% of eQTLs that were undetected in a bulk eQTL study on 43,301 whole blood samples also showed stronger enrichment for disease GWAS loci. We further identified three genome-wide significant and 65 suggestive loci affecting the abundance of (rare) immune cell types and validated these using previously reported hematological GWAS and bulk-derived trans-eQTLs. Integrating single-cell cis-eQTLs with bulk trans-eQTLs enabled us to anchor 6,382 trans-eGenes (37.2% novel) to upstream regulators and reconstruct directed gene regulatory relationships. For example, a hemorrhoidal disease-associated variant showed a CD4+ T cell-specific cis-eQTL on BACH1 that colocalized with 45 immune and metabolic trans-eGenes. These results demonstrate the power of single-cell QTL meta-analysis in interpreting complex trait genetics.

genetics↗

Direct evidence from kinetic D2O-MRI modeling that the choroid plexus is not the major source of cerebrospinal fluid

The role of the choroid plexus (CP) as the primary source of cerebrospinal fluid (CSF) remains controversial. Here, we used dynamic indirect D2O magnetic resonance imaging (MRI) at 9.4T to investigate whole-brain CSF dynamics in rats. Spin-echo echo-planar imaging (SE-EPI) was performed during intravenous D2O infusion with a temporal resolution of 10.69 s and an in-plane resolution of 150 x 150 {micro}m. An echo time of 150.0 ms was employed to effectively suppress signals from brain parenchyma, blood, and interstitial fluid, resulting in preferential visualization of CSF. The ambient and supracerebellar cisterns (AC+SC) exhibited the greatest signal attenuation, reaching 47.32 {+/-} 15.70% of baseline, whereas the lateral ventricles (LV1, LV2) showed smaller reductions (68.73 {+/-} 18.72%-72.64 {+/-} 15.07% of baseline). CSF production rates were quantified using a one-compartment perfusion model. Estimated secretion rates were 0.11 and 0.13 {micro}L/min in the lateral ventricles and 1.30 {micro}L/min in the AC+SC region, indicating a 5.42-fold higher CSF production outside the ventricles. These findings provide direct in vivo evidence that the lateral ventricles are not the primary site of CSF production. The proposed D2O-based dynamic SE-EPI approach is safe, non-invasive, cost-effective, and suitable for widespread application.

neuroscience↗

Lung-Targeting Interleukin-10 mRNA Lipid Nanoparticles Ameliorate Acute Lung Injury

Acute respiratory distress syndrome (ARDS) is the most severe manifestation of acute lung injury (ALI), characterized by diffuse pulmonary inflammation, impaired gas exchange, and high morbidity and mortality. Despite its clinical significance, no specific or effective pharmacological therapies are currently available for its treatment. In this study, we developed a lung -targeted mRNA-sulfonium lipid nanoparticle (mRNA/sLNP) delivery system for the treatment of ALI in a mouse model. We first optimized sulfonium lipid structures, and the optimized sLNP was comprehensively characterized and subsequently loaded with interleukin-10 (IL-10) mRNA. In a lipopolysaccharide (LPS)-induced ALI mousemodel, IL-10/sLNPdemonstrated both prophylactic and therapeutic efficacy, significantly attenuating pulmonary and systemic inflammation, restoring barrier integrity, and reducing tissue injury.

bioengineering↗

TLR7 inhibition limits cardiac ischemic injury by disrupting ITGAM-dependent immune-endothelial interaction

Percutaneous coronary intervention (PCI) limits ischemic myocardial infarction but also triggers ischemia-reperfusion (I/R) injury in part driven by innate immune activation. Here, we identify Toll-like receptor 7 (TLR7), an endosomal sensor of single-stranded RNA, as a mediator of post-ischemic inflammation and myocardial damage. Pharmacological inhibition of TLR7 with enpatoran reduced myocardial inflammation and infarct size and improved cardiac function in a mouse model of I/R injury when administered before, during, or shortly after ischemia. Single-nucleus RNA sequencing revealed coordinated post-I/R expansion of myeloid cells and distinct inflammatory endothelial subsets enriched for leukocyte-interaction programs, with marked upregulation of Itgam in cardiac leukocytes and endothelial cells and in circulating monocytes. Circulating ITGAM+ monocytes were similarly increased in patients with ST-segment elevation myocardial infarction 24 hours after coronary stenting. Mechanistically, TLR7 activation induced Itgam expression in endothelial cells and leukocytes and promoted their adhesion via ITGAM-ICAM1 interaction under physiological shear stress, whereas ITGAM neutralization disrupted this interaction, reduced immune cell infiltration, and limited ischemic injury. These findings define a TLR7-ITGAM signaling axis as a key driver of endothelial-leukocyte crosstalk in myocardial I/R injury and support TLR7 inhibition as a promising therapeutic strategy to mitigate acute myocardial infarction.

immunology↗