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Kong, D.

Publications and source records attributed to Kong, D..

At least 19 recordsLinked to original sources

Spatially enforced engagement of PD-1⁺ T cells with AXL⁺ cells reprograms the tumor microenvironment and overcomes anti-PD-1 resistance

Background: AXL overexpression promotes tumor-cell plasticity, local immune suppression, and resistance to PD-1 blockade. Conventional anti-AXL and anti-PD-1 antibodies combinations act independently and do not ensure physical proximity between PD-1+ T cells and AXL+ cells within the immunosuppressive tumor microenvironment. Methods: To address this limitation, we developed a non-tandem, tetravalent IgG bispecific antibody designed to simultaneously engage PD-1 and AXL (BiTE-AXL/PD-1). Its antitumor activity was evaluated using in vitro functional assays and humanized and immunocompetent head and neck squamous cell carcinoma (HNSCC) models and compared with the combination of monospecific anti-AXL and anti-PD-1 antibodies. Spatial multiplex imaging was used to characterize treatment-associated changes in the tumor microenvironment of an anti-PD-1-resistant murine model. Results: BiTE-AXL/PD-1 enhanced T-cell activation, promoted AXL-dependent tumor-T-cell conjugation, and increased tumor-cell killing in vitro, outperforming the combination of the two monospecific antibodies. In humanized and immunocompetent HNSCC models, BiTE treatment significantly delayed tumor growth compared with the antibody combination and was well tolerated, with no overt toxicity. Spatial multiplex imaging revealed a shift from a fibroblast-dominated microenvironment characterized by exhausted CD8+ T cells toward dendritic-cell- and CD8+ T-cell-enriched niches associated with antitumor immune activity. Conclusion: BiTE-AXL/PD-1 promotes physical proximity between PD-1+ T cells and AXL+ cells, enhances antitumor immune responses, and remodels the immunosuppressive tumor microenvironment. These findings support PD-1/AXL bispecific targeting as a promising therapeutic strategy to overcome resistance to PD-1 blockade in HNSCC.

cancer biology↗

Liriodendrin Targets PFKFB3 to Suppress Inflammatory Phenotypic Transition and Vascular Remodeling in Pulmonary Hypertension

BackgroundPulmonary hypertension (PH) involves progressive vascular remodeling and perivascular inflammation. Despite modest clinical improvements with current therapies, their limited ability to reverse remodeling or restore immune homeostasis highlights the need for novel agents. Liriodendrin (Lidd), derived from Sargentodoxae caulis, exhibits anti-inflammatory and antiproliferative activities, but its efficacy and molecular targets in PH are unknown. MethodsTwo well-established PH animal models - the SU5416/hypoxia (SuHx) mice model and monocrotaline (MCT)-induced rat model - were employed for in vivo assessment of Lidd conducted pharmacological effects. Primary human pulmonary artery smooth muscle cells (hPASMCs) were utilized for mechanistic investigations. RNA-sequencing (RNA-seq) analysis was conducted to identify potential signaling pathways modulated by Lidd treatment. The direct molecular target of Lidd was determined through integrated application of drug affinity responsive target stability (DARTS) assay coupled with western blot validation. To delineate histone lactylation-mediated transcriptional regulation, we combined Cleavage Under Targets and Tagmentation (CUT&Tag) sequencing data analysis followed by chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) verification. Genetic validation was achieved using PFKFB3-deficient murine models to verify the specificity of Lidd-mediated pharmacological actions. ResultsLidd administration attenuated pulmonary vascular remodeling, perivascular macrophage infiltration and PH progression in both SuHx and MCT models. Transcriptomic profiling of Lidd-treated hPASMCs revealed predominant enrichment of downregulated genes in inflammatory and cytokine-associated pathways. Mechanistically, Lidd directly bound PFKFB3 and enhanced its interaction with FZR1, promoting PFKFB3 ubiquitination and degradation, which reduced glycolysis-driven lactate and consequent histone lactylation. This, in turn, diminished transcriptional activation of proliferative and inflammatory mediators, including CCND1, TNC, and CCL2. Notably, exogenous lactate supplementation or endogenous lactate accumulation restored histone lactylation and paradoxically potentiated Lidds inhibitory effects on PASMC proliferation and migration, whereas p300 inhibition abrogated these lactate-mediated effects. Importantly, Lidd failed to confer additional protection in PFKFB3-deficient mice, confirming PFKFB3 as the primary target mediating its therapeutic action. ConclusionOur findings reveal that Lidd selectively targets the PFKFB3-mediated glycolytic-epigenetic axis to suppress PASMC phenotypic transformation and pulmonary vascular remodeling, positioning it as a promising therapeutic candidate for PH.

physiology↗

PAIR-link: a ligation-free strategy that joins two RNAs into a single sequence-preserving chimeric cDNA

Physical proximity between RNA molecules, and between the proteins that bind them, underlies much of post-transcriptional regulation, yet the methods that convert these relationships into sequence do so at a cost. Established RNA-RNA interaction maps techniques depend on crosslinking, fragmentation, and/or proximity ligation, so each partner survives only as a short chimeric read in which full identity and sequence are not preserved. We describe PAIR-link (Priming Annealed Isothermal RNA linking), a ligation-free and fragmentation-free strategy that joins two separately transcribed RNAs into a single contiguous cDNA while retaining the sequence of both partners. Two engineered RNAs carry complementary tails at their 3 ends. These tails anneal and prime one another, and an isothermal Bst-family reverse transcriptase extends across the junction in both directions to copy both RNAs into one chimeric cDNA that can be amplified by PCR and read directly by Sanger sequencing. We first established the chemistry in vitro using synthesized oligonucleotides. Because the reaction requires a defined 3 end, we drove the barcode RNAs from RNA polymerase III promoters, whose transcripts terminate at a defined site, rather than from polyadenylated polymerase II transcripts. We then implemented PAIR-link in human cells as a reconstituted ribonucleoprotein in which each barcode RNA is tethered to one half of a split reporter protein (split-cpHaloTag or split-TurboID), so that reconstitution of the split protein brings the two RNAs together and facilitates linking. Bead-intact pull-down preserves the complex through reverse transcription and amplification. We recovered the expected sequence-verified chimeric product for reporters directed independently to the nucleus and to the cytoplasm, showing that the method operates across distinct subcellular environments. To our knowledge, PAIR-link is the first method to fuse two separately produced RNAs into a single chimeric cDNA molecule with full sequences of RNA preserved, without crosslinking, fragmentation, or ligation. We discuss the current scope of the approach, which is limited to RNAs with defined 3 ends, and outline routes toward future native transcripts and protein-interaction mapping.

molecular biology↗

Development of a Fully Non-Viral 1XX-enhanced BCMA CAR-T Cell Therapy for Multiple Myeloma

Multiple myeloma (MM) is a clonal plasma cell malignancy characterized by bone marrow infiltration, monoclonal immunoglobulin production, and microenvironmental dysregulation that leads to systemic organ damage. The advent of B-cell maturation antigen (BCMA)-directed chimeric antigen receptor (CAR) T-cell therapy has induced unprecedented responses and durability for patients with relapsed/refractory MM. These outcomes are rarely observed with prior salvage strategies, although relapse remains the predominant long-term challenge for most patients. The two currently approved BCMA CAR-T cell products use viral vectors to semi-randomly insert the CAR gene, which results in heterogeneous genomic composition and variability in efficacy, safety, and product consistency. To address these challenges, we integrated targeted CRISPR genome engineering with precise CAR transgene insertion at the T-cell receptor alpha constant (TRAC) locus, 1XX CAR signaling architecture to enhance potency and durability, and non-viral manufacturing with a single-stranded DNA repair template to improve efficiency and yield. This approach confers physiological CAR expression, reduces insertional mutagenesis, and improves persistence by mitigating tonic signaling and exhaustion. Our GMP manufacturing process consistently achieved high CAR integration (37.7-72.7%) and yields across all full-scale runs and met predefined release criteria for identity, purity, safety, and quality. In NSG mouse models of MM, the UCCT-BCMA-1 product exhibited exceptionally potent tumor control, CAR-T cell expansion 100-1000-fold greater than that of lentiviral constructs, and durable clearance of myeloma cells after multiple rechallenges. These findings establish a CRISPR-edited, fully non-viral manufacturing platform for next-generation 1XX-BCMA CAR-T therapies with enhanced persistence, safety, and efficacy. One Sentence SummaryCRISPR-engineered, TRAC-targeted 1XX-BCMA CAR-T therapy with improved safety, potency, and persistence in relapsed and refractory multiple myeloma.

cancer biology↗

Pan-cancer circular genomics identifies intratumoral Staphylococcus lugdunensis as a metabolic driver in bladder cancer

Intratumoral microbiota play key roles in cancer but are challenging to profile due to low biomass. We developed CIRCMIP, an enzymatic pipeline that eliminates linear DNA to enrich bacterial genomes, achieving 100-fold higher sensitivity than standard metagenomics. Applied to 312 pan-cancer specimens, CIRCMIP identified Staphylococcus lugdunensis as a signature bacterium enriched in early-stage bladder cancer (BLCA), where its presence predicts poor survival. Integrated modeling and lipidomics revealed that Staphylococcus lugdunensis colonization drives aberrant lipid metabolism with secretion of LPC14:0. Both Staphylococcus lugdunensis and LPC14:0 drive BLCA progression by promoting fatty acid uptake and {beta}-oxidation. Mechanistically, chemical proteomics revealed LPC14:0 as a direct PPAR{delta} ligand, binding via hydrogen bonds with Thr292/Thr289. This activation upregulates fatty acid transporters (CD36, FABP4) and metabolic enzymes (ACOX2), fueling malignant proliferation. Furthermore, CIRCMIP-derived biomarkers show robust diagnostic accuracy, establishing a new research paradigm and revealing the Staphylococcus lugdunensis-LPC14:0-PPAR{delta} axis as a therapeutic target in bladder cancer. HIGHLIGHTO_LICIRCMIP leverages DNA circularity to achieve 100-fold sensitivity in pan-cancer bacteriome profiling. C_LIO_LIStaphylococcus lugdunensis is a bacterial signature in early-stage bladder cancer that predicts poor patient survival. C_LIO_LIBacteria-derived LPC14:0 acts as a direct ligand for PPAR{delta} to drive host malignant metabolic reprogramming. C_LIO_LITargeting the Staphylococcus lugdunensis-LPC14:0-PPAR{delta} axis abrogates malignant progression in bladder cancer. C_LI

cancer biology↗

Identification of SNARE Genes in Cucumber and the Role of CsSYP121 in Salt Stress Response

Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are essential regulators of plant growth, development, and stress adaptation. In this study, we performed a comprehensive genome-wide identification of SNARE genes in cucumber (Cucumis sativus L.), uncovering 51 putative members designated as CsSNAREs. Phylogenetic analysis confirmed that these genes cluster into five major clades: Qa-CsSNARE (14), Qb-CsSNARE (9), Qc-CsSNARE (10), Qb+c-CsSNARE (3), and R-CsSNARE (15). Bioinformatic analysis of their promoter regions, coupled with expression profiling under diverse abiotic stress conditions, highlighted a heightened responsiveness within the Qa-CsSNARE subfamily. To validate this, we selected representative Qa-CsSNARE genes for quantitative real-time PCR analysis under drought and salt stress. Among these, CsSYP121 was notably induced by salt treatment. We subsequently generated transgenic cucumber lines overexpressing CsSYP121 and challenged them with salinity. Phenotypic assessment, combined with measurements of reactive oxygen species (ROS) accumulation and K+/Na+ ratios, demonstrated that CsSYP121 overexpression (OE) confers enhanced salt tolerance and boosts antioxidant capacity. We propose a model wherein CsSYP121 mitigates ROS-induced cellular damage under salt stress, potentially through promoting K+/Na+ homeostasis, thereby improving plant performance under saline conditions. Our findings identify CsSYP121 as a promising candidate gene for breeding salt-tolerant crops.

plant biology↗

Dingent: An Easily Deployable Database Retrieval and Integration Agent framework

AI-driven data search and integration represent an emerging research direction. Although several LLM-based backend frameworks and agentic frameworks have emerged, significant gap remains in developing a one-stop, configurable agent framework that supports various data sources and provides a web interface for efficient data retrieval using natural language. To address this, we present Dingent, a novel and configurable agent framework that facilitates data access from various resources and enables the flexible constructions of agent applications. We demonstrate its capabilities across three distinct application scenarios, achieving promising results. The Dingent framework can be readily applied to other fields, such as earth sciences and ecology, to facilitate data discovery.

bioinformatics↗

Persistent declines in forest-dependent birds following active restoration of logged tropical forest in Borneo

O_LITropical forest restoration is critical for mitigating biodiversity loss and climate change, including in forests impacted by selective logging. Active restoration through liana cutting and enrichment tree planting can substantially accelerate carbon recovery, potentially reducing economic pressures to convert logged forests. But its long-term biodiversity impacts remain largely unknown. C_LIO_LIUsing over two decades of bird survey data from Borneos largest logged-forest restoration project, we quantified occupancy patterns for 176 species across primary, naturally regenerating, and actively restored logged forests spanning a 30+ year post-logging chronosequence. C_LIO_LIForest-dependent, threatened and near-threatened species generally declined through time in actively restored areas, whereas many species in naturally regenerating forests progressively recovered toward primary forest levels. Between 17-40% of 66 threatened or near-threatened species had consistently lower occupancies in actively restored than in naturally regenerating forest. Across species of global conservation concern, median occupancies in restored areas remained [~]22% below primary forest even 50 years after harvests, compared with only [~]6% lower under natural regeneration. C_LIO_LIArboreal insectivores, frugivores, and predatory species appeared most negatively affected by active restoration, with 27-49% of arboreal gleaning insectivores (of 62), 13-30% of arboreal frugivores (of 40), and one-third of predatory species (of 15) showing higher occupancy in naturally regenerating forests. Sallying insectivores also showed a possible but uncertain response, whereas ground-associated frugivores and insectivores were largely unaffected by restoration treatment. C_LIO_LIConcerningly, even 50 years post-logging, up to 52% of 50 high forest-dependency species retained distinct occupancies in actively restored compared with primary forest, suggesting persistent negative impacts of vine-cutting and/or tree planting activities on avian populations. C_LIO_LISynthesis and applications. Our findings indicate that despite substantial carbon benefits, active restoration within selectively logged forests may impede the recovery of forest-dependent biodiversity. This challenges the common assumption embedded within nature-based climate solutions that carbon and biodiversity outcomes will necessarily align. Nonetheless, despite the persistent declines in bird communities, actively restored forests continued to provide key habitat for many species. Active interventions may thus still contribute to broader biodiversity conservation objectives if they protect logged areas from conversion, potentially via carbon payments. C_LI

ecology↗

Single-cell perturbations reveal adaptive, stimulus-dependent recurrence in visual cortex

Cortical circuits are proposed to amplify weak sensory inputs but transition to feature competition during strong drive. However, the evidence for this is scarce in cortices with a functional, modular organization, such as in primates and carnivores, where neighboring excitatory and inhibitory cells share feature selectivity. Here, we demonstrate that networks in ferret primary visual cortex switch between amplification and competition depending on sensory input. Combining cellular perturbations and statistical modeling, we uncovered broad suppressive influence modulated by visual contrast. At low contrast, functionally-coupled cells exhibited mutual amplification, switching to suppression at high contrast. This reversal emerged in recurrent network models in a Cross-Dominant regime, where inhibitory-excitatory coupling exceeds excitatory-excitatory coupling. These models predicted strong suppression from inhibitory cells, confirmed with cell-type-specific perturbations. Our results provide direct evidence that cortical recurrence with functional, modular organization toggles between amplification and suppression, supporting long-standing predictions from predictions from theory and models of visual cortex.

neuroscience↗

Ethylene receptors are functionally conserved in calcium permeability across the green lineage

The gaseous hormone ethylene plays a key role in regulating plant growth and stress responses. Although Ca{superscript 2} has long been implicated in ethylene signaling, the identity of molecules controlling Ca{superscript 2} permeability involved has remained elusive. Here we show that Arabidopsis ethylene receptors ETR1 and ERS1 are Ca2+ permeable, and that ETR1 mediates ethylene-induced cytosolic Ca2+ increase and regulates hypocotyl elongation. Homologs of ETR1 from eight land plant and algal species also exhibit Ca{superscript 2} permeability, suggesting an evolutionarily conserved function. We further demonstrate ethylene enhances the Ca2+ permeability of ETR1 and its homologue from the charophyte Klebsormidium flaccidum. These findings uncover a previously unrecognized but conserved role of ethylene receptors in Ca{superscript 2} permeability regulation in the green lineage, with broad implications for Ca{superscript 2} signaling in plant development and environmental adaptation.

plant biology↗

Rice Ethylene Receptors Function as Ca2+-Permeable Ion Channels to Orchestrate Calcium-Dependent Antagonism of Ethylene Responses in Roots

The gaseous phytohormone ethylene governs essential plant processes spanning development, productivity, and stress resistance. As an essential nutrient and second messenger, calcium (Ca2+) is widely implicated in diverse plant physiological activities; however, its role in the ethylene signal transduction pathway remains elusive. Here, we identified a calcium-dependent antagonism of ethylene response (CAER) specifically modulates root elongation in the model cereal rice (Oryza sativa). Interestingly, we demonstrate that the ethylene receptors OsERS1 and OsERS2 both function as Ca2+-permeable channels, with OsERS1 further acting as a non-selective cation channel capable of permeating both monovalent and divalent cations. Mutagenesis analysis reveals that OsERS1 channel activity relies on homomeric assembly sites (C4/C6) rather than its ethylene-binding site (C65), indicating a clear decoupling of the molecular modules governing receptor signaling and ion channel function. The loss-of-function mutant Osers1/2 does not exhibit the CAER phenotype of the wild type (WT), confirm that this calcium-dependent regulatory mechanism is dependent on both OsERS1 and OsERS2. These findings uncover an unexpected ion-channel function of ethylene receptors, redefining their molecular identity beyond canonical signaling proteins and establishing the novel "hormone receptor-type ion channel (HRIC)" paradigm--one that fundamentally expands our understanding of how plant hormones transduce signals at the membrane.

developmental biology↗

A Cross-scale Causal Mapping Framework Pinpoints Macrophage Orchestrators of Balanced Arterial Development

Postnatal pulmonary arteries experience an abrupt surge in flow that demands tightly coordinated remodeling of vascular structure and mechanical compliance. However, the cellular programs orchestrating these multiscale adaptation remain poorly defined, partly due to the absence of analytical tools integrating gene-cell-tissue scales. Here, we present CausaLink, a cross-scale causal mapping framework that predicts how altered gene expression propagates through gene-cell-tissue networks by integrating time-course transcriptomic and tissue morpho-mechanical data. We constructed a single-cell transcriptomic atlas of 11,143 proximal pulmonary artery-derived cells from C57BL/6J mice across five developmental stages (P2, P10, P21, P42, and P84), revealing dynamic lineage transitions and transient mesenchymal population specifying into fibroblasts and smooth muscle cells from P2 to P21. Using this framework, we identified Mgl2 macrophages as central regulators promoting lumen expansion while preventing pathological wall thinning or thickening. To validate these predictions, we established a human induced pluripotent stem cell-derived arterial assembloid enriched in MGLhigh macrophages. In this model, MGLhigh macrophages supported lumen enlargement while maintaining overall wall thickness and induced formation of an adventitia-like fibroblast layer that recapitulated approximately 80% of the native adventitial fraction with balanced collagen-elastin remodeling. By linking predictive modeling to human organoid validation, this study establishes a cross-scale workflow for tracing how gene programs shape vascular architecture, offering mechanistic insights and a foundation for predictive regenerative medicine.

bioengineering↗

PET-Microplastics Trigger Endothelial Glycocalyx Loss via ER Stress and ROS Unleashing IL-1β-Driven SMC Switching and Early Aortic Structural Impairment

Polyethylene terephthalate microplastics (PET-MPs), a major microplastics component identified in human vasculature, pose emerging environmental health risks. This study systemically profiled MPs in human aortic tissues and investigated the mechanisms underlying PET-MPs-induced aortic injury in vivo and in vitro. Chronic oral exposure of Sprague-Dawley rats to PET-MPs (1.0-100 mg/L) resulted in endothelial glycocalyx loss and structural impairment of aortic elastic fibers, with MPs accumulating within aortic endothelial cells. Transcriptomic and biochemical analyses revealed that PET-MPs triggered endoplasmic reticulum stress (ERS) and reactive oxygen species (ROS) generation in human aortic endothelial cells (HAECs), driving glycocalyx degradation and NF-{kappa}B-mediated inflammation. Proteomic profiling identified endothelial-derived IL-1{beta} as a key mediator, which subsequently induced phenotypic switching in human aortic smooth muscle cells (HASMCs) in vitro. Pharmacological inhibition of ERS (TUDCA), ROS (NAC), or IL-1{beta} (Canakinumab) attenuated this pathogenic cascade. Crucially, restoration of the glycocalyx using Sulodexide mitigated endothelial dysfunction and downstream HASMC phenotypic switching. These findings establish endothelial glycocalyx degradation via ERS-ROS as a novel mechanism for PET-MPs-induced vascular injury and highlight glycocalyx protection as a potential strategy against environmental microplastic hazards.

pharmacology and toxicology↗

OmniExtract: An automatic data extraction tool based on Large Language Model and Prompt Engineering

Extracting structured information from documents or scientific papers is crucial for data sharing and retrieval. Recently, Large Language Model (LLM) has shown its impressive ability in text understanding and several tools based on LLM has been developed. However, its still difficult to find a universal and user-friendly tool for various practical extraction tasks. To address this challenge, we propose OmniExtract, an automatic data extraction tool with user-friendly configuration files which can adapt to various data extraction tasks. OmniExtract uses a prompt optimized engineering to improve prompt and obtain high performance, and it can support a comprehensive data extraction including text and tables. Evaluation results show that OmniExtract obtains a high accuracy over 80% for 3 datasets. Furthermore, two additional data extraction applications using OmniExtract have been provided, achieving an accuracy of 92.21% and an average F1 score of 0.83 respectively. The data reliability performance shows that OmniExtract is a valuable tool for database updating.

bioinformatics↗

Spatial profiling of chromatin accessibility reveals alteration of glial cells in Alzheimer's disease mouse brain

Abnormal epigenetic modifications, including altered chromatin accessibility, have been implicated in the development and progression of Alzheimers disease (AD). In this study, we applied spatially resolved chromatin accessibility profiling by performing spatial assay for transposase-accessible chromatin using sequencing (ATAC-seq) to analyze brain tissues from 5xFAD AD model and C57BL/6J control mice. Our analysis identified seven major cell types across 11 brain regions and further characterized glial subtypes--microglia and astrocytes-- revealing subtype-specific chromatin accessibility changes in 5xFAD mice relative to controls. These alterations were associated with AD-related pathways, including neuroinflammation and immune dysregulation, and synaptic dysfunction and neuronal signaling in microglia, as well as lysosomal and proteasomal activity, lipoprotein metabolism, and mitochondrial dysfunction in astrocytes. We also characterized cell-type-specific enrichments of motifs and transcription factors, including enrichment of Bcl11a in microglia. Furthermore, we linked chromatin accessibility changes in 5xFAD mice to human AD risk genes, highlighting altered epigenetic signatures in genes such as Trem2. Supporting the spatial ATAC-seq findings, flow cytometry validated a selective increase in VISTA (encoded by Vsir) protein expression in 5xFAD microglia, supporting the spatial ATAC-seq findings and indicating a shift toward a pro-inflammatory, disease-associated microglial (DAM-like) phenotype. These findings underscore the utility of spatial chromatin accessibility profiling for uncovering brain-region specific cell identities and epigenetic mechanisms underlying AD pathogenesis.

bioinformatics↗

A rapid and efficient red-light-activated Cre recombinase system for genome engineering in mammalian cells and transgenic mice

The Cre-loxP recombination system enables precise genome engineering; however, existing photoactivatable Cre tools suffer from several limitations, including low DNA recombination efficiency, background activation, slow activation kinetics, and poor tissue penetration. Here, we present REDMAPCre, a red-light-controlled split-Cre system based on the {Delta}PhyA/FHY1 interaction. REDMAPCre enables rapid activation (1-second illumination) and achieves an 85-fold increase in recombination efficiency. We demonstrate its efficient regulation of DNA recombination in mammalian cells and mice, as well as its compatibility with other inducible recombinase systems for Boolean logic-gated DNA recombination. Using a single-vector adeno-associated virus (AAV) delivery system, we successfully induced REDMAPCre-mediated DNA recombination in mice. Furthermore, we generated a REDMAPCre transgenic mouse line and validated its efficient, light-dependent recombination across multiple organs. To explore its functional applications, REDMAPCre transgenic mice were crossed with the relative Cre-dependent reporter mice, enabling optogenetic induction of insulin resistance and hepatic lipid accumulation via Cre-dependent overexpression of ubiquitin-like with PHD and ring finger domains 1 (UHRF1), as well as targeted cell ablation through diphtheria toxin fragment A (DTA) expression. Collectively, REDMAPCre provides a powerful tool for achieving remote control of recombination and facilitating functional genetic studies in living systems.

synthetic biology↗

Generalization but not strengthening of negative memories drives the development of depression-like behaviors

Individuals with depression exhibit intensified and generalized negative memories. However, how prior memories actually influence onset and/or progression of depression, particularly whether the strengthening or the generalization of prior memories play a key role, is poorly understood. Here, we introduced behavioral paradigms to differentiate between memory strengthening and generalization, and found that negative experiences that produced memory overgeneralization, but not strengthening, induced depression-like behaviors. Furthermore, we identified that the medial prefrontal cortex (mPFC) to the bed nucleus of the stria terminals (BNST) projection functionally linked memory generalization to depression, together with single-cell calcium imaging which revealed a significant overlap in the mPFCBNST neuronal ensemble encoding depression-like behaviors with that encoding generalized memory, but not memory strength. Circuit-based transcriptomic analysis and chromophore-assisted light inactivation demonstrated that triggering actin remodeling in the mPFCBNST neurons, a memory consolidation mechanism enhanced generalization while reducing memory strength, also induced depression-like behaviors. Collectively, these findings suggest generalization of negative memories as a primary factor that drives depression-like behaviors, highlighting the importance of early identification of individuals at risk for depression who exhibit overgeneralized negative memories, and targeting overgeneralized negative memories in the treatment of depression.

animal behavior and cognition↗

Transplant immunosuppressant therapies induce unique functional changes in lymph node and re-shape gut immune homeostasis

BackgroundLifelong immunosuppressive therapy is required to prevent allograft rejection in organ transplantation. Current immunosuppressants effectively suppress adaptive and innate immune responses, but their broad, antigen-non-specific effects often result in severe off-target complications. It remains a significant unmet medical need in transplant medicine. ResultsIn this study we investigated immunosuppressant effects of four major immunosuppressant classes, including tacrolimus, prednisone, mycophenolate mofetil (MMF), and fingolimod (FTY), on the gut microbiome, metabolic pathways, lymphoid architecture and lymphocyte trafficking after up to 30-day chronic exposure. Despite their distinct mechanisms of action and not designed to target the gut, all immunosuppressive drugs induced profound and time-dependent alterations in both intestine gene expression and gut microbiome composition. Progressive alterations from moderate early, drug-specific changes to a strikingly convergent microbial dysbiosis, marked by significant expansion of pathobionts of Muribaculaceae, occurred across all drug classes. Concurrently, all drugs uniformly induced significant suppression of mucosal immunity including B cell, immunoglobulin, and antigen recognition. Time-dependent changes in lymph node (LN) reorganization and cellular composition were also observed, marked by a progressive shift toward pro-inflammatory phenotypes in gut-draining mesenteric LNs and a gradual loss of tolerogenic architecture in peripheral LNs. Drug-specific metabolic alterations and distinct phases of intestinal transcriptional responses were also characterized. Notably, MMF and FTY demonstrated the most robust immunomodulatory properties, and were able to suppress alloantigen-induced inflammation through mediating regulatory T cell distribution and LN remodeling. ConclusionsTogether, these findings highlight the underappreciated complexity and temporal dynamics immunosuppressants effects, particularly their impact on the gut and compartmentalized regulation of alloimmune in lymphoid tissues. Understanding these relationships offers new opportunities for refining immunosuppressive strategies to reduce treatment-related off-target complications and improve long-term organ transplant outcomes.

immunology↗