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Huang, J.

Publications and source records attributed to Huang, J..

At least 181 records · Page 10Linked to original sources

The Role of Chloride Ions in Serotonin Transport

The human serotonin (5-HT+) transporter SERT facilitates 5-HT+ transport into cells by coupling it to Na+ symport and K+ antiport. Although extracellular Cl- is also essential for transport, Cl-co-transport has been disputed, raising questions about the role of Cl- ions and why they are required. We show that Cl- gradients do not impact 5-HT+ accumulation, indicating that Cl- does not provide a driving force for uptake and arguing against stoichiometric Cl- symport. The presence of Cl- had only a small effect on Na+-mediated cytoplasmic pathway closure but markedly reduced the accessibility of residues in the extracellular pathway, consistent with modulation of the outward-facing states. Simulations illustrate that Cl- interacts strongly with a bound Na+ ion and stabilizes helix packing on the extracellular side. We propose that Cl- acts as an essential architectural cofactor by enhancing Na+ affinity and interactions between helices, thereby facilitating transport-related conformational transitions. Significance statementThe serotonin transporter (SERT) clears serotonin from synapses and is the target of widely used antidepressants. Although chloride ions are known to be required for SERT function, whether chloride is transported together with serotonin has remained unresolved for decades. We show that chloride gradients do not drive serotonin uptake, arguing against chloride symport. Instead, chloride stabilizes specific conformations of the transporter by strengthening sodium binding and extracellular helix packing. These findings redefine chloride not as a transported substrate, but as an architectural cofactor that facilitates conformational transitions required for transport. This reinterpretation reshapes our understanding of ion dependence in SERT and suggests a broader principle: ion requirements in related transporters may reflect structural stabilization rather than obligatory symport.

biochemistry↗

Immune activation of primary human macrophages is suppressed by the coordinated action of Yersinia effectors

In order to suppress the host immune response, numerous bacterial pathogens utilise a type 3 secretion system (T3SS) that injects effector proteins into host target cells. We investigated the T3SS effectors of Yersinia enterocolitica (Yops) for their individual and combined effects on gene expression, inflammasome formation and calcium signaling in primary human macrophages. YopP efficiently suppressed the up- and down-regulation of thousands of macrophage genes induced by the bacterias inflammatory stimuli. This was accompanied by parallel changes in histone 3-serine 10 phosphorylation, suggesting a higher-level regulatory mechanism. Surprisingly, YopM and YopQ counteracted selected YopP effects on gene expression, e.g., of cytokine pathways. A combination of YopP and YopQ, but not other combinations of Yops or any single Yop, reduced inflammasome formation. YopH alone blocked calcium transients in infected macrophages. We propose that the T3SS effectors of Yersinia antagonistically, synergistically or individually subdue major immune pathways of human macrophages to jointly suppress macrophage activation.

cell biology↗

Low-Strength Type I Interferon Signaling Promotes CAR T-Cell Treatment Efficacy

CD19-directed chimeric antigen receptor (CAR) T-cell therapy has significantly advanced the treatment landscape for relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL). However, up to 60% of patients do not achieve a complete response. To uncover determinants of therapeutic efficacy, we analyzed the infusion products of eight r/r DLBCL patients with distinct clinical responses to axicabtagene ciloleucel using single-cell transcriptomics. Compared to patients who exhibited progressive disease, infusion products of complete responders demonstrated enriched signatures of type I interferon (IFN-I) signaling. Based on these findings, we developed a novel strategy to improve CD19-directed CAR T-cell treatment efficacy by incorporating IFN-I as an enhancer during the ex vivo manufacturing process, with IFN-I removal before CAR T-cell infusion to avoid in vivo toxicities. For both CD28- and 4-1BB-costimulated second-generation CARs, we found that low-strength IFN-I signaling enhanced CAR T-cell cytotoxicity and treatment efficacy against B-cell lymphoma and leukemia. Our low-strength IFN-I-enhanced CAR T-cell ex vivo manufacturing approach leverages an existing FDA-approved pharmacologic agent, circumvents in vivo interferon-associated toxicities, and remains fully compatible with current CAR constructs and manufacturing workflows. Together, our results establish IFN-I as a potent and costimulation-independent enhancer of CAR T-cell efficacy and provide a translationally feasible approach to enhance CAR T-cell therapies.

immunology↗

Quantitative RNA pseudouridine landscape reveals dynamic modification patterns and evolutionary conservation across bacterial species

Pseudouridine ({Psi}) modifications are the most abundant RNA modifications; however, their distribution and functional significance in bacteria remain largely unexplored compared to eukaryotic systems. In this study, we present the first transcriptome-wide and quantitative mapping of {Psi} modifications across five diverse bacterial species (Bacillus cereus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Pseudomonas syringae) at single-base resolution, utilizing the optimized BID-seq method for bacterial RNA. Our analysis revealed growth phase-dependent dynamics of pseudouridylation in bacterial tRNA and mRNA, particularly in genes enriched in core metabolic pathways. Comparative analysis demonstrated evolutionarily conserved features of {Psi} modifications, such as dominant motif contexts, {Psi} clustering within operons, etc. Functional analysis indicated {Psi} modifications influence bacterial mRNA stability, translation, and interactions with specific RNA-binding proteins (RBPs) in response to changing cellular demands during growth phase transitions. The integrated computational analysis on local RNA architecture was conducted to elucidate the structure-dependent {Psi} modifications in bacterial RNA. Furthermore, we developed an integrated deep learning framework, combining Transformer-GNN-based neural networks (pseU_NN) to capture both RNA sequence and structural features for effective prediction of {Psi}-modified sites. Overall, our study provides valuable insights into the landscapes of bacterial RNA {Psi} modifications and establishes a foundation for future mechanistic investigations into the functions of {Psi} in bacterial RNA regulation.

microbiology↗

Monocyte single cell-type gene expression measured in peripheral blood by DIRECT LS-TA method: the ratio-based biomarkers of (IFI27/PSAP) showed superior performance than interferon score in triage patients with viral infection

A rapid method to triage febrile patients into different categories of etiologies remains a significant challenge even nowadays, when many molecular tests for pathogens are available. Routine serum protein tests like C-reactive protein and procalcitonin have limited specificity. Host response gene signatures are promising biomarkers but they usually require assaying many genes, e.g. 7 genes are commonly used to calculate the interferon (IFN) score. However, these gene panels fail to capture cell-type-specific host responses. Measuring gene expression of a specified single cell population, like monocytes, offers enhanced biological insight. However, it currently requires laborious cell sorting or costly single-cell sequencing techniques, limiting its clinical applicability. This study aims to develop a simple ratio-based biomarker (RBB) representing monocyte-specific host response to viral infection called DIRECT LS-TA method. A simple ratio of 2 genes (both are shortlist monocyte informative genes) quantified in peripheral blood (PB) samples correlated with gene expression in purified monocytes in the corresponding individual. These RBBs cover 3 interferon-stimulated genes (ISGs): IFI27/PSAP, IFI44L/PSAP and SIGLEC1/PSAP. They are compared to the conventional multi-gene IFN score in the differentiation of viral infection. Public gene expression datasets from NCBI GEO were used to shortlist monocyte-informative genes that can be used as the RBB in PB. The DIRECT LS-TA RBB was calculated as the ratio of the target ISG transcript abundance (TA) to that of another reference gene (PSAP or CTSS) directly quantified from bulk PB data (e.g., Log(IFI27/PSAP) in WB). The correlation (expressed by coefficient of determination, R{superscript 2}) between these DIRECT LS-TA RBBs and the gold-standard target gene TA measured in purified monocytes was assessed. The diagnostic performance of selected RBBs (IFI27/PSAP, IFI44L/PSAP, SIGLEC1/PSAP) was compared against the conventional 8-gene IFN score for differentiating viral infections from controls. Direct LS-TA RBBs measured in PB showed strong correlation with gold-standard gene expression measured in purified monocytes (R2 ranged from 0.53 for the target gene IFI27 to >0.9 for the target gene IFI44L). This high level of correlation supports that this simple RBB (DIRECT LS-TA) method can replace the tedious cell sorting approach to obtain single-cell-type gene expression data. All DIRECT LS-TA results of ISGs were raised during viral infection. The best clinical performance in triaging viral infection patients was achieved by IFI27/PSAP or IFI27/CTSS across all datasets. For example, in the GSE111368 dataset, IFI27/PSAP achieved an AUC of 0.94 (95% CI 0.90-0.97) with 88% sensitivity and 95% specificity, surpassing the IFN scores AUC of 0.90 (95% CI 0.85-0.94) with 79% sensitivity and 93% specificity. ConclusionThe DIRECT LS-TA method, utilizing the format of simple two-gene ratio-based biomarkers like IFI27/PSAP, provides a robust and accurate measure of monocyte-specific interferon pathway activation directly from peripheral blood. The superior performance of the DIRECT LS-TA method makes it a promising, readily implementable tool for clinical triage. Its ability to provide single-cell-type specific information, rapid turnaround using standard qPCR/dPCR technology, and enhanced biological specificity make it a valuable molecular host response assessment.

immunology↗

Characterization of the glycoproteins of novel fish influenza B-like viruses

Novel influenza-like virus sequences previously identified in fish and amphibians were found to cluster as a sister clade of influenza B viruses, but have thus far remained uncharacterized. We demonstrate that salamander influenza-like virus (SILV) HA is functionally divergent from influenza B virus HA and does not bind to 2,3- and 2,6-linked sialic acids. However, the HAs of Siamese algae-eater influenza-like virus (SAEILV) and chum salmon influenza-like virus (CSILV) bind to 2,3 linked sialic acid. Furthermore, SAEILV HA binds to sialyated Lewis X, is activated by human airway enzymes and is fusogenic at a wide range of pH conditions. SAEILV NA has a highly conserved active site and a similar structure to other known NAs. We also determined the cryo-electron microscopy structure of the HA of a previously described virus from the same sister clade, the Wuhan spiny eel influenza virus (WSEIV). Importantly, no cross-reactive antibodies against these HAs or NAs were found in the human serum, suggesting that humans are immunologically naive to these viruses. One sentence summaryNovel influenza like-viruses, displayed different target receptor specificity and limited antigenic conservation of the HA and NA relative to influenza B Viruses.

microbiology↗

Benchmarking Universal Machine Learning Force Fields with Hydrogen-Bonding Cooperativity

Machine learning force fields (MLFFs) offer a promising balance between quantum mechanical (QM) accuracy and molecular mechanics efficiency. While MLFFs have shown strong performance in modeling short-range interactions and reproducing potential energy surfaces, their ability to capture long-range cooperative effects remains underexplored. In this study, we assess the ability of three MLFF models -- ANI, MACE-OFF, and Orb -- to reproduce cooperative interactions arising from environmental induction and dispersion, which are essential for many biomolecular processes. Using a recently proposed framework, we quantify hydrogen bond (H-bond) cooperativity in N-methylacetamide polymers. Our results show that all MLFFs capture cooperativity to some extent, with MACE-OFF yielding the closest agreement with QM data. These findings highlight the importance of evaluating many-body effects in MLFFs and suggest that H-bond cooperativity can serve as a useful benchmark for improving their physical fidelity.

biophysics↗

Molecular and Epigenetic Pathways Underlying Epithelial Damage and Repair in Necrotizing Enterocolitis via Multi-omics Approach

IntroductionNeonatal necrotizing enterocolitis (NEC) is a severe gastrointestinal disorder with high mortality, characterized by epithelial cell injury and compromised epithelial repair. The mechanisms underlying defective epithelial regeneration remain poorly understood despite advances in single-cell omics. Addressing these challenges is essential for elucidating the pathogenesis of NEC and identifying therapeutic targets to restore epithelial regeneration and replace the damaged epithelial layer. MethodsMulti-omics approaches were employed to investigate molecular and spatial changes in experimental NEC at epigenetic and transcriptomic levels. These included bulk RNA sequencing, single-nucleus RNA sequencing (snRNA-seq), single-nucleus assay for transposase-accessible chromatin sequencing (snATAC-seq), and multiplexed error-robust fluorescence in situ hybridization (MERFISH) for spatial transcriptomics. Complementary in vitro experiments and in vivo mouse models were utilized to evaluate NEC phenotypes, intestinal tissue morphology, and organoid formation. ResultsChanges in cell type composition, transcriptional network remodeling, and chromatin accessibility were observed in the small intestine of neonatal mice with NEC. Chromatin accessibility significantly changed in epithelial cells, highlighting their pivotal roles in NEC. A marked reduction in intestinal stem cells (ISCs) and transit-amplifying cells, along with an increased proportion of enteroendocrine cells, indicates disrupted epithelial regeneration and functional differentiation. These changes correlated with disrupted WNT signaling and stem cell maintenance genes (e.g., Lgr5, Smoc2, Axin2) and activation of inflammatory and hypoxia-related pathways (e.g., Il6, Tnf). The epigenetic regulator Ezh2 was identified as a critical factor in maintaining LGR5+ ISCs and epithelial homeostasis. Knockdown of Ezh2 reduced stemness and proliferation-related gene expression and exacerbated inflammation. Reactivation of WNT signaling restored Ezh2 and Lgr5 expression, improving intestinal regeneration. ConclusionThis study reveals dynamic transcriptomic, epigenetic, and spatial changes in NEC and highlights Ezh2 as a key regulator of LGR5+ intestinal stem cell function and epithelial regeneration. These findings provide insights into NEC pathogenesis and a basis for therapies targeting Ezh2 and WNT signaling to restore intestinal integrity. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=194 SRC="FIGDIR/small/647851v1_ufig1.gif" ALT="Figure 1"> View larger version (53K): org.highwire.dtl.DTLVardef@1ad89eaorg.highwire.dtl.DTLVardef@396282org.highwire.dtl.DTLVardef@172596forg.highwire.dtl.DTLVardef@4daf28_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

Distinct Bomanins at the Drosophila 55C locus function in resistance and resilience to infections

Host defense against many Gram-positive bacteria and fungal pathogens is mainly provided by the Toll-dependent systemic immune response in Drosophila. While antimicrobial peptides active against these categories of pathogens contribute only modestly to protection, Bomanin peptides are major effectors of the Toll pathway. Remarkably, flies deleted for the 55C locus that contains 10 Bomanin genes are as sensitive as Toll pathway mutant flies to these infections. Yet, the exact functions of single Bomanins in resistance or resilience to infections remain poorly characterized. Here, we have extensively studied the role of these Bomanin genes. BomT1 functions in resistance to Enterococcus faecalis while playing a role in resilience against Metarhizium robertsii infection, like BomS2. BomT1 and BomT2 prevent the dissemination of Candida albicans throughout the host, even though they are not sufficient to confer protection to immunodeficient flies against this pathogen in survival experiments. Furthermore, BomT1 and BomBc1 mutants are sensitive to an Aspergillus fumigatus ribotoxin. We conclude that 55C Bomanins have defined albeit sometimes overlapping roles in the different facets of host defense against infections.

immunology↗

Breaking the Link: Neural Dissociation of Attention and Working Memory through Inhibitory Control

Attention and working memory (WM) encoding have traditionally been considered inseparable processes with shared neural mechanisms. Here, using an innovative experimental design and a multimodal approach, we provide the first direct neural evidence that attention and WM encoding are dissociable. Functional MRI identifies the supramarginal gyrus (SMG) as the key region enabling this dissociation, while dynamic causal modeling reveals the neural circuitry through which the SMG exerts inhibitory control over attentional representations, regulating their integration into WM. Furthermore, neuromodulation via transcranial direct current stimulation (tDCS) demonstrates that enhancing SMG activity strengthens this inhibitory control, providing causal evidence for the dissociation mechanism. A second tDCS experiment with varied stimuli confirms the generalizability of this mechanism and reinforces the robustness of our results. These findings challenge the long-standing view that attention and WM encoding form a continuous process, demonstrating instead that they constitute two dissociable neural processes of information selection.

neuroscience↗

Cryopreservation of Human Cortical Organoids Using Vitrification.

Cryopreservation at ultra-low temperatures is a valuable tool for preserving cells and tissues used in research. However, few protocols exist for the preservation of brain organoid models. Current methods for preserving human cortical organoids (hCOs) rely on conventional slow cooling approaches with organoids suspended in a medium containing a cocktail of cryoprotectants. In contrast, we have optimized a vitrification technique previously used to cryopreserve human embryos and oocytes for application to hCOs. We have successfully cryopreserved hCOs that were generated by two different protocols. The vitrified organoids demonstrate a growth rate, cytoarchitecture, cell type composition and electrical activity comparable to non-vitrified controls. Our hCO cryopreservation method provides a useful alternative approach for bio-banking and cross-institutional collaboration using cortical organoids as their model system. Highlights- Human pluripotent stem cell (hPSC) derived hCOs can be cryopreserved using vitrification. - Vitrified hCOs develop similarly to non-vitrified controls. - Vitrified hCOs can be stored long-term and shipped to other institutions. MotivationMany methods of cryopreservation have been developed for the maintenance of cell lines, organoid models and tissues. Most organoid models have been successfully preserved using conventional slow-cooling methods; however, human cortical organoids have been difficult to preserve. Our findings demonstrate that the vitrification of cortical organoids preserves their structure, cell type diversity and function upon rewarming and continued culture.

neuroscience↗

An unrecognized and crucial role of chloroplast division in leaf variegation in Arabidopsis thaliana

Leaf variegation provides a valuable model for elucidating the molecular mechanisms that underlie chloroplast biogenesis, including both chloroplast development and division. While there has been notable advancement in comprehending the role of the Arabidopsis Yellow Variegated2 (VAR2), which encodes the AtFtsH2 subunit of the thylakoid FtsH metalloprotease complex, the exact mechanism governing leaf variegation formation remains elusive. In this study, time-course microscopy analyses of chloroplast number per cell from the first leaf pair revealed that most var2 cells lack chloroplasts. Interestingly, chloroplast biogenesis in the green sector of var2 leaves is significantly delayed but prolonged compared to the wild type (WT), leading to increased heterogeneity in chloroplast number and size among cells. These results suggest that chloroplast biogenesis in the green sector can partially compensate for the defect in the white sector. Additionally, approximately 15% of cells in var2 white sectors are devoid of plastids, and chloroplast number in guard cells is significantly lower in var2 than in WT, indicating that VAR2 mutations impair chloroplast division. Consistently, the var2 phenotype is exacerbated by knocking out key plastid division genes, including Paralog of Accumulation and Replication of Chloroplasts6 (PARC6) and Plastid Division1 (PDV1), but is fully rescued by overexpressing PDV1 or PDV2. Furthermore, VAR2 mutations inhibit etioplast development, while accelerating chloroplast biogenesis by knocking out Constitutively Photomorphogenic1 (COP1) rescues the var2 phenotype. Together, our findings reveal a novel role for VAR2 in plastid division and its essential function in chloroplast biogenesis, providing new insights into the mechanism underlying variegated leaf formation.

plant biology↗

Spatial transcriptomics AI agent charts hPSC-pancreas maturation in vivo

Spatial transcriptomics has revolutionized our understanding of tissue organization by simultaneously capturing gene expression and spatial localization within intact tissues. However, analyzing these increasingly complex datasets requires specialized expertise across computational biology, statistics, and biological context. To address this challenge, we introduce the Spatial Transcriptomics AI Agent (STAgent), an autonomous multimodal agentic AI that integrates multimodal large language models (LLMs) with specialized computational tools to transform weeks-long analysis tasks into minutes of automated processing. Unlike conventional machine learning approaches that are limited to narrow, predefined tasks, STAgent leverages the emergent capabilities of multimodal LLMs - such as flexible reasoning, contextual understanding, and cross-modal integration - which allow it to adapt to novel data, execute multi-step analyses, and generate biologically meaningful insights with minimal human input. STAgent enables autonomous deep research through integrated capabilities, including dynamic code generation for complex analytical workflows, visual reasoning for interpreting spatial patterns, real-time retrieval of relevant peer-reviewd scientific literature, and synthesis of comprehensive, actionable reports. We applied STAgent to investigate the in vivo maturation of human stem cell-derived pancreatic cells (SC-pancreas) transplanted into immunodeficient mice. We generated single-cell spatial transcriptomics data spanning multiple developmental timepoints. STAgent autonomously (1) identified the maturation of initially scattered endocrine cells into well-defined islet-like structures, with predominantly peripheral -cells surrounding {beta}-cell cores supported by an expanding mesenchymal network; (2) revealed strengthening endocrine-endocrine cell interactions over time and, through context-aware gene set analysis, uncovered spatially resolved biological processes driving maturation; (3) unlike traditional analytical approaches, STAgent offers mechanistic explanations of spatial patterns, contextualizing findings with relevant literatures and developing cohesive insights into human pancreatic development. This agentic approach establishes a new paradigm in spatial transcriptomics analysis by substantially lowering the expertise barrier and reducing analysis time, accelerating biological and biomedical discovery.

genomics↗

Gangliosides Modulate the Secretion of Extracellular Vesicles and Their Misfolded Protein Cargo

Gangliosides are glycosphingolipids that play an integral role in cell signaling and provide neuroprotection. While present on extracellular vesicles (EVs) - key mediators of intercellular communication - their role in EV biogenesis remains unclear. Here, we identify gangliosides, both endogenously synthesized and exogenously administered, as key modulators of EV biogenesis, with the specific composition of their glycan headgroup and the presence or absence of sialic acid and N-acetyl-D-galactosamine residues dictating whether they promote or inhibit EV biogenesis. We show that GM1 and other complex gangliosides enhance EV secretion, while disruption of ganglioside synthesis impairs it. GM1 supplementation restores EV secretion in Huntingtons disease (HD) fibroblasts and HD cell models that have lower than normal levels of gangliosides, and in cells with a genetic block of ganglioside synthesis that models rare early-onset neurodegenerative diseases. Notably, GM1 also enhances EV-mediated secretion of pathogenic misfolded proteins, including mutant huntingtin (mHTT), -synuclein and tau, reducing intracellular burden and providing mechanistic insight into the mHTT-lowering effects of GM1 treatments in HD models. Our findings shed light on the neuroprotective roles of gangliosides and highlight their potential for therapeutic exploitation in misfolded protein disorders.

cell biology↗

Quantifying the Cooperativity of Backbone Hydrogen Bonding

The hydrogen bonds (H-bonds) between backbone amide and carbonyl groups are fundamental to the stability, structure, and dynamics of proteins. A key feature of such hydrogen bonding interactions is that multiple H-bonds can enhance each other when aligned, as such in the -helix or {beta} -sheet secondary structures. To better understand this cooperative effect, we propose a new physical quantity to evaluate the cooperativity of intermolecular interactions. Using H-bond aligned N-methylacetamide molecules as the model system, we assess the cooperativity of protein backbone hydrogen bonds using quantum chemistry (QM) calculations at the MP2/aug-cc-pVTZ level, revealing cooperative energies ranging from 2 to 4.3 kcal/mol. A set of protein force fields was benchmarked against QM results. While the additive force field yielded null cooperativity, polarizable force fields, including the Drude and AMOEBA protein force fields, have been found to reproduce the trend of QM results, albeit with smaller magnitude. This work demonstrates the theoretical utility of the proposed formula for quantifying cooperativity and its relevance in force field parameterization. Incorporating cooperative energy into polarizable models presents a pathway to achieving more accurate simulations of biomolecular systems.

biophysics↗

Allo-PED: Leveraging protein language models and structure features for allosteric site prediction

Allosteric regulation plays a pivotal role in modulating protein function and allosteric sites represent a promising target for drug discovery. However, identifying allosteric sites remains challenging due to their structural and evolutionary diversity. Here, we present AlloPED, a novel framework that combines protein language models and machine learning to predict allosteric sites with high accuracy. AlloPED consists of two modules: AlloPED-pocket, an ensemble model leveraging physicochemical features to predict allosteric pockets; and AlloPED-site, a dilated convolutional neural network (DCNN) augmented with a comprehensive attention mechanism for residue-level prediction. AlloPED-pocket achieves state-of-the-art performance on benchmark datasets, yielding an MCC of 0.544 and an AUC of 0.920, outperforming existing methods such as AllositePro and PARS. AlloPED-site further refines predictions using high-dimensional sequence embeddings from the ProtT5 protein language model, achieving a precision of 0.601, a recall of 0.422, and a specificity of 0.661. These results highlight the effectiveness of integrating ensemble learning and deep learning for allosteric site prediction. AlloPED also identifies critical determinants of allosteric sites, including residue clustering coefficients, van der Waals volume, and hydrophobic microenvironments. In summary, this framework provides a robust tool for advancing our understanding of allosteric regulation and facilitating structure-based drug design.

bioinformatics↗

Attention Guided Mechanism Interpretable Drug-Gene Interaction (MIDI) Modeling for Cancer Drug Response Prediction and Target Effect Explanation

Cancer drug discovery using genetic information is still poorly developed. Precisely locating drug atoms and explaining the targeting effect is crucial in precision medicine since it helps understand the drugs mechanism of action. Much data has been collected regarding drug response against cancer cell lines, and many models predict the drug response based on genomic information. However, to our knowledge, none of the data-driven techniques propose to detect the targeting mechanism of small drug molecules against genetic targets. In this work, we propose MIDI (Mechanism Interpretable Drug-Gene Interaction) model to delve deep into the targeting relation between drug molecules against genetic patterns. We show that purely based on a data-driven approach, the attention mechanism in our model could capture the important binding effect of small molecules towards gene targets. We provide both theoretical derivation and experiment results to show the information flow regarding the attention mechanism. In the meantime, we demonstrate that our model presents much higher prediction performance with the interpretation mechanism than the other state-of-the-art drug response prediction models.

cancer biology↗

MiR-126 Improves the Therapeutic Effect of EPC in Hypertensive Ischemic Stroke

Background and PurposeHypertension promotes circulatory endothelial inflammation, reduces endothelial progenitor cell (EPC) function, and impairs their therapeutic potential following ischemic stroke. MiR-126 is known to regulate vascular development and angiogenesis. This study investigates the therapeutic potential of miR-126 by overexpressing it in EPCs to enhance their efficacy in hypertensive stroke conditions. MethodsAdult spontaneously hypertensive rats (SHRs, n=118) underwent permanent suture middle cerebral artery occlusion (MCAO) to induce ischemic stroke. One week post-stroke, animals were injected with EPCs overexpressing miR-126 or control EPCs. Treatment effects were evaluated over 35 days, using neurological scoring, infarct volume measurements, behavioral testing, and assessments of neuroinflammation, blood pressure, and angiogenesis. Exosomes from miR-126 overexpressing EPCs were isolated and analyzed for mechanistic studies. ResultsIn vitro, miR-126 enhanced EPC angiogenic function under stress. In vivo, miR-126 modified EPC treatment improved functional recovery, reduced infarct volume, and promoted angiogenesis compared to controls in SHRs. Furthermore, miR-126 treatment preserved the blood-brain barrier, reduced peripheral immune cell infiltration, and modulated neuroinflammation. Exosomes derived from miR-126 overexpression EPCs also promoted angiogenesis and reduced endothelial activation under stress conditions. ConclusionsEPC overexpressing miR-126 provides neuroprotection by enhancing angiogenesis, reducing ischemic injury, and preserving blood-brain barrier integrity in hypertensive stroke models. This approach modulates neuroinflammation and improves neurological outcomes, suggesting gene-modified EPCs as a promising strategy for ischemic stroke therapy, particularly under hypertensive conditions.

neuroscience↗