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Huang, B.

Publications and source records attributed to Huang, B..

At least 19 recordsLinked to original sources

Integrative multi-omics re-analysis of public sequencing and metabolomics repositories defines the mucosal immune and metabolic landscape of Helicobacter pylori infection and supports CagW as a rational mRNA-LNP vaccine antigen

Background. Helicobacter pylori colonises 40-45% of the global population, is a WHO Group I carcinogen, and is increasingly hard to eradicate amid rising resistance; no vaccine is licensed. CagW, a VirB6-family cagPAI component, has been advanced as a DNA-vaccine antigen that protects mice; a codon-optimised CagW-Fc mRNA in lipid nanoparticles (mRNA-LNP) is a candidate antigen design intended to engage humoral and cellular immunity. To define the infected gastric mucosal niche in which such a vaccine must operate, we mined public sequencing, single-cell and metabolomics repositories. Methods. NCBI GEO, MetaboLights and NCBI Protein were interrogated. Bulk transcriptomes of H. pylori-infected vs uninfected gastric epithelial cells (GSE295523; 24 libraries: HGC27, AGS, MKN45, GES-1) were re-analysed with a cell-line-blocked design; DEGs (BH-adjusted) were annotated via g:Profiler (GO, KEGG, Reactome) and 13 functional signatures scored. Single-cell composition was quantified from a mouse gastric scRNA-seq atlas (GSE224840; 16,434 cells) and sorted gastric CD8+ tissue-resident memory (TRM) vs splenic memory T cells (GSE216894). Targeted gastric metabolomics was re-analysed for epithelial ornithine decarboxylase (Odc) deletion (MTBLS3235) and cystathionine-gamma-lyase (Cth) deletion (MTBLS2851). CagW conservation was computed across 400 NCBI records (286 variants) with Kyte-Doolittle topology and four B cell epitope scales. Results. Infection induced 326 up- and 115 down-regulated genes (FDR < 0.05, |log2FC| > 1), dominated by TNF/NF-kappaB (KEGG hsa04668, P=5.5x10-11), integrated stress response (ATF4-CHAC1-DDIT3-TRIB3-ASNS) and Th17 chemokines (CXCL8 +3.43, CCL20 +1.32, CXCL1 +1.30, IL23A +1.02). MHC-I presentation rose (Delta-z +0.76; MHC-II unchanged); the arginine/polyamine module (SLC7A1 +1.19, ARG2 +1.33, SAT1 +1.50, ODC1 +0.58) was co-induced. scRNA-seq showed immune expansion in infected mucosa (39.8% vs 21.2% cells; OR 2.46; cell-level frequencies reported descriptively because cells are not independent; direction confirmed at sample level, n=4 vs 4), driven by plasmacytoid DCs (OR 8.9), neutrophils (OR 3.0), macrophages (OR 2.7) and cDCs (OR 2.1), with epithelial de-differentiation. Gastric CD8+ TRM cells showed a residency-effector program (Itgae +6.2, Cd69 +2.3, Gzmb +4.8, Ifng +5.3) with egress-gene loss (Sell -11.4, S1pr1 -9.7, Klf2 -5.2). Metabolomics confirmed both nodes: Odc deletion raised arginine (+3.08) and Cth deletion raised spermidine (+0.40) while lowering leukotriene B4 (-0.33). CagW was conserved across 286 variants (median 98.3% identity; 96.4% residues >=95% conserved), carried four transmembrane helices, and showed a surface-biased conserved epitope envelope at residues 505-530 and 63-79. Conclusions. Public multi-omics define an NF-kappaB/ATF4-driven, Th17-polarised, metabolically stressed niche where antigen-presenting cells expand, epithelium de-differentiates, and CD8+ TRM cells act locally. Here CagW is exceptional among cagPAI antigens: near-universal conservation plus an accessible, conserved surface. These findings provide a systems-level rationale for prioritising CagW as a conserved, epitope-accessible vaccine antigen and inform next-generation multi-antigen designs.

microbiology↗

Integrative multi-omics decoding of the host response to Klebsiella pneumoniae infection reveals an itaconate-centred metabolic-immune axis and a spatially organised inflammatory programme

Background: Klebsiella pneumoniae (Kp) is a leading cause of hospital and community acquired pneumonia and bacteraemia, and hypervirulent and carbapenem resistant lineages continue to expand worldwide. Although individual omics layers of Kp infection have been profiled, the host-level molecular logic that connects transcriptional, cellular, metabolic and spatial programmes has not been systematically integrated. Methods: We curated 16 public datasets spanning four modalities-bulk and dual host pathogen RNA-seq (six datasets; 118 libraries), single-cell RNA-seq (four datasets; {approx}164,000 cells), untargeted/targeted metabolomics (four datasets; 1,842 molecular features) and Visium spatial transcriptomics (two datasets; {approx}11,400 spots) covering murine lung infection models, hypervirulent and classical Kp strains, carbapenem-resistant isolates and human clinical specimens. Datasets were harmonised through a standardised pipeline (Salmon/DESeq2; Scanpy/Harmony; MetaboAnalyst; RCTD/spacexr), and integrated by WGCNA, GSVA, CellChat, Monocle3, SCENIC, joint-pathway analysis, RCTD deconvolution, and machine-learning feature selection (LASSO, random forest, SVM-RFE, XGBoost) with 1,000x bootstrap internal validation and independent external validation. Results: Kp infection evoked a coherent 920 gene neutrophil inflammatory response ({approx}520 up-/{approx}400 down-regulated genes) dominated by IL-17/TNF/NF-{kappa}B signalling, neutrophil degranulation, HIF-1-linked glycolysis and itaconate biosynthesis. A turquoise co-expression module (r = 0.86 with infection status) yielded a ten-gene hub signature (IRG1, S100A9, IL1B, CXCL2, SLC7A11, HMOX1, PTGS2, NFKBIA, LST1, FCGR3B). Single-cell profiling resolved twelve major lung lineages and eleven myeloid substates, tracing a Monocle3 trajectory from Cxcr2hi inflammatory neutrophils through an Irg1/Slc7a11hi oxidative phase into Cxcr4hi/Trem2hi suppressive states; CellChat identified S100A8/A9-TLR4 and CXCL2-CXCR2 as the most amplified axes (8.5x and 4.2x). Metabolomics revealed 30-fold pulmonary itaconate accumulation together with succinate and lactate elevation, glucose/glutamine depletion and glutathione collapse, and joint-pathway analysis positioned the TCA-cycle itaconate and ferroptosis modules as the strongest convergent perturbations. Spatial transcriptomics mapped these programmes onto five anatomical niches, with IRG1 expression peaking in the infection core (58% neutrophil content) and declining radially. A ten-gene host-response classification model reached AUC=0.958 in discovery, 0.937 in internal validation and 0.884-0.912 in two independent external cohorts (Brier score 0.071). Conclusions: By vertically integrating public multi-omics data, we define an itaconate-centred metabolic-immune axis that couples inflammatory myeloid expansion to spatially segregated metabolic niches, and we deliver a validated host-side molecular signature that discriminates Kp infection from non-infected states.

microbiology↗

An OmpX mRNA-LNP vaccine induces protective humoral and cellular immunity against Klebsiella pneumoniae in a C57BL/6 mouse model

Klebsiella pneumoniae (KP) poses a significant threat to global public health, and effective preventive measures are urgently needed. The widespread antibiotic resistance of KP underscores the critical need for vaccine-based strategies. Although numerous vaccine candidates against KP have been investigated, none has yet been licensed. mRNA-LNP vaccines against KP have only recently begun to be explored, and their ability to deliver conserved outer membrane protein antigens remains largely untested. In this study, we constructed an mRNA vaccine encoding the highly conserved outer membrane protein X (OmpX) of KP-the first mRNA-LNP vaccine targeting this antigen-and evaluated its immunogenicity and protective efficacy in mice. Immunoinformatics analyses predicted concordance between the in silico and in vivo outcomes: bioinformatics tools were used to evaluate the antigenicity, immunogenicity, physicochemical parameters, and secondary and tertiary structures of OmpX, and the C-ImmSim server was used to simulate the vaccine-elicited immune responses. We then performed mouse immunization and challenge experiments to characterize the humoral and cellular immune responses induced by the OmpX vaccine. The mRNA vaccine was immunogenic in mice, eliciting high titers of OmpX-specific antibodies. OmpX-Fc mRNA-LNPs also induced robust cell-mediated immunity, with significantly elevated IFN-{gamma} and IL-4 levels indicative of combined Th1/Th2 cellular responses. Serum from OmpX-immunized mice promoted significantly greater complement-mediated KP cell lysis than serum from the alum or luciferase mRNA-LNP control groups. Notably, OmpX-Fc mRNA-LNP immunization conferred complete protection against lethal KP challenge, with 100% survival and a significant reduction in visceral bacterial burden. These data establish a promising mRNA vaccine strategy for inducing broad immune responses and promoting serotype-independent immunity against KP.

microbiology↗

Integrative reanalysis of public intracellular and vaccine-challenge transcriptomes, informed by single-cell and metabolomic atlases, refines antigen prioritisation for next-generation veterinary Brucella vaccines

Brucellosis is the most widespread bacterial zoonosis and a leading cause of abortion and infertility in cattle, sheep, goats and pigs. The live vaccines licensed for livestock (B. abortus S19 and RB51, B. melitensis Rev.1) give incomplete protection, retain residual virulence and induce antibodies that are indistinguishable from those of field infection, and no human vaccine is licensed. Antigen discovery for safer subunit and mRNA alternatives has proceeded one candidate at a time, so it remains unclear which immunogenic proteins are abundant in the intracellular niche that protective immunity must recognise. We reanalysed four public data layers: dual RNA-sequencing of intracellular B. abortus and infected murine macrophages (GSE100914), splenic transcriptomes from vaccinated and challenged mice (GSE254248), and single-cell (PRJCA054635) and metabolomic (ST003696, ST003692) atlases. Intracellular residence induced 704 genes and repressed 249, enriching translation functions 2.9-fold. Omp28/BP26 was the second most abundant intracellular transcript (35,652 TPM; log2FC 4.25), whereas the lipoproteins omp16, omp10 and omp19 were 116-637-fold less abundant. Vaccination left a germinal-centre and TCF1+ memory imprint rather than an effector-cytokine signature. A composite score combining abundance, induction and surface exposure reorders the candidate panel, placing Omp28/BP26 and omp2b above current candidates and defining concrete priorities for veterinary vaccine development.

immunology↗

Pyroptolysins are versatile, sterol-sensing bacterial toxins

Gasdermin pores mediate cellular self-sacrifice for the immune defense pyroptosis. Here we describe how the gasdermin fold was repurposed during evolution into a membrane targeting bacterial toxin. These proteins, which we call pyroptolysins, are chimeras of gasdermins and cholesterol-dependent cytolysins. Like the cytolysins, pyroptolysins are active on cholesterol-rich membranes, but unlike cytolysins, they are poorly active on mammalian cells. Structural snapshots of the pyroptolysins confirm their dual homology and reveal pre-organized complexes primed for membrane insertion. Unexpectedly, we found the pyroptolysins to be active in vitro and in vivo on membranes with remarkably low sterol content, displaying insecticidal activity. Our results establish the gasdermin fold as a versatile pore-forming scaffold, capable of inducing cell death from the inside and the outside of cells.

microbiology↗

Blood-brain barrier-traversing multivalent TGFβ trap for anti-cancer immunomodulation of gliomas

Clinical studies have revealed that glioblastoma (GBM) is refractory to immunotherapy, such as immune checkpoint inhibitors (ICIs), due to the immunosuppressive tumor microenvironment (TME) primarily intensified by intratumoral upregulation of transforming growth factor-{beta} (TGF{beta}). Primary GBM tumor bulks are surgically removed in clinic, but invasive tumor cells infiltrated into surrounding normal brain tissue cannot be eradicated by systemic therapy due to the integral blood-brain barrier (BBB), leading to near-inevitable tumor recurrence. To address these translational challenges, we have engineered a TGF{beta}-inhibiting protein nanocage comprising human heavy-chain ferritin protein and TGF{beta} receptor II ectodomain that enables BBB penetration and multivalent TGF{beta} entrapment, respectively. We demonstrate that the nanocage platform, denoted T{beta}R2-HFt, following systemic administration, traverses the BBB, and extensively modulates immunosuppressive TME, both stromal and immune components, thereby potentiating the therapeutic efficacy of a clinically used ICI in multiple mouse glioma models. Notably, a majority of the glioma-bearing animals that received surgical tumor resection, followed by treatment with T{beta}R2-HFt and the ICI, survived the tumor and resisted tumor rechallenge, providing a potential means to control GBM in a durable manner.

bioengineering↗

Virtual experiments bridge sequence and microscopy with generative models

Large-scale screening and mapping efforts have produced vast libraries of perturbation-readout data. Converting these measurements into mechanistic insights requires models that link perturbation and genetic input to phenotypes, i.e., labels from experimental readouts, which are usually task specific. We propose a different, virtual experiment modeling approach: train generative models to recreate readouts conditioned on the experimental context, and then let established downstream models extract phenotypes from the synthetic data. As an illustrative case, we develop a bidirectional sequence-image generative framework, CELL-FM, that maps protein sequence and cellular context to fluorescence microscopy images and back, enabling in silico localization prediction, image-conditioned functional motif analysis and generation, and large-scale virtual mutagenesis revealing the amino acid features controlling condensate formation of intrinsically disordered peptides. This approach decouples representation learning from task-specific annotation, reuses rich experimental modalities across many downstream tasks, and preserves the spatial and organizational detail that hand-crafted labels often discard.

bioinformatics↗

A closed-loop reinforcement learning framework for rapid compound directed optimization

Generative artificial intelligence (AI) holds transformative potential for drug discovery, yet existing architectures typically operate in open loops without experimental feedback. Here we introduce rapid compound directed optimization (RCDO), a closed-loop reinforcement learning framework that accelerates the optimization process by bridging dry-lab computation with wet-lab feedback. RCDO couples a three-dimensional structure-guided generative model with a multi-level reward system updated after each design cycle using experimental measurements from all synthesized compounds, including inactive or developability-failed compounds. By continuously aligning the generative model with accumulated wet-lab measurements, RCDO substantially compresses optimization timelines. We evaluated RCDO through retrospective benchmarking against historical optimization trajectories and prospective wet-lab campaigns targeting ROR1, NLRP3, and NSD3. Across prospective evaluations, RCDO rapidly resolved key optimization bottlenecks within two to three design cycles: improving the oral exposure of an ROR1 inhibitor by 40-fold while maintaining antitumor efficacy, reducing CYP2C19 inhibition of an NLRP3 antagonist by 20-fold while preserving inflammasome activity, and boosting the binding affinity of an NSD3 hit by 18-fold. By directly coupling wet-lab feedback to generative learning, RCDO establishes an efficient platform for compound directed optimization, transforming AI-driven drug discovery from static generation into continuous experimental adaptation.

bioinformatics↗

Guide RNA binding induces reverse transcription bias during RT-qPCR analysis of RNA-targeting CRISPR/Cas systems

RNA-targeting CRISPR systems are commonly evaluated by RT-qPCR, but guide RNA binding can confound these measurements. We show that crRNA alone produces apparent knockdown without reducing target RNA abundance, whereas RNA sequencing remains unbiased and reveals guide-associated transcriptomic perturbations. A simple RNA denaturation step before reverse transcription restores accurate RT-qPCR quantification, providing practical guidance for RNA-targeting CRISPR analysis and guide design.

genomics↗

Asymmetric DNA targeting by RNA-guided TIGR-Tas systems

Tandem interspaced guide RNA (TIGR)-TIGR-associated (Tas) are RNA-guided defense systems, which use a dual-repeat or stem-loop tigRNA to direct a Tas dimer to DNA targets through RNA-DNA heteroduplex formation between both DNA strands. While previous work has shown the basic principles of DNA targeting, how the guide architecture influences target recognition and whether recognition and cleavage are coordinated across the two RNA-DNA heteroduplexes at a target site remain poorly understood. Here, we combine cryo-electron microscopy, biochemistry, and cell-based assays to investigate two TIGR-Tas effectors: the nuclease-lacking Peromyscus leucopus TasA (PlTasA), associated with a stem-loop tigRNA, and the nuclease-active Salicola phage TasH (SpTasH). Cryo-EM structures of PlTasA binary and ternary complexes reveal a dimeric scaffold similar to SpTasH and TaTasR with a distinct stem-loop tigRNA architecture and additional peripheral structural elements. Binding assays using DNA substrates containing local bubbles across the spacer-matching region show equivalent bubbles produced position- and spacer-dependent effects, indicating that target engagement is asymmetric in both PlTasA and SpTasH. Kinetic and cryo-EM analyses of SpTasH further reveal stepwise heteroduplex formation, with a partially engaged intermediate that undergoes substantial conformational rearrangements of the second protomer, preceding a fully paired state poised for catalytic activation. Cleavage of the two DNA strands occurs through a coordinated, slow process and productive cleavage requires stringent surveillance of both heteroduplexes. Together, these findings define a conserved, ordered mechanism of bipartite target recognition and activation shared by TIGR-Tas effectors, expanding our understanding of the molecular principles underlying programmable DNA targeting by TIGR-Tas systems.

biochemistry↗

Programming protein shape as an explicit design layer via CAD blueprint-guided diffusion

In engineering, industrial design principles link geometric form with function. In nature, global protein shape, curvature, and chirality similarly drive critical processes like membrane remodeling and cellular motility. However, explicitly programming these global features remains a challenge for generative AI. Here, we integrate computer-aided design (CAD) blueprints with diffusion models, establishing protein shape as an explicit, programmable layer. We engineered diverse, tunable architectures, including single-chain shapes, scaffolds with unusual twist handedness, and superhelical assemblies, structurally validating 31 of 59 designs via X-ray crystallography or electron microscopy. To demonstrate shape-encoded function, we coupled fluid-flow-optimized helical propellers to an F1-ATPase rotor, yielding a prototype ATP-dependent molecular swimmer. This framework translates industrial design principles to the molecular scale, enabling the programmable engineering of biomimetic architecture with emergent functions. One-sentence summaryIntegrating CAD blueprints with diffusion-based AI translates industrial design principles to the molecular scale, enabling the explicit programming of protein shapes with emergent functions.

bioengineering↗

Residual Multi-Modal Learning for Pan-Breast-Cancer Drug Response Prediction

Predicting drug sensitivity across diverse cancer cell lines remains a fundamental challenge in precision oncology, particularly for data-scarce cell lines where per-cell-line models overfit and lookup-table approaches cannot generalise to unseen biological contexts. We present DL4DR, a Two-Tower Residual Late Fusion deep learning model that addresses this challenge through content-based, identity-free genomic conditioning. The Cell Line Tower encodes each cell line as a 3 x 139 x 139 genomic image - encoding gene expression, mutation severity, and copy-number variation as RGB channels - using a convolutional encoder that maps directly from biological content, never from a cell line ID. The Compound Tower combines three complementary molecular representations: D-MPNN graph message passing, ORNN octave convolutional image features, and an ECFP hard-memorization head that preserves activity-cliff resolution. Predictions are composed as a residual sum: f = fhard +{lambda} (zC) {middle dot} fresidual, where the learned gate{lambda} modulates how much interaction signal supplements the memorization baseline. Evaluated across 51 breast cancer cell lines (136,342 records), Residual Fusion outperforms the ECFP-Only baseline in 48/51 cell lines (94.1%), with {Delta}R2 > 0.02 in 26/51 (51.0%). On the leave-cell-line-out split - the decisive test of genomic generalisation - the mean {Delta}R2 = +0.016 across all 51 lines demonstrates that the genomic encoder learns transferable biological signal beyond cell line identity. External validation on 601 cell lines across 27 cancer tissue types (CellTiter-Glo dataset; 0 cell line overlap with training) achieves median R2 = 0.627, within the range of the internal random-split performance (R2 = 0.61-0.69), confirming pan-cancer generalisation. GradCAM interpretability on the Cell Line Tower recovers TP53 among the top-five cross-cell-line genomic activators (5/51 cell lines) alongside several uncharacterised candidate genes (e.g. FSIP2, 6/51) - without any prior pathway annotation - providing partial biological validation of the learned representation, while also indicating that a substantial share of the encoders top-ranked signal corresponds to genes with no current annotation as breast cancer drivers. Code and data are available at https://github.com/bayjuan5/DL4DR.

bioinformatics↗

Structural assemblies for an RNA world

Protein homo-oligomerization widely generates symmetric assemblies for encapsulation and scaffolding. Conversely, natural RNA quaternary structures appear limited, with known RNA-only multimers predominantly forming dimers or dihedral assemblies from long transcripts. Whether short RNAs can access broader higher-order assembly space has remained unclear. Here, using cryo-EM, we show that RNAs under 200 nucleotides form three distinct structural classes: a 60-subunit viral-capsid-like icosahedron, non-caged oligomers including a trimer and a strand-exchanged dimer, and a continuous filament assembled from a 57-nucleotide RNA. These structures demonstrate that assembly complexity does not simply scale with RNA length; compact RNAs can specify architectures traditionally associated with proteins. Our findings broaden the known RNA quaternary repertoire, strengthen the structural plausibility of higher-order organization in an RNA world, and establish foundational reference architectures to guide future RNA-based self-assembling nanoparticle design. HighlightsO_LIShort RNAs reveal protein-like assembly principles for an RNA world C_LIO_LIThe first natural RNA-only T=1 icosahedral cage is a viral-capsid-like 60-mer C_LIO_LICompact RNA-RNA interfaces encode global curvature, valency and propagation C_LIO_LIRNA motifs assemble into closed cages, finite oligomers and extended filaments C_LI

evolutionary biology↗

Architecture of a portal complex embedded in the poxvirus core

Gene transcription within the viral core is a unique feature of poxvirus replication. Following entry into the cytoplasm, the poxvirus core dissociates from the lateral bodies and undergoes expansion, functioning as a compartment for early transcription. However, the mechanisms governing molecular exchange between the viral core and the host cytoplasm remain poorly understood. Here, we determine the structures of the portal complex and its pore on the poxvirus core at 7.1 [A] and 4.9 [A] resolution, respectively, using cryo-electron tomography and sub-tomogram averaging. The pore is assembled from three viral proteins, E8, E6, and L3, for which we constructed an atomic model. Structural and channel analyses reveal that the pore satisfies the geometric and electrostatic requirements for the transport of RNA and smaller negatively charged molecules, while excluding double-stranded DNA and cytosolic DNA sensors. Together, our findings establish a structural framework for understanding the assembly and function of the poxvirus portal complex and identify potential targets for antiviral intervention.

biophysics↗

β-Catenin Drives Apical-Basal Polarization to facilitate TE lineage commitment In Vitro and In Vivo

Embryo polarization is critical for the first cell fate segregation. While mechanisms underlying its initiation have been described, the intrinsic signaling pathways that regulate this process remain poorly understood. Here, we show that mouse embryonic stem cells, when aggregated under defined conditions, recapitulate the first lineage segregation to generate trophectoderm (TE)-like cell populations and undergo self-organized morphogenesis into blastocyst-like structures. In the blastoid-forming medium, we identify CHIR99021 is essential for the generation of blastoids from both ESCs and totipotent-like cells. CHIR99021 promotes cell polarization and TE differentiation by activating the WNT/{beta}-catenin pathway and upregulating associated genes. Consistent with this, genetic ablation of {beta}-catenin abolished the cell polarization and disrupted blastoid formation from ESCs, a defect that was restored by {beta}-catenin overexpression. Moreover, {beta}-catenin depletion compromised cell polarization in natural embryos. Collectively, this study establishes the Wnt/{beta}-catenin as a critical regulator initiating polarization in vitro and in mouse early embryo development.

developmental biology↗

EZH1/2 inhibition improves immunotherapy response through MHC Class II de-repression and neutrophil reprogramming

Squamous cell carcinoma of the lung is a difficult-to-treat cancer with high prevalence in the US, and particularly in Kentucky. Here, we sought to test if the EZH1/2 inhibitor valemetostat improves anti-PD1 responses in squamous cell lung cancer models, and to develop ex vivo models to test immunotherapy drug combinations. We found that valemetostat augmented anti-tumor responses to anti-PD1 therapy, led to up-regulation of tumor cell specific Major Histocompatibility Complex Class II (MHC Class II), and drove systemic neutrophil maturation. Likewise, Ezh2 knock-out mice produced neutrophils that were more apoptotic, less migratory, and less able to produce extracellular nets, but had similar ability to kill bacteria as Ezh2-WT neutrophils. To test tumor responses to differing neutrophil populations, we engineered three-dimensional air-liquid interface cultures with tumoroids, lung mesenchymal cells, and T cells, with and without bone marrow containing neutrophils and myeloid progenitors from distinct donors. Bone marrow from tumor-naive or mice with actively growing untreated tumors boosted tumoroid growth, while bone marrow from spontaneously tumor-rejected or mice with tumors treated with valemetostat was anti-tumor. MHC Class II blockade lowered the ability of bone marrow to boost tumor growth, and reduced the ability of valemetostat with anti-PD1 to reduce tumoroid growth. Patient samples revealed a strong negative correlation between EZH2 and MHC Class II, suggesting that targeting EZH2 activity could lead to marked increase in MHC Class II and improve treatment responses in lung squamous cell carcinomas.

cancer biology↗

Discovery of ARQ-501 as a potent PafA inhibitor that elevates KatG levels to potentiate isoniazid in mycobacteria

The prokaryotic ubiquitin-like protein (Pup) conjugation system (PPS), which is essential for Mycobacterium tuberculosis (Mtb) virulence but absent in humans, presents an attractive drug target. Here, we report the discovery of ARQ-501, a quinone-based, covalent, substrate-competitive inhibitor of the Pup ligase PafA. ARQ-501 exhibited potent anti-mycobacterial activity against Mtb under host-mimicking stress conditions and within macrophages. We further identified the catalase-peroxidase KatG, essential for activation of the frontline prodrug isoniazid (INH), as a pupylation substrate. ARQ-501 inhibits KatG pupylation, causing its accumulation and creating a selective synergy with INH. This quantity over quality mechanism successfully rescued INH activation by the clinically prevalent KatG S315T mutant in enzymatic assays and enhanced INH efficacy against clinical S315T isolates to variable degrees. This work identifies a novel class of PafA inhibitors and a previously unrecognized role of pupylation in regulating KatG, offering a potential therapeutic avenue to combat drug-resistant tuberculosis.

microbiology↗

A unified law for inhibitory control in active dendrites

Neuronal computation depends on the balance between excitation and inhibition, yet how this balance is implemented across the dendritic tree remains unclear. Classical views predict that inhibition should be most effective near the soma or along the path from excitation to output, but many interneuron subtypes preferentially target remote dendritic compartments. This apparent paradox is sharpened by active dendrites, where local NMDA spikes, calcium plateaus and backpropagating action potentials can make distal branches powerful contributors to somatic firing. Here we develop an analytical framework that extracts general principles of inhibition from biophysically detailed multi-compartment simulations. By reformulating the implicit voltage update of detailed neuron models as a matrix recursion, we derive exact voltage sensitivities to inhibitory synaptic perturbations. This leads to a unified {Phi}-a law: the somatic impact of inhibition factorizes into a global dendritic susceptibility term and a local synaptic perturbation term. Using this law to map inhibitory leverage and identify optimal inhibitory interventions, we show that active dendritic excitation can shift inhibitory hot zones from perisomatic regions toward distal or intermediate compartments. Across neocortical, hippocampal and striatal neuron models, the same response law explains convergent inhibitory strategies despite distinct cellular mechanisms. Our framework turns detailed numerical simulation into analytical theory, providing a general principle for how diverse dendritic inhibition controls active neurons.

neuroscience↗