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Wang, L.

Publications and source records attributed to Wang, L..

At least 199 records · Page 11Linked to original sources

Glucocorticoid signaling regulates expression of the EBI3 subunit of IL-27 in neonatal macrophages: Implications for antenatal corticosteroid therapy

BackgroundHumans and mice display elevated levels of IL-27, an immunosuppressive cytokine shown to increase during neonatal bacterial sepsis and compromise survival. This study explores two hypotheses for regulation of IL-27 expression: 1) decreased DNA methylation in newborns that contributes to increased expression of IL-27 genes; 2) neonatal hormones regulate IL-27 expression through upstream hormone response elements (HREs). MethodsWhole genome methyl-seq analysis of neonatal and adult blood-derived macrophages identified differentially methylated regions (DMRs) at steady-state. Quantitative PCR (qPCR) measured expression of IL-27 genes (IL27p28 and EBI3) in human and murine neonatal macrophages stimulated in vitro with synthetic glucocorticoid or progesterone. Confocal microscopy and chromatin immunoprecipitation (ChIP) of glucocorticoid receptor (GR) assessed translocation into the nucleus and binding to the EBI3 promoter. ResultsThe IL-27p28 promoter contained DMRs that were increased in the neonatal cohort. The analysis did not identify DMRs within the EBI3 promoter. Dexamethasone stimulation increased EBI3 gene expression in human and murine neonatal macrophages. GR localized to the nucleus in response to dexamethasone and was enriched at the EBI3 upstream regulatory region. ConclusionThese data suggest glucocorticoid (GC) signaling increases EBI3 expression. This has importance in the context of antenatal GC administration that may increase IL-27 levels. Impact Statement{blacksquare} Elevated expression of IL-27 in early life impairs the host response to invasive bacterial infection in neonates. {blacksquare}Understanding the regulatory mechanisms contributing to increased IL-27 during the neonatal period is necessary to reduce susceptibility to infection in this vulnerable population. {blacksquare}The methylation status of the IL-27 genes in macrophages from neonatal and adult blood donors does not suggest regulation of differential expression with age. {blacksquare}Glucocorticoids are a signal that can induce EBI3 gene expression in a GR-dependent manner. {blacksquare}Glucocorticoid therapy for premature infants may increase IL-27 expression and promote enhanced susceptibility to infection.

immunology↗

Experimental SARS-CoV-2 infection using horseshoe bats

Horseshoe bats are known as the natural reservoir of sarbecoviruses. To understand how horseshoe bats coexist with sarbecoviruses in nature, experimental infection can provide direct evidence. However, in vivo infection studies using horseshoe bats have been lacking because of the difficulty of maintaining insectivorous bats in a laboratory setting. Here, we established a stable husbandry system for greater horseshoe bats (Rhinolophus ferrumequinum) and performed experimental infection with SARS-CoV-2. In contrast to Syrian hamsters which showed substantial viral replication, infected horseshoe bats exhibited low-level but persistent viral replication in the lung without overt disease. Histological analyses revealed that inflammatory lesions in the bat lungs were spatially restricted and temporally delayed compared with those in hamsters. Transcriptomic analyses further showed preferential activation of tissue repair pathways but limited inflammatory responses following infection. Notably, bats expressed several interferon-stimulated genes prior to infection. Our results suggest that a host strategy combining constitutive antiviral state, limited inflammation and enhanced tissue repair may result in controlled viral replication without overt disease, likely enabling horseshoe bats to coexist with sarbecoviruses.

microbiology↗

Distributed elasticity: a high-reward, moderate-risk strategy for efficient control modulation in insect flight

The environments inhabited by flying insects demand a balance between flight efficiency and flight manoeuvrability. In structural oscillators such as the insect indirect flight motor, efficiency (arising from resonance) and manoeuvrability (arising from kinematic modulation) are typically quid pro quo, with modulation incurring penalties to efficiency. Band-type resonance is a phenomenon that offers, in theory, a strategy to lessen these penalties via careful navigation through a band of efficient kinematic states. However, identifying this band is challenging: no methods exist to identify the complete band in realistic motor models, involving elasticity distributed across thorax and wing. Nor are the effects of elasticity distribution on the band known. In this work, we address both open topics. We present a suite of numerical methods for identifying the complete resonance band in general systems. Applying them to models of the insect flight motor with distributed elasticity--thoracic and wing flexion--reveals that distributed elasticity is moderate-risk but high-reward morphological feature. Well-tuned distributions expand the resonance band over fourfold whereas poorly-tuned distributions completely extinguish the resonance band. These results indicate that distributing elasticity across the insect flight motor can have adaptive value, and motivate broader work identifying distributions across species.

systems biology↗

Gq-pathway activation in hippocampal CA1 astrocytes rescues ischemia-induced memory deficits and synaptic plasticity

More than 30% of stroke survivors develop post-stroke cognitive impairment (PSCI), for which current neuron-centric therapies not only lack cellular specificity but also carry risks of adverse effects such as epilepsy. Here, we explore the therapeutic potential of astrocytes by chemogenetically activating Gq signaling in hippocampal astrocytes, which rescues memory deficits and synaptic plasticity impairments in a mouse model of ischemic stroke. Gq activation restores dendritic complexity, spine density, and long-term potentiation in hippocampal CA1 neurons. Fiber photometry further reveals that astrocytic Ca{superscript 2} signals precede neuronal activity by 600 ms during novel environment exploration, indicating that astrocytes prime memory encoding. In contrast, Gi pathway activation induces pathological neuronal hyperactivity without cognitive improvement. These findings establish that astrocytes regulate post-stroke recovery through pathway-specific calcium signaling and uncover a previously unknown temporal hierarchy in astrocyte-neuron communication during memory processing, offering a new glia-targeted strategy to overcome the limitations of current neuromodulation approaches for PSCI.

neuroscience↗

Structural basis of receptor retro-translocation in peroxisomal protein import

Peroxisomes import all matrix proteins post-translationally from the cytosol, a process that requires recycling of cargo receptors across the peroxisomal membrane. The membrane-embedded ubiquitin ligase, composed of Pex2, Pex10, and Pex12, is central to this process, but its mechanism remains unclear. Here we determined cryo-electron microscopy structures of the Saccharomyces cerevisiae Pex2-10-12 complex in closed and open states bound to Pex8, an essential factor of previously undefined function. The structures reveal how Pex2-10-12 gates its retro-translocation pore to control receptor entry and how the closed-to-open transition repositions the Pex10 RING domain to enable receptor mono-ubiquitination. Pex8 docks onto Pex2-10-12 from the matrix and guides receptors into the pore. Functional analyses show that the receptors N-terminal segment downstream of its mono-ubiquitination site initiates a loop insertion into the pore. These findings establish how Pex2-10-12 coordinates receptor recognition, retro-translocation, and ubiquitination, providing the molecular basis for receptor recycling in peroxisomal protein import.

biochemistry↗

Population and community responses to the fast, slow, and seasonal components of environmental variation

Theory suggests that different components of environmental fluctuations, from daily and seasonal cycles to multidecadal trends, can have distinct and even opposing effects on species abundances and community dynamics, depending on their specific adaptations. But empirical research that deconstructs the influence of these different cycles on communities is lacking. Here, we used long-term biological monitoring data together with flow records of rivers across New Zealand to (i) investigate the role of fast, slow, and seasonal river-flow fluctuations in structuring macroinvertebrate communities; and (ii) to assess whether life-history and mobility traits mediate the response. Using joint species distribution models, we found striking differences in taxon and community responses to the different components of river flow variation. Responses to slow fluctuations were generally stronger and better predicted by traits, while responses to seasonal fluctuations were highly heterogeneous. Fast increases in flow, typical of flooding events, had pervasive negative effects on species abundances, but the severity of impact partly depended on mobility traits. Our results suggest that different ecological mechanisms underpin the response to distinct environmental fluctuations, highlighting the value of jointly considering multiple temporal scales of variation and species functional traits to understand and predict how communities reorganise under fluctuating environmental regimes.

ecology↗

Damaging the conical morphology of HIV-1 capsid by targeting the FG-binding pocket and disfavoring pentameric subunits needed for core closure

The HIV-1 capsid is an essential viral component, targeted by the long-acting antiretroviral Lenacapavir (LEN). LEN binds to the HIV-1 capsid protein (CA) at the phenylalanine-glycine (FG) binding pocket (FGBP), a site for multiple host-factor and antiviral interactions in CA hexamers (CAHEX). Previously, we generated a chemical library to investigate the FGBP; ZW-1261, a lead compound, exhibits potent antiviral activity and strong inter-subunit interactions within CAHEX. Here, we report the molecular mechanism by which ZW-1261 affects the morphology and integrity of capsid lattice. ZW-1261 alone rapidly induces tubular CA assemblies; simultaneous addition of ZW-1261 with the assembly cofactor inositol hexaphosphate (IP6) forms morphologically distinct tubes. In mature virions, IP6 is required for the assembly of both CAHEX and CA pentamers (CAPENT). Cryogenic-electron microscopy analysis of in vitro assembled capsid-like particles (CLPs) with IP6 suggests that ZW-1261 leads to the absence of CAPENT and damages the pre-formed conical lattice. To elucidate how this FGBP-targeting antiviral impacts CAPENT, we further solved structures of CAPENT-only icosahedral assemblies (T = 1), formed by reported mutations, that were treated with ZW-1261. We find that ZW-1261 binding in these constrained T = 1 assemblies converts CAPENT to a CAHEX-like conformation. Collectively, this suggests a mechanism by which addition of FGBP-binding inhibitor to native cores leads to the absence of CAPENT, impacting capsid closure and core integrity.

molecular biology↗

DNA Damage Driven Viability Loss and Transcriptional Reprogramming in Chinese Hamster Ovary Cell Perfusion Culture

Intensified perfusion cultures promise higher yields and consistent product quality, yet extended runs frequently stall due to declining Chinese hamster ovary (CHO) cell viability at high cell density. Here, we identify DNA damage accumulation as a central, previously underappreciated driver of this limitation. Using two antibody-expressing CHO cell lines operated at a control and high cell density in perfusion bioreactors, we combined time-resolved transcriptomics with molecular, biophysical and super-resolution imaging analyses. We observed a progressive, global downregulation of DNA damage response (DDR) pathways accompanied by a time-dependent accumulation of DNA lesions. Notably, {gamma}H2AX signalling declined despite DNA damage, indicating impaired damage sensing and repair. Concomitantly, RNA polymerase II protein levels and transcriptional hub organisation were markedly reduced, consistent with widespread transcriptional dysfunction preceding loss of viability. An extended 21-day perfusion run confirmed continued viability decline beyond day 14, supporting a cumulative damage model. Comparison with HEK293 cells revealed substantially more efficient DNA repair, underscoring an intrinsically attenuated DDR in CHO cells. Together, these findings demonstrate that unrepaired DNA damage fundamentally constrains perfusion culture longevity, exposing limits of CHO genomic plasticity and highlighting DDR pathways as promising targets for host cell engineering to enhance perfusion performance.

bioengineering↗

Reconstituting Mouse Embryogenesis Ex Utero from Gastrulation to Fetal Development Reveals Maternally Independent Metabolic Programs

Mammalian development takes place inside the maternal uterus, creating technological constraints that make difficult the study of embryogenesis in live developing embryos. A central challenge for understanding the role of metabolism in mammalian development is discriminating placental and uterine-regulated signals from embryo-intrinsic processes independent of maternal influence, a process that until now has remained inseparable during gastrulation and organogenesis1-3. Ex utero culture systems allowing continuous growth of embryos during pre-gastrulation to organogenesis4,5 offer a promising solution to this challenge. Here, we present optimized ex utero culture platforms that support faithful development of mouse embryos from gastrulation (embryonic day 6.5/7.5) through the fetal period (embryonic day [~]12.5) and harnessed these platforms for dissecting metabolic transitions in vivo during embryogenesis independently of uterus and placenta. We characterized the metabolome of in utero and ex utero whole embryos, fetal organs and culture medium between embryonic days E6.5 and E12.5 by liquid chromatography mass-spectrometry (LC-MS) metabolomics, isotope tracing, and single cell transcriptomics. These datasets present a comprehensive overview of the dynamic embryonic metabolism during gastrulation and organogenesis in utero and ex utero. This analysis revealed that the midgestational metabolic switch occurring at E10.5-E11.5 is faithfully recapitulated ex utero, indicating that this transition is intrinsically programmed in embryonic tissues and does not require direct maternal or placental cues. Notably, oxygen availability modulated the extent of this transition, but elevated oxygen was insufficient to induce it prematurely, demonstrating that the switch is developmentally timed and only partially environmental-responsive. We further harnessed the ex utero platform for identifying and perturbing a mitochondrial redox shift at E7.5-E8.5 that is critical for developmental progress after gastrulation. These findings uncover the remarkable metabolic plasticity of the mammalian embryo, demonstrating its capacity to sustain growth independently of maternal inputs from the establishment of the body plan through the onset of the fetal period. Moreover, they highlight the use of long-term ex utero culture as a unique framework for dissecting the mechanisms that shape embryogenesis under physiological and experimentally perturbed conditions, while functionally uncoupling embryonic programs from maternal and placental influences.

developmental biology↗

Stromal asparagine supports tumor adaptation to oxidative phosphorylation inhibition through SLC38A4-mediated metabolic coupling

PurposePancreatic ductal adenocarcinoma (PDAC) is characterized by a nutrient-deprived and hypoxic tumor microenvironment (TME) that imposes severe metabolic stress on cancer cells. Under these conditions, tumor cells frequently activate the integrated stress response (ISR) to adapt to TME and develop resistance to therapies. However, how TME components support tumor adaptation to mitochondrial metabolic stress remains incompletely understood. Here, we aimed to identify key metabolite involved in ISR adaptation under oxidative phosphorylation (OXPHOS) inhibition and to elucidate the metabolic symbiosis between cancer-associated fibroblasts (CAFs) and PDAC cells. MethodsWe integrated transcriptomic and metabolomic analyses with functional assays. ISR activation was evaluated by assessing the phosphorylation of eIF2 (p-eIF2) following treatment with carboxyamidotriazole orotate (CTO), an Complex I inhibitor. Metabolomic profiling was used to identify metabolites involved in ISR activation alleviation. Mouse models were used to assess therapeutic responses following depletion of the identified metabolite under CTO treatment. Genetic perturbation of Slc38a4 was performed to assess its functional role in tumor cell adaptation to metabolic stress. ResultsWe identified asparagine (ASN) as a critical metabolite supplied by CAFs to PDAC cells under OXPHOS inhibition. A minimum level of ASN is required for PDAC cells to execute ISR downstream adaptation. ASN depletion significantly enhanced the anti-tumor efficacy of OXPHOS inhibition both in vitro and in vivo. SLC38A4 emerged as a potential mediator of this interaction. SLC38A4 expression was associated with c-Myc, and its loss increased the sensitivity of PDAC cells to CTO-induced metabolic stress. ConclusionOur findings reveal a CAF-tumor metabolic crosstalk in which stromal-derived ASN supports PDAC cell adaptation to mitochondrial metabolic stress. Adaptive outcome of ISR signaling depends on the availability of key metabolic substrates such as ASN. When extracellular ASN supply is limited, the ATF4-dependent adaptive program collapses, converting ISR from a pro-survival response into a therapeutic vulnerability. SLC38A4 may function as a key mediator of this metabolic coupling and represents a potential target for enhancing the efficacy of OXPHOS inhibition in PDAC.

cancer biology↗

IgG Propels Atherosclerosis by Noncanonically Activating Macrophages

Despite being a central component of adaptive immunity and a highly abundant serum protein, the contribution of IgG to the milieu of atherosclerosis remains unappreciated. Here, we identify a pro-atherogenic role for IgG as it activates an innate immune cascade, independent of its classical antigen-neutralizing function. Analyses of human coronary artery plaques reveal a positive correlation between IgG and cardiovascular and cerebrovascular disease severity. Integrated single-cell plaque analyses localize IgG, coinciding with its recycling receptor FcRn, to pro-inflammatory and foamy macrophages. Genetic ablation of FcRn in myeloid cells prevents IgG from accumulating in mouse atherosclerotic lesions, diminishing plaque size and inflammation. Mechanistically, IgG acts as an endogenous ligand for TLR4, triggering NF-{kappa}B-NLRP3 inflammasome signaling without requiring its antigen-binding domain. Additionally, IgG accelerates macrophage foam cell formation through upregulation of downstream effector LCN2. Our work uncovers a role for previously overlooked adaptive immune molecules in the pathogenesis of atherosclerosis through a noncanonical mechanism linked with innate immunity.

immunology↗

UniST: A Unified Computational Framework for 3D Spatial Transcriptomics Reconstruction

Spatial transcriptomics (ST) enables the measurement of gene expression in its native spatial context, yet most ST datasets are acquired as two-dimensional (2D) sections. Consequently, the underlying three-dimensional (3D) organization of tissues is only partially observed, and 3D ST data generated from serial sections are typically sparse and heterogeneous, with substantial tissue loss and missing measurements. These limitations pose major analytical challenges for reconstructing coherent 3D tissue architecture, rather than issues of experimental scalability alone. Here, we present UniST, a unified generative artificial intelligence (AI) framework designed to computationally reconstruct dense and continuous 3D ST landscapes from sparse serial sections, without altering the underlying experimental ST technologies. UniST integrates three complementary modules: kernel point convolution with cross-attention layers for point cloud upsampling, optical flow-based interpolation for continuous slice reconstruction, and a graph autoencoder with implicit neural representations for gene expression imputation. Together, these components densify sparse slices, resolve discontinuities, and map spatial coordinates to high-dimensional transcriptomics. Across multiple ST platforms and tissue contexts, UniST accurately restored structural continuity and biologically meaningful expression patterns. In a mouse embryo dataset, UniST reconstructed a dense 3D heart architecture from sparsely sampled slices. In two 3D human cancer tissues, UniST recovered critical spatial features, including tumor-immune boundaries and tertiary lymphoid structures, that were fragmented in the original data. By providing a generalizable computational solution that complements existing ST acquisition protocols, UniST facilitates cost-efficient and scalable reconstruction of 3D ST landscapes, enabling more faithful investigation of tissue organization and disease biology.

bioinformatics↗

pertTF: context-aware AI modeling for genome-scale and cross-system perturbation prediction

Predicting genetic perturbation responses at a single-cell level is central to building models for cell state and disease. However, existing approaches are limited on predicting phenotypic outcomes beyond expression changes and generalizing predictions across genome-scale perturbations in biologically relevant contexts. Here we introduce pertTF, a transformer-based single-cell genetic perturbation model. pertTF was trained from a unique dataset capturing single cell expressions profiles of 30 full gene knockouts across 14 relevant cell types during human pancreatic development and beta-cell differentiation. pertTF outperforms current methods in predicting expression changes of perturbing unseen genes in unseen cellular contexts. In addition, pertTF infers perturbation-induced shifts in cell identity and population composition, an important phenotypic outcome of perturbation in many physiology and disease settings. Through transfer learning, pertTF operates in physiologically relevant systems, including primary human islets, where large-scale perturbation experiments are challenging. The generalizability of pertTF is further demonstrated by in silico pooled and single-cell CRISPR screens, capturing critical regulators of stem cells and early pancreatic cell development. These results establish pertTF as a framework for integrating large-scale single-cell perturbation data with AI models to predict genetic perturbation effects across cellular systems and disease contexts.

bioinformatics↗

Integrated single-cell and spatial transcriptomic analysis of T cell exhaustion and immunometabolic remodeling in HPV-positive oropharyngeal squamous cell carcinoma

HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) harbors dense lymphocytic infiltration yet responds poorly to immune checkpoint blockade (ICB), a paradox whose mechanistic basis remains unresolved. Here we constructed an integrated single-cell and spatial transcriptomic atlas of HPV OPSCC (23,119 cells, 24 cell types), complemented by CRISPR-Cas9 functional validation in two HPV cell lines and multiplex immunofluorescence across independent cases. Pseudotime trajectory analysis placed TOXCD8 T cells, rather than canonically defined exhausted cells, at the terminal exhaustion endpoint, and uncovered a previously uncharacterized IEGCD8 effector memory population at a fate-decision juncture between activation and irreversible exhaustion. Actively cycling Tregs with broad co-stimulatory and co-inhibitory receptor expression underwent intratumoral immunosuppressive differentiation. Compartmentalized LDHA/MCT4 expression in cancer cells versus LDHB/MCT1 in T cells established a directional lactate flux model, and spatial deconvolution confirmed peripheral immune exclusion. We identified a KMT2D-KLF7-PD-L1 regulatory axis: KMT2D sustains KLF7 transcription through H3K4me1-dependent enhancer activation; KLF7 concurrently drives neural crest differentiation and upregulates PD-L1, thereby linking epigenetic remodeling to both neural programming and immune checkpoint expression. These findings define converging multi-scale mechanisms underlying ICB resistance in HPV OPSCC and nominate the KMT2D-KLF7-PD-L1 axis as a combinatorial therapeutic target.

cancer biology↗

Comprehensive long-read transcriptome analysis uncovers alternative RNA processing feature and isoform diversity in ovarian cancer progression

Post-transcriptional processing has a crucial yet largely unresolved dynamic change and role during the malignant progression of ovarian cancer, especially due to the limited read length of short-read RNA sequencing being insufficient to capture transcript diversity. Here, we performed Iso and RNA sequencing on paired normal, primary tumor, and metastatic samples, generating a comprehensive isoform atlas of over 41,000 full-length transcripts including many unannotated isoforms. Integrative analyses revealed extensive isoform-level remodeling across disease states that often occurred without concordant alterations at the gene level, emphasizing the importance of qualitative transcript regulation. Notably, we identified isoform-level alterations with distinct biological and clinical relevance, including differential expression of the short KRAS isoform, a tumor-specific isoform switch of TMEM201, and an alternative first-exon event in FNDC3B associated with poor survival. Together, these findings provide a high-resolution map of the ovarian cancer transcriptome and illustrate how long-read sequencing exposes multiple layers of post-transcriptional and clinical insight that remain hidden in conventional expression profiling.

bioinformatics↗

The Cell Surface Proteome of Malignant Peripheral Nerve Sheath Tumors Reveals Therapeutic Targets

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas and the most common cause of disease-associated death for Neurofibromatosis Type 1 (NF1) patients. In the context of NF1, MPSNTs develop from benign premalignant precursors. The transition to malignancy is usually accompanied by loss of the polycomb repressive complex 2 (PRC2), leading to aberrant upregulation of many genes. The specific mechanisms disrupted by PRC2 loss remain incompletely understood. There is a significant gap in our knowledge of which cell-surface targets become derepressed and therapeutically actionable following PRC2 loss, contributing to the current lack of effective targeted therapies for MPNSTs. This study aims to address this gap by using cell-surface capture technology with mass spectrometry to profile MPNST models. In doing so, we define PRC2-dependent effects on the cell surface proteome, including specific biological pathways that are enhanced or suppressed at the cell surface protein level. We also create an MPNST cell-surface protein compendium comprised of proteins that are highly expressed across a variety of well-defined MPNST models. We prioritized proteins that are preferentially expressed in MPNST or other cancers and for which FDA-approved therapies already exist. Specific proteins from this compendium were molecularly targeted with antibody-drug conjugates in these models to surmise their therapeutic efficacy. Results reveal PTK7 as a novel and promising target for MPNST. In total, these efforts represent a step toward addressing the knowledge gap in MPNST genesis and identifying new therapeutic targets for further testing. Additionally, this data serves as a resource for other researchers wishing to characterize specific molecular targets. KEY POINTSPRC2 modulates key MPNST signaling pathways through the cell surface proteome Cell surface proteomics identifies a plethora of therapeutic targets for MPNST targeted therapy Antibody-drug conjugates targeting PTK7 show enhanced efficacy in reducing MPNST viability IMPORTANCE OF THE STUDYThis study utilizes advances in biochemistry to profile the surface proteome of malignant peripheral nerve sheath tumors. In doing so, it identifies many proteins whose presence is abundant on the cell surface of MPNST cells. Pre-clinical drug testing shows that use of antibody-drug conjugates may be effective in killing MPNST cells when targeted to epitopes identified in our MPNST cell surface proteome compendium. This study is a departure from more commonly used transcriptomic methods to identify cell surface proteins by using direct surface capture and mass spectrometry, providing a more direct measurement of cell surface protein abundance. Additionally, it identifies a handful of proteins which can be directly targeted pharmaceutically and one in particular, PTK7, whose targeting is highly effective in killing MPNST cells.

cancer biology↗

Dual-Logistic Analysis of Time- and Concentration-Dependent Phenotypic Efficacy Evaluation Integrating Drug Targets Information

Tumor heterogeneity highlights the necessity of precision cancer medicine, making the evaluation and screening of anticancer drugs a core challenge in cancer therapy. However, current cell-based efficacy assessment methods struggle to quantify the holistic impact of drugs on cellular behavior through specific target engagement. Here, we proposed a novel approach (DL-TCP-FRET) that integrates phenotypic and target-related evaluations: the logistic fitting analysis is performed on time- and concentration-dependent cellular phenotypic characteristics to construct a phenotypic score (P), while a target score (T) is established based on the FRET efficiency between target proteins. These two scores were then further combined to generate a unified drug efficacy score (PT). Validation in A549 cells demonstrated that our method can reliably distinguish EGFR-TKIs from non-targeted drugs. DL-TCP-FRET simplifies the experimental workflow of drug efficacy evaluation and improves the accuracy of targeted drug identification, providing a novel strategy for advancing precision cancer therapy.

cell biology↗

Peptide-Induced Formation of Extracellular Vesicles that are DistinctFrom Endogenous E. coli OMVs, and Provide an Enhanced Platformfor Protein Production and Purification.

Bacterial outer membrane vesicles (OMVs), are nano-sized, spherical structures released by Gram-negative bacteria that play diverse roles in bacterial physiology, including communication, nutrient acquisition, and host interactions. These vesicles bud from the bacterial outer membrane and contain lipopolysaccharides, periplasmic proteins, nucleotides, and other biomolecules. The Vesicle Nucleating peptide (VNp) is a short peptide tag that, when fused to the amino terminus of a protein of interest, promotes the formation of bespoke recombinant extracellular vesicles in Escherichia coli, enabling efficient production and simplified purification of recombinant proteins. Here, we characterise VNp-induced vesicles and compare their composition and organisation with naturally produced E. coli OMVs. While both vesicle types possess a single outer membrane-derived lipid bilayer, recombinant protein is highly enriched within the VNp vesicles compared to endogenous OMVs. VNp-fusions and periplasm-targeted recombinant proteins localize to distinct vesicle populations, with VNp-fusions showing markedly higher intra-vesicular concentrations and vesicular purity, compared to the OMV targeted protein. OmpX co-expression further enriched the VNp-fusion content of vesicles, further enhancing yield. The VNp-vesicle lumen is an oxidizing environment, thus supports formation of inter- and intra-molecular disulfide bonds within encapsulated proteins. Overall, VNp-induced vesicles represent a distinct class of recombinant extracellular vesicles that offer a simple and efficient route for producing and purifying concentrated, correctly folded recombinant proteins, expanding the utility of bacterial vesicle systems for biotechnological applications. Significance StatementBacterial extracellular vesicles are recognized as versatile tools for biotechnology yet engineering bacterial vesicle production in a controlled and efficient manner remains challenging. Here we describe how a short Vesicle Nucleating Peptide (VNp) tag, fused to a protein of interest, that can be used to program Escherichia coli to produce recombinant extracellular vesicles that are compositionally and structurally distinct from natural bacterial outer membrane vesicles (OMVs). VNp-induced vesicles are more homogeneous, and more highly enriched in target fusion proteins, providing a simple and efficient route for protein production and purification. The oxidizing lumen of these vesicles supports disulfide bond formation, and rapid compartmentalisation enables expression of otherwise challenging or toxic proteins. This work characterises a distinct class of recombinant bacterial vesicles and establishes a practical platform for producing correctly folded, concentrated, partially purified proteins in a self-packaged form, expanding the potential applications of bacterial extracellular vesicles in biotechnology and synthetic biology.

bioengineering↗