Biology subjects

Li, H.

Publications and source records attributed to Li, H..

At least 253 records · Page 14Linked to original sources

bioRxiv2026

Chromatin context-dependent deacetylation by the asymmetric Rpd3L

The regulation of gene expression requires precise control of chromatin-associated complexes that respond to diverse structural and epigenetic cues. The Rpd3 Large (Rpd3L) complex is a Sin3 histone deacetylase (HDAC) complex that dynamically adapt to chromatin states to reinforce transcriptional silencing, yet the mechanisms governing the catalytic activation in chromatin context-dependent manner remain unclear. Here we present the cryo-EM structure of Rpd3L bound to both mono- and di-nucleosome substrate at near-atomic resolution, uncovering a substrate-guided allosteric activation mechanism. Rpd3L adopts an asymmetric architecture, in which the proximal catalytic module anchors the first nucleosome, while the Sin3 PAH domains engage linker DNA to reposition a second nucleosome. This spatial configuration brings the distal catalytic module into proximity with chromatin and unlocks its latent deacetylase activity. Biochemical and mass spectrometry analyses confirm that dual nucleosome engagement selectively enhances Rpd3L activity and broadens substrate specificity. Together, these findings establish a hierarchical mechanism by which Rpd3L interprets histone modifications and nucleosome organization to modulate its enzymatic output at promoter regions. Our study provides a framework for understanding higher-order chromatin repression mechanisms by chromatin-regulation complexes and co-repressors.

molecular biology↗

bioRxiv2026

Targeting matrix metalloproteinase-14 disrupts DNA repair and reduces viability in adrenocortical carcinoma

BackgroundAdrenocortical carcinoma (ACC) is a rare and aggressive endocrine cancer with limited treatment options and poor prognosis. Identifying novel therapeutic targets requires understanding the molecular drivers of ACC progression and establishing translational models for preclinical validation. ResultsMatrix metalloproteinase-14 (MMP-14) is the most highly expressed MMP in ACC, and high MMP-14 expression is associated with worse overall and disease-free survival. We demonstrate that MMP-14 is essential for ACC cell survival and serves an unexpected role in maintaining genome stability. Genetic silencing or pharmacologic inhibition of MMP-14 significantly reduced viability in both NCI-H295R cells and patient-derived tumor organoids (PTOs). MMP-14 knockdown induced CHK1 activation and S-phase checkpoint arrest. Mechanistically, MMP-14 translocates to the nucleus and binds to chromatin following DNA damage induced by ionizing radiation or cisplatin. Loss of MMP-14 resulted in accumulation of DNA double-strand breaks, as evidenced by increased {gamma}H2AX foci, and impaired non-homologous end joining (NHEJ)-mediated repair. ConclusionsThese findings reveal a novel nuclear function for MMP-14 in DNA repair and identify MMP-14 as a promising therapeutic target in ACC. Targeting MMP-14 may sensitize ACC tumors to DNA-damaging chemotherapy by impairing the repair of therapy-induced lesions.

cancer biology↗

bioRxiv2026

IFNγ-Driven Inflammatory Responses in the Nasal Mucosa Drive Influenza Virus Shedding and Transmission

What determines host infectiousness during influenza A virus (IAV) infection remains a fundamental unanswered question in virology. While upper respiratory tract (URT) replication is necessary for transmission, its insufficient to explain host-to-host variation in contagiousness. Using the infant mouse model of influenza transmission, we show that viruses containing H3 hemagglutinin shed at higher levels than non-H3-containing viruses, despite comparable URT replication. H3-containing virus infection was associated with higher URT inflammation, characterized by increased cytokine production, immune cell recruitment, and mucus hypersecretion, which directly correlated with shedding efficiency. Transcriptomic profiling identified enrichment of interferon-stimulated gene programs, with a dominant interferon gamma (IFN{gamma}) signature during H3 infections. Functional studies demonstrated that IFN{gamma} deficiency reduced mucus production, shedding, and transmission, whereas IFN{gamma} supplementation restored these phenotypes. Together, these findings identify IFN{gamma}-driven mucosal inflammation key host determinant of influenza infectiousness, reframing contagiousness as a consequence of host inflammatory clearance rather than viral replication alone.

microbiology↗

bioRxiv2026

MR-μScope: a multi-scale and simultaneous MRI-miniaturized microscopy system for elucidating neurovascular coupling

Blood Oxygen Level Dependent functional MRI (BOLD-fMRI) revolutionized non-invasive brain mapping, yet the physiological origins of its signal, linking microscopic neurovascular activity to macroscopic hemodynamics, remain elusive. To bridge this gap, we developed MR-Scope: a simultaneous and multimodal platform that integrates preclinic high-field MRI (9.4T) and miniaturized fluorescence microscopy (Miniscope). Our system contains an MR-compatible Miniscope with electromagnetic shielding, a customized radiofrequency coil with a central optical window, and an adjustable animal cradle, enabling artifact-free acquisition of whole-brain fMRI alongside microscopic vascular dynamics. Phantom validation confirmed negligible cross-modal interference (fMRI SNR [≥] 15 dB; optical SNR [≥] 26 dB). MR-Scope captured stimulus-evoked microvascular dilation and blood flow velocity changes in the somatosensory cortex concurrent with BOLD signals, revealing vessel-size-dependent neurovascular coupling. MR-Scope provides an effective solution for deciphering multi-scale neurovascular interactions and offers unique potential for advancing research into brain function and disease mechanisms involving vascular pathology.

bioengineering↗

bioRxiv2026

TRPV4 Inhibition by a Natural Product Mediates Analgesia

The transient receptor potential vanilloid 4 (TRPV4) channel, a polymodal calcium-permeable cation channel, is activated by diverse stimuli, including hyposmolarity, moderate heat, mechanical stress, and acidic pH. TRPV4 plays a critical role in the onset and progression of pain and is implicated in multiple pathological conditions, positioning it as an attractive therapeutic target. However, the development of TRPV4-targeted therapeutics has been hindered by limited mechanistic understanding of its inhibition. Here, the natural product (R)-1-(3-ethylphenyl)ethane-1,2-diol (AH001) is identified as a potent, subtype-selective TRPV4 inhibitor. A potential gating mechanism of TRPV4 inhibition is proposed through a combination of structural analyses and site-directed mutagenesis. Electrophysiological studies and cryo-electron microscopy (cryo-EM) further reveal that AH001s glucuronide metabolite, AHP, retains robust TRPV4 inhibitory activity, providing a critical structural basis for rational optimization of AH001 as a lead compound. Notably, AH001 demonstrated significant efficacy in reducing neuronal hyperexcitability in dorsal root ganglia (DRGs) and produced pronounced analgesic effects across multiple pain models, highlighting its therapeutic potential in pain relief. This study offers critical structural and mechanistic insights into TRPV4 inhibition and lays the groundwork for the structure-based design of TRPV4-targeted therapeutics.

biochemistry↗

bioRxiv2025

Multimodal AI for Single cfDNA Profiling and Cancer Screening

Cell-free DNA (cfDNA) serves as a non-invasive biomarker for cancer detection, but conventional methods face challenges due to the ultra-low abundance of tumor-derived cfDNA (ctDNA) among normal cfDNA. Though nucleosome-bound cfDNA harbors rich epigenomic features that could enable ctDNA identification by single-molecule multi-omics cross-validation, this remains unexplored due to methodological limits. Here, we developed a cfDNA sequencing approach integrating methylation, fragmentomics, and histone modifications at the single-molecule level; together with gene semantics and epigenomic annotations, these modalities were vectorized and fused to represent each cfDNA molecule. We trained a Transformer-based model (cfAI) to profile and evaluate ctDNA likelihood at molecule, gene, and sample levels. cfAI achieved [~]10-fold enrichment of cancer-derived signals over noise and reached 72.6% sensitivity at 93.1% specificity for multi-cancer detection. Our study establishes an innovative framework that overcomes the inherent signal-to-noise limitations of conventional assays and reveals biological features at molecular resolution for cancer detection.

bioinformatics↗

bioRxiv2025

Template-based RNA structure prediction advanced through a blind code competition

Automatically predicting RNA 3D structure from sequence remains an unsolved challenge in biology and biotechnology. Here, we describe a Kaggle code competition engaging over 1700 teams and 43 previously unreleased structures to tackle this challenge. The top three submitted algorithms achieved scores within statistical error of the winners of the recent CASP16 competition. Unexpectedly, the top Kaggle strategy involved a pipeline for discovering 3D templates, without the use of deep learning. We integrated this template-modeling pipeline and other Kaggle strategies to develop a single model RNAPro that retrospectively outperformed individual Kaggle models on the same test set. These results suggest a growing importance of template-based modeling in RNA structure prediction.

biophysics↗

bioRxiv2025

Decoupling Efficacy from Toxicity: Engineering Spatial Control in AAV-Mediated Gene Therapy

Hepatotoxicity poses a critical safety challenge for AAV-mediated gene therapy. To mitigate this, we evaluated strategies to minimize off-target hepatic transduction using an antibody expression model. We compared (i) muscle-restricted wild-type AAV9 expression and (ii) a novel myotropic capsid variant, AAV.eM. In humanized B-NDG mice bearing Raji-Luc lymphomas, intravenous administration of AAV9-MHCK7 encoding an CD19CD3 bispecific T-cell engager failed to reduce tumor burden. Conversely AAV.eM-MHCK7-CD19CD3 substantially alleviated tumor burden and achieved lymphoma clearance. By leveraging tissue-specific microRNAs, precise restriction of AAV.eM-mediated transgene expression to skeletal or cardiac muscle was achieved. Incorporating a heart-specific miR-208a binding site into the transgenes 3UTR did not compromise therapeutic efficacy when delivered via AAV.eM-MHCK7. Intramuscular delivery of AAV9-MHCK7-CD19CD3 or AAV.eM-MHCK7-CD19CD3 both cleared Raji-Luc tumors at a dose of 5 x 1012 vg/kg, underscoring the advantage of localized and targeted rAAV delivery over systemic administration. Notably, only AAV.eM-MHCK7-CD19CD3 achieved tumor eradication at a tenfold lower intramuscular dose (5 x 1011 vg/kg), reducing manufacturing costs and risks of dose-dependent immunogenicity and toxicity. Our findings demonstrate that combining tissue-specific targeting--via engineered capsids or tissue-selective promoters--with local delivery robustly reduces off-target hepatic expression, providing a strategic framework for enhancing the safety of AAV-based gene therapies.

cancer biology↗

bioRxiv2025

Large generative mRNA language foundation model for efficient coding sequence generation and design with mRNA-GPT

mRNA design plays a central role in synthetic biology, nucleic acid therapeutics, and vaccine development. Although large language models are applied in many biological fields, generative language models for de novo mRNA design remains largely unexplored. Here, we introduce mRNA-GPT, a series of generative mRNA language models which for the first time covers the three domains of life as pretraining datasets. Based on a GPT-2 transformer architecture with 302 million parameters, we pre-trained three separate models on 19,676 bacterial, 4,688 eukaryotic, and 702 archaeal species, leveraging 80 million, 83 million, and 2 million mRNA coding sequences, respectively. Distinct clustering of mRNA coding sequence embeddings from animals, plants, and fungi in the pretrained mRNA-GPT-eukaryote indicates that the model captures organism-specific sequence features. Following unsupervised pre-training, we fine-tuned mRNA-GPT on a translation-efficiency dataset to generate high-performance mRNA sequence. Compared to the pretrained model, the fine-tuned mRNA-GPT produced mRNA sequences with significantly higher translation efficiency scores, demonstrating the ability of mRNA-GPT to capture sequence features underlying high translation efficiency. We further fine-tuned mRNA-GPT on datasets for mRNA stability and mRNA expression, where it likewise produced high-performance mRNA sequences. Our pretrained models are publicly available, enabling other researchers to adapt mRNA-GPT to specialized tasks such as tissue-specific mRNA expression or stability by fine-tuning on their own data. Together, our study demonstrates that generative mRNA language modeling as a promising approach for accelerating mRNA design across diverse biological fields.

bioinformatics↗

bioRxiv2025

Gene-by-Environment Interaction Significantly Drives Bacterial Endophyte Communities in Maize Stalks

1.BackgroundMany microbes are known to boost the performance of crop plants, and their use as crop treatments ("biologicals") is an active area of research and commercialization. Although many identified microbes can boost plant production under laboratory settings, most fail to translate to field settings, and even the ones that are commercialized are often unreliable. While many factors likely underlie these issues, one that has been underexplored is the idea that interactions between plants and microbes can vary across both different host genetics and different environments, and that specific combinations of host and environment can result in very different microbial outcomes. ResultsTo quantify how a plant microbiome can change across host genotype and environment and to determine the relative importance of these factors, we sampled maize stalks from 20 specific hybrid varieties grown at 15 locations in the United States. Using 16S rRNA gene sequencing, we find that the stalk microbiome is highly variable, with a handful of bacterial taxa conserved at broader taxonomic levels (Phylum, Class) and almost none at finer levels (Genus, Species). Local environment and gene-by-environment interactions both had consistently large and significant effects on the microbial community (measured by alpha-and beta-diversity summary statistics, individual taxa, and inferred functional capacity), whereas host genotype had little to no consistent effect across environments. We also identified specific soil factors (pH and potassium) as the most significant environmental drivers of the community, even though these communities were living inside the stalks. ConclusionsTaken together, our results indicate that while host genetics can significantly affect the stalk microbial community, these effects are almost entirely predicated on interactions with the environment. These results imply that reliable deployment of microbes for crop production will require significant investment in trials across many locations and genetic backgrounds, either to estimate the GxE effects directly or to screen for microbes whose effects are less dependent on these two factors.

microbiology↗

bioRxiv2025

Hierarchical buffering of cellular RNA polymerase II pools maintains transcriptional homeostasis

RNA polymerase II (Pol II) abundance and transcriptional output are coordinated across diverse conditions to maintain mRNA homeostasis. To determine whether Pol II acts as a limiting factor for transcription, we combined acute perturbations with quantitative single-cell imaging and genome-wide profiling. We find that transcription remains stable across 70-180% of normal Pol II levels in human cells. This robustness emerges from hierarchical buffering mechanisms operating on distinct timescales. Within tens of minutes after monoallelic depletion of Pol II subunit POLR2A, cells maintain steady transcriptional output by drawing polymerases from a nucleoplasmic reserve pool. However, over hours, cellular Pol II holoenzyme levels also recover, driven by constitutive excess POLR2A subunit production rather than feedback sensing. Finally, strong depletion over days activates additional compensatory mechanisms. Together, these results reveal how temporal separation of buffering mechanisms provides robustness to perturbations of essential machinery, illuminating how cells maintain homeostatic control of essential complexes.

cell biology↗

bioRxiv2025

Two Small Proteins Enable N2O Reduction in Acidic Environments

Denitrifying bacteria are major contributors to nitrous oxide (N2O) emissions, which rise with global soil acidification, likely because low pH impairs maturation of the periplasmic enzyme N2O reductase (NosZ) in most bacteria. While some bacteria can reduce N2O under acidic conditions, the underlying mechanism remain unclear. Here, we isolated bacteria from acidic soils and identified strains that efficiently reduce N2O at low pH. They carry two novel proteins, NosP and NosQ, along with NosZ clade I. Functional analyses of deletion mutants demonstrated that NosP and NosQ are essential for the maturation of NosZ at low pH, but are not required at circumneutral pH. Cryo-EM analysis indicates that NosPQ forms a protective complex with NosZ, safeguarding its maturation under acidic conditions. Metagenomic analysis shows that nosPQ genes are widely distributed across diverse bacterial taxa and soil types. Our findings reveal a key molecular adaptation mechanism for N2O reduction in acidic environments and provide valuable insights for developing efficient N2O mitigation strategies.

biochemistry↗

bioRxiv2025

Targeting Putrescine Homeostasis with Lactiplantibacillus plantarum PS128 to Mitigate Autism-like Behaviors in Fmr1 KO Mice

BackgroundAutism spectrum disorder (ASD) is biologically heterogeneous and has limited mechanism-informed interventions targeting core behavioral symptoms. Emerging evidence suggests that gut microbial metabolism shapes neurobehavioral outcomes, yet the specific metabolic pathways linking gut ecology to brain function remain incompletely understood. One candidate pathway is polyamine metabolism, which links microbial amino acid metabolism to host regulation and represents a plausible but underexplored contributor to ASD-related phenotypes. Notably, the psychobiotic Lactiplantibacillus plantarum PS128 has been reported to improve social behaviors in individuals with ASD, although the molecular basis for these effects is unclear. In this study, we used Fragile X mental retardation 1 knockout (Fmr1 KO) mice, a well-established ASD model, to investigate microbiota-dependent metabolic mechanisms underlying autism-like behaviors. ResultsWe found that autism-like behaviors in Fmr1 KO mice were associated with gut dysbiosis, impaired intestinal barrier integrity, disruption of the arginine-ornithine-polyamine pathway, and elevated putrescine in the prefrontal cortex (PFC). Supplementation with PS128 remodeled the gut microbiota, reduced inflammation- and disease-associated taxa, improved intestinal structure and permeability, and restored polyamine homeostasis. Targeted metabolomics revealed an increased PFC-to-serum putrescine ratio in KO mice, which was normalized following PS128 intervention. This correction was accompanied by reduced expression of polyamine transporters in the PFC, including ATP13A family members. Causal experiments supported a functional role for putrescine, as peripheral elevation of putrescine induced autism-like behaviors in wild-type mice, whereas pharmacological inhibition of putrescine synthesis ameliorated behavioral deficits in Fmr1 KO mice. ConclusionsThese findings identify putrescine metabolic dysregulation as a key contributor to autism-like phenotypes and support the existence of an ASD subtype defined by disruption of the arginine-ornithine-polyamine axis. Integrated multi-omics and causal perturbation analyses support a model in which microbiota-targeted intervention rebalances systemic polyamine regulation along the gut-brain axis, thereby improving ASD-relevant behaviors. Our work provides mechanistic evidence linking microbial metabolism to neurochemical homeostasis and highlights the translational potential of metabolic stratification in ASD. Graphical AbstractWe identify dysregulated microbiota-driven polyamine homeostasis as a causal contributor to autism-like behaviors in Fmr1 knockout mice. A psychobiotic intervention restores gut-brain metabolic balance and rescues social and repetitive behavioral deficits through coordinated microbial and host transport regulation. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/694366v2_ufig1.gif" ALT="Figure 1"> View larger version (53K): org.highwire.dtl.DTLVardef@e1e780org.highwire.dtl.DTLVardef@125a3baorg.highwire.dtl.DTLVardef@201228org.highwire.dtl.DTLVardef@1880650_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2025

Efficient calculation of fluid transport in porous media with moving boundaries

A novel hybrid model combining the lattice Boltzmann (LB) and finite difference (FD) methods is proposed to simulate transport in through a junction of actively contracting lymphatic vessels, while also handling flow of interstitial liquid in the surrounding porous tissue. Details of the dynamically flexing walls and valves in the lymphatic vessel and its near vicinity are modeled using a high-resolution LB method, whereas overall efficiency was significantly improved by using low-resolution FD in the larger tissue domain distant from the vessel. Pressure and velocity conditions at the interface between subdomains of the two numerical methods are matched by imposing a partial bounce-back ratio in LB corresponding to the permeability coefficient{kappa} in Darcys law for flow through porous media. Parameters governing the match between the algorithms at their interface can be estimated from the Kozeny-Carman relationship for porous media and further refined with a simpler, parallel flow geometry that also serves to validate the method. Test calculations show that the hybrid method is roughly four times faster than the LB method and permits computation over significantly larger domains. This method should be applicable to a large range of problems involving fluid flow in porous media with embedded conduits that have non-stationary boundaries. Author summaryIt is generally acknowledged that the finite difference method (FDM) is faster and requires less memory than the lattice Boltzmann method (LBM) for comparable domain sizes. However, LBM performs better for simulating fluid flow near complex, deformable, or moving boundaries. For this reason, it can be beneficial to create hybrid models that combine FDM and LBM. In this work, we use such a hybrid model to simulate a contracting lymphatic bifurcation in fluid. Our goal is to demonstrate the models robustness and high efficiency.

bioengineering↗

bioRxiv2025

Structural and biochemical studies of human PP2A(B55) holoenzyme and ENSA protein complex

The serine/threonine protein phosphatase 2A (B55) holoenzyme (PP2A(B55)), a key cell cycle regulator, is tightly regulated by ENSA, whose phosphorylation at Ser67 inhibits PP2A(B55). The structural basis for how pENSA orchestrates this inhibition to govern mitotic progression remains unclear. In this study, we disapproved the previous hypothesis of direct ENSA-PP2A A subunit interaction, and showed that the ENSA-PP2A(B55) interaction requires the PP2A holoenzyme. We then determined cryo-EM structure of the PP2A(B55)-ENSAS67D complex at 3.03 [A] resolution, which reveals four distinct regions of ENSA, each engaging specific sites on the B55 or C subunits. The structure reveals an extended, inhibited conformation of the PP2A(B55) holoenzyme, which contrasts sharply with the contracted, active state of apo PP2A(B55). pENSA binding induces the C subunit to shift away from the B55 subunit, with the pS67-containing motif inserting into the catalytic site of C subunit and locking the PP2A(B55) holoenzyme in an inactive state. Our work also revealed novel ligand-binding surfaces on B55, and expanded definition of the short linear motif (SliM). Overall, our work provided novel insights into PP2A regulation during cell cycle, and offers new avenues for the discovery of specific PP2A(B55) inhibitors and modulators.

biophysics↗

bioRxiv2025

Exudate-Guided Janus Trilayer Bioelectronic Dressing for Multimodal Sensing and Therapy of Chronic Wounds

Chronic wound treatment remains challenging because conventional dressings and systemic therapies typically lack real-time adaptability to the dynamic changes in the wound microenvironment. Here, we report a breathable self-adhesive multifunctional wound dressing based on a gradient-wettable Janus trilayer fibrous membrane, which integrates real-time biochemical sensing, on-demand drug release, and low-voltage electrical stimulation therapy simultaneously. The dressing features a vertically integrated trilayer architecture with hierarchical partitioning, where the three vertically stacked layers integrate a multiplex electrochemical sensor array (glucose, lactate, pH), a silver-sulfadiazine drug reservoir, and stimulation electrodes. Specifically, a hydrophilic sensing layer, intermediate drug-storage layer, and hydrophobic adhesivelayer are assembled to achieve spatially resolved functionalities. The membranes gradient wettability and asymmetric porous structure enable directional exudate transport, thereby triggering stepwise activation of sensing, drug release, and electrical stimulation in a spatiotemporally controlled manner. The dressing is thin, breathable, stretchable, self-adhesive and biocompatible, enabling conformal contact and stable signal acquisition on deformable skin without tapes. This design ensures continuous bio-signal monitoring while maintaining a favorable wound healing microenvironment. Preclinical tests demonstrate its effectiveness in promoting wound closure, reducing infection, and providing continuous wound status monitoring. This integrated system offers a promising approach for next-generation wound care and regenerative medicine.

bioengineering↗

bioRxiv2025

An in situ generated CAR-M with IFNg and negative dominance Sirpa isoform augments hepatocellular carcinoma immunotherapy

Background and AimsChimeric antigen receptor (CAR) T cells have shown strong efficacy in hematological cancers but limited success in solid tumors. Macrophages, with their natural ability to infiltrate tumors, modulate immunity, and phagocytose cancer cells, offer a promising alternative when engineered with CARs. While studies have demonstrated the feasibility and anti-tumor activity of CAR macrophages (CAR-M), enhancing their persistence and phagocytic capacity remains a key challenge. Methods and ResultsBuilding on first-generation CD3{zeta}-based CAR-M, we developed a novel CAR targeting human GPC3, incorporating IFN-{gamma} and the extracellular domain of SIRP (SIRPECD) to improve CAR-M persistence and block the CD47-SIRP immune checkpoint. Following delivery via lipid nanoparticle-encapsulated mRNA (LNP-mRNA), the self-secreted IFN-{gamma} sustained M1 polarization through phospho-STAT1 activation. Meanwhile, the ectopically expressed SIRPECD competitively bound to CD47 on tumor cells, thereby blocking the endogenous SIRP-SHP2 interaction in a dominant-negative manner. This design enhanced pro-inflammatory activity and anti-tumor efficacy compared to CD3{zeta}-only CAR-M. Single-cell RNA sequencing and cellular analysis showed that in situ programmed CAR-M reprogrammed the tumor microenvironment toward inflammation in a murine HCC model. Moreover, CAR-M derived from human peripheral blood mononuclear cells (PBMCs) effectively phagocytosed human HCC organoids while sparing healthy tissues, indicating clinical potential. ConclusionsCollectively, our work presents a novel CAR design that enhances phagocytic function and sustains anti-tumor activity, offering a promising strategy for human solid tumor immunotherapy.

cancer biology↗

bioRxiv2025

Astrocyte cell-surface proteomics identified CD44 as an OPN/SPP1 receptor regulating lipid metabolism and glial crosstalk in Alzheimer s disease

Abstract/SummaryThe development of {beta}-amyloid (A{beta}) pathology in Alzheimers disease (AD) is accompanied by profound changes in astrocytes and microglia. How these responses are orchestrated by cell surface proteins, key mediators of cell-cell communication, remain unclear. Using in situ astrocyte cell-surface proteome profiling in 5xFAD mice, we identified a set of dysregulated surface proteins induced by A{beta} pathology, including CD44. CD44 was selectively upregulated in plaque-adjacent astrocytes and interacted with osteopontin (OPN), encoded by the disease-associated microglia gene Spp1, to promote lipid accumulation, and this effect is {gamma}-secretase dependent. Astrocytic CD44 in turn regulated Spp1 expression and microglial activity. Conditional deletion of Cd44 in adult astrocytes of 5xFAD mice attenuated glial reactivity, reduced A{beta} pathology, and improved cognition. These findings define a plaque-proximal OPN-CD44 axis that controls astrocyte lipid metabolism and glial activity, positioning CD44 as a surface-accessible therapeutic target in AD.

neuroscience↗