Biology subjects

Yang, L.

Publications and source records attributed to Yang, L..

At least 19 recordsLinked to original sources

bioRxiv2026

An interferon-like off-switch in invertebrates: Vago4 downregulates Domeless to restrain JAK/STAT signaling

Whether invertebrates possess a functional interferon (IFN)-like system remains controversial, as canonical IFN ligands and their receptors are absent from invertebrate genomes. Although Vago proteins in Drosophila and shrimp are compelling functional analogs of IFN, direct evidence for a canonical cytokine-receptor axis and, importantly, for how such signaling is restrained to prevent excessive immune activation, has been lacking. Here, we identify Vago4 as a bona fide ligand of Domeless, the canonical type I cytokine receptor upstream of JAK/STAT signaling. Vago4 binds the extracellular CBM1 and CBM2 domains of Domeless, triggering receptor endocytosis followed by lysosomal trafficking and K27-linked ubiquitination-dependent proteasomal degradation. This ligand-induced receptor downregulation serves as a negative feedback mechanism that restrains excessive JAK/STAT activation. During acute Vibrio infection, Vago4 silencing accelerated shrimp mortality, whereas recombinant Vago4 alleviated inflammatory lesions and oxidative stress, enhanced phagocytosis, and improved survival, phenocopying JAK or STAT knockdown. Thus, by downregulating Domeless, Vago4 limits immunopathology and defines an IRF-Vago4-Domeless-JAK/STAT IFN-like axis in invertebrates, offering new insight into the evolution of IFN-mediated immune regulation.

immunology↗

bioRxiv2026

Abundance-weighted analysis and deep functional metagenomic selection reveals unrecognized diversity of soil-derived streptothricin acetyltransferases

Streptothricins (STCs) are broad-spectrum antibiotics under investigation for their therapeutic potential against antibiotic-resistant Gram-negative pathogens. However, the extent and diversity of genes that confer resistance to STCs, or their environmental resistome, remains largely unknown and is essentially limited to a handful of STC acetyltransferases. Here, we used a deep functional metagenomic approach to uncover previously unrecognized STC resistance determinants. A functional metagenomic library containing ca. 700 Gigabases of soil metagenomic DNA was selected for resistance to nourseothricin (NTC), a mixture of STC congeners, resulting in collection and sequencing of nearly 30,000 resistant clones. An abundance-weighted sequence analysis identified 265 acetyltransferase-like candidates spanning broad phylogenetic, taxonomic, and genomic diversity. Re-cloning and experimental testing of 18 candidates chosen to cover acetyltransferase sequence space confirmed that 10 conferred significant NTC resistance in Escherichia coli. Phylogenetic analyses identified three previously uncharacterized STC acetyltransferase lineages, designated as SatC, SatD, and SatE. Despite substantial sequence divergence from characterized streptothricin acetyltransferases (maximum amino acid identities of approximately 31% for SatC and SatD and up to 47.5% for SatE), these enzymes largely retained key residues associated with streptothricin binding and catalysis. In addition to strongly increasing NTC resistance, expression of the SatC construct in E. coli also significantly decreased susceptibility to the aminoglycoside antibiotics amikacin and kanamycin. Together, these findings reveal a substantially broader than previously known environmental repertoire of STC acetyltransferases and demonstrate how deep functional metagenomic selections, combined with abundance-weighted hit calling, phylogenetic analysis, and structural prediction, can uncover novel resistance functions.

microbiology↗

bioRxiv2026

Creator 1.0: Phylogeny-Guided Stagewise Pretraining for Plant Genome Foundation Models across 1,000 Species

Genomic language models have advanced DNA sequence analysis, but their applicability to plant-specific tasks and representation changes during pretraining remain poorly characterized. Here, we present Creator 1.0, a 2-billion-parameter parameter plant genome foundation model pretrained on 1,000 plant genomes using phylogeny-guided stagewise pretraining (PGSP). Training comprised 83 consecutive stages and produced 52 cumulative checkpoints associated with distinct plant orders. On GENEB, the stage 83 checkpoint ranked first among 46 models across 10 plant-related tasks, with a mean Matthews correlation coefficient (MCC) of 0.565, and fourth across all 100 tasks. Evaluation of 52 checkpoints on six plant lncRNA tasks identified different optimal stages under full-data, 10-shot and 1-shot settings, corresponding to stages 71, 72 and 29, respectively. Checkpoint performance varied across tasks, without consistent advantages for corresponding plant orders. These findings demonstrate the competitive performance of Creator 1.0 and highlight the potential of PGSP to provide task-adaptable checkpoints for plant genomic applications.

genomics↗

bioRxiv2026

Evaluating the added value of sequence models in noncoding RNA assays: a baseline-aware framework

Sequence models are evaluated against non-coding RNA assay read-outs, but prediction alone does not show what their features add to an explicit baseline. We estimated model-added-last changes in AUROC for lncRNA labels and cross-validated Spearman correlation for miRNA repression, fixing members and chromosome folds across available sources. In cross-cell CRISPRi (n = 2961), AlphaGenome increased AUROC from 0.6426 to 0.7551; adding K562 accessibility changed these values to 0.7282 and 0.7534. Corrected-source Cas13 increments ranged from -0.0161 to +0.0130 (n = 871). Separate post-audit comparisons tested fixed sequence composition, broader regularization and TargetScan aggregate identity. With expanded regularization, composition improved four baselines but reduced Cas13 AUROC by 0.0365. RNA-FM's increment was -0.0014 for CRISPRi and +0.000044 for HEK293FT after composition adjustment; small signs changed with regularization. On the same 1227 HeLa members, replacing a seed-family aggregate with an identity-supported mature-miRNA aggregate increased baseline Spearman from 0.4140 to 0.4799. RNA-FM then added 0.0170, or 0.0014 after composition adjustment. These source-row aggregates lack experimental transcript/site alignment. The results support testing baseline content, identity and regularization before interpreting residual model increments. Negative or near-zero increments do not establish absent information or equivalence. Resampling summaries remain conditional descriptions or non-joint sensitivities; calibrated confirmation, justified practical-size thresholds and pretraining-overlap verification were unavailable.

bioinformatics↗

bioRxiv2026

Pediatric brain charts reveal ADHD biotypes with distinct developmental, molecular, and therapeutic profiles

Attention-deficit/hyperactivity disorder (ADHD) exhibits profound clinical heterogeneity; however, its underlying neurobiological substrates remain unclear. Here, leveraging large - scale structural magnetic resonance imaging data from 12,663 typically developing children and 1,699 children with ADHD across Chinese and United States cohorts, we construct population specific pediatric brain charts via hierarchical Bayesian normative modeling to quantify individual deviations in cortical morphology. Data-driven clustering identifies two robust, cross - ethnically replicable ADHD biotypes: an infra - normal biotype characterized by widespread cortical thinning and a supra - normal biotype marked by cortical thickening. Multivariate analyses reveal distinct brain-behavior architectures: cortical deviations correlate preferentially with symptom severity in the infra-normal biotype but with both symptom severity and cognitive performance in the supranormal biotype. Clinically, the infra-normal biotype demonstrates a superior response to methylphenidate over atomoxetine, whereas the supra-normal biotype responds comparably to both. Transcriptomic analyses identify biotype-specific molecular signatures converging with ADHD genome-wide association study (GWAS) risk loci but exhibiting distinct expression patterns in the brain. These findings classify ADHD heterogeneity into neurobiologically distinct, clinically informed biotypes, providing a mechanistic framework for precision psychiatry in pediatric ADHD.

neuroscience↗

bioRxiv2026

KRT7 Marks an Airway Glandular Ductal Stem Cell Population That Supports Multilineage Development and Regeneration

Airway submucosal glands (SMGs) play a central role in host defense through mucus secretion, airway hydration, and mucociliary clearance. However, the hierarchical organization of glandular progenitor populations remains poorly defined, largely because SMGs are sparse and restricted to the proximal trachea in murine models. Using the ferret, a model that closely recapitulates the gland-rich submucosal architecture of human cartilaginous airways, we identify KRT7+ glandular ductal epithelial cells as a progenitor population. In both adult ferret and healthy human airways, KRT7 expression is primarily restricted to the SMG duct epithelium, where it is co-expressed with KRT19 and CD166 but only partially overlaps with ALDH1A1. During early postnatal development, KRT7 expression becomes progressively restricted to glandular ductal epithelium and is ultimately excluded from mature acinar, myoepithelial cells, and KRT5+/KRT14+ basal lineages. Fate mapping in KRT7CreER;ROSAmTmG transgenic ferrets revealed that KRT7-lineage cells serve as multipotent progenitors during SMG morphogenesis, generating both serous and mucous epithelial cells. Following severe airway injury, KRT7-lineage cells survive within gland ducts and rapidly expand to repair the damaged surface epithelium by differentiating into ciliated and secretory cells but not KRT5+ basal cells. In organoid cultures, glandular KRT7-lineage cells acquired a KRT5+ basal-like phenotype and generated multilineage epithelia with functional CFTR-mediated transport. These findings identify the KRT7+ ductal niche as a critical progenitor reservoir for airway development, homeostasis, and regeneration, with implications for cystic fibrosis therapies.

cell biology↗

bioRxiv2026

Charting sex divergence in the human brain across the lifespan

Biological sex fundamentally shapes human brain organization, but sex-specific normative neuroanatomical trajectories across the lifespan remain largely uncharted. Here, we constructed independent, sex-specific lifespan brain charts using structural neuroimaging data from 59,915 healthy individuals (29,760 males and 30,155 females) ranging in age from 266 postconception days to 100 years. By examining 296 structural phenotypes across global, cortical, and subcortical measures, these models revealed widespread sex differences in maturational timing, with males reaching peak milestones later than females. These trajectories demonstrate that sex differences evolve dynamically, with phenotype-specific windows of emergence and maximal separation. Compared with conventional sex-pooled references, sex-specific models achieved superior predictive accuracy and reduced misestimation of individual deviations in healthy populations. Across five neuropsychiatric conditions, sex-specific models improved the detection of extreme deviations and revealed both shared and sex-dependent patterns of disorder-related neuroanatomical abnormalities. These sex-specific charts establish tailored normative references for assessing brain development, ageing, and disease.

neuroscience↗

bioRxiv2026

Panvascular-JEPA: Unseen-Structure Evaluation of Factorized Predictive States for Hemodynamic Networks

Predictive representations for vascular simulation should be tested on unseen network structures and compared with the governing equations before being interpreted as general-purpose world models. We constructed a new, dimensioned but uncalibrated nodal resistance-inertance-compliance benchmark containing all 38 connected, non-isomorphic six-node graphs with five to seven edges. Twenty-four structures supplied training, validation, and new-background testing; 14 structures were wholly withheld. Across 648 parameter backgrounds and two prescribed action programs, 1,296 trajectories contained 96 forecast steps over three cycles. Four graph predictors received equal six candidate optimization searches, followed by five fixed-seed fits. Selected configurations and analysis code were locked before test trajectories were generated. Comparators included known-equation numerical integrators, an inertia-free reduction, and a five-coefficient model fitted to training trajectories. Unseen-structure mean standardized RMSE was 8.46 x 109 for four-factor OPF, 329 for single factor OPF, and 1.83 x 1031 for supervised graph prediction, compared with 1.09 x 10-4 for foursubstep known-equation integration and 6.77 x 104 for the fitted mechanism. The primary OPF-4 minus OPF-1 difference was 8.46 x 109, with a paired stratified-graph 95% percentile interval of [2.23 x 105, 2.54 x 1010]. Neural errors were strongly dependent on training seed and network structure, with extreme forecasts dominating the means. All four neural means exceeded persistence; relative performance within this comparison did not establish a usable forecasting model. The study supplies a distinct numerical test of structure transfer, factor-count control, and recursive stability. Its conclusions concern the implemented models, optimization budget, and finite graph catalogue. It establishes neither patient-specific performance nor anatomical transfer, biological remodeling, device efficacy, or clinical readiness.

bioengineering↗

bioRxiv2026

Spatial context of cellular heterogeneity in triple-negative breast cancer reveals actionable subtypes

Triple-negative breast cancer (TNBC) is an aggressive, heterogeneous disease with limited targeted treatment options. Leveraging bulk and spatial transcriptomics and cellular mapping of breast tissue from a large patient cohort, we identified three reproducible TNBC ecosystem subtypes that encode distinct spatial tumor-microenvironment architectures and clinically relevant treatment-response phenotype. Our analyses define: (1) an immune-exhausted subtype associated with immune checkpoint therapy (ICT); (2) a highly fibrotic/hypoxic subtype; and (3) a metabolically reprogrammed subtype characterized by nuclear-receptor and fatty-acid signaling. Spatial profiling further revealed subtype-specific organization of epithelial, immune, and stromal programs across tumor centers and invasive edges. Multiplexed imaging independently supported the contrasting immune-infiltrated and stromal-excluded architectures of the immune-engaged and fibrotic subtypes. The unique markers associated with the subtypes also provide the basis for subtyping and candidate therapeutic vulnerabilities. Our study provides a robust framework for personalized medicine, highlighting that targeting specific spatio-cellular architectures is critical to improving clinical outcomes.

cancer biology↗

bioRxiv2026

A 21-Color Spectral Flow Cytometry Panel for Comprehensive Immunophenotyping of Rat Tissues and a Companion 9-Color T-Cell Functional Assay

Although rats are crucial translational research models due to their immunological homology and surgical feasibility, the scarcity of conjugated antibodies has hampered high-dimensional immune profiling. To bridge this gap, we created a synergistic two-panel method that uses full-spectral flow cytometry: a 21-color comprehensive immunophenotyping panel and a 9-color intracellular cytokine staining (ICS) panel. The 21-color panel navigates the limited fluorophore pool and maps innate and adaptive lineages at high resolution. While it can be used to profile neutrophils and monocytes in peripheral blood it reaches its full potential in lymphoid organs, allowing for the simultaneous evaluation of tissue-resident macrophages, dendritic cells, T cell differentiation (including Tregs), and APC function. Based on this phenotypic paradigm, the 9-color ICS panel dissects effector T cell activation and Th1/Th2/Th17 cytokine production. Furthermore, we reserved the PE color during panel creation, allowing for the use of antibodies and probes with PE or comparable fluorophores in conjunction with this panel, hence increasing overall flexibility. This combination technique, designed for rat peripheral blood, spleen, and lymph nodes, combines panoramic phenotyping with functional analysis, offering an adaptable foundation for complicated tissue microenvironments in tumor immunology, rheumatology, and autoimmunity research.

immunology↗

bioRxiv2026

Molecular anatomy of the glomerular filtration barrier reveals topology-encoded albumin sieving

The kidney filters plasma rapidly while retaining albumin, yet where and how this selectivity is encoded within the glomerular filtration barrier remain unresolved. Here we combine cryo-electron tomography (cryo-ET) of vitrified mouse glomeruli with structure-resolved transport modelling to predict albumin passage from the native three-dimensional architecture of the barrier. Among the three barrier layers, endothelial fenestrae and the flexible Nephrin-Neph1 slit-diaphragm lattice are substantially permeable to albumin. The glomerular basement membrane (GBM) instead provides the dominant restriction through steric exclusion governed by void-network topology. In local GBM reconstructions, water traverses broadly connected void space, whereas narrow throats exclude albumin, leaving few accessible paths. To scale this mechanism to the tissue level, we combine structural statistics from local cryo-ET volumes with mesoscale measurements of GBM heterogeneity to generate representative ensembles. Integrating these ensembles with other layers predicts whole-barrier albumin sieving in close agreement with an independent measurement. The topology-driven mechanism also explains early filtration failure in Alport syndrome mice, in which collagen-IV disruption remodels the GBM network and opens albumin-accessible paths while cellular interfaces remain preserved. These findings identify the structural origin of glomerular albumin selectivity and establish a quantitative route from locally resolved architecture to tissue-scale physiology.

physiology↗

bioRxiv2026

Ambient-Condition Visualization of Metalloenzyme Reactive Intermediates Enabled by the SHINERS Paradigm

Reactive metal-oxygen intermediates are central to metalloenzyme catalysis, yet their low populations and short lifetimes make vibrational characterization under aqueous reaction conditions challenging. Here, we establish shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) as a powerful vibrational approach for visualizing reaction-associated metal-ligand signatures of reactive metalloenzyme states. Across the heme and non-heme iron enzymes TauD, VioC, CYP119, and TqaLNc, isotope-sensitive features provide vibrational information on reactive coordination states. In TauD and VioC, isotope-sensitive features provide vibrational characterization of Fe(IV)=O intermediates. In CYP119, an isotope-sensitive Fe(IV)=O vibration is assigned to P450 Compound I generated by m-CPBA, including under lauric-acid turnover conditions. Most notably, in TqaLNc, combined 18O- and 15N-sensitive vibrational responses support formation of the proposed (R)HN-Fe(IV)=O coordination state and the dynamic-coordination mechanism underlying selective C-N bond formation. These results demonstrate that SHINERS can serve as a powerful technique for the in situ vibrational visualization of reactive intermediates and their coordination states in metalloenzyme catalysis.

biochemistry↗

bioRxiv2026

A direct RNA sequencing workflow for simultaneous profiling of tRNA abundance and modifications in mouse liver

Transfer RNA (tRNA) is highly modified and difficult to profile using reverse-transcription-based sequencing. Here, we established a direct RNA sequencing (tRNA-DRS) workflow to simultaneously characterize tRNA abundance and modification signals in mouse liver. The workflow included small-RNA enrichment, deacylation, splint-adapter ligation, barcoding, reverse transcription, and nanopore sequencing on PromethION with modification-aware basecalling. From 1,678,666 raw reads, 1,421,279 (84.67%) reads were retained after 20-200 nt length filtering, and 17,094 uniquely mapped reads (MAPQ [≥] 10) were obtained. These reads covered 244 tRNA genes and represented all 23 tRNA isotypes. tRNA abundance was strongly skewed, with Asp, Gly, Ser, and Lys accounting for 56.6% of uniquely mapped reads. Read-body coverage indicated that most uniquely mapped reads spanned substantial portions of tRNA molecules (mean 71.1%, median 75.9%; 83.3% reads covering [≥]50% of the reference). Modification analysis identified 41,013 candidate sites, of which 711 passed stringent filtering (modification fraction [≥]50%, coverage [≥]5), spanning eight modification types and dominated by pseudouridine and m5C. Filtered sites showed position-specific clustering and isotype-dependent patterns. Together, these results support tRNA-DRS as a practical single-assay framework for simultaneous tRNA expression and epitranscriptomic profiling in mammalian tissue.

molecular biology↗

bioRxiv2026

Monothiol glutaredoxin DaGrxB couples iron homeostasis with redox balance to orchestrate development and virulence in the peach shoot blight fungus Diaporthe amygdali

Peach shoot blight (PSB), caused by Diaporthe amygdali, is one of the most devastating fungal diseases affecting peach production worldwide. Glutaredoxins (Grxs) are ubiquitous redox-regulatory proteins involved in antioxidant defense and iron metabolism, yet their functions in phytopathogenic fungi remain largely unknown. Here, we identified four Grxs (DaGrxA-DaGrxD) in D. amygdali. Among them, DaGrxB, a monothiol glutaredoxin, is the sole member essential for vegetative growth, asexual reproduction and virulence. DaGrxB interacts with iron-regulatory transcription factors DaHapX and DaSreA and modulates their activities via iron-dependent nucleocytoplasmic shuttling, coordinating iron acquisition and storage gene expression. During infection, D. amygdali encounters a biphasic iron environment: an inherently iron-limited host environment at early stages (1-2 dpi) followed by host-mediated iron excess (3-4 dpi), and DaGrxB is essential for navigating this transition. Consistently, deletion of either DaHAPX or DaSREA significantly reduced virulence, confirming that iron homeostasis is a critical determinant of D. amygdali virulence. Notably, deletion of DaGRXB disrupts Fe-S cluster biosynthesis, causing mitochondrial Fe2+ accumulation, impaired aconitase activity, and reduced ATP production, which triggers constitutive activation of the GSH-dependent antioxidant system, with elevated GSH/GSSG ratios, increased GR and GST activities, and reduced H2O2 levels. Exogenous GSH and H2O2 depletion both reduced virulence, suggesting that disturbed redox balance directly contributes to attenuated virulence. Additionally, the Trx domain assists the Grx domain in nucleocytoplasmic translocation through intramolecular interactions. Finally, LDH-delivered dsRNA targeting DaGRXB effectively controls PSB. Collectively, these findings reveal how a monothiol glutaredoxin integrates iron homeostasis, redox balance and virulence in a plant pathogen, providing a foundation for RNAi-based disease management.

pathology↗

bioRxiv2026

The uplift of the Qinghai-Tibetan Plateau reshaped genome architecture and diversification of Asian torrent catfishes

Tectonic uplift and mountain building are major drivers of species diversification and adaptation, yet how they reshape genome architecture and promote evolutionary innovation remains poorly understood. Here, we generated multiple chromosome-level genomes for Asian torrent catfishes (Sisoridae) and performed phylogenomic and comparative genomic analyses. Our results support an Asian origin of Sisoridae and provide a refined phylogenetic topology for catfishes. Comparative analyses revealed extensive chromosomal rearrangements during sisorid evolution, indicating highly dynamic genome architectures. The timing of sisorid diversification overlaps with major phases of regional tectonic change, and analyses of phylogenetic discordance indicate heterogeneous contributions from incomplete lineage sorting and introgression. Elevational distribution was associated with variation in estimated molecular evolutionary rates, while exploratory scans identified lineage-specific candidates for selection and convergent evolution. Candidate coding and non-coding changes occur near genes with known roles in fin development, body patterning, and liver biology, but their effects on sisorid traits remain to be tested. Together, our results demonstrate how tectonic uplift reshaped genome architecture and diversification in Asian torrent catfishes and provide new insights into the genomic basis of adaptation in mountainous freshwater ecosystems.

evolutionary biology↗

bioRxiv2026

Multi-omic profiling reveals impaired luteal resolution and CHK2-regulated inflammation in ovarian aging

The ovary ages earlier than most other organs, but the molecular mechanisms that drive this decline remain unclear. To gain more insight into this process, we profiled ovaries from young and reproductively aged mice after synchronized ovulation and found that aging was marked by the accumulation of luteal cells with increased steroidogenic, antigen presentation and inflammatory gene expression. DNA methylation was globally preserved in aged ovaries but showed focal age-associated changes at gene regulatory regions. Protein profiling identified an increase in checkpoint kinase 2 (CHK2), a DNA damage response protein encoded by the CHEK2 gene associated with the timing of natural menopause in humans. CHK2 and DNA damage markers were increased in aged mice and human ovarian somatic cells. Transient CHK2 inhibition in aged mice increased the proportion of mature oocytes and blastocyst formation and reversed inflammatory signatures in granulosa cells. These findings identify defective luteal resolution and inflammation as features of ovarian aging and suggest that CHK2 induces a reversible age-associated inflammatory signature. Our results show that reproductive decline may remain pharmacologically modifiable during ovarian aging via regulation of the inflammatory response.

molecular biology↗

bioRxiv2026

Therapeutic Potential of iPSC-Derived TH+FOXA2+ Neuronal Extracellular Vesicles in Parkinson's Disease Revealed by Organoid and Rodent Models

Background: Parkinson's disease (PD) is characterized by the progressive loss of midbrain dopaminergic (DA) neurons and aberrant alpha-synuclein (alpha-syn) aggregation, yet disease-modifying therapies that simultaneously retard neurodegeneration and foster regeneration remain lacking. Methods: In this study, we isolated extracellular vesicles (TH and FOXA2 double-positive cell-derived EVs) from TH and FOXA2 double-positive differentiated neural cells, a distinct midbrain floor-plate-derived neural cell population that co-expresses the floor-plate transcription factor FOXA2 together with TH and should therefore not be equated with conventional mature midbrain dopaminergic neurons, and systematically evaluated their therapeutic potential across three complementary models: A53T transgenic mice, 6-OHDA-lesioned rats, and 6-OHDA-treated human midbrain organoids. Integrative transcriptomic and single-cell sequencing analyses, together with toxicological evaluations in rodents and non-human primates, were performed to investigate the underlying mechanisms and safety profile. These TH and FOXA2 double-positive cells were generated using a fully suspension-based, matrix-free, and chemically defined differentiation system devoid of N2/B27 supplements and fetal bovine serum (FBS). This approach offers a simple, controllable, low-cost, and scalable platform with high batch-to-batch consistency for EV manufacturing. Throughout this study, the term "TH and FOXA2 double-positive cells" refers to this distinct TH and FOXA2 double-positive cell population and should not be interpreted as conventional terminally differentiated dopaminergic neurons. Results: Intranasal administration of TH and FOXA2 double-positive cell-derived EVs in A53T mice and 6-OHDA-lesioned rats significantly ameliorated motor deficits, increased nigral tyrosine hydroxylase (TH)-positive neuron counts, reduced alpha-syn aggregation, and suppressed gliosis. In human midbrain organoids, TH and FOXA2 double-positive cell-derived EVs preserved DA neuronal morphology and reduced GFAP and alpha-syn expression. Notably, when EVs were administered simultaneously with 6-OHDA modeling rather than after modeling was completed, the protective effect was stronger. Multi-omics analysis revealed that TH and FOXA2 double-positive cell-derived EVs reversed pathological signatures of interferon-responsive microglia and oxidative stress-adapted astrocytes, while restoring WNT- and non-canonical WNT-mediated intercellular communications. Safety evaluations showed no discernible organ toxicity. Conclusions: TH and FOXA2 double-positive cell-derived EVs exert neuroprotective effects across multiple PD models by modulating specific glial subpopulations and reinstating development-associated signaling pathways. Together with a fully suspension-based, matrix-free, and N2/B27-free differentiation process that enables low-cost, scalable, and highly reproducible manufacturing, TH and FOXA2 double-positive cell-derived EVs represent a promising therapeutic candidate for Parkinson's disease.

neuroscience↗

bioRxiv2026

Extracellular Granzyme B Promotes Melanocytorrhagy, Melanocyte Senescence and Aberrant Epidermal Differentiation in Vitiligo and Is Therapeutically Targetable

Background Vitiligo is an acquired depigmenting disorder characterised by melanocyte loss. While immune responses against melanocytes are implicated in its pathogenesis, melanocyte detachment, melanocyte senescence and aberrant epidermal differentiation are increasingly characterised as additional pathological features. Granzyme B (GzmB), classically recognised as an intracellular effector of perforin-dependent cytotoxicity, is increased in vitiligo lesions; however, its extracellular contribution to vitiligo pathology remains unclear. Objectives To determine whether extracellular GzmB contributes to depigmentation and epidermal pathological features relevant to vitiligo, and to define its cellular source and underlying mechanisms. Methods Human vitiligo skin samples, murine depigmentation models and cultured human epidermal cells were analysed. The functional effects of extracellular GzmB were examined by subcutaneous administration of recombinant GzmB in mice. A rhododendrol (RD)-induced leukoderma model was used to evaluate the disease relevance of GzmB and the therapeutic effect of topical GzmB inhibition with VTI-1002. Results GzmB-positive cells were markedly increased in active vitiligo lesions and were predominantly associated with tryptase-positive cells, with limited co-distribution with CD8 or perforin. Vitiligo lesions also showed melanocyte detachment, increased p16INK4A-positive melanocytes and aberrant keratinocyte differentiation. These pathological features were recapitulated in vivo by extracellular GzmB administration, accompanied by focal depigmentation. In cultured melanocytes, GzmB exerted no cytotoxic effects but reduced attachment strength and induced a senescence-associated phenotype characterised by decreased extracellular matrix- and adhesion-related gene expression, increased p16INK4A level, elevated senescence-associated {beta}-galactosidase activity and activation of transforming growth factor-{beta}/SMAD signalling. In keratinocytes, extracellular GzmB promoted aberrant differentiation associated with activation of p53 signalling. Topical inhibition of GzmB in RD-induced leukoderma attenuated depigmentation progression, melanocyte detachment, melanocyte senescence and abnormal epidermal differentiation. Conclusions Extracellular GzmB promotes depigmentation associated with inducing melanocyte detachment, melanocyte senescence and aberrant keratinocyte differentiation. These findings identify extracellular GzmB as a previously underrecognised pathogenic mediator and potential therapeutic target in vitiligo-associated depigmentation.

immunology↗