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BackgroundPhotoreceptor death leads to inherited blinding retinal diseases,such as retinitis pigmentosa (RP). As disease progression often outpaces therapeutic advances,developing effective treatments is urgent. This study evaluates the efficacy of small peptides derived from pigment epithelium-derived factor (PEDF),which are known to restrict common cell death pathways associated with retinal diseases.MethodsWe tested chemically synthesized peptides (17-mer and H105A) with affinity for the PEDF receptor,PEDF-R,delivered as eye drops to two RP mouse models: rd10 (phosphodiesterase 6b mutation) and RhoP23H/+ (rhodopsin P23H mutation). Additionally,we engineered AAV-H105A vectors for intravitreal delivery in RhoP23H/+ mice. To assess peptide effects in human tissue,we used retinal organoids exposed to cigarette smoke extract,a model of oxidative stress. Photoreceptor survival,morphology and function were evaluated.ResultsHere we show that peptides 17-mer and H105A delivered via eye drops successfully reach the retina,promote photoreceptor survival,and improve retinal function in both RP mouse models. Intravitreal delivery of a AAV-H105A vector delays photoreceptor degeneration in RhoP23H/+ mice up to six months. In human retinal organoids,peptide H105A specifically prevents photoreceptor death induced by oxidative stress,a contributing factor to RP progression.ConclusionsPEDF peptide-based eye drops offer a promising,minimally invasive therapy to prevent photoreceptor degeneration in retinal disorders,with a favorable safety profile. Plain language summaryRetinitis pigmentosa (RP) is a rare inherited condition that causes the gradual death of photoreceptors (light-sensing cells) in the eye,leading to vision loss. There is currently no cure. This study tested a potential treatment using small protein fragments (peptides) from PEDF,a protective protein naturally found in the eye. Researchers delivered these peptides through eye drops or gene therapy in mouse models of RP and to human retinal organoids (lab-grown retina tissue). Mice treated early maintained healthy vision cells,while untreated mice experienced rapid cell loss and vision decline. These results suggest that peptide-based eye drops could be a simple,safe,and effective way to slow vision loss in patients with RP. Bernardo-Colón et al. evaluate small peptides derived from the neurotrophic region of pigment epithelium-derived factor (PEDF) as potential therapeutics for retinitis pigmentosa using mouse models and human retinal organoids. A significant delay in photoreceptor death with eye drop or gene therapy delivery is seen. View Publication

SummaryHuman pluripotent stem cell-derived neural progenitor cells (NPCs) are an essential tool for the study of brain development and developmental disorders such as autism. Here,we present a protocol to generate NPCs rapidly and reproducibly from human stem cells using dual-SMAD inhibition coupled with a brief pulse of mouse neurogenin-2 (Ngn2) overexpression. We detail the 48-h induction scheme deployed to produce these cells—termed stem cell-derived Ngn2-accelerated progenitor cells—followed by steps for expansion,purification,banking,and quality assessment.For complete details on the use and execution of this protocol,please refer to Wells et al.1 Graphical abstract Highlights•Brief pulse of Ngn2 induces neural progenitor cells from human stem cells•Guidance on expanding,freezing,and thawing SNaP cells for future use•Immunostaining-based assays assess cell identity and differentiation potential Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics. Human pluripotent stem cell-derived neural progenitor cells (NPCs) are an essential tool for the study of brain development and developmental disorders such as autism. Here,we present a protocol to generate NPCs rapidly and reproducibly from human stem cells using dual-SMAD inhibition coupled with a brief pulse of mouse neurogenin-2 (Ngn2) overexpression. We detail the 48-h induction scheme deployed to produce these cells—termed stem cell-derived Ngn2-accelerated progenitor cells—followed by steps for expansion,purification,banking,and quality assessment. View Publication

The ability to robustly predict guide RNA (gRNA) activity is a long-standing goal for CRISPR applications,as it would reduce the need to pre-screen gRNAs. Quantification of formation of short insertions and deletions (indels) after DNA cleavage by transcribed gRNAs has been typically used to measure and predict gRNA activity. We evaluate the effect of chemically synthesized Cas9 gRNAs on different cellular DNA cleavage outcomes and find that the activity of different gRNAs is largely similar and often underestimated when only indels are scored. We provide a simple linear model that reliably predicts synthetic gRNA activity across cell lines,robustly identifies inefficient gRNAs across different published datasets,and is easily accessible via online genome browser tracks. In addition,we develop a homology-directed repair efficiency prediction tool and show that unintended large-scale repair events are common for Cas9 but not for Cas12a,which may be relevant for safety in gene therapy applications. Reliable prediction of guide RNA (gRNA) activity is key for efficient CRISPR gene editing. Here,the authors show that efficiency of gRNAs is often underestimated when only indels are scored and introduce tools for predicting activity of chemically synthesized gRNAs and HDR efficiency. View Publication

To accurately study human organ function and disease ‘in the dish’,it is necessary to develop reliable cell-based models that closely track human physiology. Our interest lay with the liver,which is the largest solid organ in the body. The liver is a multifunctional and highly regenerative organ; however,severe liver damage can have dire consequences for human health. A common cause of liver damage is adverse reactions to prescription drugs. Therefore,the development of predictive liver models that capture human drug metabolism patterns is required to optimise the drug development process. In our study,we aimed to identify compounds that could improve the metabolic function of stem cell-derived liver tissue. Therefore,we screened a compound library to identify additives that improved the maturity of in vitro-engineered human tissue,with the rationale that by taking such an approach,we would be able to fine-tune neonatal and adult cytochrome P450 metabolic function in stem cell-derived liver tissue. View Publication

During gastrulation,the primitive streak (PS) forms and begins to differentiate into mesendodermal subtypes. This process involves an epithelial-mesenchymal transition (EMT),which is marked by cadherin switching,where E-Cadherin is downregulated,and N-Cadherin is upregulated. To understand the relationships between differentiation,EMT,and cadherin switching,we made measurements of these processes during differentiation of human pluripotent stem cells (hPSCs) to PS and subsequently to mesendoderm subtypes using established protocols,as well as variants in which signaling through key pathways including Activin,BMP,and Wnt were modulated. We found that perturbing signaling so that cells acquired identities ranging from anterior to posterior PS had little impact on the subsequent differentiation potential of cells but strongly impacted the degree of cadherin switching. The degree of E-Cadherin downregulation and N-Cadherin upregulation were uncorrelated and had different dependence on signaling. The exception to the broad potential of cells throughout the PS was the loss of definitive endoderm potential in cells with mid to posterior PS identities. Thus,cells induced to different PS coordinates had similar potential within the mesoderm but differed in cadherin switching. Consistently,E-Cadherin knockout did not alter cell fates outcomes during differentiation. Overall,cadherin switching and EMT are modulated independently of cell fate commitment in mesendodermal differentiation. View Publication

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by profound neuronal and cognitive decline,with increasing evidence implicating astrocyte dysfunction in disease pathology. While traditional therapeutic approaches have primarily targeted neurons,the crucial role of astrocytes in metabolism,neurotransmission,amyloid-beta clearance,and neuroinflammation underscores their potential as therapeutic targets. In this study,we employed a multiomic integrative analysis combining transcriptomic and kinomic profiling of human induced pluripotent stem cell (hiPSC)-derived astrocytes from patients with familial AD (fAD) compared to healthy controls (HCs). Our transcriptomic analysis identified 1249 significantly differentially expressed genes,highlighting a pronounced upregulation of inflammatory genes (SERPINA3,IL6R,IL1RAP,TNFRSF11A) and a concomitant downregulation of genes essential for synaptic support and ion channel function (STMN2,NMNAT2,SCN2A,GRIN1). Kinomic profiling revealed dysregulated kinase activities within DYRK,GSK,and MAPK families,further implicating altered kinase signaling pathways in astrocyte dysfunction. Integration of these datasets pinpointed critical molecular hubs,notably within the PI3K signaling and inflammatory pathways,highlighting targets such as JAK2,STAT3,and AKT1 as potential modulators of disease progression. Furthermore,leveraging the Library of Integrated Network-Based Cellular Signatures (LINCS) platform,we identified chemical perturbagens,including fluticasone propionate and Akt inhibitors,capable of reversing the transcriptomic signatures associated with fAD astrocytes. This integrative multiomic approach not only enhances our understanding of astrocyte-specific molecular mechanisms in AD but also provides novel targets for therapeutic intervention aimed at mitigating astrocyte-driven neurodegeneration. Highlights•Familial AD astrocytes display significant pro-inflammatory transcriptomic and kinomic dysregulation.•PI3K and inflammatory signaling pathways are highly dysregulated in familial AD astrocytes.•Expression of inflammatory markers such as SERPINA3,IL6R,and TNFRSF11A is increased in familial AD astrocytes.•Kinase activity analysis identifies DYRK,GSK,and MAPK pathways as key dysregulated axes in familial AD astrocytes.•Potential astrocyte-specific therapeutic approaches to AD include targeting PI3K,JAK,and STAT3. View Publication

AbstractDespite being one of the most prevalent RNA modifications,the role of N6?methyladenosine (m6A) in amyotrophic lateral sclerosis (ALS) remains ambiguous. In this investigation,we explore the contribution of genetic defects of m6A?related genes to ALS pathogenesis. We scrutinized the mutation landscape of m6A genes through a comprehensive analysis of whole?exome sequencing cohorts,encompassing 508 ALS patients and 1660 population?matched controls. Our findings reveal a noteworthy enrichment of RNA binding motif protein X?linked (RBMX) variants among ALS patients,with a significant correlation between pathogenic m6A variants and adverse clinical outcomes. Furthermore,Rbmx knockdown in NSC?34 cells overexpressing mutant TDP43Q331K results in cell death mediated by an augmented p53 response. Similarly,RBMX knockdown in ALS motor neurons derived from induced pluripotent stem cells (iPSCs) manifests morphological defects and activation of the p53 pathway. Transcriptional analysis using publicly available single?cell sequencing data from the primary motor cortex indicates that RBMX?regulated genes selectively influence excitatory neurons and exhibit enrichment in ALS?implicated pathways. Through integrated analyses,our study underscores the emerging roles played by RBMX in ALS,suggesting a potential nexus between the disease and dysregulated m6A?mediated mRNA metabolism. The dysregulation of m6A modification has gained recognition as a crucial factor in the development of amyotrophic lateral sclerosis (ALS). Among the m6A reader proteins,RNA binding motif protein X?linked (RBMX) stands out with a notable enrichment of variants in ALS patients,and the presence of pathogenic RBMX variants is associated with a faster disease progression. In vitro experiments have provided evidence that reducing RBMX levels can result in neuronal defects. Additionally,bioinformatic analyses have supported these findings by revealing that RBMX?associated genes specifically impact excitatory neurons. Furthermore,these genes are involved in the regulation of pathways and genes associated with neurodegeneration and RNA metabolism,underscoring the relevance of RBMX in ALS pathogenesis. View Publication

BackgroundCertain structural variants (SVs) including large-scale genetic copy number variants,as well as copy number-neutral inversions and translocations may not all be resolved by chromosome karyotype studies. The identification of genetic risk factors for Parkinson’s disease (PD) has been primarily focused on the gene-disruptive single nucleotide variants. In contrast,larger SVs,which may significantly influence human phenotypes,have been largely underexplored. Optical genomic mapping (OGM) represents a novel approach that offers greater sensitivity and resolution for detecting SVs. In this study,we used induced pluripotent stem cell (iPSC) lines of patients with PD-linked SNCA and PRKN variants as a proof of concept to (i) show the detection of pathogenic SVs in PD with OGM and (ii) provide a comprehensive screening of genetic abnormalities in iPSCs.ResultsOGM detected SNCA gene triplication and duplication in patient-derived iPSC lines,which were not identified by long-read sequencing. Additionally,various exon deletions were confirmed by OGM in the PRKN gene of iPSCs,of which exon 3–5 and exon 2 deletions were unable to phase with conventional multiplex-ligation-dependent probe amplification. In terms of chromosomal abnormalities in iPSCs,no gene fusions,no aneuploidy but two balanced inter-chromosomal translocations were detected in one line that were absent in the parental fibroblasts and not identified by routine single nucleotide variant karyotyping.ConclusionsIn summary,OGM can detect pathogenic SVs in PD-linked genes as well as reveal genomic abnormalities for iPSCs that were not identified by other techniques,which is supportive for OGM’s future use in gene discovery and iPSC line screening.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12864-024-10902-1. View Publication

Diabetic keratopathy (DK),a significant complication of diabetes,often leads to corneal damage and vision impairment. Effective models are essential for studying DK pathogenesis and evaluating potential therapeutic interventions. This study developed a novel biomimetic full-thickness corneal model for the first time,incorporating corneal epithelial cells,stromal cells,endothelial cells,and nerves to simulate DK conditions in vitro. By exposing the model to a high-glucose (HG) environment,the pathological characteristics of DK,including nerve bundle disintegration,compromised barrier integrity,increased inflammation,and oxidative stress,were successfully replicated. Transcriptomic analysis revealed that HG downregulated genes associated with axon and synapse formation while upregulating immune response and oxidative stress pathways,with C-C Motif Chemokine Ligand 5 (CCL5) identified as a key hub gene in DK pathogenesis. The therapeutic effects of Lycium barbarum glycopeptide (LBGP) were evaluated using this model and validated in db/db diabetic mice. LBGP promoted nerve regeneration,alleviated inflammation and oxidative stress in both in vitro and in vivo models. Notably,LBGP suppressed the expression of CCL5,highlighting its potential mechanism of action. This study establishes a robust biomimetic platform for investigating DK and other corneal diseases,and identifies LBGP as a promising therapeutic candidate for DK. These findings provide valuable insights into corneal disease mechanisms and pave the way for future translational research and clinical applications. Graphical abstractImage 1 Highlights•A full-thickness biomimetic corneal model containing corneal epithelium,nerves,stroma,and endothelium was constructed.•Using this model,the pathological characteristics of diabetic keratopathy were successfully replicated in vitro.•Lycium barbarum glycopeptide (LBGP) alleviated high-glucose-induced damage in vitro and in vivo models.•CCL5 plays an important role in the pathogenesis of diabetic keratopathy. View Publication

BackgroundTrichloroethylene (TCE) is a ubiquitous pollutant with potential capacity to induce congenital heart disease (CHD). However,the mechanisms underlying TCE-induced CHD are largely unraveled.MethodsWe exposed zebrafish embryos to TCE to investigate its cardiac development toxicity and related response factor through bulk RNA sequencing. We constructed transgenic fluorescent fish and employed the CRISPR/dCas9 system along with single-cell RNA sequencing to identify the genetic cause of TCE-induced CHD.ResultsWe found that early-stage exposure to TCE induced significant cardiac defects characterized by elongated SV-BA distance,thinned myocardium,and attenuated contractility. Gremlin1 encoding gene,grem1a,a putative target showing high expression at the beginning of cardiac development,was sharply down-regulated by TCE. Consistently,grem1a knockdown in zebrafish induced cardiac phenotypes generally like those of the TCE-treated group,accompanying the disarrangement of myofibril structure. Single-cell RNA-seq depicted that mitochondrial respiration in grem1a-repressed cardiomyocytes was greatly enhanced,ultimately leading to a branch from the normal trajectory of myocardial development. Accordingly,in vitro results demonstrated that GREM1 repression increased mitochondrial content,ATP production,mitochondrial reactive oxygen species,mitochondrial membrane potential,and disrupted myofibril expansion in hPSC-CMs.ConclusionsThese results suggested that TCE-induced gremlin1 repression could result in mitochondrial hyperfunction,thereby hampering cardiomyocyte development and causing cardiac defects in zebrafish embryos. This study not only provided a novel insight into the etiology for environmental stressor-caused cardiac development defects,but also offered a potential therapeutic and preventive target for TCE-induced CHD.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12964-025-02314-9. View Publication

Organoids,derived from human induced pluripotent stem cells (hiPSCs),are intricate three-dimensional in vitro structures that mimic many key aspects of the complex morphology and functions of in vivo organs such as the retina and heart. Traditional histological methods,while crucial,often fall short in analyzing these dynamic structures due to their inherently static and destructive nature. In this study,we leveraged the capabilities of optical coherence tomography (OCT) for rapid,non-invasive imaging of both retinal,cerebral,and cardiac organoids. Complementing this,we developed a sophisticated deep learning approach to automatically segment the organoid tissues and their internal structures,such as hollows and chambers. Utilizing this advanced imaging and analysis platform,we quantitatively assessed critical parameters,including size,area,volume,and cardiac beating,offering a comprehensive live characterization and classification of the organoids. These findings provide profound insights into the differentiation and developmental processes of organoids,positioning quantitative OCT imaging as a potentially transformative tool for future organoid research. View Publication

PurposeDilated cardiomyopathy (DCM) is a prevalent form of heart failure with limited therapeutic options. This study explores a novel treatment strategy involving the delivery of exosome-derived miRNA-185-5p inhibitors encapsulated in liposomes,aiming to target cardiac tissue and alleviate myocardial apoptosis and cuproptosis in DCM.MethodsThe miRNA-185-5p inhibitor,identified in our previous study and extracted from exosomes,was encapsulated in liposomes functionalized with a cardiac-targeting peptide. This system was used in both in vitro and in vivo models of DCM induced by doxorubicin (DOX). We evaluated the effects of this treatment on cardiac function,apoptosis,cuproptosis,oxidative stress,and fibrosis using echocardiography,histological analysis,Western blotting,and biochemical assays.ResultsIn vitro experiments demonstrated that the Lipo@miR-185-5p inhibitor markedly attenuated apoptosis and cuproptosis in H9C2 cells and iPSC-derived cardiomyocytes,with a 42.6% reduction in apoptotic cell rates and over 50% downregulation of cuproptosis-related markers (both P < 0.01). In vivo,the targeted liposomal formulation significantly improved cardiac function in DOX-induced DCM mice,as evidenced by a 27.3% increase in left ventricular ejection fraction (LVEF) and a 36.5% reduction in myocardial fibrosis area (P < 0.01),along with enhanced survival. These findings underscore the therapeutic potential of this targeted delivery strategy for the treatment of dilated cardiomyopathy.ConclusionLipo@miR-185-5p inhibitor,utilizing exosome-derived miRNA and targeted liposomal delivery,effectively alleviates DCM-induced myocardial dysfunction. This approach represents a promising therapeutic strategy for cardiovascular diseases by targeting specific molecular mechanisms involved in heart failure. View Publication