技术资料

Rett syndrome (RTT) is a severe neurodevelopmental disorder primarily caused by loss-of-function mutations in the MECP2 gene,resulting in diverse cellular dysfunctions. Here,we investigated the role of the long noncoding RNA (lncRNA) NEAT1 in the context of MeCP2 deficiency using human neural cells and RTT patient samples. Through single-cell RNA sequencing and molecular analyses,we found that NEAT1 is markedly downregulated in MECP2 knockout (KO) cells at various stages of neural differentiation. NEAT1 downregulation correlated with aberrant activation of the mTOR pathway,abnormal protein metabolism,and dysregulated autophagy,contributing to the accumulation of protein aggregates and impaired mitochondrial function. Reactivation of NEAT1 in MECP2-KO cells rescued these phenotypes,indicating its critical role downstream of MECP2. Furthermore,direct RNA–RNA interaction was revealed as the key process for NEAT1 influence on autophagy genes,leading to altered subcellular localization of specific autophagy-related messenger RNAs and impaired biogenesis of autophagic complexes. Importantly,NEAT1 restoration rescued the morphological defects observed in MECP2-KO neurons,highlighting its crucial role in neuronal maturation. Overall,our findings elucidate lncRNA NEAT1 as a key mediator of MeCP2 function,regulating essential pathways involved in protein metabolism,autophagy,and neuronal morphology. View Publication

Background: Human pluripotent stem cells (hPSCs),including human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs),can undergo erythroid differentiation,offering a potentially invaluable resource for generating large quantities of erythroid cells. However,the majority of erythrocytes derived from hPSCs fail to enucleate compared with those derived from cord blood progenitors,with an unknown molecular basis for this difference. The expression of vimentin (VIM) is retained in erythroid cells differentiated from hPSCs but is absent in mature erythrocytes. Further exploration is required to ascertain whether VIM plays a critical role in enucleation and to elucidate the underlying mechanisms. Methods: In this study,we established a hESC line with reversible vimentin degradation (dTAG-VIM-H9) using the proteolysis-targeting chimera (PROTAC) platform. Various time-course studies,including erythropoiesis from CD34+ human umbilical cord blood and three-dimensional (3D) organoid culture from hESCs,morphological analysis,quantitative real-time PCR (qRT-PCR),western blotting,flow cytometry,karyotyping,cytospin,Benzidine-Giemsa staining,immunofluorescence assay,and high-speed cell imaging analysis,were conducted to examine and compare the characteristics of hESCs and those with vimentin degradation,as well as their differentiated erythroid cells. Results: Vimentin expression diminished during normal erythropoiesis in CD34+ cord blood cells,whereas it persisted in erythroid cells differentiated from hESC. Depletion of vimentin using the degradation tag (dTAG) system promotes erythroid enucleation in dTAG-VIM-H9 cells. Nuclear polarization of erythroblasts is elevated by elimination of vimentin. Conclusions: VIM disappear during the normal maturation of erythroid cells,whereas they are retained in erythroid cells differentiated from hPSCs. We found that retention of vimentin during erythropoiesis impairs erythroid enucleation from hPSCs. Using the PROTAC platform,we validated that vimentin degradation by dTAG accelerates the enucleation rate in dTAG-VIM-H9 cells by enhancing nuclear polarization. View Publication

Hydrogen Peroxide (H2O2) is a central oxidant in redox biology due to its pleiotropic role in physiology and pathology. However,real-time monitoring of H2O2 in living cells and tissues remains a challenge. We address this gap with the development of an optogenetic hydRogen perOxide Sensor (oROS),leveraging the bacterial peroxide binding domain OxyR. Previously engineered OxyR-based fluorescent peroxide sensors lack the necessary sensitivity and response speed for effective real-time monitoring. By structurally redesigning the fusion of Escherichia coli (E. coli) ecOxyR with a circularly permutated green fluorescent protein (cpGFP),we created a novel,green-fluorescent peroxide sensor oROS-G. oROS-G exhibits high sensitivity and fast on-and-off kinetics,ideal for monitoring intracellular H2O2 dynamics. We successfully tracked real-time transient and steady-state H2O2 levels in diverse biological systems,including human stem cell-derived neurons and cardiomyocytes,primary neurons and astrocytes,and mouse brain ex vivo and in vivo. These applications demonstrate oROS’s capabilities to monitor H2O2 as a secondary response to pharmacologically induced oxidative stress and when adapting to varying metabolic stress. We showcased the increased oxidative stress in astrocytes via A?-putriscine-MAOB axis,highlighting the sensor’s relevance in validating neurodegenerative disease models. Lastly,we demonstrated acute opioid-induced generation of H2O2 signal in vivo which highlights redox-based mechanisms of GPCR regulation. oROS is a versatile tool,offering a window into the dynamic landscape of H2O2 signaling. This advancement paves the way for a deeper understanding of redox physiology,with significant implications for understanding diseases associated with oxidative stress,such as cancer,neurodegenerative,and cardiovascular diseases. View Publication

To facilitate the characterization of unlabeled induced pluripotent stem cells (iPSCs) during culture and expansion,we developed an AI pipeline for nuclear segmentation and mitosis detection from phase contrast images of individual cells within iPSC colonies. The analysis uses a 2D convolutional neural network (U-Net) plus a 3D U-Net applied on time lapse images to detect and segment nuclei,mitotic events,and daughter nuclei to enable tracking of large numbers of individual cells over long times in culture. The analysis uses fluorescence data to train models for segmenting nuclei in phase contrast images. The use of classical image processing routines to segment fluorescent nuclei precludes the need for manual annotation. We optimize and evaluate the accuracy of automated annotation to assure the reliability of the training. The model is generalizable in that it performs well on different datasets with an average F1 score of 0.94,on cells at different densities,and on cells from different pluripotent cell lines. The method allows us to assess,in a non-invasive manner,rates of mitosis and cell division which serve as indicators of cell state and cell health. We assess these parameters in up to hundreds of thousands of cells in culture for more than 36 hours,at different locations in the colonies,and as a function of excitation light exposure. View Publication

BackgroundTimely resolution of innate immune responses activated by surgical intervention is crucial for patient recovery. While cytokines and innate immune cells are critical in inflammation resolution,the specific role of IL-18 in these processes remains controversial and underexplored.MethodsWe investigate determinants of successful recovery using peripheral blood samples from orthopedic surgery (ORT) patients (n?=?33) at T0 (before surgery),T1 (24 h after surgery) and T2 (3 days after surgery). Monocytes from ORT patients underwent immunophenotyping together with bulk transcriptomic analysis. We found that IL-18 strongly defines the recovery immune signature. These results were further validated in vitro by comparing IL-18 and TNF-? effects on monocytes,and in 3D human intestine organoids together with single cell (sc)-RNAseq analysis.ResultsTranscriptomics of ORT monocytes revealed upregulation of ITG family integrins,namely ITGB3 and ITGB5,CXCL family chemokines,notably CXCL1-3,CXCL5,and SCL/TAL1 factor controlling differentiation and migration,but not pro-inflammatory genes. Similar changes were observed in IL-18 stimulated healthy donor monocytes in vitro,including an increase in CD11b,CD64,and CD86 levels,accompanied by increased phosphorylation of Akt but not NF?B. These changes were attenuated in the presence of TNF-?,thus showing a unique role of IL-18 when acting alone without its most frequent paired cytokine TNF-?. We further confirmed that IL-18 induces monocyte-macrophage transition and migration using human intestinal organoids. Finally,TNF-?/IL-18 ratio showed a high predictive value of clinical severity in septic patients.ConclusionsWe propose a novel role of IL-18 on monocyte migration and macrophage transition characterizing successful orthopedic surgery recovery,as well as the ratio of IL-18/TNF-? as a novel marker of inflammation resolution,with potential implications for patient monitoring and therapeutic strategies.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12967-025-06652-7. View Publication

Parkinson’s disease (PD) is a debilitating neurodegenerative disease characterized by the loss of midbrain dopaminergic neurons (DaNs) and the abnormal accumulation of ?-Synuclein (?-Syn) protein. Currently,no treatment can slow nor halt the progression of PD. Multiplications and mutations of the ?-Syn gene (SNCA) cause PD-associated syndromes and animal models that overexpress ?-Syn replicate several features of PD. Decreasing total ?-Syn levels,therefore,is an attractive approach to slow down neurodegeneration in patients with synucleinopathy. We previously performed a genetic screen for modifiers of ?-Syn levels and identified CDK14,a kinase of largely unknown function as a regulator of ?-Syn. To test the potential therapeutic effects of CDK14 reduction in PD,we ablated Cdk14 in the ?-Syn preformed fibrils (PFF)-induced PD mouse model. We found that loss of Cdk14 mitigates the grip strength deficit of PFF-treated mice and ameliorates PFF-induced cortical ?-Syn pathology,indicated by reduced numbers of pS129 ?-Syn-containing cells. In primary neurons,we found that Cdk14 depletion protects against the propagation of toxic ?-Syn species. We further validated these findings on pS129 ?-Syn levels in PD patient neurons. Finally,we leveraged the recent discovery of a covalent inhibitor of CDK14 to determine whether this target is pharmacologically tractable in vitro and in vivo. We found that CDK14 inhibition decreases total and pathologically aggregated ?-Syn in human neurons,in PFF-challenged rat neurons and in the brains of ?-Syn-humanized mice. In summary,we suggest that CDK14 represents a novel therapeutic target for PD-associated synucleinopathy. View Publication

BackgroundX-linked juvenile retinoschisis (XLRS) is an inherited disease caused by RS1 gene mutation,which leads to retinal splitting and visual impairment. The mechanism of RS1-associated retinal degeneration is not fully understood. Besides,animal models of XLRS have limitations in the study of XLRS. Here,we used human induced pluripotent stem cell (hiPSC)-derived retinal organoids (ROs) to investigate the disease mechanisms and potential treatments for XLRS.MethodshiPSCs reprogrammed from peripheral blood mononuclear cells of two RS1 mutant (E72K) XLRS patients were differentiated into ROs. Subsequently,we explored whether RS1 mutation could affect RO development and explore the effectiveness of RS1 gene augmentation therapy.ResultsROs derived from RS1 (E72K) mutation hiPSCs exhibited a developmental delay in the photoreceptor,retinoschisin (RS1) deficiency,and altered spontaneous activity compared with control ROs. Furthermore,the delays in development were associated with decreased expression of rod-specific precursor markers (NRL) and photoreceptor-specific markers (RCVRN). Adeno-associated virus (AAV)-mediated gene augmentation with RS1 at the photoreceptor immature stage rescued the rod photoreceptor developmental delay in ROs with the RS1 (E72K) mutation.ConclusionsThe RS1 (E72K) mutation results in the photoreceptor development delay in ROs and can be partially rescued by the RS1 gene augmentation therapy.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13287-024-03767-4. View Publication

The stimulator of interferon genes (STING) pathway has been implicated in neurodegenerative diseases,including Parkinson’s disease and amyotrophic lateral sclerosis (ALS). While prior studies have focused on STING within immune cells,little is known about STING within neurons. Here,we document neuronal activation of the STING pathway in human postmortem cortical and spinal motor neurons from individuals affected by familial or sporadic ALS. This process takes place selectively in the most vulnerable cortical and spinal motor neurons but not in neurons that are less affected by the disease. Concordant STING activation in layer V cortical motor neurons occurs in a mouse model of C9orf72 repeat-associated ALS and frontotemporal dementia (FTD). To establish that STING activation occurs in a neuron-autonomous manner,we demonstrate the integrity of the STING signaling pathway,including both upstream activators and downstream innate immune response effectors,in dissociated mouse cortical neurons and neurons derived from control human induced pluripotent stem cells (iPSCs). Human iPSC-derived neurons harboring different familial ALS-causing mutations exhibit increased STING signaling with DNA damage as a main driver. The elevated downstream inflammatory markers present in ALS iPSC-derived neurons can be suppressed with a STING inhibitor. Our results reveal an immunophenotype that consists of innate immune signaling driven by the STING pathway and occurs specifically within vulnerable neurons in ALS/FTD.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00401-024-02688-z. View Publication

Background & aimsHumans with WNT2B deficiency have severe intestinal disease,including significant inflammatory injury,highlighting a critical role for WNT2B. We sought to understand how WNT2B contributes to intestinal homeostasis.MethodsWe investigated the intestinal health of Wnt2b knock out (KO) mice. We assessed the baseline histology and health of the small intestine and colon,and the impact of inflammatory challenge using dextran sodium sulfate (DSS). We also evaluated human intestinal tissue.ResultsMice with WNT2B deficiency had normal baseline histology but enhanced susceptibility to DSS colitis because of an increased early injury response. Although intestinal stem cells markers were decreased,epithelial proliferation was similar to control subjects. Wnt2b KO mice showed an enhanced inflammatory signature after DSS treatment. Wnt2b KO colon and human WNT2B-deficient organoids had increased levels of CXCR4 and IL6,and biopsy tissue from humans showed increased neutrophils.ConclusionsWNT2B is important for regulation of inflammation in the intestine. Absence of WNT2B leads to increased expression of inflammatory cytokines and increased susceptibility to gastrointestinal inflammation,particularly in the colon. Graphical abstract View Publication

To comprehend the volumetric neural connectivity of a brain organoid,it is crucial to monitor the spatiotemporal electrophysiological signals within the organoid,known as intra-organoid signals. However,previous methods risked damaging the three-dimensional (3D) cytoarchitecture of organoids,either through sectioning or inserting rigid needle-like electrodes. Also,the limited numbers of electrodes in fixed positions with non-adjustable electrode shapes were insufficient for examining the complex neural activity throughout the organoid. Herein,we present a magnetically reshapable 3D multi-electrode array (MEA) using direct printing of liquid metals for electrophysiological analysis of brain organoids. The adaptable distribution and the softness of these printed electrodes facilitate the spatiotemporal recording of intra-organoid signals. Furthermore,the unique capability to reshape these soft electrodes within the organoid using magnetic fields allows a single electrode in the MEA to record from multiple points,effectively increasing the recording site density without the need for additional electrodes. Conventional platforms for electrophysiological recording of organoids have limited recording site density. Here,the authors present the magnetically reshapable 3D liquid metal-based electrode array for high-resolution analysis on neural activities of brain organoids. View Publication

SummaryEpigenetic dysregulation has emerged as an important etiological mechanism of neurodevelopmental disorders (NDDs). Pathogenic variation in epigenetic regulators can impair deposition of histone post-translational modifications leading to aberrant spatiotemporal gene expression during neurodevelopment. The male-specific lethal (MSL) complex is a prominent multi-subunit epigenetic regulator of gene expression and is responsible for histone 4 lysine 16 acetylation (H4K16ac). Using exome sequencing,here we identify a cohort of 25 individuals with heterozygous de novo variants in MSL complex member MSL2. MSL2 variants were associated with NDD phenotypes including global developmental delay,intellectual disability,hypotonia,and motor issues such as coordination problems,feeding difficulties,and gait disturbance. Dysmorphisms and behavioral and/or psychiatric conditions,including autism spectrum disorder,and to a lesser extent,seizures,connective tissue disease signs,sleep disturbance,vision problems,and other organ anomalies,were observed in affected individuals. As a molecular biomarker,a sensitive and specific DNA methylation episignature has been established. Induced pluripotent stem cells (iPSCs) derived from three members of our cohort exhibited reduced MSL2 levels. Remarkably,while NDD-associated variants in two other members of the MSL complex (MOF and MSL3) result in reduced H4K16ac,global H4K16ac levels are unchanged in iPSCs with MSL2 variants. Regardless,MSL2 variants altered the expression of MSL2 targets in iPSCs and upon their differentiation to early germ layers. Our study defines an MSL2-related disorder as an NDD with distinguishable clinical features,a specific blood DNA episignature,and a distinct,MSL2-specific molecular etiology compared to other MSL complex-related disorders. Graphical abstract MSL2 encodes a member of the MSL complex,an epigenetic regulator acetylating histone H4. We identify MSL2 variants leading to a neurodevelopmental disorder with intellectual disability,developmental delay,motor issues,seizures,dysmorphisms,and a specific blood methylation episignature. Patient-derived reprogrammed cells reveal developmental gene dysregulation without altered global H4 acetylation. View Publication

BackgroundAtrial fibrillation has an estimated prevalence of 1.5–2%,making it the most common cardiac arrhythmia. The processes that cause and sustain the disease are still not completely understood. An association between atrial fibrillation and systemic,as well as local,inflammatory processes has been reported. However,the exact mechanisms underlying this association have not been established. While it is understood that inflammatory macrophages can influence cardiac electrophysiology,a direct,causative relationship to atrial fibrillation has not been described. This study investigated the pro-arrhythmic effects of activated M1 macrophages on human induced pluripotent stem cell (hiPSC)-derived atrial cardiomyocytes,to propose a mechanistic link between inflammation and atrial fibrillation.MethodsTwo hiPSC lines from healthy individuals were differentiated to atrial cardiomyocytes and M1 macrophages and integrated in an isogenic,pacing-free,atrial fibrillation-like coculture model. Electrophysiology characteristics of cocultures were analysed for beat rate irregularity,electrogram amplitude and conduction velocity using multi electrode arrays. Cocultures were additionally treated using glucocorticoids to suppress M1 inflammation. Bulk RNA sequencing was performed on coculture-isolated atrial cardiomyocytes and compared to meta-analyses of atrial fibrillation patient transcriptomes.ResultsMulti electrode array recordings revealed M1 to cause irregular beating and reduced electrogram amplitude. Conduction analysis further showed significantly lowered conduction homogeneity in M1 cocultures. Transcriptome sequencing revealed reduced expression of key cardiac genes such as SCN5A,KCNA5,ATP1A1,and GJA5 in the atrial cardiomyocytes. Meta-analysis of atrial fibrillation patient transcriptomes showed high correlation to the in vitro model. Treatment of the coculture with glucocorticoids showed reversal of phenotypes,including reduced beat irregularity,improved conduction,and reversed RNA expression profiles.ConclusionsThis study establishes a causal relationship between M1 activation and the development of subsequent atrial arrhythmia,documented as irregularity in spontaneous electrical activation in atrial cardiomyocytes cocultured with activated macrophages. Further,beat rate irregularity could be alleviated using glucocorticoids. Overall,these results point at macrophage-mediated inflammation as a potential AF induction mechanism and offer new targets for therapeutic development. The findings strongly support the relevance of the proposed hiPSC-derived coculture model and present it as a first of its kind disease model.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13287-024-03814-0. View Publication