技术资料

Pancreatic islets are densely packed cellular aggregates containing various hormonal cell types essential for blood glucose regulation. Interactions among these cells markedly affect the glucoregulatory functions of islets along with the surrounding niche and pancreatic tissue-specific geometrical organization. However,stem cell (SC)-derived islets generated in vitro often lack the three-dimensional extracellular microenvironment and peri-vasculature,which leads to the immaturity of SC-derived islets,reducing their ability to detect glucose fluctuations and insulin release. Here,we bioengineer the in vivo-like pancreatic niches by optimizing the combination of pancreatic tissue-specific extracellular matrix and basement membrane proteins and utilizing bioprinting-based geometrical guidance to recreate the spatial pattern of islet peripheries. The bioprinted islet-specific niche promotes coordinated interactions between islets and vasculature,supporting structural and functional features resembling native islets. Our strategy not only improves SC-derived islet functionality but also offers significant potential for advancing research on islet development,maturation,and diabetic disease modeling,with future implications for translational applications. The glucoregulatory functions of pancreatic islets are affected by their surrounding niche and spatial organization. Here,bioengineered stem-cell derived islet niches use bioprinting-based geometrical guidance to promote islet maturation for improved functionality and diabetes research. View Publication

Spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant neurodegenerative disease caused by repeat expansion of the CAG trinucleotide within exon 10 of the ATXN3 gene. This mutation results in the production of an abnormal ataxin-3 protein containing an extended polyglutamine tract,referred to as mutant ataxin-3. In this study,we investigated the therapeutic potential of CRISPR/Cas9-mediated genome editing for SCA3. First,we designed a specific single-guide RNA targeting the ATXN3 gene and constructed the corresponding targeting vector. Induced pluripotent stem cells (iPSCs) derived from a SCA3 patient were then electroporated with the CRISPR/Cas9 components. Positive clones were screened and validated by PCR and Sanger sequencing to obtain genome-editing iPSCs (GE-iPSCs). Subsequently,the pluripotency of GE-iPSCs was confirmed,and the effects of genome editing on mutant ataxin-3 protein expression and Golgi apparatus morphology were assessed using Western blotting and immunofluorescence analyses. Our results demonstrated that targeted insertion of polyadenylation signals (PAS) upstream of the abnormal CAG repeats effectively suppressed the production of mutant ataxin-3. This intervention also reduced the formation of neuronal nuclear inclusions in differentiated neurons,restored the structural integrity of the Golgi apparatus (which exhibited a loose and enlarged morphology in SCA3 cells),and increased the expression levels of Golgi structural proteins (GM130 and GORASP2). In conclusion,our findings indicate that the targeted insertion of PAS upstream of the abnormal CAG repeats in the ATXN3 gene represents a promising therapeutic strategy for SCA3 through genome editing.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-93369-8. View Publication

SUMMARYUnderstanding how human gene expression is coordinately regulated by functional units of proteins across the genome remains a major biological goal. Here,we present COMET,a high-throughput screening platform for combinatorial effector targeting for the identification of transcriptional modulators. We generate libraries of combinatorial dCas9-based fusion proteins,containing two to six effector domains,allowing us to systematically investigate more than 110,000 combinations of effector proteins at endogenous human loci for their influence on transcription. Importantly,we keep full proteins or domains intact,maintaining catalytic cores and surfaces for protein-protein interactions. We observe more than 5800 significant hits that modulate transcription,we demonstrate cell type specific transcriptional modulation,and we further investigate epistatic relationships between our effector combinations. We validate unexpected combinations as synergistic or buffering,emphasizing COMET as both a method for transcriptional effector discovery,and as a functional genomics tool for identifying novel domain interactions and directing locus-specific biochemistry. View Publication

Ribosome profiling,which is based on deep sequencing of ribosome footprints,has served as a powerful tool for elucidating the regulatory mechanism of protein synthesis. However,the current method has substantial issues: contamination by rRNAs and the lack of appropriate methods to measure ribosome numbers in transcripts. Here,we overcome these hurdles through the development of “Ribo-FilterOut”,which is based on the separation of footprints from ribosome subunits by ultrafiltration,and “Ribo-Calibration”,which relies on external spike-ins of stoichiometrically defined mRNA-ribosome complexes. A combination of these approaches estimates the number of ribosomes on a transcript,the translation initiation rate,and the overall number of translation events before its decay,all in a genome-wide manner. Moreover,our method reveals the allocation of ribosomes under heat shock stress,during aging,and across cell types. Our strategy of modified ribosome profiling measures kinetic and stoichiometric parameters of cellular translation across the transcriptome. Ribosome profiling faces issues with rRNA contamination and measurements of ribosome numbers on transcripts. Here,the authors develop Ribo-FilterOut and Ribo-Calibration,methods which can be used to estimate kinetic and stoichiometric parameters of translation under various conditions. View Publication

BackgroundCHD7 encodes an ATP-dependent chromodomain helicase DNA binding protein; mutations in this gene lead to multiple developmental disorders,including CHARGE (Coloboma,Heart defects,Atresia of the choanae,Retardation of growth and development,Genital hypoplasia,and Ear anomalies) syndrome. How the mutations cause multiple defects remains largely unclear. Embryonic definitive endoderm (DE) generates the epithelial compartment of vital organs such as the thymus,liver,pancreas,and intestine.MethodsIn this study,we used the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technique to delete the CHD7 gene in human embryonic stem cells (hESCs) to generate CHD7 homozygous mutant (CHD7?/?),heterozygous mutant (CHD7+/?),and control wild-type (CHD7+/+) cells. We then investigated the ability of the hESCs to develop into DE and the other two germ layers,mesoderm and ectoderm in vitro. We also compared global gene expression and chromatin accessibility among the hESC-DE cells by RNA sequencing (RNA-seq) and the assay for transposase-accessible chromatin with sequencing (ATAC-seq).ResultsWe found that deletion of CHD7 led to reduced capacity to develop into DE and mesoderm in a dose-dependent manner. Loss of CHD7 led to significant changes in the expression and chromatin accessibility of genes associated with several pathways. We identified 40 genes that were highly down-regulated in both the expression and chromatin accessibility in CHD7 deleted hESC-DE cells.ConclusionsCHD7 is critical for DE and mesodermal development from hESCs. Our results provide new insights into the mechanisms by which CHD7 mutations cause multiple congenital anomalies.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13287-025-04437-9. View Publication

The spatial organization of molecules in a cell is essential for their functions. While current methods focus on discerning tissue architecture,cell–cell interactions,and spatial expression patterns,they are limited to the multicellular scale. We present Bento,a Python toolkit that takes advantage of single-molecule information to enable spatial analysis at the subcellular scale. Bento ingests molecular coordinates and segmentation boundaries to perform three analyses: defining subcellular domains,annotating localization patterns,and quantifying gene–gene colocalization. We demonstrate MERFISH,seqFISH +,Molecular Cartography,and Xenium datasets. Bento is part of the open-source Scverse ecosystem,enabling integration with other single-cell analysis tools.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13059-024-03217-7. View Publication

Huntington’s disease and other disorders of the basal ganglia create challenges for biomolecule-based medicines given the poor accessibility of these deep brain structures following intracerebral or intravascular delivery. Here,we found that low dose,low volume delivery of unbiased AAV libraries into the globus pallidus allowed recovery of novel capsids capable of broad access to key deep brain and cortical structures relevant for human therapies. One such capsid,AAV-DB-3,provided transduction of up to 45% of medium spiny neurons in the adult NHP striatum,along with substantial transduction of relevant deep layer neurons in the cortex. Notably,AAV-DB-3 behaved similarly in mice as in NHPs and potently transduced human neurons derived from induced pluripotent stem cells. Thus,AAV-DB-3 provides a unique AAV for network level brain gene therapies that translates up and down the evolutionary scale for preclinical studies and eventual clinical use. To date,brain gene therapies require high vector doses. Here,authors devised an AAV capsid screen and found variants with unprecedented potency for transduction of deep brain and cortical neurons and human iPSC-neurons with cell tropism relevant for Huntington’s and Parkinson’s disease. View Publication

AbstractBackgroundParkinson's disease (PD) is a chronic neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra,which promotes a sustained inflammatory environment in the central nervous system. Regulatory T cells (Tregs) play an important role in the control of inflammation and might play a neuroprotective role. Indeed,a decrease in Treg number and function has been reported in PD. In this context,pramipexole,a dopaminergic receptor agonist used to treat PD symptoms,has been shown to increase peripheral levels of Treg cells and improve their suppressive function. The aim of this work was to determine the effect of pramipexole on immunoregulatory Treg cells and its possible neuroprotective effect on human dopaminergic neurons differentiated from human embryonic stem cells.MethodsTreg cells were sorted from white blood cells of healthy human donors. Assays were performed with CD3/CD28?activated and non?activated Treg cells treated with pramipexole at concentrations of 2 or 200 ng/mL. These regulatory cells were co?cultured with in vitro?differentiated human dopaminergic neurons in a cytotoxicity assay with 6?hydroxydopamine (6?OHDA). The role of interleukin?10 (IL?10) was investigated by co?culturing activated IL?10?producing Treg cells with neurons. To further investigate the effect of treatment on Tregs,gene expression in pramipexole?treated,CD3/CD28?activated Treg cells was determined by Fluidigm analysis.ResultsPramipexole?treated CD3/CD28?activated Treg cells showed significant protective effects on dopaminergic neurons when challenged with 6?OHDA. Pramipexole?treated activated Treg cells showed neuroprotective capacity through mechanisms involving IL?10 release and the activation of genes associated with regulation and neuroprotection.ConclusionAnti?CD3/CD28?activated Treg cells protect dopaminergic neurons against 6?OHDA?induced damage. In addition,activated,IL?10?producing,pramipexole?treated Tregs also induced a neuroprotective effect,and the supernatants of these co?cultures promoted axonal growth. Pramipexole?treated,activated Tregs altered their gene expression in a concentration?dependent manner,and enhanced TGF??related dopamine receptor regulation and immune?related pathways. These findings open new perspectives for the development of immunomodulatory therapies for the treatment of PD. Pramipexole?treated,activated regulatory T cells protect dopaminergic neurons against 6 OHDA damage and promote primary neurite length. This could be due to the production of the regulatory cytokine IL?10 and an increased expression of genes related to regulation and neuroprotection. View Publication

BackgroundStem-cell-derived therapy is a promising option for tissue regeneration. Human iPSC-derived progenitors of smooth muscle cells (pSMCs) exhibit limited proliferation and differentiation,which minimizes the risk of tumor formation while restoring smooth muscle cells (SMCs). Up to 29% of women suffer from recurrence of vaginal prolapse after prolapse surgery. Therefore,there is a need for therapies that can restore vaginal function. SMCs contribute to vaginal tone and contractility. We sought to examine whether human pSMCs can restore vaginal function in a rat model.MethodsFemale immunocompromised RNU rats were divided into 5 groups: intact controls (n?=?12),VSHAM (surgery?+?saline injection,n?=?35),and three cell-injection groups (surgery?+?cell injection using pSMCs from three patients,n?=?14/cell line). The surgery to induce vaginal injury was analogous to prolapse surgery. Menopause was induced by surgical ovariectomy. The vagina,urethra,bladder were harvested 10 weeks after surgery (5 weeks after cell injection). Organ bath myography was performed to evaluate the contractile function of the vagina,and smooth muscle thickness was examined by tissue immunohistochemistry. Collagen I,collagen III,and elastin mRNA and protein expressions in tissues were assessed.ResultsVaginal smooth muscle contractions induced by carbachol and KCl in the cell-injection groups were significantly greater than those in the VSHAM group. Collagen I protein expression in the vagina of the cell-injections groups was significantly higher than in the VSHAM group. Vaginal elastin protein expression was similar between the cell-injection and VSHAM groups. In the urethra,gene expression levels of collagen I,III,and elastin were all significantly greater in the cell-injection groups than in the VSHAM group. Collagen I,III,and elastin protein expression of the urethra did not show a consistent trend between cell-injection groups and the VSHAM group.ConclusionsHuman iPSC-derived pSMCs transplantation appears to be associated with improved contractile function of the surgically injured vagina in a rat model. This is accompanied by changes in extracellular protein expression the vagina and urethra. These observations support further efforts in the translation of pSMCs into a treatment for regenerating the surgically injured vagina in women who suffer recurrent prolapse after surgery.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13287-024-03900-3. View Publication

The immune-modulatory effects of mesenchymal stromal cells (MSCs) are widely used to treat inflammatory disorders,with indoleamine 2,4-dioxygenase-1 (IDO-1) playing a pivotal role in suppressing stimulated T-cell proliferation. Taking that three-dimensional (3D) cultures enhance MSCs’ anti-inflammatory properties compared with two-dimensional (2D) cultures,the differentially expressed miRNAs were examined. Thus,we identified hsa-miR-4662a-5p (miR-4662a) as a key inducer of IDO-1 via its suppression of bridging integrator-1 (BIN-1),a negative regulator of the IDO-1 gene. The IDO-1-inducing potential of miR-4662a was conserved across primary MSCs from various donors and sources but exhibited variability. Notably,iPSC-derived MSCs (iMSCs) demonstrated superior IDO-1 induction and immune-modulatory efficacy compared with their donor-matched primary MSCs. Accordingly,iMSCs expressing miR-4662a (4662a/iMSC) exhibited stronger suppressive effects on T-cell proliferation and more potent suppressive effects on graft-versus-host disease (GVHD),improving survival rates and reducing tissue damage in the liver and gut. Our results point to the therapeutic potential of standardized,off-the-shelf 4662a/iMSC as a robust immune-modulating cell therapy for GVHD. View Publication

New approach methodologies (NAMs) for predicting embryotoxicity and developmental toxicity are urgently needed for generating human relevant data,while reducing turnover time and costs,and alleviating ethical concerns related to the use of animal models. We have previously developed the PluriLum assay,a NKX2.5-reporter gene 3D model using human-induced pluripotent stem cells (hiPSCs) that are genetically modified to enable the assessment of adverse effects of chemicals on the early-stage embryo. Aiming at improving the predictive value of the PluriLum assay for future screening purposes,we sought to introduce standardization steps to the protocol,improving the overall robustness of the PluriLum assay,as well as a shortening of the assay protocol. First,we showed that the initial size of embryoid bodies (EBs) is crucial for a proper differentiation into cardiomyocytes and overall reproducibility of the assay. When the starting diameter of the EBs exceeds 500 µm,robust differentiation can be anticipated. In terms of reproducibility,exposure to the fungicide epoxiconazole at smaller initial diameters resulted in a larger variation of the derived data,compared to more reliable concentration–response curves obtained using spheroids with larger initial diameters. We further investigated the ideal length of the differentiation protocol,resulting in a shortening of the PluriLum assay by 24 h to 7 days. Following exposure to the teratogens all-trans and 13-cis retinoic acid,both cardiomyocyte contraction and measurement of NKX2.5-derived luminescence were recorded with a similar or increased sensitivity after 6 days of differentiation when compared to the original 7 days. Finally,we have introduced an efficient step for enzymatic dissociation of the EBs at assay termination. This allows for an even splitting of the individual EBs and testing of additional endpoints other than the NKX2.5-luciferase reporter,which was demonstrated in this work by the simultaneous assessment of ATP levels. In conclusion,we have introduced standardizations and streamlined the PluriLum assay protocol to improve its suitability as a NAM for screening of a large number of chemicals for developmental toxicity testing. View Publication

Dystrophy-associated fer-1-like protein (dysferlin) conducts plasma membrane repair. Mutations in the DYSF gene cause a panoply of genetic muscular dystrophies. We targeted a frequent loss-of-function,DYSF exon 44,founder frameshift mutation with mRNA-mediated delivery of SpCas9 in combination with a mutation-specific sgRNA to primary muscle stem cells from two homozygous patients. We observed a consistent >60% exon 44 re-framing,rescuing a full-length and functional dysferlin protein. A new mouse model harboring a humanized Dysf exon 44 with the founder mutation,hEx44mut,recapitulates the patients’ phenotype and an identical re-framing outcome in primary muscle stem cells. Finally,gene-edited murine primary muscle stem-cells are able to regenerate muscle and rescue dysferlin when transplanted back into hEx44mut hosts. These findings are the first to show that a CRISPR-mediated therapy can ameliorate dysferlin deficiency. We suggest that gene-edited primary muscle stem cells could exhibit utility,not only in treating dysferlin deficiency syndromes,but also perhaps other forms of muscular dystrophy. Dysferlin-deficient muscular dystrophy is a devastating and untreatable disease. Using Cas9,the authors restored dysferlin in muscle stem cells from patients ex vivo and show proof-of-concept for autologous cell replacement therapies in a new humanized mouse model. View Publication