技术资料

Intervertebral disc disease (IDD) is a debilitating spine condition that can be caused by intervertebral disc (IVD) damage which progresses towards IVD degeneration and dysfunction. Recently,human pluripotent stem cells (hPSCs) were recognized as a valuable resource for cell-based regenerative medicine in skeletal diseases. Therefore,adult somatic cells reprogrammed into human induced pluripotent stem cells (hiPSCs) represent an attractive cell source for the derivation of notochordal-like cells (NCs) as a first step towards the development of a regenerative therapy for IDD. Utilizing a differentiation method involving treatment with a four-factor cocktail targeting the BMP,FGF,retinoic acid,and Wnt signaling pathways,we differentiate CRISPR/Cas9-generated mCherry-reporter knock-in hiPSCs into notochordal-like cells. Comprehensive analysis of transcriptomic changes throughout the differentiation process identified regulation of histone methylation as a pivotal driver facilitating the differentiation of hiPSCs into notochordal-like cells. We further provide evidence that specific inhibition of histone demethylases KDM2A and KDM7A/B enhanced the lineage commitment of hiPSCs towards notochordal-like cells. Our results suggest that inhibition of KDMs could be leveraged to alter the epigenetic landscape of hiPSCs to control notochord-specific gene expression. Thus,our study highlights the importance of epigenetic regulators in stem cell-based regenerative approaches for the treatment of disc degeneration. View Publication

Monocytes,the circulating macrophage precursors,contribute to diseases like atherosclerosis and asthma. Long non-coding RNAs (lncRNAs) have been shown to modulate the phenotype and inflammatory capacity of monocytes. We previously discovered the lncRNA SMANTIS,which contributes to cellular phenotype expression by controlling BRG1 in mesenchymal cells. Here,we report that SMANTIS is particularly highly expressed in monocytes and lost during differentiation into macrophages. Moreover,different types of myeloid leukemia presented specific SMANTIS expression patterns. Interaction studies revealed that SMANTIS binds RUNX1,a transcription factor frequently mutated in AML,primarily through its Alu-element on the RUNT domain. RNA-seq after CRISPR/Cas9-mediated deletion of SMANTIS or RUNX1 revealed an association with cell adhesion and both limited the monocyte adhesion to endothelial cells. Mechanistically,SMANTIS KO reduced RUNX1 genomic binding and altered the interaction of RUNX1 with EP300 and CBFB. Collectively,SMANTIS interacts with RUNX1 and attenuates monocyte adhesion,which might limit monocyte vascular egress. Subject terms: Long non-coding RNAs,Transcription View Publication

Despite their role as innate sentinels,macrophages can serve as cellular reservoirs of chikungunya virus (CHIKV),a highly-pathogenic arthropod-borne alphavirus that has caused large outbreaks among human populations. Here,with the use of viral chimeras and evolutionary selection analysis,we define CHIKV glycoproteins E1 and E2 as critical for virion production in THP-1 derived human macrophages. Through proteomic analysis and functional validation,we further identify signal peptidase complex subunit 3 (SPCS3) and eukaryotic translation initiation factor 3 subunit K (eIF3k) as E1-binding host proteins with anti-CHIKV activities. We find that E1 residue V220,which has undergone positive selection,is indispensable for CHIKV production in macrophages,as its mutation attenuates E1 interaction with the host restriction factors SPCS3 and eIF3k. Finally,we show that the antiviral activity of eIF3k is translation-independent,and that CHIKV infection promotes eIF3k translocation from the nucleus to the cytoplasm,where it associates with SPCS3. These functions of CHIKV glycoproteins late in the viral life cycle provide a new example of an intracellular evolutionary arms race with host restriction factors,as well as potential targets for therapeutic intervention. View Publication

The roles of the transcriptional factor SIX2 have been identified in several tumors. However,its roles in gastric cancer (GC) progression have not yet been revealed. Our objective is to explore the impact and underlying mechanisms of SIX2 on the stemness of GC cells. Lentivirus infection was employed to establish stable expression SIX2 or PFN2 in GC cells. Gain- and loss-of-function experiments were conducted to detect changes of stemness markers,flow cytometry profiles,tumor spheroid formation,and tumor-initiating ability. ChIP,RNA-sequencing,tissue microarray,and bioinformatics analysis were performed to reveal the correlation between SIX2 and PFN2. The mechanisms underlying the SIX2/PFN2 loop-mediated effects were elucidated through tissue microarray analysis,RNA stability assay,IP-MS,Co-Immunoprecipitation,and inhibition of the JNK signaling pathway. The stemness of GC cells was enhanced by SIX2. Mechanistically,SIX2 directly bound to PFN2’s promoter and promoted PFN2 activity. PFN2,in turn,promoted the mRNA stability of SIX2 by recruiting RNA binding protein YBX-1,subsequently activating the downstream MAPK/JNK pathway. This study unveils the roles of SIX2 in governing GC cell stemness,defining a novel SIX2/PFN2 regulatory loop responsible for this regulation. This suggests the potential of targeting the SIX2/PFN2 loop for GC treatment (Graphical Abstracts). The online version contains supplementary material available at 10.1186/s12967-024-05618-5. View Publication

Dimethylsulfoxide (DMSO) has conventionally been used for cell cryopreservation both in research and in clinical applications,but has long-term cytotoxic effects. Trehalose,a natural disaccharide,has been proposed as a non-toxic cryoprotectant. However,the lack of specific cell membrane transporter receptors inhibits transmembrane transport and severely limits its cryoprotective capability. This research presents a method to successfully deliver trehalose into mesenchymal stem cells (MSCs) using ultrasound in the presence of microbubbles. The optimised trehalose concentration was shown to be able to not only preserve membrane integrity and cell viability but also the multipotency of MSCs,which are essential for stem cell therapy. Confocal imaging revealed that rhodamine-labelled trehalose was transported into cells rather than simply attached to the membrane. Additionally,the membranes were successfully preserved in lyophilised cells. This study demonstrates that ultrasonication with microbubbles facilitated trehalose delivery,offering promising cryoprotective capability without the cytotoxicity associated with DMSO-based methods. Subject terms: Membrane biophysics,Biomedical engineering View Publication

Rhodiola species have been utilized as functional foods in Asia and Europe for promoting health. Research has demonstrated that Rhodiola has the potential to alleviate inflammatory bowel disease (IBD) in animal models. However,the specific active components and the underlying mechanism for ameliorating intestinal damage remain unclear. This study aims to explore the relieving effect of Rosavin (Rov),a known active constituent of Rhodiola,in IBD and the regulatory mechanisms. The therapeutic effect of Rov was evaluated using a murine model of acute colitis induced by dextran sulfate sodium salt (DSS). Inflammatory cytokines and neutrophil activation markers were measured by corresponding kits. Immunohistochemistry,immunofluorescence,TUNEL,and EdU assays were applied to investigate the tight conjunction proteins expression,epithelial marker expression,number of apoptotic cells,and epithelial proliferation,respectively. The protection effect of Rov on gut epithelial injury was assessed using TNF-α-induced intestinal organoids. Additinally,RNA sequencing was applied to observe the genetic alteration profile in these intestinal organoids. Oral administration of Rov significantly attenuated weight loss and restored colon length in mice. Notably,Rov treatment led to decreased levels of pro-inflammatory cytokines and neutrophil activation markers while increasing anti-inflammatory factors. Importantly,Rov restored intestinal despair by increasing the number of Lgr5 + stem cells,Lyz1 + Paneth cells and Muc2 + goblet cells in intestines of colitis mice,displaying reduced epithelial apoptosis and recovered barrier function. In TNF-α-induced intestinal organoids,Rov facilitated epithelial cell differentiation and protected against TNF-α-induced damage. RNA sequencing revealed upregulation in the gene expression associated with epithelial cells (including Lgr5 +,Lyz1 + and Muc2 + cells) proliferation and defensin secretion,unveiling the protective mechanisms of Rov on the intestinal epithelial barrier. Rov holds potential as a natural prophylactic agent against IBD,with its protective action on the intestinal epithelium being crucial for its therapeutic efficacy. View Publication

Immune checkpoint blockade (ICB) has made remarkable achievements,but newly identified armored and cold tumors cannot respond to ICB therapy. The high prevalence of concomitant medications has huge impact on immunotherapeutic responses,but the clinical effects on the therapeutic outcome of armored and cold tumors are still unclear. In this research,using large-scale transcriptomics datasets,the expression and potential biological functions of angiotensin II receptor 1 (AGTR1),the target of angiotensin receptor blocker (ARB),were investigated. Next,the roles of ARB in tumor cells and tumor microenvironment cells were defined by a series of in vitro and in vivo assays. In addition,the clinical impacts of ARB on ICB therapy were assessed by multicenter cohorts and meta-analysis. AGTR1 was overexpressed in armored and cold tumors and associated with poor response to ICB therapy. ARB,the inhibitor for AGTR1,only suppressed the aggressiveness of tumor cells with high AGTR1 expression,which accounted for a very small proportion. Further analysis revealed that AGTR1 was always highly expressed in cancer-associated fibroblasts (CAFs) and ARB inhibited type I collagen expression in CAFs by suppressing the RhoA-YAP axis. Moreover,ARB could also drastically reverse the phenotype of armored and cold to soft and hot in vivo,leading to a higher response to ICB therapy. In addition,both our in-house cohorts and meta-analysis further supported the idea that ARB can significantly enhance ICB efficacy. Overall,we identify AGTR1 as a novel target in armored and cold tumors and demonstrate the improved therapeutic efficacy of ICB in combination with ARB. These findings could provide novel clinical insight into how to treat patients with refractory armored and cold tumors. View Publication

Intrahepatic cholangiocarcinoma (iCCA) is a lethal primary liver tumor characterized by clinical aggressiveness,poor prognosis,and scarce therapeutic possibilities. Therefore,new treatments are urgently needed to render this disease curable. Since cumulating evidence supports the oncogenic properties of the Heat Shock Factor 1 (HSF1) transcription factor in various cancer types,we investigated its pathogenetic and therapeutic relevance in iCCA. Levels of HSF1 were evaluated in a vast collection of iCCA specimens. The effects of HSF1 inactivation on iCCA development in vivo were investigated using three established oncogene-driven iCCA mouse models. In addition,the impact of HSF1 suppression on tumor cells and tumor stroma was assessed in iCCA cell lines,human iCCA cancer-associated fibroblasts (hCAFs),and patient-derived organoids. Human preinvasive,invasive,and metastatic iCCAs displayed widespread HSF1 upregulation,which was associated with a dismal prognosis of the patients. In addition,hydrodynamic injection of a dominant-negative form of HSF1 (HSF1dn),which suppresses HSF1 activity,significantly delayed cholangiocarcinogenesis in AKT/NICD,AKT/YAP,and AKT/TAZ mice. In iCCA cell lines,iCCA hCAFs,and patient-derived organoids,administration of the HSF1 inhibitor KRIBB-11 significantly reduced proliferation and induced apoptosis. Cell death was profoundly augmented by concomitant administration of the Bcl-xL/Bcl2/Bcl-w inhibitor ABT-263. Furthermore,KRIBB-11 reduced mitochondrial bioenergetics and glycolysis of iCCA cells. The present data underscore the critical pathogenetic,prognostic,and therapeutic role of HSF1 in cholangiocarcinogenesis. The online version contains supplementary material available at 10.1186/s13046-024-03177-7. View Publication

Reduction of adult hippocampal neurogenesis is an early critical event in Alzheimer’s disease (AD),contributing to progressive memory loss and cognitive decline. Reduced levels of the nucleoporin 153 (Nup153),a key epigenetic regulator of NSC stemness,characterize the neural stem cells isolated from a mouse model of AD (3×Tg) (AD-NSCs) and determine their altered plasticity and gene expression. Nup153-regulated mechanisms contributing to NSC function were investigated: (1) in cultured NSCs isolated from AD and wild type (WT) mice by proteomics; (2) in vivo by lentiviral-mediated delivery of Nup153 or GFP in the hippocampus of AD and control mice analyzing neurogenesis and cognitive function; (3) in human iPSC-derived brain organoids obtained from AD patients and control subjects as a model of neurodevelopment. Proteomic approach identified Nup153 interactors in WT- and AD-NSCs potentially implicated in neurogenesis regulation. Gene ontology (GO) analysis showed that Nup153-bound proteins in WT-NSCs were involved in RNA metabolism,nuclear import and epigenetic mechanisms. Nup153-bound proteins in AD-NSCs were involved in pathways of neurodegeneration,mitochondrial dysfunction,proteasomal processing and RNA degradation. Furthermore,recovery of Nup153 levels in AD-NSCs reduced the levels of oxidative stress markers and recovered proteasomal activity. Lentiviral-mediated delivery of Nup153 in the hippocampal niche of AD mice increased the proliferation of early progenitors,marked by BrdU/DCX and BrdU/PSANCAM positivity and,later,the integration of differentiating neurons in the cell granule layer (BrdU/NeuN + cells) compared with GFP-injected AD mice. Consistently,Nup153-injected AD mice showed an improvement of cognitive performance in comparison to AD-GFP mice at 1 month after virus delivery assessed by Morris Water Maze. To validate the role of Nup153 in neurogenesis we took advantage of brain organoids derived from AD-iPSCs characterized by fewer neuroepithelial progenitor loops and reduced differentiation areas. The upregulation of Nup153 in AD organoids recovered the formation of neural-like tubes and differentiation. Our data suggest that the positive effect of Nup153 on neurogenesis is based on a complex regulatory network orchestrated by Nup153 and that this protein is a valuable disease target. The online version contains supplementary material available at 10.1186/s13287-024-03805-1. View Publication

Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease leading to motor neuron loss. Currently mutations in > 40 genes have been linked to ALS,but the contribution of many genes and genetic mutations to the ALS pathogenic process remains poorly understood. Therefore,we first performed comparative interactome analyses of five recently discovered ALS-associated proteins (C21ORF2,KIF5A,NEK1,TBK1,and TUBA4A) which highlighted many novel binding partners,and both unique and shared interactors. The analysis further identified C21ORF2 as a strongly connected protein. The role of C21ORF2 in neurons and in the nervous system,and of ALS-associated C21ORF2 variants is largely unknown. Therefore,we combined human iPSC-derived motor neurons with other models and different molecular cell biological approaches to characterize the potential pathogenic effects of C21ORF2 mutations in ALS. First,our data show C21ORF2 expression in ALS-relevant mouse and human neurons,such as spinal and cortical motor neurons. Further,the prominent ALS-associated variant C21ORF2-V58L caused increased apoptosis in mouse neurons and movement defects in zebrafish embryos. iPSC-derived motor neurons from C21ORF2-V58L-ALS patients,but not isogenic controls,show increased apoptosis,and changes in DNA damage response,mitochondria and neuronal excitability. In addition,C21ORF2-V58L induced post-transcriptional downregulation of NEK1,an ALS-associated protein implicated in apoptosis and DDR. In all,our study defines the pathogenic molecular and cellular effects of ALS-associated C21ORF2 mutations and implicates impaired post-transcriptional regulation of NEK1 downstream of mutant C21ORF72 in ALS. The online version contains supplementary material available at 10.1186/s40478-024-01852-6. View Publication

Recent advances in imaging suggested that spatial organization of hematopoietic cells in their bone marrow microenvironment (niche) regulates cell expansion,governing progression,and leukemic transformation of hematological clonal disorders. However,our ability to interrogate the niche in pre-malignant conditions has been limited,as standard murine models of these diseases rely largely on transplantation of the mutant clones into conditioned mice where the marrow microenvironment is compromised. Here,we leveraged live-animal microscopy and ultralow dose whole body or focal irradiation to capture single cells and early expansion of benign/pre-malignant clones in the functionally preserved microenvironment. 0.5 Gy whole body irradiation (WBI) allowed steady engraftment of cells beyond 30 weeks compared to non-conditioned controls. In-vivo tracking and functional analyses of the microenvironment showed no change in vessel integrity,cell viability,and HSC-supportive functions of the stromal cells,suggesting minimal inflammation after the radiation insult. The approach enabled in vivo imaging of Tet2 + /− and its healthy counterpart,showing preferential localization within a shared microenvironment while forming discrete micro-niches. Notably,stationary association with the niche only occurred in a subset of cells and would not be identified without live imaging. This strategy may be broadly applied to study clonal disorders in a spatial context. View Publication

Astrocytes are essential for the formation and maintenance of neural networks. However,a major technical challenge for investigating astrocyte function and disease-related pathophysiology has been the limited ability to obtain functional human astrocytes. Despite recent advances in human pluripotent stem cell (hPSC) techniques,primary rodent astrocytes remain the gold standard in coculture with human neurons. We demonstrate that a combination of leukemia inhibitory factor (LIF) and bone morphogenetic protein-4 (BMP4) directs hPSC-derived neural precursor cells to a highly pure population of astroglia in 28 d. Using single-cell RNA sequencing,we confirm the astroglial identity of these cells and highlight profound transcriptional adaptations in cocultured hPSC-derived astrocytes and neurons,consistent with their further maturation. In coculture with human neurons,multielectrode array recordings revealed robust network activity of human neurons in a coculture with hPSC-derived or rat astrocytes [3.63 ± 0.44 min −1 (hPSC-derived),2.86 ± 0.64 min −1 (rat); p = 0.19]. In comparison,we found increased spike frequency within network bursts of human neurons cocultured with hPSC-derived astrocytes [56.31 ± 8.56 Hz (hPSC-derived),24.77 ± 4.04 Hz (rat); p < 0.01],and whole-cell patch-clamp recordings revealed an increase of postsynaptic currents [2.76 ± 0.39 Hz (hPSC-derived),1.07 ± 0.14 Hz (rat); p < 0.001],consistent with a corresponding increase in synapse density [14.90 ± 1.27/100 μm 2 (hPSC-derived),8.39 ± 0.63/100 μm 2 (rat); p < 0.001]. Taken together,we show that hPSC-derived astrocytes compare favorably with rat astrocytes in supporting human neural network activity and maturation,providing a fully human platform for investigating astrocyte function and neuronal-glial interactions. View Publication