技术资料

The principal organization of mammalian neuromuscular junctions (NMJs) shares essential features across species. However,human NMJs (hNMJs) exhibit distinct structural and physiological properties. While recent advances in stem-cell-based systems have significantly improved in vitro modeling of hNMJs,the extent to which these models recapitulate in vivo development remains unclear. Here,we performed temporal transcriptomic analysis of human three-dimensional (3D) neuromuscular co-cultures,composed of iPSC-derived motoneurons and skeletal muscle engineered from primary myoblasts. We found that the expression pattern follows a temporally coordinated gene expression program underlying NMJ maturation. The model recapitulates transcriptional features of NMJ development,including early myoblast fusion and presynaptic development,followed by a late-stage upregulation of postsynaptic markers and embryonic AChR subunits. Importantly,comparable transcriptional dynamics across two independent hiPSC lines confirm the reproducibility and robustness of this system. This study confirms on a transcriptional level that human 3D neuromuscular co-cultures are a robust and physiologically relevant model for investigating hNMJ development and function. View Publication

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy with a poor prognosis and limited therapeutic options. Leukemic stem cells (LSCs),which drive disease progression and confer resistance to therapy,pose a significant challenge to conventional treatment strategies. In this study,we identified and characterized the inhibitory mechanisms of TH37,a small molecule derived from traditional Chinese medicine,which selectively targets AML blasts and LSCs. Our analyses identified peroxiredoxin 1 (PRDX1),an enzyme that catalyzes the breakdown of hydrogen peroxide (a reactive oxygen species),as the primary molecular target of TH37. We demonstrated that TH37 directly interacts with PRDX1,inhibiting its enzymatic activity and thereby elevating intracellular reactive oxygen species levels in AML cells. PRDX1 was found to be overexpressed in AML,and its expression correlated with poor prognosis and the activation of AML- and cancer-associated pathways. Targeting PRDX1,either through lentiviral short-hairpin RNA-mediated silencing or TH37 treatment,induced apoptosis,reduced colony formation,and impaired the engraftment and growth of AML cells in immunodeficient mouse models. Furthermore,TH37 synergized with conventional chemotherapeutic agent to significantly reduce the viability and colony-forming capacity of AML cells. These findings demonstrate the critical role of PRDX1 in AML pathogenesis and highlight its potential as a key therapeutic target to improve clinical outcomes for AML patients. View Publication

BackgroundHigh densities of tertiary lymphoid structures (TLSs) are associated with improved clinical outcomes in various malignancies,including human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC). However,the role of TLSs in shaping antitumor immunity in HPV-induced cervical cancer (CESC) remains unclear. Therefore,we analyzed the density,composition,and prognostic impact of TLSs in patients with CESC as well as patients with HNSCC.MethodsMultiplex immunofluorescence,immunohistochemistry,and spatial transcriptomics were used to analyze TLS density and composition in HNSCC and CESC tissue sections with respect to patient prognosis. The spatial approach was supplemented by flow cytometry-based analysis of the polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC) phenotype in freshly resected primary tumor tissues.ResultsAlthough both indications were associated with HPV infection,we confirmed a positive correlation between TLS density and improved overall survival only in patients with HNSCC. The TLS composition differed markedly between HNSCC and CESC samples,with a shift toward high regulatory T cell (Treg) and PMN-MDSC abundance in CESC samples. The highest Treg and PMN-MDSC levels were observed in patients with CESC who died of the disease. CESC-infiltrating PMN-MDSCs showed high arginase 1 expression,which correlated with diminished T-cell receptor (TCR)ζ chain expression in CESC-infiltrating T cells. Additionally,the high number of PMN-MDSCs in TLSs was associated with the absence of HPV-specific T cells in CESC.ConclusionsUnlike in HNSCC,the composition of TLSs,rather than their quantity,was associated with the overall survival of patients with CESC. High numbers of Tregs and PMN-MDSCs infiltrating immature TLSs prevail in patients with CESC who succumbed to the disease and seem to affect tumor-specific immune responses. View Publication

Primary human endothelial cells represent an essential tool to model endothelial dysfunction and to screen interventions for its treatment. Here,we developed a protocol for the synchronous isolation of primary human saphenous vein endothelial cells (HSaVEC),human internal thoracic artery endothelial cells (HITAEC),and human microvascular endothelial cells (HMVEC) from SV and ITA utilized as conduits during coronary artery bypass graft surgery and from subcutaneous adipose tissue excised while providing an access to the heart. Treatment by collagenase type IV and magnetic separation with anti-CD31-antibody-coated beads ensured relatively high efficiency of the isolation (≈60% for HSaVEC,≈50% for HITAEC,and ≈20% for HMVEC) and high purity (≥99%) of isolated ECs within ≈2 weeks (HSaVEC),≈2–3 weeks (HITAEC),and ≈3–4 weeks (HMVEC). A colorimetric assay of cell viability and proliferation,as well as real-time bioimpedance monitoring using the xCELLigence instrument,demonstrated high proliferative activity in HSaVEC,HITAEC,and HMVEC,whilst the in vitro tube formation assay indicated their angiogenic potential. The isolation of HSaVEC,HITAEC,and HMVEC from patients undergoing coronary artery bypass graft surgery is a promising option to investigate endothelial heterogeneity,to interrogate endothelial responses to various stresses,and to pinpoint the optimal approaches for restoring endothelial homeostasis,thereby reproducing them within the bedside-to-bench-to-bedside concept. View Publication

T cell dysfunction is a pivotal driving factor in autoimmune diseases,yet its underlying regulatory mechanisms remain incompletely understood. The role of long non-coding RNAs (lncRNAs) in immune regulation has gradually been recognized,although their functional mechanisms in T cells remain elusive. This study focuses on lncBADR (LncRNA Branched-chain Amino acids Degradation Regulator),elucidating its mechanism by which it regulates branched-chain amino acids (BCAAs) metabolism to influence T cell effector functions. Mice with specific knockout of lncBADR (T celllncBADR−/−) exhibited markedly ameliorated experimental autoimmune encephalomyelitis (EAE) symptoms. Mechanistic investigations revealed that lncBADR inhibits BCAAs degradation by binding to the enzymes Mccc1 and Pcca,leading to the accumulation of BCAAs within T-cells. This,in turn,activates the mTOR-Stat1 signaling pathway,promoting IFN-γ secretion and exacerbating EAE pathology. In contrast,knockout of lncBADR restored BCAAs degradation,significantly reducing IFN-γ secretion in T cells and suppressing their pathogenic functions. Further studies demonstrated that high-BCAAs feeding partially reversed the protective effects of lncBADR knockout,indicating that lncBADR plays a crucial role in autoimmune inflammation by regulating BCAAs metabolism. This study offers new insights into targeting lncBADR or modulating BCAAs metabolism as potential therapeutic strategies for autoimmune diseases. View Publication

Alzheimer’s disease (AD) is a devastating neurodegenerative disorder,with no effective treatment currently available. Recently,non-pharmacological therapy,especially gamma frequency stimulation has shown promising therapeutic effects in Alzheimer’s disease (AD) mouse models. Electric field (EF) is a non-invasive biophysical approach for neuronal protection. However,whether EF is beneficial in AD neuropathology remains unknown. In this study,we exposed the P301S tauopathy mouse model to EF at gamma frequency on the head. We demonstrated that EF treatment significantly improved the cognitive impairments in the P301S mice. This was accompanied by reduced tau pathologies,suppressed microglial activation,neuroinflammation and oxidative stress in the tauopathy mouse brain. Moreover,EF treatment induced cell-specific responses in neural cells,with neurons being more susceptible,followed by microglia and oligodendrocytes. EF also had favorable effects on synaptic protein in neurons,inflammatory response and complement signaling in microglia,and myelination in oligodendrocytes. This study provides strong evidence that EF at gamma frequency may have great potential to be a novel therapeutic intervention for P301S by attenuating neuropathology and offering neuroprotection.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13195-025-01859-8. View Publication

Emerging evidence suggests brain-resident myeloid cells,including perivascular macrophages and microglia,provide a reservoir for HIV infection in the central nervous system (CNS),and their inflammatory activation is a proposed pathogenic mechanism in HIV-associated neurocognitive disorders (HAND). We investigated whether cannabinoid receptor 2 (CB2),an immunomodulatory receptor expressed in myeloid cells,regulates viral replication and inflammation in HIV-infected macrophages and microglia. Using the synthetic CB2-specific agonist JWH-133,we found that CB2 activation reduced HIV replication in primary human monocyte-derived macrophages (MDMs) and human induced pluripotent stem cell-derived microglia (iMg) at differing doses,corresponding to the basal expression of CNR2,which encodes CB2,and related endocannabinoid transcripts in each cell type. JWH-133 broadly reduced release of cytokines from HIV-infected MDMs but not iMg. RNA-seq revealed that CB2 agonism primarily altered interferon and integrated stress response pathways in MDMs while altering homeostatic pathways,including synapse maintenance and phagocytosis,in iMg. Further analyses in iMg revealed that NLRP3 inflammasome activation,but not priming,was reduced by CB2 activation,which did not inhibit HIV-induced nuclear factor kB activation. This study identifies key differences in CB2 response between myeloid lineage cell types and implicates CB2-specific agonists as promising candidates for the regulation of HIV-associated neuroinflammation. View Publication

The generation of the post-cranial embryonic body relies on the coordinated production of spinal cord neurectoderm and presomitic mesoderm cells from neuromesodermal progenitors (NMPs). This process is orchestrated by pro-neural and pro-mesodermal transcription factors that are co-expressed in NMPs together with Hox genes,which are essential for axial allocation of NMP derivatives. NMPs reside in a posterior growth region,which is marked by the expression of Wnt,FGF and Notch signalling components. Although the importance of Wnt and FGF in influencing the induction and differentiation of NMPs is well established,the precise role of Notch remains unclear. Here,we show that the Wnt/FGF-driven induction of NMPs from human embryonic stem cells (hESCs) relies on Notch signalling. Using hESC-derived NMPs and chick embryo grafting,we demonstrate that Notch directs a pro-mesodermal character at the expense of neural fate. We show that Notch also contributes to activation of HOX gene expression in human NMPs,partly in a non-cell-autonomous manner. Finally,we provide evidence that Notch exerts its effects via the establishment of a negative-feedback loop with FGF signalling. View Publication

The transplantation of spinal cord progenitor cells (SCPCs) derived from human-induced pluripotent stem cells (iPSCs) has beneficial effects in treating spinal cord injury (SCI). However,the presence of residual undifferentiated iPSCs among their differentiated progeny poses a high risk as these cells can develop teratomas or other types of tumors post-transplantation. Despite the need to remove these residual undifferentiated iPSCs,no specific surface markers can identify them for subsequent removal. By profiling the size of SCPCs after a 10-day differentiation process,we found that the large-sized group contains significantly more cells expressing pluripotent markers. In this study,we used a sized-based,label-free separation using an inertial microfluidic-based device to remove tumor-risk cells. The device can reduce the number of undifferentiated cells from an SCPC population with high throughput (ie,>3 million cells/minute) without affecting cell viability and functions. The sorted cells were verified with immunofluorescence staining,flow cytometry analysis,and colony culture assay. We demonstrated the capabilities of our technology to reduce the percentage of OCT4-positive cells. Our technology has great potential for the “downstream processing” of cell manufacturing workflow,ensuring better quality and safety of transplanted cells. View Publication

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease which currently lacks effective treatments. Mutations in the RNA-binding protein FUS are a common cause of familial ALS,accounting for around 4% of the cases. Understanding the mechanisms by which mutant FUS becomes toxic to neurons can provide insight into the pathogenesis of both familial and sporadic ALS. We have previously observed that overexpression of wild-type or ALS-mutant FUS in Drosophila motor neurons is toxic,which allowed us to screen for novel genetic modifiers of the disease. Using a genome-wide screening approach,we identified Protein Phosphatase 2A (PP2A) and Glycogen Synthase Kinase 3 (GSK3) as novel modifiers of FUS-ALS. Loss of function or pharmacological inhibition of either protein rescued FUS-associated lethality in Drosophila . Consistent with a conserved role in disease pathogenesis,pharmacological inhibition of both proteins rescued disease-relevant phenotypes,including mitochondrial trafficking defects and neuromuscular junction failure,in patient iPSC-derived spinal motor neurons (iPSC-sMNs). In FUS-ALS flies,mice,and human iPSC-sMNs,we observed reduced GSK3 inhibitory phosphorylation,suggesting that FUS dysfunction results in GSK3 hyperactivity. Furthermore,we found that PP2A acts upstream of GSK3,affecting its inhibitory phosphorylation. GSK3 has previously been linked to kinesin-1 hyperphosphorylation. We observed this in both flies and iPSC-sMNs,and we rescued this hyperphosphorylation by inhibiting GSK3 or PP2A. Moreover,increasing the level of kinesin-1 expression in our Drosophila model strongly rescued toxicity,confirming the relevance of kinesin-1 hyperphosphorylation. Our data provide in vivo evidence that PP2A and GSK3 are disease modifiers,and reveal an unexplored mechanistic link between PP2A,GSK3,and kinesin-1,that may be central to the pathogenesis of FUS-ALS and sporadic forms of the disease. The online version contains supplementary material available at 10.1007/s00401-024-02689-y. View Publication

Ferroptosis is a new form of nonapoptotic and iron-dependent type of cell death. Glutathione peroxidase-4 (GPX4) plays an essential role in anti-ferroptosis by reducing lipid peroxidation. Although acute myeloid leukemia (AML) cells,especially relapsed and refractory (R/R)-AML,present high GPX4 levels and enzyme activities,pharmacological inhibition of GPX4 alone has limited application in AML. Thus,whether inhibition of GPX4 combined with other therapeutic reagents has effective application in AML is largely unknown. Lipid reactive oxygen species (ROS),malondialdehyde (MDA),and glutathione (GSH) assays were used to assess ferroptosis in AML cells treated with the hypomethylating agent (HMA) decitabine (DAC),ferroptosis-inducer (FIN) RAS-selective lethal 3 (RSL3),or their combination. Combination index (CI) analysis was used to assess the synergistic activity of DAC + RSL3 against AML cells. Finally,we evaluated the synergistic activity of DAC + RSL3 in murine AML and a human R/R-AML-xenografted NSG model in vivo. We first assessed GPX4 expression and found that GPX4 levels were higher in AML cells,especially those with MLL rearrangements,than in NCs. Knockdown of GPX4 by shRNA and indirect inhibition of GPX4 enzyme activity by RSL3 robustly induced ferroptosis in AML cells. To reduce the dose of RSL3 and avoid side effects,low doses of DAC (0.5 µM) and RSL3 (0.05 µM) synergistically facilitate ferroptosis by inhibiting the AMP-activated protein kinase (AMPK)-SLC7A11-GPX4 axis. Knockdown of AMPK by shRNA enhanced ferroptosis,and overexpression of SLC7A11 and GPX4 rescued DAC + RSL3-induced anti-leukemogenesis. Mechanistically,DAC increased the expression of MAGEA6 by reducing MAGEA6 promoter hypermethylation. Overexpression of MAGEA6 induced the degradation of AMPK,suggesting that DAC inhibits the AMPK-SLC7A11-GPX4 axis by increasing MAGEA6 expression. In addition,DAC + RSL3 synergistically reduced leukemic burden and extended overall survival compared with either DAC or RSL3 treatment in the MLL-AF9-transformed murine model. Finally,DAC + RSL3 synergistically reduced viability in untreated and R/R-AML cells and extended overall survival in two R/R-AML-xenografted NSG mouse models. Our study first identify vulnerability to ferroptosis by regulating MAGEA6-AMPK-SLC7A11-GPX4 signaling pathway. Combined treatment with HMAs and FINs provides a potential therapeutic choice for AML patients,especially for R/R-AML. The online version contains supplementary material available at 10.1186/s40164-024-00489-4. View Publication

We describe humans with rare biallelic loss-of-function PTCRA variants impairing pre-TCRα expression. Low circulating naïve αβ T cell counts at birth persisted over time,with normal memory αβ and high γδ T cell counts. Their TCRα repertoire was biased,suggesting that noncanonical thymic differentiation pathways can rescue αβ T cell development. Only a minority of these individuals were sick,with infection,lymphoproliferation,and/or autoimmunity. We also report that 1 in 4000 individuals from the Middle East and South Asia are homozygous for a common hypomorphic PTCRA variant. They had normal circulating naïve αβ T cell counts but high γδ T cell counts. Although residual pre-TCRα expression drove the differentiation of more αβ T cells,autoimmune conditions were more frequent in these patients than in the general population. View Publication