搜索结果: 'methocult media formulations for human hematopoietic cells serum containing'

Static gene expression programs have been extensively characterized in stem cells and mature human cells. However,the dynamics of RNA isoform changes upon cell-state-transitions during cell differentiation,the determinants and functional consequences have largely remained unclear. Here,we established an improved model for human neurogenesis in vitro that is amenable for systems-wide analyses of gene expression. Our multi-omics analysis reveals that the pronounced alterations in cell morphology correlate strongly with widespread changes in RNA isoform expression. Our approach identifies thousands of new RNA isoforms that are expressed at distinct differentiation stages. RNA isoforms mainly arise from exon skipping and the alternative usage of transcription start and polyadenylation sites during human neurogenesis. The transcript isoform changes can remodel the identity and functions of protein isoforms. Finally,our study identifies a set of RNA binding proteins as a potential determinant of differentiation stage-specific global isoform changes. This work supports the view of regulated isoform changes that underlie state-transitions during neurogenesis. Synopsis Multi-omics analysis of a newly established human neuronal cell differentiation model reveals widespread dynamic changes in RNA isoform expression,their functional consequences and potential determinants,providing evidence that they underlie cell-state-transitions during neurogenesis. Dynamic changes in RNA and protein levels are strongly correlated during all stages of neuronal differentiation.Nanopore sequencing (ONT-seq) during human neurogenesis reveals 12,019 non-annotated RNA isoforms,a large number of which are differentially expressed during differentiation.70% of new RNA isoforms result from the use of alternative transcription start sites (TSSs) or polyadenylation (pA) sites and exon skipping.RNA isoform changes underlie protein isoform changes during human neurogenesis as revealed by integrating ONT-seq,RNA-seq and proteomics time course data.RNA motif enrichment,RNA-seq and available CLIP-seq data uncover a set of RNA binding proteins (RBPs) as potential determinants of differentiation stage-specific global isoform changes. Multi-omics analysis of a newly established human neuronal cell differentiation model reveals widespread dynamic changes in RNA isoform expression,their functional consequences and potential determinants,providing evidence that they underlie cell-state-transitions during neurogenesis. View Publication

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiac disorder characterized by sodium channel dysfunction. However,the clinical management of ARVC remains challenging. Identifying novel compounds for the treatment of ARVC is crucial for advancing drug development.PurposeIn this study,we aim to identify novel compounds for treating ARVC.MethodsMachine learning (ML) models were constructed using proteins analyzed from the scRNA-seq data of ARVC rats and their corresponding protein-protein interaction (PPI) network to predict binding affinity (BA). To validate these predictions,a series of experiments in cardiac organoids were conducted,including Western blotting,ELISA,MEA,and Masson staining to assess the effects of these compounds.ResultsWe first discovered and identified SCN5A as the most significantly affected sodium channel protein in ARVC. ML models predicted that Kaempferol binds to SCN5A with high affinity. In vitro experiments further confirmed that Kaempferol exerted therapeutic effects in ARVC.ConclusionThis study presents a novel approach for identifying potential compounds to treat ARVC. By integrating ML modeling with organoid validation,our platform provides valuable support in addressing the public health challenges posed by ARVC,with broad application prospects. Kaempferol shows promise as a lead compound for ARVC treatment. View Publication

Energetic stress compels cells to evolve adaptive mechanisms to adjust their metabolism. Inhibition of mTOR kinase complex 1 (mTORC1) is essential for cell survival during glucose starvation. How mTORC1 controls cell viability during glucose starvation is not well understood. Here we show that the mTORC1 effectors eukaryotic initiation factor 4E binding proteins 1/2 (4EBP1/2) confer protection to mammalian cells and budding yeast under glucose starvation. Mechanistically,4EBP1/2 promote NADPH homeostasis by preventing NADPH-consuming fatty acid synthesis via translational repression of Acetyl-CoA Carboxylase 1 (ACC1),thereby mitigating oxidative stress. This has important relevance for cancer,as oncogene-transformed cells and glioma cells exploit the 4EBP1/2 regulation of ACC1 expression and redox balance to combat energetic stress,thereby supporting transformation and tumorigenicity in vitro and in vivo. Clinically,high EIF4EBP1 expression is associated with poor outcomes in several cancer types. Our data reveal that the mTORC1-4EBP1/2 axis provokes a metabolic switch essential for survival during glucose starvation which is exploited by transformed and tumor cells. How cells adapt to glucose starvation is still elusive. Here,Levy et al. show that the mTOR substrate 4EBP1 protects human,mouse,and yeast cells from glucose starvation and is exploited by cancer cells to promote tumorigenesis. View Publication

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

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

BackgroundAt present,hepatic ischemia-reperfusion injury (IRI) is an important complication of partial hepatectomy and liver transplantation,and it is an important cause of poor prognosis. Spleen tyrosine kinase(SYK) plays an important role in a variety of signaling pathways in the liver,but its role in hepatic IRI is still unclear. This study aims to investigate the role and mechanism of SYK in hepatic IRI and tumor recurrence.MethodsWe first observed the activation of SYK in the liver of mice in response to hepatic IRI. Subsequently,Pharmacological inhibitions of SYK were used to evaluated the effect of SYK on neutrophil recruitment and NETosis,and further explored the effect of SYK on IRI and tumor recurrence.ResultsOur study shows that SYK is activated in response to hepatic IRI and aggravates liver injury. On the one hand,neutrophils SYK during the early stage of liver reperfusion increases neutrophil extracellular traps (NETs) production by promoting Pyruvate kinase M2(PKM2) nuclear translocation leading to upregulation of phosphorylated STAT3,thereby exacerbating liver inflammation and tumor recurrence. On the other hand,macrophages SYK can promote the recruitment of neutrophils and increase the activation of NLRP3 inflammasome and IL1β,which further promotes the formation of NETs.ConclusionsOur study demonstrates that neutrophil and macrophage SYK synergistically promote hepatic IRI and tumor recurrence,and SYK may be a potential target to improve postoperative hepatic IRI and tumor recurrence.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10020-024-00907-7. View Publication

AbstractBackgroundAcute graft‐versus‐host disease (aGVHD) arises from the imbalance of host T cells. Galectin‐9 negatively regulates CD4 effector T cell (Th1 and Th17) function by binding to Tim‐3. However,the relationship between Galectin‐9/Tim‐3 and CD4+ T subsets in patients with aGVHD after Haplo‐HSCT (haploidentical peripheral blood hematopoietic stem cell transplantation) has not been fully elucidated. Here,we investigated the role of Galectin‐9 and CD4+T subsets in aGVHD after haplo‐HSCT.MethodsForty‐two patients underwent Haplo‐HSCT (26 without aGVHD and 16 with aGVHD),and 20 healthy controls were included. The concentrations of Galectin‐9,interferon‐gamma (IFN‐γ),interleukin (IL)‐4,transforming growth factor (TGF)‐β,and IL‐17 in the serum and culture supernatant were measured using enzyme‐linked immunosorbent assay or cytometric bead array. The expression levels of Galectin‐9,PI3K,p‐PI3K,and p‐mTOR protein were detected by western blot analysis. Flow cytometry was used to analyze the proportions of CD4+ T cell subsets. Bioinformatics analysis was performed.ResultsIn patients with aGVHD,regulatory T (Treg) cells and Galectin‐9 decreased,and the Th1,Th17,and Treg cells were significantly imbalanced. Moreover,Treg and Galectin‐9 were rapidly reconstituted in the early stage of patients without aGVHD after Haplo‐HSCT,but Th17 cells were reconstituted slowly. Furthermore,Tim‐3 upregulation on Th17 and Th1 cells was associated with excessive activation of the PI3K/AKT pathway in patients with aGVHD. Specifically,in vitro treatment with Galectin‐9 reduced IFN‐γ and IL‐17 production while augmenting TGF‐β secretion. Bioinformatics analysis suggested the potential involvement of the PI3K/AKT/mTOR pathway in aGVHD. Mechanistically,exogenous Galectin‐9 was found to mitigate aGVHD by restoring the Treg/Teffs (effector T cells) balance and suppressing PI3K.ConclusionGalectin‐9 may ameliorate aGVHD after haplo‐HSCT by modulating Treg/Teffs balance and regulating the PI3K/AKT/mTOR pathway. Targeting Galectin‐9 may hold potential value for the treatment of aGVHD. In patients with acute graft‐versus‐host disease (aGVHD),the expression of Tim‐3 is significantly increased. Galectin‐9 binding to Tim‐3 may inhibit the activation of the PI3K/AKT pathway and enhance the function of Treg cells. On the other hand,transforming growth factor (TGF)‐β promotes the differentiation of Treg cells through autocrine secretion,while TGF‐β induces the expression of Galectin‐9 in a paracrine manner. The increased Treg cells can inhibit the activation of Th1 and Th17 cells by secreting TGF‐β,thus alleviating aGVHD and inducing immune tolerance View Publication

IntroductionHumanization is typically adopted to reduce the immunogenicity of murine antibodies generated by hybridoma technology when used in humans.MethodsTwo different strategies of antibody humanization are popularly employed,including “complementarity determining region (CDR) grafting” and “framework (FR) shuffling” to humanize a murine antibody against human programmed death-1 (PD-1),XM PD1. In CDR-grafting humanization,the CDRs of XM PD-1,were grafted into the human FR regions with high homology to the murine FR counterparts,and back mutations of key residues were performed to retain the antigen-binding affinities. While in FR-shuffling humanization,a combinatorial library of the six murine CDRs in-frame of XM PD-1 was constructed to a pool of human germline FRs for high-throughput screening for the most favorable variants. We evaluated many aspects which were important during antibody development of the molecules obtained by the two methods,including antibody purity,thermal stability,binding efficacy,predicted humanness,and immunogenicity,along with T cell epitope prediction for the humanized antibodies.ResultsWhile the ideal molecule was not achieved through CDR grafting in this particular instance,FR-shuffling proved successful in identifying a suitable candidate. The study highlights FR-shuffling as an effective complementary approach that potentially increases the success rate of antibody humanization. It is particularly noted for its accessibility to those with a biological rather than a computational background. DiscussionThe insights from this comparison are intended to assist other researchers in selecting appropriate humanization strategies for drug development,contributing to broader application and understanding in the field. View Publication

Simple SummaryAcute myeloid leukemia (AML) is a challenging blood cancer to treat,with only about 24% of patients surviving for 5 years after diagnosis. A key challenge is that AML cells stick to normal cells in the bone marrow (BM),and these BM cells protect them from chemotherapy. The aim of this project is to find drugs that disrupt AML cell adherence to BM cells and release them into the blood,where chemotherapy will be more effective. To achieve this,we have created a model of adhesive BM and shown that it mimics the drug resistance seen clinically. We have used the model as a testing platform for drugs that disrupt AML cell adhesion. We have shown that the combined targeting of CD44 and FAK,using anti-CD44 and the clinical-grade FAK inhibitor defactinib,inhibits the adhesion of the most primitive AML cells that are associated with drug resistance and disease relapse. AbstractBackground/Objectives: Acute myeloid leukemia (AML) is an aggressive neoplasm. Although most patients respond to induction therapy,they commonly relapse due to recurrent disease in the bone marrow microenvironment (BMME). So,the disruption of the BMME,releasing tumor cells into the peripheral circulation,has therapeutic potential. Methods: Using both primary donor AML cells and cell lines,we developed an in vitro co-culture model of the AML BMME. We used this model to identify the most effective agent(s) to block AML cell adherence and reverse adhesion-mediated treatment resistance. Results: We identified that anti-CD44 treatment significantly increased the efficacy of cytarabine. However,some AML cells remained adhered,and transcriptional analysis identified focal adhesion kinase (FAK) signaling as a contributing factor; the adhered cells showed elevated FAK phosphorylation that was reduced by the FAK inhibitor,defactinib. Importantly,we demonstrated that anti-CD44 and defactinib were highly synergistic at diminishing the adhesion of the most primitive CD34high AML cells in primary autologous co-cultures. Conclusions: Taken together,we identified anti-CD44 and defactinib as a promising therapeutic combination to release AML cells from the chemoprotective AML BMME. As anti-CD44 is already available as a recombinant humanized monoclonal antibody,the combination of this agent with defactinib could be rapidly tested in AML clinical trials. View Publication

Co-stimulatory molecules are imperative for CD8+ T cells to eliminate target cell and maintain sustained cytotoxicity. Despite an advanced understanding of the co-stimulatory molecules deficiency that results in tumor escape,the tumor cell-intrinsic mechanisms that regulate co-stimulatory molecules remain enigmatic,and an in-depth dissection could facilitate the improvement of treatment options. To this end,in this study,we report that the deficiency of the critical costimulatory molecule CD58,mediated by the expression of ATF4 in tumor cells,impairs the formation of immunological synapses (IS) and leads to the deterioration of antitumor immune function of CD8+ T cells. Mechanistically,ATF4 transcriptionally upregulated dynamin 1 (DNM1) expression leading to DNM1-dependent endocytosis (DDE)-mediated degradation of CD58. Furthermore,administration of DDE inhibitor prochlorperazine or ATF4 knockdown effectively restored CD58 expression,boosting CD8+ T cell cytotoxicity and immunotherapy efficiency. Thus,our study reveals that ATF4 in tumor cells weakens CD58 expression to interfere with complete IS formation,and indicates potential approaches to improve the cytolytic function of CD8+ T cell in tumor immunotherapy.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12967-025-06245-4. 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