搜索结果: 'gmp t cell activator'

In Multiple Sclerosis (MS),inflammatory demyelinated lesions in the brain and spinal cord lead to neurodegeneration and progressive disability. Remyelination can restore fast saltatory conduction and neuroprotection but is inefficient in MS especially with increasing age,and is not yet treatable with therapies. Intrinsic and extrinsic inhibition of oligodendrocyte progenitor cell (OPC) function contributes to remyelination failure,and we hypothesised that the transplantation of ‘improved’ OPCs,genetically edited to overcome these obstacles,could improve remyelination. Here,we edit human(h) embryonic stem cell-derived OPCs to be unresponsive to a chemorepellent released from chronic MS lesions,and transplant them into rodent models of chronic lesions. Edited hOPCs display enhanced migration and remyelination compared to controls,regardless of the host age and length of time post-transplant. We show that genetic manipulation and transplantation of hOPCs overcomes the negative environment inhibiting remyelination,with translational implications for therapeutic strategies for people with progressive MS. Subject terms: Multiple sclerosis,Multiple sclerosis,Regeneration View Publication

Venetoclax plus azacitidine treatment is clinically beneficial for elderly and unfit acute myeloid leukemia (AML) patients. However,the treatment is rarely curative,and relapse due to resistant disease eventually emerges. Since no current clinically feasible treatments are known to be effective at the state of acquired venetoclax resistance,this is becoming a major challenge in AML treatment. Studying venetoclax-resistant AML cell lines,we observed that venetoclax induced sublethal apoptotic signaling and DNA damage even though cell survival and growth were unaffected. This effect could be due to venetoclax inducing a sublethal degree of mitochondrial outer membrane permeabilization. Based on these results,we hypothesized that the sublethal apoptotic signaling induced by venetoclax could constitute a vulnerability in venetoclax-resistant AML cells. This was supported by screens with a broad collection of drugs,where we observed a synergistic effect between venetoclax and PARP inhibition in venetoclax-resistant cells. Additionally,the venetoclax-PARP inhibitor combination prevented the acquisition of venetoclax resistance in treatment naïve AML cell lines. Furthermore,the addition of azacitidine to the venetoclax-PARP inhibitor combination enhanced venetoclax induced DNA damage and exhibited exceptional sensitivity and long-term responses in the venetoclax-resistant AML cell lines and samples from AML patients that had clinically relapsed under venetoclax-azacitidine therapy. In conclusion,we mechanistically identify a new vulnerability in acquired venetoclax-resistant AML cells and identify PARP inhibition as a potential therapeutic approach to overcome acquired venetoclax resistance in AML. Subject terms: Acute myeloid leukaemia,Acute myeloid leukaemia View Publication

Our study highlights the role of epigenetic machinery in transformation of normal pluripotent stem cells to variant pluripotent state. We demonstrate the importance of non-histone protein methylation,which underlie the EMT and abnormal differentiation behaviour of variant hESCs. View Publication

PRDX2 is significantly expressed in various cancers and is associated with the proliferation of tumor cells. Nonetheless,the precise mechanism of PRDX2 in tumor immunity remains incompletely understood. This study aims to investigate the impact of PRDX2,which is highly expressed in lung adenocarcinoma,on T cells in the tumor immune microenvironment,and its immune action target to promote the immune escape of lung cancer cells,to provide a theoretical basis for lung adenocarcinoma treatment with PRDX2 as the target. Mouse animal models to verify the effect of Conoidin A treatment on tumor growth and T cell infiltration. Flow cytometry and Western blot verified tumor cell apoptosis in the in vitro co-culture system as well as granzyme B and perforin expression in T cells. RNA-Seq was used to obtain the downstream immune molecule. si-RNA knockdown of Galectin-9 was co-cultured with T cells in vitro. Immunofluorescence and Western blot verified that PRDX2 regulates Galectin-9 expression through HDAC3. PRDX2 expression was negatively correlated with CD8 + T cell expression in LUAD patients. Inhibition of PRDX2 significantly enhanced T-cell killing of LUAD cells and reduced tumor load in both in vitro and in vivo models. Mechanistically,Conoidin A or shRNA_PRDX2 decreased Galectin-9 expression by down-regulating the phosphorylation of HDAC3,consequently enhancing the infiltration and function of CD8 + T cells. This study reveals the role of the PRDX2/HDAC3/Galectin-9 axis in LUAD immune escape and indicates Galectin-9 as a promising target for immunotherapy. The online version contains supplementary material available at 10.1186/s12967-024-05888-z. View Publication

GABA B receptor (GABA B R) activation is known to alleviate pain by reducing neuronal excitability,primarily through inhibition of high voltage‐activated (HVA) calcium (Ca V 2.2) channels and potentiating G protein–coupled inwardly rectifying potassium (GIRK) channels. Although the analgesic properties of small molecules and peptides have been primarily tested on isolated murine dorsal root ganglion (DRG) neurons,emerging strategies to develop,study,and characterise human pluripotent stem cell (hPSC)‐derived sensory neurons present a promising alternative. In this study,hPSCs were efficiently differentiated into peripheral DRG‐induced sensory neurons (iSNs) using a combined chemical and transcription factor‐driven approach via a neural crest cell intermediate. Molecular characterisation and transcriptomic analysis confirmed the expression of key DRG markers such as BRN3A,ISLET1,and PRPH,in addition to GABA B R and ion channels including Ca V 2.2 and GIRK1 in iSNs. Functional characterisation of GABA B R was conducted using whole‐cell patch clamp electrophysiology,assessing neuronal excitability under current‐clamp conditions in the absence and presence of GABA B R agonists baclofen and α‐conotoxin Vc1.1. Both baclofen (100 μM) and Vc1.1 (1 μM) significantly reduced membrane excitability by hyperpolarising the resting membrane potential and increasing the rheobase for action potential firing. In voltage‐clamp mode,baclofen and Vc1.1 inhibited HVA Ca 2+ channel currents,which were attenuated by the selective GABA B R antagonist CGP 55845. However,modulation of GIRK channels by GABA B Rs was not observed in the presence of baclofen or Vc1.1,suggesting that functional GIRK1/2 channels were not coupled to GABA B Rs in hPSC‐derived iSNs. This study is the first to report GABA B R modulation of membrane excitability in iSNs by baclofen and Vc1.1,highlighting their potential as a future model for studying analgesic compounds. View Publication

Hematopoietic stem and progenitor cells (HSPCs) are critical for the treatment of blood diseases in clinic. However,the limited source of HSPCs severely hinders their clinical application. In the embryo,hematopoietic stem cells (HSCs) arise from hemogenic endothelial (HE) cells lining the major arteries in vivo. In this work,by engineering vascular niche endothelial cells (VN-ECs),we generated functional HSPCs in vitro from ECs at various sites,including the aorta-gonad-mesonephros (AGM) region and the placenta. Firstly,we converted mouse embryonic HE cells from the AGM region (aHE) into induced HSPCs (iHSPCs),which have the abilities for multilineage differentiation and self-renewal. Mechanistically,we found that VN-ECs can promote the generation of iHSPCs via secretion of CX3CL1 and IL1A. Next,through VN-EC co-culture,we showed that placental HE (pHE) cells,a type of extra-embryonic HE cells,were successfully converted into iHSPCs (pHE-iHSPCs),which have multilineage differentiation capacity,but exhibit limited self-renewal ability. Furthermore,comparative transcriptome analysis of aHE-iHSPCs and pHE-iHSPCs showed that aHE-iHSPCs highly expressed HSC-specific and self-renewal-related genes. Moreover,experimental validation showed that retinoic acid (RA) treatment promoted the transformation of pHE cells into iHSPCs that have self-renewal ability. Collectively,our results suggested that pHE cells possess the potential to transform into self-renewing iHSPCs through RA treatment,which will facilitate the clinical application of placental endothelial cells in hematopoietic cell generation. Subject terms: Haematopoietic stem cells,Haematopoietic stem cells View Publication

Extracellular vesicles (EVs) derived from human organoids are phospholipid bilayer-bound nanoparticles that carry therapeutic cargo. However,the low yield of EVs remains a critical bottleneck for clinical translation. Vertical-Wheel bioreactors (VWBRs),with unique design features,facilitate the scalable production of EVs secreted by human blood vessel organoids (BVOs) under controlled shear stress,using aggregate- and microcarrier-based culture systems. Human induced pluripotent stem cell-derived BVOs cultured as aggregates or on Synthemax II microcarriers within VWBRs (40 and 80 rpm) were compared to static controls. The organoids were characterized by metabolite profiling,flow cytometry,and gene expression of EV biogenesis markers. EVs were characterized by nanoparticle tracking analysis,electron microscopy,and Western blotting. Lipidomics provided insights into EV lipid composition,while functional assays assessed the impact of EVs in a D-galactose-induced senescence model. VWBR cultures showed more aerobic metabolism and higher expression of EV biogenesis genes compared to the static control. EVs from different conditions were comparable in size,but the yields were significantly higher for microcarrier and dynamic cultures than static aggregates. Lipidomic profiling revealed minimal variation (< 0.36%) in total lipid content; however,distinct differences were identified in lipid chain lengths and saturation levels,affecting key pathways such as sphingolipid and neurotrophin signaling. Human BVO EVs demonstrated the abilities of reducing oxidative stress and increasing cell proliferation in vitro. Human BVOs differentiated in VWBRs (in particular 40 rpm) produce 2–3 fold higher yield of EVs (per mL) than static control. The bio manufactured EVs from VWBRs have exosomal characteristics and therapeutic cargo,showing functional properties in in vitro assays. This innovative approach establishes VWBRs as a scalable platform for producing functional EVs with defined lipid profiles and therapeutic potential,paving the way for future in vivo studies. The online version contains supplementary material available at 10.1186/s13287-025-04317-2. View Publication

Natural killer (NK) cells are exploited in cellular therapies for cancer. While NK cell therapies are efficient against haematological cancers,it has been difficult to target solid tumours due to low tumour infiltration and a hostile tumour microenvironment. NK‐cell derived extracellular vesicles (NK‐EVs) target and kill cancer cells in vitro and represent an alternative treatment strategy for solid tumours. To exploit their potential,it is necessary to standardize NK‐EV production protocols. Here,we have performed a comparative analysis of EVs from the human NK‐92 cell line cultured in five serum‐free commercial media optimized for growth of human NK cells and one serum‐free medium for growth of lymphocytes. The effect of growing the NK‐92 cells in static cell cultures versus shaking flasks was compared. EVs were purified via ultracentrifugation followed by size‐exclusion chromatography. We found that there were no significant differences in EV yield from NK‐92 cells grown under static or dynamic conditions. However,we found clear differences between the different culture media in terms of EV purity as assessed by the enrichment of the CD63 and CD81 markers in the isolates that translated into their capacity to induce apoptosis of the colon cancer cell line HCT 116. These findings will be instructive for the design of future production protocols for therapeutic NK‐cell derived EVs. View Publication

VEXAS syndrome is a clonal hematopoietic disorder characterized by hyperinflammation,bone marrow failure,and high mortality. The molecular hallmark of VEXAS is somatic mutations at methionine 41 (M41) in the E1 ubiquitin enzyme,UBA1. These mutations induce a protein isoform switch,but the mechanisms underlying disease pathogenesis remain unclear. Here,we developed a human cell model of VEXAS syndrome by engineering the male monocytic THP1 cell line to express the common UBA1 M41V mutation. We found that mutant UBA1 M41V cells exhibit aberrant UBA1 isoform expression,increased vacuolization,and upregulation of the unfolded protein response,recapitulating key features of VEXAS. Moreover,proteomic analyses revealed dysregulated ubiquitination and proteotoxic stress in UBA1 M41V cells,with alterations in inflammatory and stress-response pathways. Functional studies demonstrated that UBA1 M41V cells were highly sensitive to genetic or pharmacological inhibition of E1 ubiquitin enzymes. Treatment with the E1 enzyme inhibitor TAK-243 preferentially suppressed colony formation of UBA1 M41V cells as compared to WT cells. Moreover,UBA1 M41V cells exhibited greater sensitivity to TAK-243 in competition assays and showed increased apoptosis. Interestingly,TAK-243 preferentially inhibited UBA6 activity over UBA1,suggesting that UBA6 may compensate for UBA1 dysfunction in UBA1 M41V cells. Targeting UBA6 using shRNA or the UBA6-specific inhibitor phytic acid further revealed an acquired dependency on UBA6 in UBA1 M41V cells. Phytic acid selectively impaired growth and colony formation in UBA1 M41V cells while sparing WT cells,highlighting a potential therapeutic vulnerability. Together,these findings establish a novel human model of VEXAS syndrome,identify key roles for UBA1 and UBA6 in disease pathogenesis,and demonstrate that UBA6 inhibition represents a promising therapeutic strategy for selectively targeting UBA1 mutant clones. Subject terms: Haematological cancer,Cell signalling View Publication

RNA 5-methylcytosine (m 5 C),a prevalent epitranscriptomic modification that critically regulates gene expression and cellular homeostasis. While its roles in solid tumors have been increasingly recognized,the functional landscape of m 5 C in acute myeloid leukemia (AML) remains unexplored. Here,we identified NSUN2,the principal RNA m 5 C methyltransferase,as a key regulator of AML progression. NSUN2 was aberrantly upregulated in AML patient samples and correlated with poor prognosis. Functional studies demonstrated that NSUN2 promoted leukemic cell proliferation,enhanced tumor growth in xenograft models,and conferred resistance to ferroptosis—a regulated cell death process driven by lipid peroxidation. Mechanistically,NSUN2 catalyzed m⁵C deposition on the 3’UTR of FSP1 (ferroptosis suppressor protein 1) mRNA,facilitating its recognition and stabilization by the m 5 C reader protein YBX1. This NSUN2-YBX1-FSP1 axis protected AML cells from ferroptotic stress by suppressing lipid peroxidation and oxidative damage. Depletion of NSUN2 or FSP1 induced mitochondrial remodeling,which primed cells for ferroptosis. Reconstitution of wild-type NSUN2 or FSP1 rescued ferroptosis resistance,whereas catalytically inactive NSUN2 (C271A/C321A) or non-functional FSP1 mutants (G2A/E156A) failed to reverse this phenotype. Pharmacological inhibition of NSUN2 with MY-1B or targeting FSP1 with iFSP1 exhibited potent anti-leukemic effects,synergizing robustly with ferroptosis inducers,standard chemotherapy,and the BCL-2 inhibitor venetoclax. Our study unveils NSUN2 and FSP1 as prognostic biomarkers and therapeutic targets in AML. We highlight a novel epitranscriptomic mechanism linking RNA methylation to ferroptosis evasion,providing a dual-strategy approach to overcome AML treatment resistance. The online version contains supplementary material available at 10.1186/s12943-025-02394-8. View Publication

Due to the complexity of modeling tumor-host interactions within the tumor microenvironment in vitro,we developed a 3D heterotypic cellular breast cancer (BC) model. We generated spheroid models using MCF7,MDA-MB-231,and SK-BR-3 cell lines alongside cancer-associated (BrC4f) and normal (BN120f) fibroblasts in ultra-low attachment plates. Stromal spheroids (3Df) were formed using a liquid overlay technique (graphical abstract). The YT cell line and peripheral blood NK (PB-NK) cells were used as immune components in our 3D model. In this study,we showed that stromal cells promoted tumor cell aggregation into spheroids,regardless of the initial proliferation rates,with NK cells accumulating in fibroblast-rich regions. The presence of CAFs within the model induced alterations in the expression levels of MICA/B and PD-L1 by tumor cells within the 3D-2 model. The feasibility of utilizing a 3D cell BC model in combination with cytokines and PB-NKs was evaluated. We observed that IL-15 and IL-2 enhanced NK cell activity within spheroids,whereas TGFβ had varying effects on proliferation depending on the cell type. Stimulation with IL-2 and IL-15 or TGFβ1 altered PB-NK markers and stimulated their differentiation into ILC1-like cells in 3D models. These findings underscore the regulatory function of CAFs in shaping the response of the tumor microenvironment to immunotherapeutic interventions. View Publication

Despite the success of antiretroviral therapy in suppressing plasma viremia in people living with human immunodeficiency virus type-1 (HIV-1),persistent viral RNA expression in tissue reservoirs is observed and can contribute to HIV-1-induced immunopathology and comorbidities. Infection of long-lived innate immune cells,such as tissue-resident macrophages and microglia may contribute to persistent viral RNA production and chronic inflammation. We recently reported that de novo cytoplasmic expression of HIV-1 intron-containing RNA (icRNA) in macrophages and microglia leads to MDA5 and MAVS-dependent innate immune sensing and induction of type I IFN responses,demonstrating that HIV icRNA is a pathogen-associated molecular pattern (PAMP). In this report,we show that cytoplasmic expression of HIV-1 icRNA also induces NLRP1 inflammasome activation and IL-1β secretion in macrophages and microglia in an RLR- and endosomal TLR-independent manner. Infection of both macrophages and microglia with either replication-competent or single-cycle HIV-1 induced IL-1β secretion,which was attenuated when cytoplasmic expression of viral icRNA was prevented. While IL-1β secretion was blocked by treatment with caspase-1 inhibitors or knockdown of NLRP1 or caspase-1 expression in HIV-infected macrophages,overexpression of NLRP1 significantly enhanced IL-1β secretion in an HIV-icRNA-dependent manner. Immunoprecipitation analysis revealed interaction of HIV-1 icRNA,but not multiply-spliced HIV-1 RNA,with NLRP1,suggesting that HIV-1 icRNA sensing by NLRP1 is sufficient to trigger inflammasome activation. Together,these findings reveal a pathway of NLRP1 inflammasome activation induced by de novo expressed HIV icRNA in HIV-infected myeloid cells. View Publication