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

Cannabinoid receptor 1 (CB1) has been implicated in multiple inflammatory diseases by regulating pro-inflammatory mediators or altering immune cell polarization. However,the expression and direct functional role of CB1 in T cells remain largely unexplored. Here,we demonstrate that primary murine T cells express CB1 and that its novel agonist,BI-5756,directly increases the frequencies of regulatory T cells (Tregs) in primary murine pan T cells after activation. In addition,BI-5756 exhibits an in vivo protective effect against graft-versus-host disease (GvHD),an allogeneic T cell-mediated inflammatory complication after allogeneic hematopoietic cell transplantation (allo-HCT),resulting in an improved overall survival with enhanced platelet recovery and reconstitution of bone marrow-derived B and T cells. BI-5756 also directly suppresses tumor cell growth and upregulates MHC I,MHC II,and CD80 on tumor cells,which may subsequently enhance T cell-mediated anti-tumor responses in mixed lymphocyte reaction with A20 cells. The ability of BI-5756 to increase Tregs was significantly abrogated by rimonabant,a potent and selective CB1 antagonist,suggesting that the immunomodulatory effect of BI-5756 is mediated via CB1. In summary,BI-5756,a potent CB1 agonist,increases Tregs while preserving anti-tumor responses in vitro and effectively reduces GvHD in vivo. View Publication

Transgene silencing provides a significant challenge in animal model production via gene engineering using viral vectors or transposons. Selecting an appropriate strategy,contingent upon the species is crucial to circumvent transgene silencing,necessitating long-term observation of in vivo gene expression. This study employed the PiggyBac transposon to create a GFP rat model to address transgene silencing in rats. Surprisingly,transgene silencing occurred while using the CAG promoter,contrary to conventional understanding,whereas the Ef1α promoter prevented silencing. GFP expression remained stable through over five generations,confirming efficacy of the Ef1α promoter for long-term protein expression in rats. Additionally,GFP expression was consistently maintained at the cellular level in various cellular sources produced from the GFP rats,thereby validating the in vitro GFP expression of GFP rats. Whole-genome sequencing identified a stable integration site in Akap1 between exons 1 and 2,mitigating sequence-independent mechanism-mediated transgene silencing. This study established an efficient method for producing transgenic rat models using PiggyBac transposon. Our GFP rats represent the first model to exhibit prolonged expression of foreign genes over five generations,with implications for future research in gene-engineered rat models. The online version contains supplementary material available at 10.1186/s12917-024-04123-7. View Publication

Acute myeloid leukemia (AML) is a heterogenous disease characterized by the clonal expansion of myeloid progenitor cells. Despite recent advancements in the treatment of AML,relapse still remains a significant challenge,necessitating the development of innovative therapies to eliminate minimal residual disease. One promising approach to address these unmet clinical needs is natural killer (NK) cell immunotherapy. To implement such treatments effectively,it is vital to comprehend how AML cells escape the NK-cell surveillance. Signal transducer and activator of transcription 3 (STAT3),a component of the Janus kinase (JAK)-STAT signaling pathway,is well-known for its role in driving immune evasion in various cancer types. Nevertheless,the specific function of STAT3 in AML cell escape from NK cells has not been deeply investigated. In this study,we unravel a novel role of STAT3 in sensitizing AML cells to NK-cell surveillance. We demonstrate that STAT3-deficient AML cell lines are inefficiently eliminated by NK cells. Mechanistically,AML cells lacking STAT3 fail to form an immune synapse as efficiently as their wild-type counterparts due to significantly reduced surface expression of intercellular adhesion molecule 1 (ICAM-1). The impaired killing of STAT3-deficient cells can be rescued by ICAM-1 overexpression proving its central role in the observed phenotype. Importantly,analysis of our AML patient cohort revealed a positive correlation between ICAM1 and STAT3 expression suggesting a predominant role of STAT3 in ICAM-1 regulation in this disease. In line,high ICAM1 expression correlates with better survival of AML patients underscoring the translational relevance of our findings. Taken together,our data unveil a novel role of STAT3 in preventing AML cells from escaping NK-cell surveillance and highlight the STAT3/ICAM-1 axis as a potential biomarker for NK-cell therapies in AML. View Publication

Streptococcus pneumoniae is a global priority respiratory pathogen that kills over a million people annually. The pore-forming cytotoxin,pneumolysin (PLY) is a major virulence factor. Here,we found that recombinant PLY as well as wild-type pneumococcal strains,but not the isogenic PLY mutant,upregulated the shedding of extracellular vesicles (EVs) harboring membrane-bound toxin from human THP-1 monocytes. PLY-EVs induced cytotoxicity and hemolysis dose-dependently upon internalization by recipient monocyte-derived dendritic cells. Proteomics analysis revealed that PLY-EVs are selectively enriched in key inflammatory host proteins such as IFI16,NLRC4,PTX3,and MMP9. EVs shed from PLY-challenged or infected cells induced dendritic cell maturation and primed them to infection. In vivo,zebrafish administered with PLY-EVs showed pericardial edema and mortality. Adoptive transfer of bronchoalveolar-lavage-derived EVs from infected mice to healthy recipients induced lung damage and inflammation in a PLY-dependent manner. Our findings identify that host EVs released during infection mediate pneumococcal pathogenesis. Subject areas: Microbiology,Bacteriology,Cell biology View Publication

Thyroid hormone receptor alpha (THRα) is a nuclear hormone receptor that binds triiodothyronine (T3) and acts as an important transcription factor in development,metabolism,and reproduction. In mammals,THRα has two major splicing isoforms,THRα1 and THRα2. The better-characterized isoform,THRα1,is a transcriptional stimulator of genes involved in cell metabolism and growth. The less-well-characterized isoform,THRα2,lacks the ligand-binding domain (LBD) and is thought to act as an inhibitor of THRα1 activity. The ratio of THRα1 to THRα2 splicing isoforms is therefore critical for transcriptional regulation in different tissues and during development. However,the expression patterns of both isoforms have not been studied in healthy human tissues or in the developing brain. Given the lack of commercially available isoform-specific antibodies,we addressed this question by analyzing four bulk RNA-sequencing datasets and two scRNA-sequencing datasets to determine the RNA expression levels of human THRA1 and THRA2 transcripts in healthy adult tissues and in the developing brain. We demonstrate how 10X Chromium scRNA-seq datasets can be used to perform splicing-sensitive analyses of isoforms that differ at the 3′-end. In all datasets,we found a strong predominance of THRA2 transcripts at all examined stages of human brain development and in the central nervous system of healthy human adults. View Publication

Isobaric labeling-based mass spectrometry (ILMS) has been widely used to quantify,on a proteome-wide scale,the relative protein abundance in different biological conditions. However,large-scale ILMS data sets typically involve multiple runs of mass spectrometry,bringing great computational difficulty to the integration of ILMS samples. We present zMAP,a toolset that makes ILMS intensities comparable across mass spectrometry runs by modeling the associated mean-variance dependence and accordingly applying a variance stabilizing z-transformation. The practical utility of zMAP is demonstrated in several case studies involving the dynamics of cell differentiation and the heterogeneity across cancer patients. The online version contains supplementary material available at 10.1186/s13059-024-03382-9. View Publication

Autism Spectrum Disorder (ASD) is a developmental disorder characterized by impaired social communication and repetitive behaviors. In recent years,a pharmacological mouse model of ASD involving maternal administration of valproic acid (VPA) has become widely used. Newborn pups in this model show an abnormal balance between excitatory and inhibitory (E/I) signaling in neurons and exhibit ASD-like behavior. However,the molecular basis of this model and its implications for the pathogenesis of ASD in humans remain unknown. Using quantitative secretome analysis,we found that the level of leucine-rich repeat and immunoglobulin domain-containing protein 2 (Lingo2) was upregulated in the conditioned medium of VPA model neurons. This upregulation was associated with excitatory synaptic organizer activity. The secreted form of the extracellular domain of Lingo2 (sLingo2) is produced by the transmembrane metalloprotease ADAM10 through proteolytic processing. sLingo2 was found to induce the formation of excitatory synapses in both mouse and human neurons,and treatment with sLingo2 resulted in an increased frequency of miniature excitatory postsynaptic currents in human neurons. These findings suggest that sLingo2 is an excitatory synapse organizer involved in ASD,and further understanding of the mechanisms by which sLingo2 induces excitatory synaptogenesis is expected to advance our understanding of the pathogenesis of ASD. Subject terms: Autism spectrum disorders,Neuroscience View Publication

Non-Small Cell Lung Cancer (NSCLC) is the leading cause of cancer death worldwide. Although immune checkpoint inhibitors (ICIs) have shown remarkable clinical efficacy,they can also induce a paradoxical cancer acceleration,known as hyperprogressive disease (HPD),whose causative mechanisms are still unclear. This study investigated the mechanisms of ICI resistance in an HPD-NSCLC model. Two primary cell cultures were established from samples of a NSCLC patient,before ICI initiation (“baseline”,NSCLC-B) and during HPD (“hyperprogression”,NSCLC-H). The cell lines were phenotypically and molecularly characterized through immunofluorescence,Western Blotting and RNA-Seq analysis. To assess cell plasticity and aggressiveness,cellular growth patterns were evaluated both in vitro and in vivo through 2D and 3D cell growth assays and patient-derived xenografts establishment. In vitro investigations,including the evaluation of cell sensitivity to interferon-gamma (IFN-γ) and cell response to PD-L1 modulation,were conducted to explore the influence of these factors on cell plasticity regulation. NSCLC-H exhibited increased expression of specific CD44 isoforms and a more aggressive phenotype,including organoid formation ability,compared to NSCLC-B. Plastic changes in NSCLC-H were well described by a deep transcriptome shift,that also affected IFN-γ–related genes,including PD-L1. IFN-γ–mediated cell growth inhibition was compromised in both 2D-cultured NSCLC-B and NSCLC-H cells. Further,the cytokine induced a partial activation of both type I and type II IFN-pathway mediators,together with a striking increase in NSCLC-B growth in 3D cell culture systems. Finally,low IFN-γ doses and PD-L1 modulation both promoted plastic changes in NSCLC-B,increasing CD44 expression and its ability to produce spheres. Our findings identified plasticity as a relevant hallmark of ICI-mediated HPD by demonstrating that ICIs can modulate the IFN-γ and PD-L1 pathways,driving tumor cell plasticity and fueling HPD development. The online version contains supplementary material available at 10.1186/s12967-024-06023-8. View Publication

Chromothripsis,the chaotic shattering and repair of chromosomes,is common in cancer. Whether chromothripsis generates actionable therapeutic targets remains an open question. In a cohort of 64 patients in blast phase of a myeloproliferative neoplasm (BP-MPN),we describe recurrent amplification of a region of chromosome 21q (‘chr. 21amp’) in 25%,driven by chromothripsis in a third of these cases. We report that chr. 21amp BP-MPN has a particularly aggressive and treatment-resistant phenotype. DYRK1A,a serine threonine kinase,is the only gene in the 2.7-megabase minimally amplified region that showed both increased expression and chromatin accessibility compared with non-chr. 21amp BP-MPN controls. DYRK1A is a central node at the nexus of multiple cellular functions critical for BP-MPN development and is essential for BP-MPN cell proliferation in vitro and in vivo,and represents a druggable axis. Collectively,these findings define chr. 21amp as a prognostic biomarker in BP-MPN,and link chromothripsis to a therapeutic target. Subject terms: Leukaemia,DNA sequencing View Publication

JAK (Janus Kinase) inhibitors,such as ruxolitinib,were introduced a decade ago for treatment of myeloproliferative neoplasms (MPN). To evaluate ruxolitinib’s impact on MPN clonal evolution,we interrogate a myelofibrosis patient cohort with longitudinal molecular evaluation and discover that ruxolitinib is associated with clonal outgrowth of RAS pathway mutations. Single-cell DNA sequencing combined with ex vivo treatment of RAS mutated CD34 + primary patient cells,demonstrates that ruxolitinib induces RAS clonal selection both in a JAK/STAT wild-type and hyper-activated context. RAS mutations are associated with decreased transformation-free and overall survival only in patients treated with ruxolitinib. In vitro and in vivo competition assays demonstrate increased cellular fitness of RAS- mutated cells under ruxolitinib or JAK2 knock-down,consistent with an on-target effect. MAPK pathway activation is associated with JAK2 downregulation resulting in enhanced oncogenic potential of RAS mutations. Our results prompt screening for pre-existing RAS mutations in JAK inhibitor treated patients with MPN. Subject terms: Myeloproliferative disease,Cancer therapeutic resistance,Tumour heterogeneity,Cancer genetics View Publication

Metformin rejuvenates adult rat oligodendrocyte progenitor cells (OPCs) allowing more efficient differentiation into oligodendrocytes and improved remyelination,and therefore is of interest as a therapeutic in demyelinating diseases such as multiple sclerosis (MS). Here,we test whether metformin has a similar effect in human stem cell derived-OPCs. We assess how well human monoculture,organoid and chimera model culture systems simulate in vivo adult human oligodendrocytes,finding most close resemblance in the chimera model. Metformin increases myelin proteins and/or sheaths in all models even when human cells remain fetal-like. In the chimera model,metformin leads to increased mitochondrial area both in the human transplanted cells and in the mouse axons with associated increase of mitochondrial function/metabolism transcripts. Human oligodendrocytes from MS brain donors treated pre-mortem with metformin also express similar transcripts. Metformin’s brain effect is thus not cell-specific,alters metabolism in part through mitochondrial changes and leads to more myelin production. This bodes well for clinical trials testing metformin for neuroprotection. Subject terms: Oligodendrocyte,Multiple sclerosis,Multiple sclerosis,Regeneration and repair in the nervous system View Publication

Antibiotic resistance is a threat to human health,yet recent work highlights how loss of resistance may drive pathogenesis in some bacteria. In two recent studies,we found that β-lactam antibiotics and nutrient stresses faced during infection selected for genetic inactivation of the Pseudomonas aeruginosa antibiotic efflux pump mexEFoprN . Unexpectedly,efflux pump mutations increased P. aeruginosa virulence during infection; however,neither the prevalence of mexEFoprN inactivating mutations in real human infections,nor the mechanisms driving increased virulence of efflux pump mutants are known. We hypothesized that human infection would select for virulence enhancing mutations. Using genome sequencing of clinical isolates,we show that mexEFoprN efflux pump inactivating mutations are enriched in P. aeruginosa isolates from cystic fibrosis infections relative to isolates from acute respiratory infections. Combining RNA-seq,metabolomics,genetic approaches,and infection models we show that efflux pump mutants have elevated quorum sensing driven expression of elastase and rhamnolipids which increase P. aeruginosa virulence during acute and chronic infections. Restoration of the efflux pump in a representative respiratory isolate and the notorious cystic fibrosis Liverpool epidemic strain reduced their virulence. These findings suggest that mutations inactivating antibiotic resistance mechanisms could lead to greater patient mortality and morbidity. Subject terms: Antimicrobial resistance,Pathogens,Bacteriology,Molecular evolution View Publication