Bhushal S et al. ( 2017)
Frontiers in immunology 8 JUN 671
Cell Polarization and Epigenetic Status Shape the Heterogeneous Response to Type III Interferons in Intestinal Epithelial Cells.
Type I and type III interferons (IFNs) are crucial components of the first-line antiviral host response. While specific receptors for both IFN types exist,intracellular signaling shares the same Jak-STAT pathway. Due to its receptor expression,IFN-λ responsiveness is restricted mainly to epithelial cells. Here,we display IFN-stimulated gene induction at the single cell level to comparatively analyze the activities of both IFN types in intestinal epithelial cells and mini-gut organoids. Initially,we noticed that the response to both types of IFNs at low concentrations is based on a single cell decision-making determining the total cell intrinsic antiviral activity. We identified histone deacetylase (HDAC) activity as a crucial restriction factor controlling the cell frequency of IFN-stimulated gene (ISG) induction upon IFN-λ but not IFN-β stimulation. Consistently,HDAC blockade confers antiviral activity to an elsewise non-responding subpopulation. Second,in contrast to the type I IFN system,polarization of intestinal epithelial cells strongly enhances their ability to respond to IFN-λ signaling and raises the kinetics of gene induction. Finally,we show that ISG induction in mini-gut organoids by low amounts of IFN is characterized by a scattered heterogeneous responsiveness of the epithelial cells and HDAC activity fine-tunes exclusively IFN-λ activity. This study provides a comprehensive description of the differential response to type I and type III IFNs and demonstrates that cell polarization in gut epithelial cells specifically increases IFN-λ activity.
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(Apr 2025)
Biotechnology Journal 20 4
Cell Seeding Strategy Influences Metabolism and Differentiation Potency of Human Induced Pluripotent Stem Cells Into Pancreatic Progenitors
ABSTRACTHuman induced pluripotent stem cells (iPSCs) are an invaluable endless cell source for generating various therapeutic cells and tissues. However,their differentiation into specific cell lineages,such as definitive endoderm (DE) and pancreatic progenitor (PP),often suffers from poor reproducibility,due partially to their pluripotency. In this work,we investigated the impact of iPSC confluency during cell self?renewal and seeding density on cell metabolic activity,glycolysis to oxidative phosphorylation shift,and differentiation potential toward DE and PP lineages. Our findings demonstrated that cell seeding strategy influences cellular metabolic activity and the robustness of iPSC differentiation. iPSCs maintained at higher seeding density exhibited lower initial oxygen consumption rate (OCR) and metabolic activity. There is an optimal seeding density to ensure sufficient oxygen consumption during differentiation and to yield high expression of SOX17 in the DE lineage and high PDX1/NKX6.1 dual?positive cells in PPs. Interestingly,we found that cell confluency at the time of harvest has less impact on the efficacy of pancreatic lineage formation or metabolic activity. This study sheds light on the interplay between metabolic activity and iPSC lineage specification,offering new insights into the robustness of iPSC self?renewal and differentiation for creating human tissues. Graphical Abstract and Lay SummaryHuman induced pluripotent stem cell (iPSC) differentiation into specific cell lineages often shows poor reproducibility due to cell pluripotency. This study demonstrated impact of iPSC seeding strategy on metabolic activity and differentiation potential,offering new insights into the robustness of iPSC self?renewal and differentiation for creating human tissues.
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Young ARJ et al. ( 2013)
965 1 1--13
Cell senescence as both a dynamic and a static phenotype
It has been 50 years since cellular senescence was first described in human diploid fibroblasts (HDFs),yet its mechanism as well as its physiological and clinical implications are still not fully appreciated. Recent progress suggests that cellular senescence is a collective phenotype,composed of complex networks of effector programs. The balance and quality within the effector network varies depending on the cell type,the nature of the stress as well as the context. Therefore,understanding each of these effectors in the context of the whole network will be necessary in order to fully understand senescence as a whole. Furthermore,searching for new effector programs of senescence will help to define this heterogeneous and complex phenotype according to cellular contexts.
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McBeath R et al. (APR 2004)
Developmental cell 6 4 483--95
Commitment of stem cells to different lineages is regulated by many cues in the local tissue microenvironment. Here we demonstrate that cell shape regulates commitment of human mesenchymal stem cells (hMSCs) to adipocyte or osteoblast fate. hMSCs allowed to adhere,flatten,and spread underwent osteogenesis,while unspread,round cells became adipocytes. Cell shape regulated the switch in lineage commitment by modulating endogenous RhoA activity. Expressing dominant-negative RhoA committed hMSCs to become adipocytes,while constitutively active RhoA caused osteogenesis. However,the RhoA-mediated adipogenesis or osteogenesis was conditional on a round or spread shape,respectively,while constitutive activation of the RhoA effector,ROCK,induced osteogenesis independent of cell shape. This RhoA-ROCK commitment signal required actin-myosin-generated tension. These studies demonstrate that mechanical cues experienced in developmental and adult contexts,embodied by cell shape,cytoskeletal tension,and RhoA signaling,are integral to the commitment of stem cell fate.
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(Aug 2024)
Stem Cell Reports 19 8
Cell size regulates human endoderm specification through actomyosin-dependent AMOT-YAP signaling
SummaryCell size is a crucial physical property that significantly impacts cellular physiology and function. However,the influence of cell size on stem cell specification remains largely unknown. Here,we investigated the dynamic changes in cell size during the differentiation of human pluripotent stem cells into definitive endoderm (DE). Interestingly,cell size exhibited a gradual decrease as DE differentiation progressed with higher stiffness. Furthermore,the application of hypertonic pressure or chemical to accelerate the reduction in cell size significantly and specifically enhanced DE differentiation. By functionally intervening in mechanosensitive elements,we have identified actomyosin activity as a crucial mediator of both DE differentiation and cell size reduction. Mechanistically,the reduction in cell size induces actomyosin-dependent angiomotin (AMOT) nuclear translocation,which suppresses Yes-associated protein (YAP) activity and thus facilitates DE differentiation. Together,our study has established a novel connection between cell size diminution and DE differentiation,which is mediated by AMOT nuclear translocation. Additionally,our findings suggest that the application of osmotic pressure can effectively promote human endodermal lineage differentiation. Graphical abstract Highlights•Cell size decreases during the differentiation of human pluripotent stem cells into endoderm•Hypertonic pressure is conducive to the differentiation of human definitive endoderm•Actomyosin contributes to both size diminution and endoderm promotion under hypertonic pressure•Cell size diminution represses YAP activity via promoting AMOT nuclear translocation Jiang and colleagues show that cell size exhibits a gradual decrease during human endoderm differentiation. The application of hypertonic pressure or chemical to accelerate the reduction in cell size significantly and specifically enhanced endoderm differentiation. This enhancement is reliant on actomyosin activity and achieved by promoting the nuclear translocation of AMOT,thereby repressing YAP activity.
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Sallan SE et al. (MAR 1980)
Blood 55 3 395--402
Cell surface antigens: prognostic implications in childhood acute lymphoblastic leukemia.
Lymphoblasts from 93 children with acute lymphoblastic leukemia (ALL) were characterized by immunologic cell surface markers. These patients were treated on a single protocol,featuring adriamycin therapy during remission,and have been followed from 2 to 6.5 yr (median 4 yr). Three classes of patients were defined serologically: HTA+ Ia- CALLA-,Ia+ CALLA+ HTA-,and Ia+ CALLA- HTA-. Disease-free survival and sites of relapse were assessed within immunologic subsets. Similar to the findings of others,T-cell (HTA+ Ia-) patients fared poorly as compared to non-T-cell (Ia+ HTA-) patients (median disease-free survival was 12 and 47 mo. respectively; p = 0.0004). The majority of relapses in the HTA+ patients occurred at extramedullary sites. Late testicular relapse was rare among Ia+ patients. In addition,the common ALL antigen" (CALLA) may identify a relatively favorable subset within the Ia+ population. The prognostic value of the immunologic markers was compared with traditional clinical factors. There was much overlap between HTA+�
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Cretenet G et al. (APR 2016)
Scientific Reports 6 24129
Cell surface Glut1 levels distinguish human CD4 and CD8 T lymphocyte subsets with distinct effector functions.
CD4 and CD8 T lymphocyte activation requires the generation of sufficient energy to support new biosynthetic demands. Following T cell receptor (TCR) engagement,these requirements are met by an increased glycolysis,due,at least in part,to induction of the Glut1 glucose transporter. As Glut1 is upregulated on tumor cells in response to hypoxia,we assessed whether surface Glut1 levels regulate the antigen responsiveness of human T lymphocytes in both hypoxic and atmospheric oxygen conditions. Notably,Glut1 upregulation in response to TCR stimulation was significantly higher in T lymphocytes activated under hypoxic as compared to atmospheric oxygen conditions. Furthermore,TCR-stimulated human T lymphocytes sorted on the basis of Glut1-Lo and Glut1-Hi profiles maintained distinct characteristics,irrespective of the oxygen tension. While T cells activated in hypoxia divided less than those activated in atmospheric oxygen,Glut1-Hi lymphocytes exhibited increased effector phenotype acquisition,augmented proliferation,and an inverted CD4/CD8 ratio in both oxygen conditions. Moreover,Glut1-Hi T lymphocytes exhibited a significantly enhanced ability to produce IFN-γ and this secretion potential was completely dependent on continued glycolysis. Thus,Glut1 surface levels identify human T lymphocytes with distinct effector functions in both hypoxic and atmospheric oxygen tensions.
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(Sep 2024)
Journal of Experimental & Clinical Cancer Research : CR 43
Cell therapy using ex vivo reprogrammed macrophages enhances antitumor immune responses in melanoma
BackgroundMacrophage-based cell therapies have shown modest success in clinical trials,which can be attributed to their phenotypic plasticity,where transplanted macrophages get reprogrammed towards a pro-tumor phenotype. In most tumor types,including melanoma,the balance between antitumor M1-like and tumor-promoting M2-like macrophages is critical in defining the local immune response with a higher M1/M2 ratio favoring antitumor immunity. Therefore,designing novel strategies to increase the M1/M2 ratio in the TME has high clinical significance and benefits macrophage-based cell therapies.MethodsIn this study,we reprogrammed antitumor and proinflammatory macrophages ex-vivo with HDAC6 inhibitors (HDAC6i). We administered the reprogrammed macrophages intratumorally as an adoptive cell therapy (ACT) in the syngeneic SM1 murine melanoma model and patient-derived xenograft bearing NSG-SGM3 humanized mouse models. We phenotyped the tumor-infiltrated immune cells by flow cytometry and histological analysis of tumor sections for macrophage markers. We performed bulk RNA-seq profiling of murine bone marrow-derived macrophages treated with vehicle or HDAC6i and single-cell RNA-seq profiling of SM1 tumor-infiltrated immune cells to determine the effect of intratumor macrophage ACT on the tumor microenvironment (TME). We further analyzed the single-cell data to identify key cell-cell interactions and trajectory analysis to determine the fate of tumor-associated macrophages post-ACT.ResultsMacrophage ACT resulted in diminished tumor growth in both mouse models. We also demonstrated that HDAC6 inhibition in macrophages suppressed the polarization toward tumor-promoting phenotype by attenuating STAT3-mediated M2 reprogramming. Two weeks post-transplantation,ACT macrophages were viable,and inhibition of HDAC6 rendered intratumor transplanted M1 macrophages resistant to repolarization towards protumor M2 phenotype in-vivo. Further characterization of tumors by flow cytometry,single-cell transcriptomics,and single-cell secretome analyses revealed a significant enrichment of antitumor M1-like macrophages,resulting in increased M1/M2 ratio and infiltration of CD8 effector T-cells. Computational analysis of single-cell RNA-seq data for cell-cell interactions and trajectory analyses indicated activation of monocytes and T-cells in the TME.ConclusionsIn summary,for the first time,we demonstrated the potential of reprogramming macrophages ex-vivo with HDAC6 inhibitors as a viable macrophage cell therapy to treat solid tumors.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13046-024-03182-w.
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(May 2025)
Nature Communications 16
Cell trajectory modulation: rapid microfluidic biophysical profiling of CAR T cell functional phenotypes
Chimeric Antigen Receptor (CAR) T cell therapy is a pivotal treatment for hematological malignancies. However,CAR T cell products exhibit batch-to-batch variability in cell number,quality,and in vivo efficacy due to donor-to-donor heterogeneity,and pre/post-manufacturing processes,and the manufacturing of such products necessitates careful testing,both post-manufacturing and pre-infusion. Here,we introduce the Cell Trajectory Modulation (CTM) assay,a microfluidic,label-free approach for the rapid evaluation of the functional attributes of CAR T cells based on biophysical features (i.e.,size,deformability). CTM assay correlates with phenotypic metrics,including CD4:CD8 ratio,memory subtypes,and cytotoxic activity. Validated across multiple donors and culture platforms,the CTM assay requires fewer than 10,000 cells and delivers results within 10 minutes. Compared to labeled flow cytometry processing,the CTM assay offers real-time data to guide adaptive manufacturing workflows. Thus,the CTM assay offers an improvement over existing phenotypic assessments,marking a step forward in advancing CAR T cell therapy manufacturing. CAR T cell manufacturing faces significant challenges that impact cell quality and in vivo efficacy. This necessitates reliable cellular characterization methods. Here the authors present a real-time,label-free,microfluidic method that profiles cellular biophysical properties and correlates them to activation state and CAR T potency,facilitating the rapid phenotypic cell assessment during production.
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Phetfong J et al. (JUL 2016)
Cell and Tissue Research 365 1 101--112
Cell type of origin influences iPSC generation and differentiation to cells of the hematoendothelial lineage
The use of induced pluripotent stem cells (iPSCs) as a source of cells for cell-based therapy in regenerative medicine is hampered by the limited efficiency and safety of the reprogramming procedure and the low efficiency of iPSC differentiation to specialized cell types. Evidence suggests that iPSCs retain an epigenetic memory of their parental cells with a possible influence on their differentiation capacity in vitro. We reprogramme three cell types,namely human umbilical cord vein endothelial cells (HUVECs),endothelial progenitor cells (EPCs) and human dermal fibroblasts (HDFs),to iPSCs and compare their hematoendothelial differentiation capacity. HUVECs and EPCs were at least two-fold more efficient in iPSC reprogramming than HDFs. Both HUVEC- and EPC-derived iPSCs exhibited high potentiality toward endothelial cell differentiation compared with HDF-derived iPSCs. However,only HUVEC-derived iPSCs showed efficient differentiation to hematopoietic stem/progenitor cells. Examination of DNA methylation at promoters of hematopoietic and endothelial genes revealed evidence for the existence of epigenetic memory at the endothelial genes but not the hematopoietic genes in iPSCs derived from HUVECs and EPCs indicating that epigenetic memory involves an endothelial differentiation bias. Our findings suggest that endothelial cells and EPCs are better sources for iPSC derivation regarding their reprogramming efficiency and that the somatic cell type used for iPSC generation toward specific cell lineage differentiation is of importance.
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K. Tan et al. (May 2025)
Nucleic Acids Research 53 9
Cell type- and factor-specific nonsense-mediated RNA decay
Nonsense-mediated RNA decay (NMD) is a highly conserved RNA turnover pathway that influences several biological processes. Specific features in messenger RNAs (mRNAs) have been found to trigger decay by NMD,leading to the assumption that NMD sensitivity is an intrinsic quality of a given transcript. Here,we provide evidence that,instead,an overriding factor dictating NMD sensitivity is the cell environment. Using several genome-wide techniques to detect NMD-target mRNAs,we find that hundreds of mRNAs are sensitized to NMD as human embryonic stem cells progress to form neural progenitor cells. Another class of mRNAs escape from NMD during this developmental progression. We show that the differential sensitivity to NMD extends to in vivo scenarios,and that the RNA-binding protein,HNRNPL,has a role in cell type-specific NMD. We also addressed another issue in the field—whether NMD factors are core or branch-specific in their action. Surprisingly,we found that UPF3B,an NMD factor critical for the nervous system,shares only 30% of NMD-target transcripts with the core NMD factor UPF2. Together,our findings have implications for how NMD is defined and measured,how NMD acts in different biological contexts,and how different NMD branches influence human diseases.
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Bershteyn M et al. (MAR 2014)
Nature 507 7490 99--103
Cell-autonomous correction of ring chromosomes in human induced pluripotent stem cells.
Ring chromosomes are structural aberrations commonly associated with birth defects,mental disabilities and growth retardation. Rings form after fusion of the long and short arms of a chromosome,and are sometimes associated with large terminal deletions. Owing to the severity of these large aberrations that can affect multiple contiguous genes,no possible therapeutic strategies for ring chromosome disorders have been proposed. During cell division,ring chromosomes can exhibit unstable behaviour leading to continuous production of aneuploid progeny with low viability and high cellular death rate. The overall consequences of this chromosomal instability have been largely unexplored in experimental model systems. Here we generated human induced pluripotent stem cells (iPSCs) from patient fibroblasts containing ring chromosomes with large deletions and found that reprogrammed cells lost the abnormal chromosome and duplicated the wild-type homologue through the compensatory uniparental disomy (UPD) mechanism. The karyotypically normal iPSCs with isodisomy for the corrected chromosome outgrew co-existing aneuploid populations,enabling rapid and efficient isolation of patient-derived iPSCs devoid of the original chromosomal aberration. Our results suggest a fundamentally different function for cellular reprogramming as a means of /`chromosome therapy/' to reverse combined loss-of-function across many genes in cells with large-scale aberrations involving ring structures. In addition,our work provides an experimentally tractable human cellular system for studying mechanisms of chromosomal number control,which is of critical relevance to human development and disease.
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