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1.
Cell ; 187(13): 3409-3426.e24, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38744281

ABSTRACT

Alterations in extracellular matrix (ECM) architecture and stiffness represent hallmarks of cancer. Whether the biomechanical property of ECM impacts the functionality of tumor-reactive CD8+ T cells remains largely unknown. Here, we reveal that the transcription factor (TF) Osr2 integrates biomechanical signaling and facilitates the terminal exhaustion of tumor-reactive CD8+ T cells. Osr2 expression is selectively induced in the terminally exhausted tumor-specific CD8+ T cell subset by coupled T cell receptor (TCR) signaling and biomechanical stress mediated by the Piezo1/calcium/CREB axis. Consistently, depletion of Osr2 alleviates the exhaustion of tumor-specific CD8+ T cells or CAR-T cells, whereas forced Osr2 expression aggravates their exhaustion in solid tumor models. Mechanistically, Osr2 recruits HDAC3 to rewire the epigenetic program for suppressing cytotoxic gene expression and promoting CD8+ T cell exhaustion. Thus, our results unravel Osr2 functions as a biomechanical checkpoint to exacerbate CD8+ T cell exhaustion and could be targeted to potentiate cancer immunotherapy.


Subject(s)
CD8-Positive T-Lymphocytes , Transcription Factors , Animals , Female , Humans , Mice , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Line, Tumor , Cyclic AMP Response Element-Binding Protein/metabolism , Extracellular Matrix/metabolism , Histone Deacetylases/metabolism , Mice, Inbred C57BL , Neoplasms/immunology , Neoplasms/metabolism , Receptors, Antigen, T-Cell/metabolism , Signal Transduction , T-Cell Exhaustion , Transcription Factors/metabolism , Tumor Microenvironment , Stress, Mechanical
2.
Cell ; 184(5): 1245-1261.e21, 2021 03 04.
Article in English | MEDLINE | ID: mdl-33636132

ABSTRACT

How early events in effector T cell (TEFF) subsets tune memory T cell (TMEM) responses remains incompletely understood. Here, we systematically investigated metabolic factors in fate determination of TEFF and TMEM cells using in vivo pooled CRISPR screening, focusing on negative regulators of TMEM responses. We found that amino acid transporters Slc7a1 and Slc38a2 dampened the magnitude of TMEM differentiation, in part through modulating mTORC1 signaling. By integrating genetic and systems approaches, we identified cellular and metabolic heterogeneity among TEFF cells, with terminal effector differentiation associated with establishment of metabolic quiescence and exit from the cell cycle. Importantly, Pofut1 (protein-O-fucosyltransferase-1) linked GDP-fucose availability to downstream Notch-Rbpj signaling, and perturbation of this nutrient signaling axis blocked terminal effector differentiation but drove context-dependent TEFF proliferation and TMEM development. Our study establishes that nutrient uptake and signaling are key determinants of T cell fate and shape the quantity and quality of TMEM responses.


Subject(s)
Amino Acids/metabolism , CD8-Positive T-Lymphocytes/cytology , Immunologic Memory , Signal Transduction , Amino Acid Transport Systems/metabolism , Animals , CD8-Positive T-Lymphocytes/immunology , CRISPR-Cas Systems , Cell Cycle , Cell Differentiation , Disease Models, Animal , Female , Gene Knock-In Techniques , Lymphocytic Choriomeningitis/immunology , Male , Mice , Mice, Transgenic , Precursor Cells, T-Lymphoid/cytology
3.
Nat Immunol ; 24(10): 1735-1747, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37679549

ABSTRACT

Neurodegenerative diseases, including Alzheimer's disease (AD), are characterized by innate immune-mediated inflammation, but functional and mechanistic effects of the adaptive immune system remain unclear. Here we identify brain-resident CD8+ T cells that coexpress CXCR6 and PD-1 and are in proximity to plaque-associated microglia in human and mouse AD brains. We also establish that CD8+ T cells restrict AD pathologies, including ß-amyloid deposition and cognitive decline. Ligand-receptor interaction analysis identifies CXCL16-CXCR6 intercellular communication between microglia and CD8+ T cells. Further, Cxcr6 deficiency impairs accumulation, tissue residency programming and clonal expansion of brain PD-1+CD8+ T cells. Ablation of Cxcr6 or CD8+ T cells ultimately increases proinflammatory cytokine production from microglia, with CXCR6 orchestrating brain CD8+ T cell-microglia colocalization. Collectively, our study reveals protective roles for brain CD8+ T cells and CXCR6 in mouse AD pathogenesis and highlights that microenvironment-specific, intercellular communication orchestrates tissue homeostasis and protection from neuroinflammation.

4.
Nature ; 624(7990): 154-163, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37968405

ABSTRACT

CD8+ cytotoxic T cells (CTLs) orchestrate antitumour immunity and exhibit inherent heterogeneity1,2, with precursor exhausted T (Tpex) cells but not terminally exhausted T (Tex) cells capable of responding to existing immunotherapies3-7. The gene regulatory network that underlies CTL differentiation and whether Tex cell responses can be functionally reinvigorated are incompletely understood. Here we systematically mapped causal gene regulatory networks using single-cell CRISPR screens in vivo and discovered checkpoints for CTL differentiation. First, the exit from quiescence of Tpex cells initiated successive differentiation into intermediate Tex cells. This process is differentially regulated by IKAROS and ETS1, the deficiencies of which dampened and increased mTORC1-associated metabolic activities, respectively. IKAROS-deficient cells accumulated as a metabolically quiescent Tpex cell population with limited differentiation potential following immune checkpoint blockade (ICB). Conversely, targeting ETS1 improved antitumour immunity and ICB efficacy by boosting differentiation of Tpex to intermediate Tex cells and metabolic rewiring. Mechanistically, TCF-1 and BATF are the targets for IKAROS and ETS1, respectively. Second, the RBPJ-IRF1 axis promoted differentiation of intermediate Tex to terminal Tex cells. Accordingly, targeting RBPJ enhanced functional and epigenetic reprogramming of Tex cells towards the proliferative state and improved therapeutic effects and ICB efficacy. Collectively, our study reveals that promoting the exit from quiescence of Tpex cells and enriching the proliferative Tex cell state act as key modalities for antitumour effects and provides a systemic framework to integrate cell fate regulomes and reprogrammable functional determinants for cancer immunity.


Subject(s)
Cell Differentiation , Clustered Regularly Interspaced Short Palindromic Repeats , Gene Editing , Mutagenesis , Neoplasms , Single-Cell Analysis , T-Lymphocytes, Cytotoxic , Humans , Cell Differentiation/drug effects , Cell Differentiation/genetics , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Immune Checkpoint Inhibitors/immunology , Immune Checkpoint Inhibitors/pharmacology , Neoplasms/genetics , Neoplasms/immunology , Single-Cell Analysis/methods , T-Lymphocytes, Cytotoxic/cytology , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism
5.
Nature ; 621(7977): 179-187, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37648857

ABSTRACT

Tissue resident memory CD8+ T (TRM) cells offer rapid and long-term protection at sites of reinfection1. Tumour-infiltrating lymphocytes with characteristics of TRM cells maintain enhanced effector functions, predict responses to immunotherapy and accompany better prognoses2,3. Thus, an improved understanding of the metabolic strategies that enable tissue residency by T cells could inform new approaches to empower immune responses in tissues and solid tumours. Here, to systematically define the basis for the metabolic reprogramming supporting TRM cell differentiation, survival and function, we leveraged in vivo functional genomics, untargeted metabolomics and transcriptomics of virus-specific memory CD8+ T cell populations. We found that memory CD8+ T cells deployed a range of adaptations to tissue residency, including reliance on non-steroidal products of the mevalonate-cholesterol pathway, such as coenzyme Q, driven by increased activity of the transcription factor SREBP2. This metabolic adaptation was most pronounced in the small intestine, where TRM cells interface with dietary cholesterol and maintain a heightened state of activation4, and was shared by functional tumour-infiltrating lymphocytes in diverse tumour types in mice and humans. Enforcing synthesis of coenzyme Q through deletion of Fdft1 or overexpression of PDSS2 promoted mitochondrial respiration, memory T cell formation following viral infection and enhanced antitumour immunity. In sum, through a systematic exploration of TRM cell metabolism, we reveal how these programs can be leveraged to fuel memory CD8+ T cell formation in the context of acute infections and enhance antitumour immunity.


Subject(s)
CD8-Positive T-Lymphocytes , Lymphocytes, Tumor-Infiltrating , Neoplasms , Animals , Humans , Mice , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Cell Respiration , Cholesterol/metabolism , Cholesterol/pharmacology , Immunologic Memory , Intestine, Small/drug effects , Intestine, Small/metabolism , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Metabolomics , Mevalonic Acid/metabolism , Neoplasms/immunology , Ubiquinone/metabolism , Virus Diseases/immunology , Viruses/immunology , Mitochondria/metabolism
6.
Nature ; 607(7917): 135-141, 2022 07.
Article in English | MEDLINE | ID: mdl-35732731

ABSTRACT

The identification of mechanisms to promote memory T (Tmem) cells has important implications for vaccination and anti-cancer immunotherapy1-4. Using a CRISPR-based screen for negative regulators of Tmem cell generation in vivo5, here we identify multiple components of the mammalian canonical BRG1/BRM-associated factor (cBAF)6,7. Several components of the cBAF complex are essential for the differentiation of activated CD8+ T cells into T effector (Teff) cells, and their loss promotes Tmem cell formation in vivo. During the first division of activated CD8+ T cells, cBAF and MYC8 frequently co-assort asymmetrically to the two daughter cells. Daughter cells with high MYC and high cBAF display a cell fate trajectory towards Teff cells, whereas those with low MYC and low cBAF preferentially differentiate towards Tmem cells. The cBAF complex and MYC physically interact to establish the chromatin landscape in activated CD8+ T cells. Treatment of naive CD8+ T cells with a putative cBAF inhibitor during the first 48 h of activation, before the generation of chimeric antigen receptor T (CAR-T) cells, markedly improves efficacy in a mouse solid tumour model. Our results establish cBAF as a negative determinant of Tmem cell fate and suggest that manipulation of cBAF early in T cell differentiation can improve cancer immunotherapy.


Subject(s)
CD8-Positive T-Lymphocytes , Cell Differentiation , DNA Helicases , Multiprotein Complexes , Nuclear Proteins , Proto-Oncogene Proteins c-myc , Transcription Factors , Animals , CD8-Positive T-Lymphocytes/cytology , DNA Helicases/metabolism , Disease Models, Animal , Immunologic Memory , Immunotherapy , Memory T Cells/cytology , Mice , Multiprotein Complexes/chemistry , Multiprotein Complexes/metabolism , Neoplasms , Nuclear Proteins/metabolism , Proto-Oncogene Proteins c-myc/metabolism , Receptors, Chimeric Antigen , Transcription Factors/metabolism
7.
Nature ; 595(7869): 724-729, 2021 07.
Article in English | MEDLINE | ID: mdl-34234346

ABSTRACT

T follicular helper (TFH) cells are crucial for B cell-mediated humoral immunity1. Although transcription factors such as BCL6 drive the differentiation of TFH cells2,3, it is unclear whether and how post-transcriptional and metabolic programs enforce TFH cell programming. Here we show that the cytidine diphosphate (CDP)-ethanolamine pathway co-ordinates the expression and localization of CXCR5 with the responses of TFH cells and humoral immunity. Using in vivo CRISPR-Cas9 screening and functional validation in mice, we identify ETNK1, PCYT2, and SELENOI-enzymes in the CDP-ethanolamine pathway for de novo synthesis of phosphatidylethanolamine (PE)-as selective post-transcriptional regulators of TFH cell differentiation that act by promoting the surface expression and functional effects of CXCR5. TFH cells exhibit unique lipid metabolic programs and PE is distributed to the outer layer of the plasma membrane, where it colocalizes with CXCR5. De novo synthesis of PE through the CDP-ethanolamine pathway co-ordinates these events to prevent the internalization and degradation of CXCR5. Genetic deletion of Pcyt2, but not of Pcyt1a (which mediates the CDP-choline pathway), in activated T cells impairs the differentiation of TFH cells, and this is associated with reduced humoral immune responses. Surface levels of PE and CXCR5 expression on B cells also depend on Pcyt2. Our results reveal that phospholipid metabolism orchestrates post-transcriptional mechanisms for TFH cell differentiation and humoral immunity, highlighting the metabolic control of context-dependent immune signalling and effector programs.


Subject(s)
Immunity, Humoral , Phosphatidylethanolamines/metabolism , Receptors, CXCR5/immunology , T-Lymphocytes, Helper-Inducer/immunology , Animals , B-Lymphocytes/immunology , CRISPR-Cas Systems , Cell Differentiation , Cytidine Diphosphate , Female , Gene Expression Regulation , Humans , Leukocytes, Mononuclear/immunology , Lymphocyte Activation , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Phosphotransferases (Alcohol Group Acceptor) , RNA Nucleotidyltransferases , Signal Transduction
8.
Nature ; 600(7888): 308-313, 2021 12.
Article in English | MEDLINE | ID: mdl-34795452

ABSTRACT

Nutrients are emerging regulators of adaptive immunity1. Selective nutrients interplay with immunological signals to activate mechanistic target of rapamycin complex 1 (mTORC1), a key driver of cell metabolism2-4, but how these environmental signals are integrated for immune regulation remains unclear. Here we use genome-wide CRISPR screening combined with protein-protein interaction networks to identify regulatory modules that mediate immune receptor- and nutrient-dependent signalling to mTORC1 in mouse regulatory T (Treg) cells. SEC31A is identified to promote mTORC1 activation by interacting with the GATOR2 component SEC13 to protect it from SKP1-dependent proteasomal degradation. Accordingly, loss of SEC31A impairs T cell priming and Treg suppressive function in mice. In addition, the SWI/SNF complex restricts expression of the amino acid sensor CASTOR1, thereby enhancing mTORC1 activation. Moreover, we reveal that the CCDC101-associated SAGA complex is a potent inhibitor of mTORC1, which limits the expression of glucose and amino acid transporters and maintains T cell quiescence in vivo. Specific deletion of Ccdc101 in mouse Treg cells results in uncontrolled inflammation but improved antitumour immunity. Collectively, our results establish epigenetic and post-translational mechanisms that underpin how nutrient transporters, sensors and transducers interplay with immune signals for three-tiered regulation of mTORC1 activity and identify their pivotal roles in licensing T cell immunity and immune tolerance.


Subject(s)
CRISPR-Cas Systems , Gene Editing , Nutrients , Protein Interaction Maps , T-Lymphocytes, Regulatory , Animals , Female , Male , Mice , Carrier Proteins/metabolism , CRISPR-Cas Systems/genetics , Forkhead Transcription Factors/metabolism , Genome/genetics , Homeostasis , Immune Tolerance , Inflammation/pathology , Mechanistic Target of Rapamycin Complex 1/metabolism , Neoplasms/immunology , Nuclear Proteins/metabolism , Nutrients/metabolism , Proteasome Endopeptidase Complex/metabolism , Proteolysis , S-Phase Kinase-Associated Proteins/metabolism , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Trans-Activators/metabolism
9.
Nature ; 576(7787): 471-476, 2019 12.
Article in English | MEDLINE | ID: mdl-31827283

ABSTRACT

Adoptive cell therapy represents a new paradigm in cancer immunotherapy, but it can be limited by the poor persistence and function of transferred T cells1. Here we use an in vivo pooled CRISPR-Cas9 mutagenesis screening approach to demonstrate that, by targeting REGNASE-1, CD8+ T cells are reprogrammed to long-lived effector cells with extensive accumulation, better persistence and robust effector function in tumours. REGNASE-1-deficient CD8+ T cells show markedly improved therapeutic efficacy against mouse models of melanoma and leukaemia. By using a secondary genome-scale CRISPR-Cas9 screening, we identify BATF as the key target of REGNASE-1 and as a rheostat that shapes antitumour responses. Loss of BATF suppresses the increased accumulation and mitochondrial fitness of REGNASE-1-deficient CD8+ T cells. By contrast, the targeting of additional signalling factors-including PTPN2 and SOCS1-improves the therapeutic efficacy of REGNASE-1-deficient CD8+ T cells. Our findings suggest that T cell persistence and effector function can be coordinated in tumour immunity and point to avenues for improving the efficacy of adoptive cell therapy for cancer.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Immunotherapy, Adoptive/methods , Leukemia/immunology , Leukemia/therapy , Melanoma/immunology , Melanoma/therapy , Molecular Targeted Therapy , Ribonucleases/metabolism , Animals , Basic-Leucine Zipper Transcription Factors/deficiency , Basic-Leucine Zipper Transcription Factors/metabolism , CD8-Positive T-Lymphocytes/cytology , CRISPR-Cas Systems/genetics , Disease Models, Animal , Female , Gene Deletion , Humans , Leukemia/genetics , Leukemia/metabolism , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Melanoma/genetics , Melanoma/metabolism , Mice , Mitochondria/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 2/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 2/metabolism , Reproducibility of Results , Ribonucleases/deficiency , Ribonucleases/genetics , Ribonucleases/immunology , Suppressor of Cytokine Signaling 1 Protein/genetics , Suppressor of Cytokine Signaling 1 Protein/metabolism , Tumor Microenvironment/immunology
10.
Chem Soc Rev ; 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38855878

ABSTRACT

Seawater electrolysis for the production of fuels and chemicals involved in onshore and offshore plants powered by renewable energies offers a promising avenue and unique advantages for energy and environmental sustainability. Nevertheless, seawater electrolysis presents long-term challenges and issues, such as complex composition, potential side reactions, deposition of and poisoning by microorganisms and metal ions, as well as corrosion, thus hindering the rapid development of seawater electrolysis technology. This review focuses on the production of value-added fuels (hydrogen and beyond) and fine chemicals through seawater electrolysis, as a promising step towards sustainable energy development and carbon neutrality. The principle of seawater electrolysis and related challenges are first introduced, and the redox reaction mechanisms of fuels and chemicals are summarized. Strategies for operating anodes and cathodes including the development and application of chloride- and impurity-resistant electrocatalysts/membranes are reviewed. We comprehensively summarize the production of fuels and chemicals (hydrogen, carbon monoxide, sulfur, ammonia, etc.) at the cathode and anode via seawater electrolysis, and propose other potential strategies for co-producing fine chemicals, even sophisticated and electronic chemicals. Seawater electrolysis can drive the oxidation and upgrading of industrial pollutants or natural organics into value-added chemicals or degrade them into harmless substances, which would be meaningful for environmental protection. Finally, the perspective and prospects are outlined to address the challenges and expand the application of seawater electrolysis.

11.
Small ; : e2306410, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38456764

ABSTRACT

Electrooxidation of biomass into fine chemicals coupled with energy-saving hydrogen production for a zero-carbon economy holds great promise. Advanced anode catalysts determine the cell voltage and electrocatalytic efficiency greatly, further the rational design and optimization of their active site coordination remains a challenge. Herein, a phosphorus-oxygen terminals-rich species (Ni2 P-O-300) via an anion-assisted pyrolysis strategy is reported to induce strong electronic coupling and high valence state of active nickel sites over nickel phosphide. This ultimately facilitates the rapid yet in-situ formation of high-valence nickel with a high reaction activity under electrochemical conditions, and exhibits a low potential of 1.33 V vs. RHE at 10 mA cm-2 , exceeding most of reported transition metal-based catalysts. Advanced spectroscopy, theoretical calculations, and experiments reveal that the functional P-O species can induce the favorable local bonding configurations for electronic coupling, promoting the electron transfer from Ni to P and the adsorption of benzyl alcohol (BA). Finally, the hydrogen production efficiency and kinetic constant of BA electrooxidation by Ni2 P-O-300 are increased by 9- and 2.8- fold compared with the phosphorus-oxygen terminals-deficient catalysts (Ni2 P-O-500). This provides an anion-assisted pyrolysis strategy to modulate the electronic environment of the Ni site, enabling a guideline for Ni-based energy/catalysis systems.

12.
Nature ; 561(7721): 63-69, 2018 09.
Article in English | MEDLINE | ID: mdl-30158707

ABSTRACT

Glutamine synthetase, encoded by the gene GLUL, is an enzyme that converts glutamate and ammonia to glutamine. It is expressed by endothelial cells, but surprisingly shows negligible glutamine-synthesizing activity in these cells at physiological glutamine levels. Here we show in mice that genetic deletion of Glul in endothelial cells impairs vessel sprouting during vascular development, whereas pharmacological blockade of glutamine synthetase suppresses angiogenesis in ocular and inflammatory skin disease while only minimally affecting healthy adult quiescent endothelial cells. This relies on the inhibition of endothelial cell migration but not proliferation. Mechanistically we show that in human umbilical vein endothelial cells GLUL knockdown reduces membrane localization and activation of the GTPase RHOJ while activating other Rho GTPases and Rho kinase, thereby inducing actin stress fibres and impeding endothelial cell motility. Inhibition of Rho kinase rescues the defect in endothelial cell migration that is induced by GLUL knockdown. Notably, glutamine synthetase palmitoylates itself and interacts with RHOJ to sustain RHOJ palmitoylation, membrane localization and activation. These findings reveal that, in addition to the known formation of glutamine, the enzyme glutamine synthetase shows unknown activity in endothelial cell migration during pathological angiogenesis through RHOJ palmitoylation.


Subject(s)
Endothelial Cells/enzymology , Endothelial Cells/pathology , Glutamate-Ammonia Ligase/metabolism , Glutamine/biosynthesis , Neovascularization, Pathologic , Actins/metabolism , Animals , Cell Movement , Endothelial Cells/metabolism , Female , Glutamate-Ammonia Ligase/deficiency , Glutamate-Ammonia Ligase/genetics , Glutamate-Ammonia Ligase/physiology , HEK293 Cells , Human Umbilical Vein Endothelial Cells/cytology , Human Umbilical Vein Endothelial Cells/enzymology , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Lipoylation , Mice , Palmitic Acid/metabolism , Protein Processing, Post-Translational , Stress Fibers/metabolism , rho GTP-Binding Proteins/chemistry , rho GTP-Binding Proteins/metabolism , rho-Associated Kinases/metabolism
13.
Immunol Rev ; 295(1): 15-38, 2020 05.
Article in English | MEDLINE | ID: mdl-32212344

ABSTRACT

The evolutionarily conserved serine/threonine kinase mTOR (mechanistic target of rapamycin) forms the distinct protein complexes mTORC1 and mTORC2 and integrates signals from the environment to coordinate downstream signaling events and various cellular processes. T cells rely on mTOR activity for their development and to establish their homeostasis and functional fitness. Here, we review recent progress in our understanding of the upstream signaling and downstream targets of mTOR. We also provide an updated overview of the roles of mTOR in T-cell development, homeostasis, activation, and effector-cell fate decisions, as well as its important impacts on the suppressive activity of regulatory T cells. Moreover, we summarize the emerging roles of mTOR in T-cell exhaustion and transdifferentiation. A better understanding of the contribution of mTOR to T-cell fate decisions will ultimately aid in the therapeutic targeting of mTOR in human disease.


Subject(s)
Signal Transduction , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , TOR Serine-Threonine Kinases/metabolism , Animals , Cell Differentiation/genetics , Cell Differentiation/immunology , Cell Transdifferentiation/immunology , Cytokines/metabolism , Cytoskeleton/metabolism , Energy Metabolism , Humans , Immunologic Memory , Lymphocyte Activation/immunology , Mechanistic Target of Rapamycin Complex 1/metabolism , Mechanistic Target of Rapamycin Complex 2/metabolism , Receptors, Antigen, T-Cell/metabolism
14.
Nature ; 542(7639): 49-54, 2017 02 02.
Article in English | MEDLINE | ID: mdl-28024299

ABSTRACT

Lymphatic vessels are lined by lymphatic endothelial cells (LECs), and are critical for health. However, the role of metabolism in lymphatic development has not yet been elucidated. Here we report that in transgenic mouse models, LEC-specific loss of CPT1A, a rate-controlling enzyme in fatty acid ß-oxidation, impairs lymphatic development. LECs use fatty acid ß-oxidation to proliferate and for epigenetic regulation of lymphatic marker expression during LEC differentiation. Mechanistically, the transcription factor PROX1 upregulates CPT1A expression, which increases acetyl coenzyme A production dependent on fatty acid ß-oxidation. Acetyl coenzyme A is used by the histone acetyltransferase p300 to acetylate histones at lymphangiogenic genes. PROX1-p300 interaction facilitates preferential histone acetylation at PROX1-target genes. Through this metabolism-dependent mechanism, PROX1 mediates epigenetic changes that promote lymphangiogenesis. Notably, blockade of CPT1 enzymes inhibits injury-induced lymphangiogenesis, and replenishing acetyl coenzyme A by supplementing acetate rescues this process in vivo.


Subject(s)
Fatty Acids/chemistry , Fatty Acids/metabolism , Lymphangiogenesis , Lymphatic Vessels/cytology , Lymphatic Vessels/metabolism , Acetates/pharmacology , Acetyl Coenzyme A/metabolism , Acetylation/drug effects , Animals , Carnitine O-Palmitoyltransferase/antagonists & inhibitors , Carnitine O-Palmitoyltransferase/genetics , Carnitine O-Palmitoyltransferase/metabolism , Cell Differentiation/drug effects , Cell Differentiation/genetics , Endothelial Cells/cytology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Epigenesis, Genetic , Female , Histones/metabolism , Homeodomain Proteins/metabolism , Human Umbilical Vein Endothelial Cells , Humans , Lymphangiogenesis/drug effects , Lymphangiogenesis/genetics , Lymphatic Vessels/drug effects , Mice , Mice, Inbred C57BL , Oxidation-Reduction/drug effects , Protein Biosynthesis , Transcription, Genetic , Tumor Suppressor Proteins/metabolism , Umbilical Arteries/cytology , Up-Regulation
15.
Angew Chem Int Ed Engl ; 62(4): e202216321, 2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36414544

ABSTRACT

Electrocatalytic synthesis of aldehydes from alcohols exhibits unique superiorities as a promising technology, in which cascade reactions are involved. However, the cascade reactions are severely limited by the low selectivity resulting from the peroxidation of aldehydes in a traditional liquid-solid system. Herein, we report a novel liquid-liquid-solid system to regulate the selectivity of benzyl alcohol electrooxidation. The selectivity of benzaldehyde increases 200-fold from 0.4 % to 80.4 % compared with the liquid-solid system at a high current density of 136 mA cm-2 , which is the highest one up to date. In the tri-phase system, the benzaldehyde peroxidation is suppressed efficiently, with the conversion of benzaldehyde being decreased from 87.6 % to 3.8 %. The as-produced benzaldehyde can be in situ extracted to toluene phase and separated from the electrolyte to get purified benzaldehyde. This strategy provides an efficient way to efficiently enhance the selectivity of electrocatalytic cascade reactions.

16.
EMBO J ; 36(16): 2334-2352, 2017 08 15.
Article in English | MEDLINE | ID: mdl-28659375

ABSTRACT

Endothelial cell (EC) metabolism is emerging as a regulator of angiogenesis, but the precise role of glutamine metabolism in ECs is unknown. Here, we show that depriving ECs of glutamine or inhibiting glutaminase 1 (GLS1) caused vessel sprouting defects due to impaired proliferation and migration, and reduced pathological ocular angiogenesis. Inhibition of glutamine metabolism in ECs did not cause energy distress, but impaired tricarboxylic acid (TCA) cycle anaplerosis, macromolecule production, and redox homeostasis. Only the combination of TCA cycle replenishment plus asparagine supplementation restored the metabolic aberrations and proliferation defect caused by glutamine deprivation. Mechanistically, glutamine provided nitrogen for asparagine synthesis to sustain cellular homeostasis. While ECs can take up asparagine, silencing asparagine synthetase (ASNS, which converts glutamine-derived nitrogen and aspartate to asparagine) impaired EC sprouting even in the presence of glutamine and asparagine. Asparagine further proved crucial in glutamine-deprived ECs to restore protein synthesis, suppress ER stress, and reactivate mTOR signaling. These findings reveal a novel link between endothelial glutamine and asparagine metabolism in vessel sprouting.


Subject(s)
Asparagine/metabolism , Cell Movement/drug effects , Cell Proliferation/drug effects , Endothelial Cells/drug effects , Endothelial Cells/physiology , Glutamine/metabolism , Neovascularization, Physiologic/drug effects , Culture Media/chemistry , Endothelial Cells/metabolism , Glutaminase/metabolism , Human Umbilical Vein Endothelial Cells , Humans , Metabolic Networks and Pathways , Neovascularization, Pathologic
17.
Analyst ; 146(15): 4934-4944, 2021 Jul 26.
Article in English | MEDLINE | ID: mdl-34254080

ABSTRACT

It is urgent to obtain targeted drugs that selectively bind to pathological targets rather than physiological targets in the early stage of drug screening. G-Quadruplex has become one of the important targets in the development of anti-tumor drugs. However, drugs that target quadruplexes may also bind to dsDNA, which may lead to adverse reactions. In this study, a new three-phase laminar flow chip was constructed to enable the multi-components of a traditional Chinese medicine extract to dynamically and competitively bind with G-quadruplex DNA (on target) and double-stranded DNA (off target), so as to select high-efficiency and low-toxicity anti-tumor drugs. The results showed that there were five compounds in the extracts of Macleaya cordata seeds that exhibited obvious differences in binding to the two targets. Furthermore, the binding constants and modes of four identified alkaloids as they bound to two DNA targets were verified by fluorescence spectra and molecular docking methods. The toxicity to HepG2 and LO2 cells from the four alkaloids was also compared. The results showed that sanguinarine and chelerythrine could be used as candidate drugs with stronger binding to HT24 than DNA26. The chip can also be used for other types of double-target screening of other traditional Chinese medicine extracts or compound libraries.


Subject(s)
Alkaloids , Papaveraceae , Alkaloids/toxicity , Molecular Docking Simulation , Plant Extracts/toxicity , Seeds
18.
J Cell Biochem ; 120(2): 1869-1877, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30216517

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the effect of FTY720, an agonist of the sphingosine 1-phosphate (S1P) receptor, on the embryo loss rate in mice of spontaneous abortion model and the underlying mechanism. METHODS: The effect of intraperitoneal injection of FTY720 on the embryo loss rate in mice of spontaneous abortion model was observed. The expression of S1PR on the dendritic cell (DC) surface was detected by reverse transcription polymerase chain reaction. The quantity and maturation of DCs in peripheral blood and local tissues of pregnant mice, and the expression of CCL19 as well as its receptor C-C chemokine receptor 7 (CCR7) were detected by flow cytometry and immunohistochemistry. Chemotaxis assay was performed to verify the effect of FTY720 on the chemotaxis of DCs. RESULTS: (1) FTY720 had no significant effect on the embryo loss rate in normal pregnant rats. In contrast, adoptive transferring of FTY720 significantly reduced the embryo loss rate of the spontaneous abortion mouse model (P < 0.05). (2) S1PR was extensively expressed on DC surface. The S1P receptor agonist FTY720 reduced the expressions of DC surface chemokines and its receptor (P < 0.05), resulting in a significant reduction in the number of DCs that were chemoattracted to maternal-fetal interface flow cytometry (P < 0.05). (3) FTY720 had no significant effect on the differentiation and apoptosis rate of DCs (P > 0.05). CONCLUSION: We hypothesized that FTY720 may reduce the number of DCs that were chemoattracted to the maternal-fetal interface by downregulating the expression of CCR7, which ultimately induces maternal-fetal immune tolerance.

19.
Small ; 15(18): e1901015, 2019 May.
Article in English | MEDLINE | ID: mdl-30957431

ABSTRACT

Coordination tuning of catalysts is a highly effective strategy for activating and improving the intrinsic activity. Herein, a Co-engineered FeOOH catalyst integrated on carbon fiber paper (Co-FeOOH/CFP) is reported, which realized a great improvement of the oxygen evolution activity by tuning the coordination geometry of the Fe species with an electrochemically driven method. Experiments and theoretical calculation demonstrate that the FeO bonds of FeOOH are partially broken, which is rooted in the Co incorporation, thus resulting in unsaturated FeO6 ligand structures and a relatively narrow bandgap. Consequently, the reorganized Fe sites on the surface show an enhanced capability for adsorbing OH- species and the Co-FeOOH exhibits an improved conductivity. As expected, the Co-FeOOH/CFP hybrids exhibit an extremely low overpotential of ≈250 mV at 10 mA cm-2 and a small Tafel slope, which far outperforms that of electrochemically sluggish FeOOH. The present work emphasizes the importance of local Fe coordination in catalysis and provides an in-depth insight into the mechanism of the enhanced catalytic activity.

20.
Chemistry ; 25(60): 13683-13687, 2019 Oct 28.
Article in English | MEDLINE | ID: mdl-31402521

ABSTRACT

The Pd/C catalysts are widely used in synthesis of fine chemicals in industry, but their production suffers from a complicated two-step process involving impregnation and reduction, and requires large amounts of solvents and reductant, which would lead to a series of issues such as time consumption, resource waste and environmental pollution. Herein, ultra-small Pd nanoparticles uniformly anchored on carbon nanotubes (Pd/CNTs) were synthesized by using a one-pot and low-temperature reduction strategy. The present process/technology is very sensitive to and controlled by the supports and solvents, and the carbon support and acetic acid synergistically play crucial and decisive roles in the fast production of Pd/C catalysts. Also, the used solvents can be recycled and reutilized, which meets the requirements of sustainable chemistry and green economy. When the as-obtained Pd/CNTs catalyst was used to catalyze the oxidation of benzyl alcohol to benzaldehyde, it achieved a conversion efficiency as high as 99.3 % and a high selectivity up to >99.9 %. The simple, scalable and environmentally friendly strategy can be extended to anchor Pd nanoparticles on various carbon substrates, which sheds a new light on the synthesis of Pd/C catalysts.

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