ABSTRACT
Multiple sclerosis (MS) is a T cell-mediated autoimmune disease of the central nervous system (CNS). Bone marrow hematopoietic stem and progenitor cells (HSPCs) rapidly sense immune activation, yet their potential interplay with autoreactive T cells in MS is unknown. Here, we report that bone marrow HSPCs are skewed toward myeloid lineage concomitant with the clonal expansion of T cells in MS patients. Lineage tracing in experimental autoimmune encephalomyelitis, a mouse model of MS, reveals remarkable bone marrow myelopoiesis with an augmented output of neutrophils and Ly6Chigh monocytes that invade the CNS. We found that myelin-reactive T cells preferentially migrate into the bone marrow compartment in a CXCR4-dependent manner. This aberrant bone marrow myelopoiesis involves the CCL5-CCR5 axis and augments CNS inflammation and demyelination. Our study suggests that targeting the bone marrow niche presents an avenue to treat MS and other autoimmune disorders.
Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Multiple Sclerosis , Animals , Bone Marrow , Hematopoiesis , Humans , Mice , Mice, Inbred C57BLABSTRACT
Reduced infiltration of anti-tumor lymphocytes remains a major cause of tumor immune evasion and is correlated with poor cancer survival. Here, we found that upregulation of regulator of G protein signaling (RGS)1 in helper TH1 cells and cytotoxic T lymphocytes (CTLs) reduced their trafficking to and survival in tumors and was associated with shorter survival of patients with breast and lung cancer. RGS1 was upregulated by type II interferon (IFN)-signal transducer and activator of transcription (STAT)1 signaling and impaired trafficking of circulating T cells to tumors by inhibiting calcium influx and suppressing activation of the kinases ERK and AKT. RGS1 knockdown in adoptively transferred tumor-specific CTLs significantly increased their infiltration and survival in breast and lung tumor grafts and effectively inhibited tumor growth in vivo, which was further improved when combined with programmed death ligand (PD-L)1 checkpoint inhibition. Our findings reveal RGS1 is important for tumor immune evasion and suggest that targeting RGS1 may provide a new strategy for tumor immunotherapy.
Subject(s)
Breast Neoplasms/metabolism , Carcinoma, Ductal, Breast/metabolism , Chemotaxis, Leukocyte , Lymphocytes, Tumor-Infiltrating/metabolism , RGS Proteins/metabolism , T-Lymphocyte Subsets/metabolism , Animals , Apoptosis , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Breast Neoplasms/therapy , Carcinoma, Ductal, Breast/immunology , Carcinoma, Ductal, Breast/pathology , Carcinoma, Ductal, Breast/therapy , Cell Line, Tumor , Chemokines/metabolism , Coculture Techniques , Cytotoxicity, Immunologic , Female , Humans , Immunotherapy, Adoptive , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/transplantation , Mice, Inbred BALB C , Mice, Inbred C57BL , Microscopy, Fluorescence , Microscopy, Video , RGS Proteins/genetics , Signal Transduction , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/transplantation , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , Th1 Cells/immunology , Th1 Cells/metabolism , Time Factors , Time-Lapse Imaging , Tumor Cells, Cultured , Tumor EscapeABSTRACT
Stroke leads to persistently high risk for recurrent vascular events caused by systemic atheroprogression that is driven by endothelial cell (EC) activation. However, whether and how stroke induces sustained pro-inflammatory and proatherogenic endothelial alterations in systemic vessels remain poorly understood. We showed that brain ischemia induces persistent activation, the upregulation of adhesion molecule VCAM1, and increased senescence in peripheral ECs until 4 weeks after stroke onset. This aberrant EC activity resulted from sustained Notch1 signaling, which was triggered by increased circulating Notch1 ligands DLL1 and Jagged1 after stroke in mice and humans. Consequently, this led to increased myeloid cell adhesion and atheroprogression by generating a senescent, pro-inflammatory endothelium. Notch1- or VCAM1-blocking antibodies and the genetic ablation of endothelial Notch1 reduced atheroprogression after stroke. Our findings revealed a systemic machinery that induces the persistent activation of peripheral ECs after stroke, which paves the way for therapeutic interventions or the prevention of recurrent vascular events following stroke.
ABSTRACT
Neurons in Caenorhabditis elegans and other nematodes have been thought to lack classical action potentials. Unexpectedly, we observe membrane potential spikes with defining characteristics of action potentials in C. elegans AWA olfactory neurons recorded under current-clamp conditions. Ion substitution experiments, mutant analysis, pharmacology, and modeling indicate that AWA fires calcium spikes, which are initiated by EGL-19 voltage-gated CaV1 calcium channels and terminated by SHK-1 Shaker-type potassium channels. AWA action potentials result in characteristic signals in calcium imaging experiments. These calcium signals are also observed when intact animals are exposed to odors, suggesting that natural odor stimuli induce AWA spiking. The stimuli that elicit action potentials match AWA's specialized function in climbing odor gradients. Our results provide evidence that C. elegans neurons can encode information through regenerative all-or-none action potentials, expand the computational repertoire of its nervous system, and inform future modeling of its neural coding and network dynamics.
Subject(s)
Action Potentials/physiology , Olfactory Nerve/physiology , Smell/physiology , Animals , Caenorhabditis elegans/physiology , Caenorhabditis elegans Proteins/metabolism , Calcium/metabolism , Calcium Channels/physiology , Chemotaxis/physiology , Membrane Potentials/physiology , Odorants , Olfactory Receptor Neurons/metabolismABSTRACT
Antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) critically contribute to the efficacy of anti-tumor therapeutic antibodies. We report here an unexpected finding that macrophages after ADCP inhibit NK cell-mediated ADCC and T cell-mediated cytotoxicity in breast cancers and lymphomas. Mechanistically, AIM2 is recruited to the phagosomes by FcγR signaling following ADCP and activated by sensing the phagocytosed tumor DNAs through the disrupted phagosomal membrane, which subsequently upregulates PD-L1 and IDO and causes immunosuppression. Combined treatment with anti-HER2 antibody and inhibitors of PD-L1 and IDO enhances anti-tumor immunity and anti-HER2 therapeutic efficacy in mouse models. Furthermore, neoadjuvant trastuzumab therapy significantly upregulates PD-L1 and IDO in the tumor-associated macrophages (TAMs) of HER2+ breast cancer patients, correlating with poor trastuzumab response. Collectively, our findings unveil a deleterious role of ADCP macrophages in cancer immunosuppression and suggest that therapeutic antibody plus immune checkpoint blockade may provide synergistic effects in cancer treatment.
Subject(s)
Antibody-Dependent Cell Cytotoxicity/immunology , Cytophagocytosis/immunology , Macrophages/immunology , Animals , Antibodies, Monoclonal/therapeutic use , Antibody-Dependent Cell Cytotoxicity/physiology , B7-H1 Antigen/genetics , B7-H1 Antigen/physiology , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Cell Line, Tumor , Cytophagocytosis/physiology , DNA-Binding Proteins/physiology , Disease Models, Animal , Female , Humans , Immunotherapy , Killer Cells, Natural/physiology , Lymphoma/immunology , Macrophages/physiology , Mice , Mice, Inbred NOD , Mice, SCID , Phagocytosis/immunology , Phagocytosis/physiology , Phagosomes/physiology , Receptors, IgG/immunologyABSTRACT
Carcinoma-associated fibroblasts (CAFs) are abundant and heterogeneous stromal cells in tumor microenvironment that are critically involved in cancer progression. Here, we demonstrate that two cell-surface molecules, CD10 and GPR77, specifically define a CAF subset correlated with chemoresistance and poor survival in multiple cohorts of breast and lung cancer patients. CD10+GPR77+ CAFs promote tumor formation and chemoresistance by providing a survival niche for cancer stem cells (CSCs). Mechanistically, CD10+GPR77+ CAFs are driven by persistent NF-κB activation via p65 phosphorylation and acetylation, which is maintained by complement signaling via GPR77, a C5a receptor. Furthermore, CD10+GPR77+ CAFs promote successful engraftment of patient-derived xenografts (PDXs), and targeting these CAFs with a neutralizing anti-GPR77 antibody abolishes tumor formation and restores tumor chemosensitivity. Our study reveals a functional CAF subset that can be defined and isolated by specific cell-surface markers and suggests that targeting the CD10+GPR77+ CAF subset could be an effective therapeutic strategy against CSC-driven solid tumors.
Subject(s)
Cell Transformation, Neoplastic/immunology , Drug Resistance, Neoplasm/immunology , Fibroblasts/immunology , Neoplasms/immunology , Neoplastic Stem Cells/immunology , Neprilysin/immunology , Receptors, Chemokine/immunology , Tumor Microenvironment/immunology , A549 Cells , Cell Transformation, Neoplastic/pathology , Fibroblasts/pathology , Humans , MCF-7 Cells , Neoplasm Proteins/immunology , Neoplasms/pathology , Neoplastic Stem Cells/pathology , Receptor, Anaphylatoxin C5aABSTRACT
We analyze whole-genome sequencing data from 141,431 Chinese women generated for non-invasive prenatal testing (NIPT). We use these data to characterize the population genetic structure and to investigate genetic associations with maternal and infectious traits. We show that the present day distribution of alleles is a function of both ancient migration and very recent population movements. We reveal novel phenotype-genotype associations, including several replicated associations with height and BMI, an association between maternal age and EMB, and between twin pregnancy and NRG1. Finally, we identify a unique pattern of circulating viral DNA in plasma with high prevalence of hepatitis B and other clinically relevant maternal infections. A GWAS for viral infections identifies an exceptionally strong association between integrated herpesvirus 6 and MOV10L1, which affects piwi-interacting RNA (piRNA) processing and PIWI protein function. These findings demonstrate the great value and potential of accumulating NIPT data for worldwide medical and genetic analyses.
Subject(s)
Asian People/genetics , Prenatal Diagnosis/methods , Adult , Alleles , China , DNA/genetics , Ethnicity/genetics , Female , Gene Frequency/genetics , Genetic Testing , Genetic Variation/genetics , Genetics, Population/methods , Genome-Wide Association Study/methods , Genomics/methods , Human Migration , Humans , Pregnancy , Sequence Analysis, DNAABSTRACT
Neuronal signals have emerged as pivotal regulators of group 2 innate lymphoid cells (ILC2s) that regulate tissue homeostasis and allergic inflammation. The molecular pathways underlying the neuronal regulation of ILC2 responses in lungs remain to be fully elucidated. Here, we found that the abundance of neurotransmitter dopamine was negatively correlated with circulating ILC2 numbers and positively associated with pulmonary function in humans. Dopamine potently suppressed lung ILC2 responses in a DRD1-receptor-dependent manner. Genetic deletion of Drd1 or local ablation of dopaminergic neurons augmented ILC2 responses and allergic lung inflammation. Transcriptome and metabolic analyses revealed that dopamine impaired the mitochondrial oxidative phosphorylation (OXPHOS) pathway in ILC2s. Augmentation of OXPHOS activity with oltipraz antagonized the inhibitory effect of dopamine. Local administration of dopamine alleviated allergen-induced ILC2 responses and airway inflammation. These findings demonstrate that dopamine represents an inhibitory regulator of ILC2 responses in allergic airway inflammation.
Subject(s)
Immunity, Innate , Pneumonia , Humans , Dopamine/metabolism , Lymphocytes , Lung/metabolism , Pneumonia/metabolism , Inflammation/metabolism , Interleukin-33/metabolismABSTRACT
The endomembrane system consists of organellar membranes in the biosynthetic pathway [endoplasmic reticulum (ER), Golgi apparatus, and secretory vesicles] as well as those in the degradative pathway (early endosomes, macropinosomes, phagosomes, autophagosomes, late endosomes, and lysosomes). These endomembrane organelles/vesicles work together to synthesize, modify, package, transport, and degrade proteins, carbohydrates, and lipids, regulating the balance between cellular anabolism and catabolism. Large ion concentration gradients exist across endomembranes: Ca2+ gradients for most endomembrane organelles and H+ gradients for the acidic compartments. Ion (Na+, K+, H+, Ca2+, and Cl-) channels on the organellar membranes control ion flux in response to cellular cues, allowing rapid informational exchange between the cytosol and organelle lumen. Recent advances in organelle proteomics, organellar electrophysiology, and luminal and juxtaorganellar ion imaging have led to molecular identification and functional characterization of about two dozen endomembrane ion channels. For example, whereas IP3R1-3 channels mediate Ca2+ release from the ER in response to neurotransmitter and hormone stimulation, TRPML1-3 and TMEM175 channels mediate lysosomal Ca2+ and H+ release, respectively, in response to nutritional and trafficking cues. This review aims to summarize the current understanding of these endomembrane channels, with a focus on their subcellular localizations, ion permeation properties, gating mechanisms, cell biological functions, and disease relevance.
Subject(s)
Ion Channels , Humans , Animals , Ion Channels/metabolism , Intracellular Membranes/metabolism , Organelles/metabolism , Organelles/physiologyABSTRACT
Activation-induced cell death (AICD) of T lymphocytes can be exploited by cancers to escape immunological destruction. We demonstrated that tumor-specific cytotoxic T lymphocytes (CTLs) and type 1 helper T (TH1) cells, rather than type 2 helper T cells and regulatory T cells, were sensitive to AICD in breast and lung cancer microenvironments. NKILA, an NF-κB-interacting long noncoding RNA (lncRNA), regulates T cell sensitivity to AICD by inhibiting NF-κB activity. Mechanistically, calcium influx in stimulated T cells via T cell-receptor signaling activates calmodulin, thereby removing deacetylase from the NKILA promoter and enhancing STAT1-mediated transcription. Administering CTLs with NKILA knockdown effectively inhibited growth of breast cancer patient-derived xenografts in mice by increasing CTL infiltration. Clinically, NKILA overexpression in tumor-specific CTLs and TH1 cells correlated with their apoptosis and shorter patient survival. Our findings underscore the importance of lncRNAs in determining tumor-mediated T cell AICD and suggest that engineering lncRNAs in adoptively transferred T cells might provide a novel antitumor immunotherapy.
Subject(s)
Carcinoma/immunology , RNA, Long Noncoding/immunology , T-Lymphocytes, Cytotoxic/immunology , Th1 Cells/immunology , Tumor Escape/genetics , Animals , Apoptosis/immunology , Breast Neoplasms/genetics , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Carcinoma/genetics , Carcinoma/pathology , Female , Heterografts , Humans , Lung Neoplasms/genetics , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Male , Mice, Inbred NOD , Mice, SCID , RNA, Long Noncoding/geneticsABSTRACT
Asymmetric catalysis enables the synthesis of optically active compounds, often requiring the differentiation between two substituents on prochiral substrates1. Despite decades of development of mainly noble metal catalysts, achieving differentiation between substituents with similar steric and electronic properties remains a notable challenge2,3. Here we introduce a class of Earth-abundant manganese catalysts for the asymmetric hydrogenation of dialkyl ketimines to give a range of chiral amine products. These catalysts distinguish between pairs of minimally differentiated alkyl groups bound to the ketimine, such as methyl and ethyl, and even subtler distinctions, such as ethyl and n-propyl. The degree of enantioselectivity can be adjusted by modifying the components of the chiral manganese catalyst. This reaction demonstrates a wide substrate scope and achieves a turnover number of up to 107,800. Our mechanistic studies indicate that exceptional stereoselectivity arises from the modular assembly of confined chiral catalysts and cooperative non-covalent interactions between the catalyst and the substrate.
Subject(s)
Chemistry Techniques, Synthetic , Hydrogenation , Imines , Nitriles , Stereoisomerism , Amines/chemistry , Amines/chemical synthesis , Catalysis , Imines/chemistry , Manganese/chemistry , Nitriles/chemistry , Pharmaceutical Preparations/chemical synthesis , Pharmaceutical Preparations/chemistry , Substrate Specificity , AlkylationABSTRACT
ADP-ribose (ADPr) readers are essential components of ADP-ribosylation signaling, which regulates genome maintenance and immunity. The identification and discrimination between monoADPr (MAR) and polyADPr (PAR) readers is difficult because of a lack of suitable affinity-enrichment reagents. We synthesized well-defined ADPr probes and used these for affinity purifications combined with relative and absolute quantitative mass spectrometry to generate proteome-wide MAR and PAR interactomes, including determination of apparent binding affinities. Among the main findings, MAR and PAR readers regulate various common and distinct processes, such as the DNA-damage response, cellular metabolism, RNA trafficking, and transcription. We monitored the dynamics of PAR interactions upon induction of oxidative DNA damage and uncovered the mechanistic connections between ubiquitin signaling and ADP-ribosylation. Taken together, chemical biology enables exploration of MAR and PAR readers using interaction proteomics. Furthermore, the generated MAR and PAR interaction maps significantly expand our current understanding of ADPr signaling.
Subject(s)
ADP-Ribosylation , Adenosine Diphosphate Ribose/chemistry , Adenosine Diphosphate/chemistry , Proteomics/methods , Ubiquitin-Protein Ligases/chemistry , Allosteric Site , Animals , Antibodies, Monoclonal/chemistry , Binding Sites , Biotinylation , Cell Communication , DNA Damage , Genetic Techniques , HeLa Cells , Humans , Mass Spectrometry , Mice , Protein Binding , Protein Processing, Post-Translational , Proteome , Signal Transduction , UbiquitinABSTRACT
U1 snRNP (U1), in addition to its splicing role, protects pre-mRNAs from drastic premature termination by cleavage and polyadenylation (PCPA) at cryptic polyadenylation signals (PASs) in introns. Here, a high-throughput sequencing strategy of differentially expressed transcripts (HIDE-seq) mapped PCPA sites genome wide in divergent organisms. Surprisingly, whereas U1 depletion terminated most nascent gene transcripts within ~1 kb, moderate functional U1 level decreases, insufficient to inhibit splicing, dose-dependently shifted PCPA downstream and elicited mRNA 3' UTR shortening and proximal 3' exon switching characteristic of activated immune and neuronal cells, stem cells, and cancer. Activated neurons' signature mRNA shortening could be recapitulated by U1 decrease and antagonized by U1 overexpression. Importantly, we show that rapid and transient transcriptional upregulation inherent to neuronal activation physiology creates U1 shortage relative to pre-mRNAs. Additional experiments suggest cotranscriptional PCPA counteracted by U1 association with nascent transcripts, a process we term telescripting, ensuring transcriptome integrity and regulating mRNA length.
Subject(s)
RNA Precursors/metabolism , Ribonucleoprotein, U1 Small Nuclear/metabolism , Animals , Cell Line , Drosophila melanogaster , Genome-Wide Association Study , HeLa Cells , High-Throughput Nucleotide Sequencing , Humans , Mice , NIH 3T3 Cells , Neurons/metabolism , RNA 3' End Processing , RNA SplicingABSTRACT
The circadian clock throughout the day organizes the activity of neural stem cells (NSCs) in the dentate gyrus (DG) of adult hippocampus temporally. However, it is still unclear whether and how circadian signals from the niches contribute to daily rhythmic variation of NSC activation. Here, we show that norepinephrinergic (NEergic) projections from the locus coeruleus (LC), a brain arousal system, innervate into adult DG, where daily rhythmic release of norepinephrine (NE) from the LC NEergic neurons controlled circadian variation of NSC activation through ß3-adrenoceptors. Disrupted circadian rhythmicity by acute sleep deprivation leads to transient NSC overactivation and NSC pool exhaustion over time, which is effectively ameliorated by the inhibition of the LC NEergic neuronal activity or ß3-adrenoceptors-mediated signaling. Finally, we demonstrate that NE/ß3-adrenoceptors-mediated signaling regulates NSC activation through molecular clock BMAL1. Therefore, our study unravels that adult NSCs precisely coordinate circadian neural circuit and intrinsic molecular circadian clock to adapt their cellular behavior across the day.
Subject(s)
Circadian Clocks , Neural Stem Cells , Humans , Adult , Circadian Rhythm/physiology , Hippocampus , Circadian Clocks/physiology , Receptors, AdrenergicABSTRACT
Staphylococcus aureus (S. aureus) can evade antibiotics and host immune defenses by persisting within infected cells. Here, we demonstrate that in infected host cells, S. aureus type VII secretion system (T7SS) extracellular protein B (EsxB) interacts with the stimulator of interferon genes (STING) protein and suppresses the inflammatory defense mechanism of macrophages during early infection. The binding of EsxB with STING disrupts the K48-linked ubiquitination of EsxB at lysine 33, thereby preventing EsxB degradation. Furthermore, EsxB-STING binding appears to interrupt the interaction of 2 vital regulatory proteins with STING: aspartate-histidine-histidine-cysteine domain-containing protein 3 (DHHC3) and TNF receptor-associated factor 6. This persistent dual suppression of STING interactions deregulates intracellular proinflammatory pathways in macrophages, inhibiting STING's palmitoylation at cysteine 91 and its K63-linked ubiquitination at lysine 83. These findings uncover an immune-evasion mechanism by S. aureus T7SS during intracellular macrophage infection, which has implications for developing effective immunomodulators to combat S. aureus infections.
Subject(s)
Bacterial Proteins , Macrophages , Membrane Proteins , Staphylococcal Infections , Staphylococcus aureus , Type VII Secretion Systems , Ubiquitination , Staphylococcus aureus/immunology , Membrane Proteins/metabolism , Membrane Proteins/immunology , Humans , Bacterial Proteins/metabolism , Bacterial Proteins/immunology , Macrophages/immunology , Macrophages/metabolism , Macrophages/microbiology , Animals , Staphylococcal Infections/immunology , Staphylococcal Infections/microbiology , Staphylococcal Infections/metabolism , Type VII Secretion Systems/metabolism , Type VII Secretion Systems/immunology , Type VII Secretion Systems/genetics , Mice , Immune Evasion , Host-Pathogen Interactions/immunologyABSTRACT
Brain ischemia inhibits immune function systemically, with resulting infectious complications. Whether in stroke different immune alterations occur in brain and periphery and whether analogous mechanisms operate in these compartments remains unclear. Here we show that in patients with ischemic stroke and in mice subjected to middle cerebral artery occlusion, natural killer (NK) cells display remarkably distinct temporal and transcriptome profiles in the brain as compared to the periphery. The activation of catecholaminergic and hypothalamic-pituitary-adrenal axis leads to splenic atrophy and contraction of NK cell numbers in the periphery through a modulated expression of SOCS3, whereas cholinergic innervation-mediated suppression of NK cell responses in the brain involves RUNX3. Importantly, pharmacological or genetic ablation of innervation preserved NK cell function and restrained post-stroke infection. Thus, brain ischemia compromises NK cell-mediated immune defenses through mechanisms that differ in the brain versus the periphery, and targeted inhibition of neurogenic innervation limits post-stroke infection.
Subject(s)
Brain Ischemia/immunology , Brain/immunology , Killer Cells, Natural/immunology , Spleen/immunology , Aged , Animals , Brain Ischemia/complications , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Gene Expression Profiling , Humans , Infections/etiology , Infections/immunology , Male , Mice , Mice, Inbred C57BL , Real-Time Polymerase Chain Reaction , TranscriptomeABSTRACT
Neutrophil extracellular traps (NETs), which consist of chromatin DNA filaments coated with granule proteins, are released by neutrophils to trap microorganisms1-3. Recent studies have suggested that the DNA component of NETs (NET-DNA) is associated with cancer metastasis in mouse models4-6. However, the functional role and clinical importance of NET-DNA in metastasis in patients with cancer remain unclear. Here we show that NETs are abundant in the liver metastases of patients with breast and colon cancers, and that serum NETs can predict the occurrence of liver metastases in patients with early-stage breast cancer. NET-DNA acts as a chemotactic factor to attract cancer cells, rather than merely acting as a 'trap' for them; in several mouse models, NETs in the liver or lungs were found to attract cancer cells to form distant metastases. We identify the transmembrane protein CCDC25 as a NET-DNA receptor on cancer cells that senses extracellular DNA and subsequently activates the ILK-ß-parvin pathway to enhance cell motility. NET-mediated metastasis is abrogated in CCDC25-knockout cells. Clinically, we show that the expression of CCDC25 on primary cancer cells is closely associated with a poor prognosis for patients. Overall, we describe a transmembrane DNA receptor that mediates NET-dependent metastasis, and suggest that targeting CCDC25 could be an appealing therapeutic strategy for the prevention of cancer metastasis.
Subject(s)
Breast Neoplasms/pathology , DNA/metabolism , Extracellular Traps/genetics , Membrane Proteins/metabolism , Neoplasm Metastasis/genetics , Neoplasm Metastasis/pathology , Neutrophils/metabolism , Actinin/metabolism , Animals , Cell Line, Tumor , Cell Movement , Female , Humans , Liver/pathology , Liver Neoplasms/pathology , Liver Neoplasms/secondary , Membrane Proteins/genetics , Mice , Prognosis , Protein Serine-Threonine Kinases/metabolism , Signal TransductionABSTRACT
The ability of superhydrophobic surfaces to stay dry, self-clean and avoid biofouling is attractive for applications in biotechnology, medicine and heat transfer1-10. Water droplets that contact these surfaces must have large apparent contact angles (greater than 150 degrees) and small roll-off angles (less than 10 degrees). This can be realized for surfaces that have low-surface-energy chemistry and micro- or nanoscale surface roughness, minimizing contact between the liquid and the solid surface11-17. However, rough surfaces-for which only a small fraction of the overall area is in contact with the liquid-experience high local pressures under mechanical load, making them fragile and highly susceptible to abrasion18. Additionally, abrasion exposes underlying materials and may change the local nature of the surface from hydrophobic to hydrophilic19, resulting in the pinning of water droplets to the surface. It has therefore been assumed that mechanical robustness and water repellency are mutually exclusive surface properties. Here we show that robust superhydrophobicity can be realized by structuring surfaces at two different length scales, with a nanostructure design to provide water repellency and a microstructure design to provide durability. The microstructure is an interconnected surface frame containing 'pockets' that house highly water-repellent and mechanically fragile nanostructures. This surface frame acts as 'armour', preventing the removal of the nanostructures by abradants that are larger than the frame size. We apply this strategy to various substrates-including silicon, ceramic, metal and transparent glass-and show that the water repellency of the resulting superhydrophobic surfaces is preserved even after abrasion by sandpaper and by a sharp steel blade. We suggest that this transparent, mechanically robust, self-cleaning glass could help to negate the dust-contamination issue that leads to a loss of efficiency in solar cells. Our design strategy could also guide the development of other materials that need to retain effective self-cleaning, anti-fouling or heat-transfer abilities in harsh operating environments.
Subject(s)
Hydrophobic and Hydrophilic Interactions , Surface Properties , Biofouling/prevention & control , Water/chemistryABSTRACT
Nearly half of the elements in the periodic table are extracted, refined, or plated using electrodeposition in high-temperature melts. However, operando observations and tuning of the electrodeposition process during realistic electrolysis operations are extremely difficult due to severe reaction conditions and complicated electrolytic cell, which makes the improvement of the process very blind and inefficient. Here, we developed a multipurpose operando high-temperature electrochemical instrument that combines operando Raman microspectroscopy analysis, optical microscopy imaging, and a tunable magnetic field. Subsequently, the electrodeposition of Ti-which is a typical polyvalent metal and generally shows a very complex electrode process-was used to verify the stability of the instrument. The complex multistep cathodic process of Ti in the molten salt at 823 K was systematically analyzed by a multidimensional operando analysis strategy involving multiple experimental studies, theoretical calculations, etc. The regulatory effect and its corresponding scale-span mechanism of the magnetic field on the electrodeposition process of Ti were also elucidated, which would be inaccessible with existing experimental techniques and is significant for the real-time and rational optimization of the process. Overall, this work established a powerful and universal methodology for in-depth analysis of high-temperature electrochemistry.