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1.
Nature ; 629(8012): 579-585, 2024 May.
Article in English | MEDLINE | ID: mdl-38750235

ABSTRACT

Towards realizing the future quantum internet1,2, a pivotal milestone entails the transition from two-node proof-of-principle experiments conducted in laboratories to comprehensive multi-node set-ups on large scales. Here we report the creation of memory-memory entanglement in a multi-node quantum network over a metropolitan area. We use three independent memory nodes, each of which is equipped with an atomic ensemble quantum memory3 that has telecom conversion, together with a photonic server where detection of a single photon heralds the success of entanglement generation. The memory nodes are maximally separated apart for 12.5 kilometres. We actively stabilize the phase variance owing to fibre links and control lasers. We demonstrate concurrent entanglement generation between any two memory nodes. The memory lifetime is longer than the round-trip communication time. Our work provides a metropolitan-scale testbed for the evaluation and exploration of multi-node quantum network protocols and starts a stage of quantum internet research.

2.
Immunity ; 52(5): 767-781.e6, 2020 05 19.
Article in English | MEDLINE | ID: mdl-32277911

ABSTRACT

The enzyme cyclic GMP-AMP synthase (cGAS) senses cytosolic DNA in infected and malignant cells and catalyzes the formation of 2'3'cGMP-AMP (cGAMP), which in turn triggers interferon (IFN) production via the STING pathway. Here, we examined the contribution of anion channels to cGAMP transfer and anti-viral defense. A candidate screen revealed that inhibition of volume-regulated anion channels (VRACs) increased propagation of the DNA virus HSV-1 but not the RNA virus VSV. Chemical blockade or genetic ablation of LRRC8A/SWELL1, a VRAC subunit, resulted in defective IFN responses to HSV-1. Biochemical and electrophysiological analyses revealed that LRRC8A/LRRC8E-containing VRACs transport cGAMP and cyclic dinucleotides across the plasma membrane. Enhancing VRAC activity by hypotonic cell swelling, cisplatin, GTPγS, or the cytokines TNF or interleukin-1 increased STING-dependent IFN response to extracellular but not intracellular cGAMP. Lrrc8e-/- mice exhibited impaired IFN responses and compromised immunity to HSV-1. Our findings suggest that cell-to-cell transmission of cGAMP via LRRC8/VRAC channels is central to effective anti-viral immunity.


Subject(s)
Fibroblasts/immunology , Interferons/immunology , Membrane Proteins/immunology , Nucleotides, Cyclic/immunology , Voltage-Dependent Anion Channels/immunology , Animals , Antiviral Agents/immunology , Antiviral Agents/metabolism , Bystander Effect , Cell Line , Cells, Cultured , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Fibroblasts/cytology , Fibroblasts/metabolism , HeLa Cells , Herpes Simplex/immunology , Herpes Simplex/virology , Herpesvirus 1, Human/immunology , Herpesvirus 1, Human/physiology , Humans , Interferons/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice, Inbred C57BL , Mice, Knockout , Nucleotides, Cyclic/metabolism , Nucleotidyltransferases/genetics , Nucleotidyltransferases/immunology , Nucleotidyltransferases/metabolism , Voltage-Dependent Anion Channels/metabolism
3.
Nat Immunol ; 16(6): 642-52, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25915733

ABSTRACT

Fungal infection stimulates the canonical C-type lectin receptor (CLR) signaling pathway via activation of the tyrosine kinase Syk. Here we identify a crucial role for the tyrosine phosphatase SHP-2 in mediating CLR-induced activation of Syk. Ablation of the gene encoding SHP-2 (Ptpn11; called 'Shp-2' here) in dendritic cells (DCs) and macrophages impaired Syk-mediated signaling and abrogated the expression of genes encoding pro-inflammatory molecules following fungal stimulation. Mechanistically, SHP-2 operated as a scaffold, facilitating the recruitment of Syk to the CLR dectin-1 or the adaptor FcRγ, through its N-SH2 domain and a previously unrecognized carboxy-terminal immunoreceptor tyrosine-based activation motif (ITAM). We found that DC-derived SHP-2 was crucial for the induction of interleukin 1ß (IL-1ß), IL-6 and IL-23 and anti-fungal responses of the TH17 subset of helper T cells in controlling infection with Candida albicans. Together our data reveal a mechanism by which SHP-2 mediates the activation of Syk in response to fungal infection.


Subject(s)
Candidiasis/immunology , Dendritic Cells/physiology , Intracellular Signaling Peptides and Proteins/metabolism , Macrophages/physiology , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Protein-Tyrosine Kinases/metabolism , T-Lymphocytes, Helper-Inducer/immunology , Th17 Cells/immunology , Amino Acid Motifs/genetics , Animals , Antigens, Fungal/immunology , Cells, Cultured , Cytokines/metabolism , Enzyme Activation , Inflammation Mediators/metabolism , Lectins, C-Type/genetics , Lectins, C-Type/metabolism , Lymphocyte Activation , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Mutation/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics , Receptors, IgE/genetics , Receptors, IgE/metabolism , Signal Transduction , Syk Kinase
4.
Am J Hum Genet ; 110(7): 1162-1176, 2023 07 06.
Article in English | MEDLINE | ID: mdl-37352861

ABSTRACT

Large-scale genetic association studies have identified multiple susceptibility loci for nasopharyngeal carcinoma (NPC), but the underlying biological mechanisms remain to be explored. To gain insights into the genetic etiology of NPC, we conducted a follow-up study encompassing 6,907 cases and 10,472 controls and identified two additional NPC susceptibility loci, 9q22.33 (rs1867277; OR = 0.74, 95% CI = 0.68-0.81, p = 3.08 × 10-11) and 17q12 (rs226241; OR = 1.42, 95% CI = 1.26-1.60, p = 1.62 × 10-8). The two additional loci, together with two previously reported genome-wide significant loci, 5p15.33 and 9p21.3, were investigated by high-throughput sequencing for chromatin accessibility, histone modification, and promoter capture Hi-C (PCHi-C) profiling. Using luciferase reporter assays and CRISPR interference (CRISPRi) to validate the functional profiling, we identified PHF2 at locus 9q22.33 as a susceptibility gene. PHF2 encodes a histone demethylase and acts as a tumor suppressor. The risk alleles of the functional SNPs reduced the expression of the target gene PHF2 by inhibiting the enhancer activity of its long-range (4.3 Mb) cis-regulatory element, which promoted proliferation of NPC cells. In addition, we identified CDKN2B-AS1 as a susceptibility gene at locus 9p21.3, and the NPC risk allele of the functional SNP rs2069418 promoted the expression of CDKN2B-AS1 by increasing its enhancer activity. The overexpression of CDKN2B-AS1 facilitated proliferation of NPC cells. In summary, we identified functional SNPs and NPC susceptibility genes, which provides additional explanations for the genetic association signals and helps to uncover the underlying genetic etiology of NPC development.


Subject(s)
Nasopharyngeal Neoplasms , Humans , Nasopharyngeal Carcinoma/genetics , Nasopharyngeal Neoplasms/genetics , Nasopharyngeal Neoplasms/pathology , Follow-Up Studies , Genetic Predisposition to Disease , Genetic Association Studies , Polymorphism, Single Nucleotide/genetics , Homeodomain Proteins/genetics
5.
J Immunol ; 213(3): 347-361, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38847616

ABSTRACT

The cyclic GMP-AMP synthase (cGAS)-stimulator of IFN genes (STING) pathway is instrumental to antitumor immunity, yet the underlying molecular and cellular mechanisms are complex and still unfolding. A new paradigm suggests that cancer cells' cGAS-synthesized cGAMP can be transferred to tumor-infiltrating immune cells, eliciting STING-dependent IFN-ß response for antitumor immunity. Nevertheless, how the tumor microenvironment may shape this process remains unclear. In this study, we found that extracellular ATP, an immune regulatory molecule widely present in the tumor microenvironment, can potentiate cGAMP transfer, thereby boosting the STING signaling and IFN-ß response in murine macrophages and fibroblasts. Notably, genetic ablation or chemical inhibition of murine volume-regulation anion channel LRRC8/volume-regulated anion channel (VRAC), a recently identified cGAMP transporter, abolished ATP-potentiated cGAMP transfer and STING-dependent IFN-ß response, revealing a crucial role of LRRC8/VRAC in the cross-talk of extracellular ATP and cGAMP. Mechanistically, ATP activation of the P2X family receptors triggered Ca2+ influx and K+ efflux, promoting reactive oxygen species production. Moreover, ATP-evoked K+ efflux alleviated the phosphorylation of VRAC's obligate subunit LRRC8A/SWELL1 on S174. Mutagenesis studies indicated that the phosphorylation of S174 on LRRC8A could act as a checkpoint for VRAC in the steady state and a rheostat of ATP responsiveness. In an MC38-transplanted tumor model, systemically blocking CD39 and ENPP1, hydroxylases of extracellular ATP and cGAMP, respectively, elevated antitumor NK, NKT, and CD8+ T cell responses and restrained tumor growth in mice. Altogether, this study establishes a crucial role of ATP in facilitating LRRC8/VRAC transport cGAMP in the tumor microenvironment and provides new insight into harnessing cGAMP transfer for antitumor immunity.


Subject(s)
Adenosine Triphosphate , Membrane Proteins , Nucleotides, Cyclic , Tumor Microenvironment , Animals , Nucleotides, Cyclic/metabolism , Mice , Adenosine Triphosphate/metabolism , Membrane Proteins/metabolism , Membrane Proteins/immunology , Tumor Microenvironment/immunology , Interferon-beta/metabolism , Interferon-beta/immunology , Mice, Inbred C57BL , Humans , Signal Transduction/immunology , Mice, Knockout , Cell Line, Tumor , Cations/metabolism , Neoplasms/immunology , Neoplasms/metabolism , Nucleotidyltransferases/metabolism , Macrophages/immunology , Macrophages/metabolism
6.
Nature ; 578(7794): 240-245, 2020 02.
Article in English | MEDLINE | ID: mdl-32051600

ABSTRACT

A quantum internet that connects remote quantum processors1,2 should enable a number of revolutionary applications such as distributed quantum computing. Its realization will rely on entanglement of remote quantum memories over long distances. Despite enormous progress3-12, at present the maximal physical separation achieved between two nodes is 1.3 kilometres10, and challenges for longer distances remain. Here we demonstrate entanglement of two atomic ensembles in one laboratory via photon transmission through city-scale optical fibres. The atomic ensembles function as quantum memories that store quantum states. We use cavity enhancement to efficiently create atom-photon entanglement13-15 and we use quantum frequency conversion16 to shift the atomic wavelength to telecommunications wavelengths. We realize entanglement over 22 kilometres of field-deployed fibres via two-photon interference17,18 and entanglement over 50 kilometres of coiled fibres via single-photon interference19. Our experiment could be extended to nodes physically separated by similar distances, which would thus form a functional segment of the atomic quantum network, paving the way towards establishing atomic entanglement over many nodes and over much longer distances.

7.
Proc Natl Acad Sci U S A ; 120(8): e2210643120, 2023 02 21.
Article in English | MEDLINE | ID: mdl-36795751

ABSTRACT

Microglia play a critical role in the pathogenic process of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer's disease (AD). Upon pathological stimulation, microglia are converted from a surveillant to an overactivated phenotype. However, the molecular characters of proliferating microglia and their contributions to the pathogenesis of neurodegeneration remain unclear. Here, we identify chondroitin sulfate proteoglycan 4 (Cspg4, also known as neural/glial antigen 2)-expressing microglia as a specific subset of microglia with proliferative capability during neurodegeneration. We found that the percentage of Cspg4+ microglia was increased in mouse models of PD. The transcriptomic analysis of Cspg4+ microglia revealed that the subcluster Cspg4high microglia displayed a unique transcriptomic signature, which was characterized by the enrichment of orthologous cell cycle genes and a lower expression of genes responsible for neuroinflammation and phagocytosis. Their gene signatures were also distinct from that of known disease-associated microglia. The proliferation of quiescent Cspg4high microglia was evoked by pathological α-synuclein. Following the transplantation in the adult brain with the depletion of endogenous microglia, Cspg4high microglia grafts showed higher survival rates than their Cspg4- counterparts. Consistently, Cspg4high microglia were detected in the brain of AD patients and displayed the expansion in animal models of AD. These findings suggest that Cspg4high microglia are one of the origins of microgliosis during neurodegeneration and may open up a avenue for the treatment of neurodegenerative diseases.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Parkinson Disease , Mice , Animals , Microglia/metabolism , Parkinson Disease/metabolism , Alzheimer Disease/metabolism , Neurodegenerative Diseases/metabolism , Phagocytosis
8.
Development ; 149(12)2022 06 15.
Article in English | MEDLINE | ID: mdl-35616329

ABSTRACT

The perinuclear theca (PT) is a cytoskeletal element encapsulating the sperm nucleus; however, the physiological roles of the PT in sperm are largely uncertain. Here, we reveal that ACTRT1, ACTRT2, ACTL7A and ACTL9 proteins interact to form a multimeric complex and localize to the subacrosomal region of spermatids. Furthermore, we engineered Actrt1-knockout (KO) mice to define the functions of ACTRT1. Despite normal sperm count and motility, Actrt1-KO males were severely subfertile owing to a deficiency in fertilization. Loss of ACTRT1 caused a high incidence of malformed heads and detachment of acrosomes from sperm nuclei, caused by loosened acroplaxome structure during spermiogenesis. Furthermore, Actrt1-KO sperm showed reduced ACTL7A and PLCζ protein content as a potential cause of fertilization defects. Moreover, we reveal that ACTRT1 anchors developing acrosomes to the nucleus, likely by interacting with the inner acrosomal membrane protein SPACA1 and the nuclear envelope proteins PARP11 and SPATA46. Loss of ACTRT1 weakened the interaction between ACTL7A and SPACA1. Our study and recent findings of ACTL7A/ACTL9-deficient sperm together reveal that the sperm PT-specific ARP complex mediates the acrosome-nucleus connection.


Subject(s)
Acrosome , Infertility, Male , Acrosome/metabolism , Animals , Humans , Infertility, Male/genetics , Infertility, Male/metabolism , Male , Membrane Proteins/metabolism , Mice , Mice, Knockout , Microfilament Proteins/metabolism , Spermatids/metabolism , Spermatogenesis/genetics , Spermatozoa/metabolism
9.
Nat Immunol ; 14(1): 72-81, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23202271

ABSTRACT

Act1 is an essential adaptor in interleukin 17 (IL-17)-mediated signaling and is recruited to the receptor for IL-17 after stimulation with IL-17. Here we found that Act1 was a 'client' protein of the molecular chaperone hsp90. The D10N variant of Act1 (Act1(D10N)) that is linked to susceptibility to psoriasis was defective in its interaction with hsp90, which resulted in a global loss of Act1 function. Act1-deficient mice modeled the mechanistic link between loss of Act1 function and susceptibility to psoriasis. Although Act1 was necessary for IL-17-mediated inflammation, Act1-deficient mice had a hyperactive response of the T(H)17 subset of helper T cells and developed spontaneous IL-22-dependent skin inflammation. In the absence of IL-17 signaling, IL-22 was the main contributor to skin inflammation, which provides a molecular mechanism for the association of Act1(D10N) with psoriasis susceptibility.


Subject(s)
Connexin 43/metabolism , HSP90 Heat-Shock Proteins/metabolism , Molecular Chaperones/metabolism , Peptide Fragments/metabolism , Psoriasis/immunology , Th17 Cells/immunology , Animals , Cell Line , Connexin 43/genetics , Connexin 43/immunology , Disease Models, Animal , Genetic Predisposition to Disease , Humans , Interleukin-17/metabolism , Mice , Mice, Knockout , Molecular Chaperones/genetics , Mutation/genetics , Peptide Fragments/genetics , Peptide Fragments/immunology , Polymorphism, Genetic , Protein Binding/genetics , Protein Binding/immunology , Psoriasis/genetics , Signal Transduction
10.
Plant Physiol ; 195(3): 1893-1905, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38546393

ABSTRACT

Respiration provides energy, substrates, and precursors to support physiological changes of the fruit during climacteric ripening. A key substrate of respiration is oxygen that needs to be supplied to the fruit in a passive way by gas transfer from the environment. Oxygen gradients may develop within the fruit due to its bulky size and the dense fruit tissues, potentially creating hypoxia that may have a role in the spatial development of ripening. This study presents a 3D reaction-diffusion model using tomato (Solanum lycopersicum) fruit as a test subject, combining the multiscale fruit geometry generated from magnetic resonance imaging and microcomputed tomography with varying respiration kinetics and contrasting boundary resistances obtained through independent experiments. The model predicted low oxygen levels in locular tissue under atmospheric conditions, and the oxygen level was markedly lower upon scar occlusion, aligning with microsensor profiling results. The locular region was in a hypoxic state, leading to its low aerobic respiration with high CO2 accumulation by fermentative respiration, while the rest of the tissues remained well oxygenated. The model further revealed that the hypoxia is caused by a combination of diffusion resistances and respiration rates of the tissue. Collectively, this study reveals the existence of the respiratory gas gradients and its biophysical causes during tomato fruit ripening, providing richer information for future studies on localized endogenous ethylene biosynthesis and fruit ripening.


Subject(s)
Fruit , Oxygen , Solanum lycopersicum , Solanum lycopersicum/growth & development , Solanum lycopersicum/physiology , Solanum lycopersicum/metabolism , Fruit/growth & development , Fruit/physiology , Oxygen/metabolism , Diffusion , Models, Biological , Cell Respiration , Magnetic Resonance Imaging/methods , X-Ray Microtomography
11.
Cell Mol Life Sci ; 81(1): 65, 2024 Jan 28.
Article in English | MEDLINE | ID: mdl-38281222

ABSTRACT

Loss of GLI-Similar 3 (GLIS3) function in mice and humans causes congenital hypothyroidism (CH). In this study, we demonstrate that GLIS3 protein is first detectable at E15.5 of murine thyroid development, a time at which GLIS3 target genes, such as Slc5a5 (Nis), become expressed. This, together with observations showing that ubiquitous Glis3KO mice do not display major changes in prenatal thyroid gland morphology, indicated that CH in Glis3KO mice is due to dyshormonogenesis rather than thyroid dysgenesis. Analysis of GLIS3 in postnatal thyroid suggested a link between GLIS3 protein expression and blood TSH levels. This was supported by data showing that treatment with TSH, cAMP, or adenylyl cyclase activators or expression of constitutively active PKA enhanced GLIS3 protein stability and transcriptional activity, indicating that GLIS3 activity is regulated at least in part by TSH/TSHR-mediated activation of PKA. The TSH-dependent increase in GLIS3 transcriptional activity would be critical for the induction of GLIS3 target gene expression, including several thyroid hormone (TH) biosynthetic genes, in thyroid follicular cells of mice fed a low iodine diet (LID) when blood TSH levels are highly elevated. Like TH biosynthetic genes, the expression of cell cycle genes is suppressed in ubiquitous Glis3KO mice fed a LID; however, in thyroid-specific Glis3 knockout mice, the expression of cell cycle genes was not repressed, in contrast to TH biosynthetic genes. This indicated that the inhibition of cell cycle genes in ubiquitous Glis3KO mice is dependent on changes in gene expression in GLIS3 target tissues other than the thyroid.


Subject(s)
Thyroid Gland , Transcription Factors , Animals , Mice , DNA-Binding Proteins/genetics , Gene Expression Regulation , Repressor Proteins/genetics , Thyroid Gland/metabolism , Thyroid Hormones/metabolism , Thyrotropin/genetics , Thyrotropin/metabolism , Trans-Activators/metabolism , Transcription Factors/metabolism
12.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Article in English | MEDLINE | ID: mdl-34969857

ABSTRACT

Type I interferons (IFNs) are the first frontline of the host innate immune response against invading pathogens. Herein, we characterized an unknown protein encoded by phospholipase A2 inhibitor and LY6/PLAUR domain-containing (PINLYP) gene that interacted with TBK1 and induced type I IFN in a TBK1- and IRF3-dependent manner. Loss of PINLYP impaired the activation of IRF3 and production of IFN-ß induced by DNA virus, RNA virus, and various Toll-like receptor ligands in multiple cell types. Because PINLYP deficiency in mice engendered an early embryonic lethality in mice, we generated a conditional mouse in which PINLYP was depleted in dendritic cells. Mice lacking PINLYP in dendritic cells were defective in type I IFN induction and more susceptible to lethal virus infection. Thus, PINLYP is a positive regulator of type I IFN innate immunity and important for effective host defense against viral infection.


Subject(s)
Dendritic Cells/immunology , Enzyme Inhibitors/immunology , Immunity, Innate , Interferon-beta/immunology , Animals , Cell Line , DNA Virus Infections/genetics , DNA Virus Infections/immunology , DNA Viruses/genetics , DNA Viruses/immunology , Humans , Interferon-beta/genetics , Mice , Mice, Knockout , RNA Virus Infections/genetics , RNA Virus Infections/immunology , RNA Viruses/genetics , RNA Viruses/immunology
13.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Article in English | MEDLINE | ID: mdl-35217598

ABSTRACT

Seed vigor in crops is important in terms of improving grain quality and germplasm conservation; however, little is known about its regulatory mechanisms through the encoded proteome and gene network. Comparative analyses of transcriptome (RNA sequencing [RNA-seq]) and broadly targeted metabolic profiling of two subspecific rice cultivars with distinct seed vigor during accelerated aging revealed various biological pathways and metabolic processes as key influences explaining trait differences. RNA-seq coexpression regulatory network analyses identified several transcription factors, including bZIP23 and bZIP42, that act as nodes in the gene network. Importantly, transgenic seeds of overexpression of bZIP23 enhanced seed vigor, whereas its gene knockout reduced seed vigor, suggesting that the protein it encodes functions as a positive regulator. Similarly, overexpression and knockout of PER1A that encodes a key player in the detoxification pathway enhanced and decreased seed vigor, respectively. We further demonstrated a direct interaction of the PER1A promoter with bZIP23 in seeds, which activates the expression of PER1A, and the genetic evidence suggested that bZIP23 most likely functions in a common pathway with and acts upstream of PER1A to modulate seed vigor. In addition, the control of seed vigor by the bZIP23-PER1A module was connected with that of the abscisic acid signaling pathway. Collectively, we revealed the genetic architecture of variation in seed vigor and uncovered the bZIP23-PER1A-mediated detoxification pathway that enhances the trait in rice.


Subject(s)
Genome, Plant , Hybrid Vigor , Metabolome , Oryza/embryology , Peroxiredoxins/metabolism , Plant Proteins/metabolism , Seeds/physiology , Abscisic Acid/metabolism , Gene Expression Profiling , Gene Expression Regulation, Plant , Genes, Plant , Oryza/genetics , Oryza/metabolism , Seeds/metabolism , Signal Transduction
14.
J Neurosci ; 43(15): 2665-2681, 2023 04 12.
Article in English | MEDLINE | ID: mdl-36898835

ABSTRACT

The Slack channel (KCNT1, Slo2.2) is a sodium-activated and chloride-activated potassium channel that regulates heart rate and maintains the normal excitability of the nervous system. Despite intense interest in the sodium gating mechanism, a comprehensive investigation to identify the sodium-sensitive and chloride-sensitive sites has been missing. In the present study, we identified two potential sodium-binding sites in the C-terminal domain of the rat Slack channel by conducting electrophysical recordings and systematic mutagenesis of cytosolic acidic residues in the rat Slack channel C terminus. In particular, by taking advantage of the M335A mutant, which results in the opening of the Slack channel in the absence of cytosolic sodium, we found that among the 92 screened negatively charged amino acids, E373 mutants could completely remove sodium sensitivity of the Slack channel. In contrast, several other mutants showed dramatic decreases in sodium sensitivity but did not abolish it altogether. Furthermore, molecular dynamics (MD) simulations performed at the hundreds of nanoseconds timescale revealed one or two sodium ions at the E373 position or an acidic pocket composed of several negatively charged residues. Moreover, the MD simulations predicted possible chloride interaction sites. By screening predicted positively charged residues, we identified R379 as a chloride interaction site. Thus, we conclude that the E373 site and the D863/E865 pocket are two potential sodium-sensitive sites, while R379 is a chloride interaction site in the Slack channel.SIGNIFICANCE STATEMENT The research presented here identified two distinct sodium and one chloride interaction sites located in the intracellular C-terminal domain of the Slack (Slo2.2, KCNT1) channel. Identification of the sites responsible for the sodium and chloride activation of the Slack channel sets its gating property apart from other potassium channels in the BK channel family. This finding sets the stage for future functional and pharmacological studies of this channel.


Subject(s)
Potassium Channels, Sodium-Activated , Animals , Rats , Chlorides/metabolism , Potassium Channels, Sodium-Activated/metabolism , Sodium/metabolism
15.
J Cell Physiol ; 239(2): e31129, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38192063

ABSTRACT

Myelodysplastic syndromes (MDS) are a group of heterogeneous myeloid clonal disorders characterized by ineffective hematopoiesis. Accumulating evidence has shown that macrophages (MΦs) are important components in the regulation of tumor progression and hematopoietic stem cells (HSCs). However, the roles of bone marrow (BM) MΦs in regulating normal and malignant hematopoiesis in different clinical stages of MDS are largely unknown. Age-paired patients with lower-risk MDS (N = 15), higher-risk MDS (N = 15), de novo acute myeloid leukemia (AML) (N = 15), and healthy donors (HDs) (N = 15) were enrolled. Flow cytometry analysis showed increased pro-inflammatory monocyte subsets and a decreased classically activated (M1) MΦs/alternatively activated (M2) MΦs ratio in the BM of patients with higher-risk MDS compared to lower-risk MDS. BM MФs from patients with higher-risk MDS and AML showed impaired phagocytosis activity but increased migration compared with lower-risk MDS group. AML BM MΦs showed markedly higher S100A8/A9 levels than lower-risk MDS BM MΦs. More importantly, coculture experiments suggested that the HSC supporting abilities of BM MΦs from patients with higher-risk MDS decreased, whereas the malignant cell supporting abilities increased compared with lower-risk MDS. Gene Ontology enrichment comparing BM MΦs from lower-risk MDS and higher-risk MDS for genes was involved in hematopoiesis- and immunity-related pathways. Our results suggest that BM MΦs are involved in ineffective hematopoiesis in patients with MDS, which indicates that repairing aberrant BM MΦs may represent a promising therapeutic approach for patients with MDS.


Subject(s)
Infections , Macrophages , Myelodysplastic Syndromes , Humans , Bone Marrow/pathology , Hematopoiesis , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , Macrophages/pathology , Myelodysplastic Syndromes/genetics , Adult , Middle Aged , Aged , Aged, 80 and over , Infections/pathology
16.
J Am Chem Soc ; 146(4): 2411-2418, 2024 01 31.
Article in English | MEDLINE | ID: mdl-38234111

ABSTRACT

Nanographene C222, which consists of a planar graphenic plane containing 222 carbon atoms, holds the record as the largest planar nanographene synthesized to date. However, its complete insolubility makes the processing of C222 difficult. Here we addressed this issue by introducing peripheral substituents perpendicular to the graphene plane, effectively disrupting the interlayer stacking and endowing C222 with good solubility. We also found that the electron-withdrawing substituents played a crucial role in the cyclodehydrogenation process, converting the dendritic polyphenylene precursor to C222. After disrupting the interlayer stacking, the introduction of only a few peripheral carboxylic groups allowed C222 to dissolve in phosphate buffer saline, reaching a concentration of up to 0.5 mg/mL. Taking advantage of the good photosensitizing and photothermal properties of the inner C222 core, the resulting water-soluble C222 emerged as a single-component agent for both photothermal and photodynamic tumor therapy, exhibiting an impressive tumor inhibition rate of 96%.


Subject(s)
Nanoparticles , Neoplasms , Photochemotherapy , Humans , Photosensitizing Agents/pharmacology , Photosensitizing Agents/therapeutic use , Photothermal Therapy , Photochemotherapy/methods , Neoplasms/drug therapy
17.
PLoS Med ; 21(5): e1004389, 2024 May.
Article in English | MEDLINE | ID: mdl-38728364

ABSTRACT

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Camptothecin , Cetuximab , Colorectal Neoplasms , Fluorouracil , Leucovorin , Liver Neoplasms , Organoplatinum Compounds , Proto-Oncogene Proteins B-raf , Humans , Cetuximab/administration & dosage , Cetuximab/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Male , Middle Aged , Liver Neoplasms/secondary , Liver Neoplasms/drug therapy , Female , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Leucovorin/therapeutic use , Leucovorin/administration & dosage , Fluorouracil/therapeutic use , Fluorouracil/administration & dosage , Organoplatinum Compounds/therapeutic use , Organoplatinum Compounds/administration & dosage , Proto-Oncogene Proteins B-raf/genetics , Aged , Adult , Camptothecin/analogs & derivatives , Camptothecin/therapeutic use , Camptothecin/administration & dosage , Treatment Outcome , ras Proteins/genetics
18.
Anal Chem ; 96(5): 1890-1897, 2024 02 06.
Article in English | MEDLINE | ID: mdl-38262068

ABSTRACT

Despite substantial efforts to detect host cell proteins (HCPs) in antibody drugs, information regarding HCPs in gene therapy products remains limited and has not been widely integrated into the host cell engineering or purification processes. Most methods that have successfully detected HCPs in antibody drugs are not applicable to gene therapy products, except for the ProteoMiner enrichment method. Here, we demonstrate that ProteoMiner beads effectively enrich HCPs in adeno-associated virus (AAV) products and simultaneously remove the detergent Pluronic F-68 without a loss of low-abundance HCPs. Following optimization of this technique, there was up to a 34-fold increase in the enrichment of HCPs compared to direct digestion. Moreover, the detection limit was significantly lowered with the ability to detect HCPs at levels as low as 0.1 ng/mL after ProteoMiner treatment. This approach holds promise in AAV HCP analysis and may be adaptable to other gene therapy products. The findings from this study provide valuable insights into HCPs in AAV products and may facilitate process development and host cell line optimization. The high sensitivity of this approach also facilitates detection of critical low-abundance HCPs, thereby contributing to risk assessment of their impact on the safety and quality of the AAV-based gene therapy products.


Subject(s)
Antibodies, Monoclonal , Dependovirus , Cricetinae , Animals , Antibodies, Monoclonal/metabolism , Dependovirus/genetics , Dependovirus/metabolism , Cricetulus , CHO Cells , Technology
19.
Eur J Immunol ; 53(10): e2149510, 2023 10.
Article in English | MEDLINE | ID: mdl-37572379

ABSTRACT

Mesenchymal stromal cells (MSCs) have long been considered a potential tool for treatment of allergic inflammatory diseases, owing to their immunomodulatory characteristics. In recent decades, the medical utility of MSCs has been evaluated both in vitro and in vivo, providing a foundation for therapeutic applications. However, the existing limitations of MSC therapy indicate the necessity for novel therapies. Notably, small extracellular vesicles (sEV) derived from MSCs have emerged rapidly as candidates instead of their parental cells. The acquisition of abundant and scalable MSC-sEV is an obstacle for clinical applications. The potential application of MSC-sEV in allergic diseases has attracted increasing attention from researchers. By carrying biological microRNAs or active proteins, MSC-sEV can modulate the function of various innate and adaptive immune cells. In this review, we summarise the recent advances in the immunomodulatory properties of MSCs in allergic diseases, the cellular sources of MSC-sEV, and the methods for obtaining high-quality human MSC-sEV. In addition, we discuss the immunoregulatory capacity of MSCs and MSC-sEV for the treatment of asthma, atopic dermatitis, and allergic rhinitis, with a special emphasis on their immunoregulatory effects and the underlying mechanisms of immune cell modulation.


Subject(s)
Asthma , Extracellular Vesicles , Mesenchymal Stem Cells , MicroRNAs , Humans , Extracellular Vesicles/metabolism , MicroRNAs/metabolism , Asthma/therapy , Asthma/metabolism , Immunomodulation
20.
BMC Med ; 22(1): 176, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38664766

ABSTRACT

BACKGROUND: There is an urgent unmet need for effective initial treatment for acute graft-versus-host disease (aGVHD) adding to the standard first-line therapy with corticosteroids after allogeneic haematopoietic stem cell transplantation (allo-HSCT). METHODS: We performed a multicentre, open-label, randomized, phase 3 study. Eligible patients (aged 15 years or older, had received allo-HSCT for a haematological malignancy, developed aGVHD, and received no previous therapies for aGVHD) were randomly assigned (1:1) to receive either 5 mg/m2 MTX on Days 1, 3, or 8 and then combined with corticosteroids or corticosteroids alone weekly. RESULTS: The primary endpoint was the overall response rate (ORR) on Day 10. A total of 157 patients were randomly assigned to receive either MTX plus corticosteroids (n = 78; MTX group) or corticosteroids alone (n = 79; control group). The Day 10 ORR was 97% for the MTX group and 81% for the control group (p = .005). Among patients with mild aGVHD, the Day 10 ORR was 100% for the MTX group and 86% for the control group (p = .001). The 1-year estimated failure-free survival was 69% for the MTX group and 41% for the control group (p = .002). There were no differences in treatment-related adverse events between the two groups. CONCLUSIONS: In conclusion, mini-dose MTX combined with corticosteroids can significantly improve the ORR in patients with aGVHD and is well tolerated, although it did not achieve the prespecified 20% improvement with the addition of MTX. TRIAL REGISTRATION: The trial was registered with clinicaltrials.gov (NCT04960644).


Subject(s)
Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Methotrexate , Methylprednisolone , Humans , Graft vs Host Disease/drug therapy , Female , Male , Methotrexate/administration & dosage , Methotrexate/therapeutic use , Middle Aged , Adult , Methylprednisolone/therapeutic use , Methylprednisolone/administration & dosage , Hematopoietic Stem Cell Transplantation/adverse effects , Young Adult , Treatment Outcome , Drug Therapy, Combination , Aged , Adolescent , Acute Disease
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