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1.
Cell ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38971151

ABSTRACT

Homologous recombination deficiency (HRD) is prevalent in cancer, sensitizing tumor cells to poly (ADP-ribose) polymerase (PARP) inhibition. However, the impact of HRD and related therapies on the tumor microenvironment (TME) remains elusive. Our study generates single-cell gene expression and T cell receptor profiles, along with validatory multimodal datasets from >100 high-grade serous ovarian cancer (HGSOC) samples, primarily from a phase II clinical trial (NCT04507841). Neoadjuvant monotherapy with the PARP inhibitor (PARPi) niraparib achieves impressive 62.5% and 73.6% response rates per RECIST v.1.1 and GCIG CA125, respectively. We identify effector regulatory T cells (eTregs) as key responders to HRD and neoadjuvant therapies, co-occurring with other tumor-reactive T cells, particularly terminally exhausted CD8+ T cells (Tex). TME-wide interferon signaling correlates with cancer cells upregulating MHC class II and co-inhibitory ligands, potentially driving Treg and Tex fates. Depleting eTregs in HRD mouse models, with or without PARP inhibition, significantly suppresses tumor growth without observable toxicities, underscoring the potential of eTreg-focused therapeutics for HGSOC and other HRD-related tumors.

2.
Nat Immunol ; 22(9): 1175-1185, 2021 09.
Article in English | MEDLINE | ID: mdl-34429546

ABSTRACT

Systematic characterizations of adipose regulatory T (Treg) cell subsets and their phenotypes remain uncommon. Using single-cell ATAC-sequencing and paired single-cell RNA and T cell receptor (TCR) sequencing to map mouse adipose Treg cells, we identified CD73hiST2lo and CD73loST2hi subsets with distinct clonal expansion patterns. Analysis of TCR-sharing data implied a state transition between CD73hiST2lo and CD73loST2hi subsets. Mechanistically, we revealed that insulin signaling occurs through a HIF-1α-Med23-PPAR-γ axis to drive the transition of CD73hiST2lo into a CD73loST2hi adipose Treg cell subset. Treg cells deficient in insulin receptor, HIF-1α or Med23 have decreased PPAR-γ expression that in turn promotes accumulation of CD73hiST2lo adipose Treg cells and physiological adenosine production to activate beige fat biogenesis. We therefore unveiled a developmental trajectory of adipose Treg cells and its dependence on insulin signaling. Our findings have implications for understanding the dynamics of adipose Treg cell subsets in aged and obese contexts.


Subject(s)
Adipose Tissue/immunology , Insulin Resistance/immunology , Insulin/metabolism , Receptor, Insulin/metabolism , T-Lymphocytes, Regulatory/immunology , 5'-Nucleotidase/genetics , 5'-Nucleotidase/metabolism , Adipose Tissue/cytology , Aging/immunology , Animals , Cells, Cultured , High-Throughput Nucleotide Sequencing , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Interleukin-1 Receptor-Like 1 Protein/genetics , Interleukin-1 Receptor-Like 1 Protein/metabolism , Male , Mediator Complex/metabolism , Mice , Mice, Inbred C57BL , Obesity/genetics , Obesity/immunology , PPAR gamma/metabolism , Receptors, Antigen, T-Cell/genetics , Signal Transduction/genetics , Signal Transduction/immunology , T-Lymphocytes, Regulatory/cytology
3.
Immunity ; 54(10): 2305-2320.e11, 2021 10 12.
Article in English | MEDLINE | ID: mdl-34508661

ABSTRACT

Langerhans cells (LCs) play a pivotal role in skin homeostasis, and the heterogeneity of LCs has long been considered. In this study, we have identified two steady-state (LC1 and LC2) and two activated LC subsets in the epidermis of human skin and in LCs derived from CD34+ hemopoietic stem cells (HSC-LCs) by utilizing single-cell RNA sequencing and mass cytometry. Analysis of HSC-LCs at multiple time-points during differentiation revealed that EGR1 and Notch signaling were among the top pathways regulating the bifurcation of LC1 and LC2. LC1 were characterized as classical LCs, mainly related to innate immunity and antigen processing. LC2 were similar to monocytes or myeloid dendritic cells, involving in immune responses and leukocyte activation. LC1 remained stable under inflammatory microenvironment, whereas LC2 were prone to being activated and demonstrated elevated expression of immuno-suppressive molecules. We revealed distinct human LC subsets that require different developmental regulation and orchestrate reciprocal functions.


Subject(s)
Cell Differentiation/immunology , Langerhans Cells/cytology , Langerhans Cells/immunology , Skin/cytology , Skin/immunology , Antigen Presentation/immunology , Hematopoietic Stem Cells/immunology , Humans , Immunity, Innate/immunology
4.
Immunity ; 51(3): 443-450.e4, 2019 09 17.
Article in English | MEDLINE | ID: mdl-31422870

ABSTRACT

The presence of gallstones (cholelithiasis) is a highly prevalent and severe disease and one of the leading causes of hospital admissions worldwide. Due to its substantial health impact, we investigated the biological mechanisms that lead to the formation and growth of gallstones. We show that gallstone assembly essentially requires neutrophil extracellular traps (NETs). We found consistent evidence for the presence of NETs in human and murine gallstones and describe an immune-mediated process requiring activation of the innate immune system for the formation and growth of gallstones. Targeting NET formation via inhibition of peptidyl arginine deiminase type 4 or abrogation of reactive oxygen species (ROS) production, as well as damping of neutrophils by metoprolol, effectively inhibit gallstone formation in vivo. Our results show that after the physicochemical process of crystal formation, NETs foster their assembly into larger aggregates and finally gallstones. These insights provide a feasible therapeutic concept to prevent cholelithiasis in patients at risk.


Subject(s)
Extracellular Traps/immunology , Gallstones/immunology , Neutrophils/immunology , Animals , Female , Humans , Immunity, Innate/immunology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Reactive Oxygen Species/immunology
5.
Immunol Rev ; 321(1): 280-299, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37850797

ABSTRACT

Neutrophils are important in the context of innate immunity and actively contribute to the progression of diverse autoimmune disorders. Distinct death mechanisms of neutrophils may exhibit specific and pivotal roles in autoimmune diseases and disease pathogenesis through the orchestration of immune homeostasis, the facilitation of autoantibody production, the induction of tissue and organ damage, and the incitement of pathological alterations. In recent years, more studies have provided in-depth examination of various neutrophil death modes, revealing nuances that challenge conventional understanding and underscoring their potential clinical utility in diagnosis and treatment. This review explores the multifaceted processes and characteristics of neutrophil death, with a focus on tailored investigations within various autoimmune diseases. It also highlights the potential interplay between neutrophil death and the landscape of autoimmune disorders. The review encapsulates the pertinent pathways implicated in various neutrophil death mechanisms across diverse autoimmune diseases while also charts possible avenues for future research.


Subject(s)
Autoimmune Diseases , Neutrophils , Humans , Immunity, Innate
6.
Nat Methods ; 21(4): 712-722, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38491270

ABSTRACT

Spatial clustering, which shares an analogy with single-cell clustering, has expanded the scope of tissue physiology studies from cell-centroid to structure-centroid with spatially resolved transcriptomics (SRT) data. Computational methods have undergone remarkable development in recent years, but a comprehensive benchmark study is still lacking. Here we present a benchmark study of 13 computational methods on 34 SRT data (7 datasets). The performance was evaluated on the basis of accuracy, spatial continuity, marker genes detection, scalability, and robustness. We found existing methods were complementary in terms of their performance and functionality, and we provide guidance for selecting appropriate methods for given scenarios. On testing additional 22 challenging datasets, we identified challenges in identifying noncontinuous spatial domains and limitations of existing methods, highlighting their inadequacies in handling recent large-scale tasks. Furthermore, with 145 simulated data, we examined the robustness of these methods against four different factors, and assessed the impact of pre- and postprocessing approaches. Our study offers a comprehensive evaluation of existing spatial clustering methods with SRT data, paving the way for future advancements in this rapidly evolving field.


Subject(s)
Benchmarking , Gene Expression Profiling , Cluster Analysis , Spatial Analysis , Transcriptome
7.
Nat Methods ; 20(3): 387-399, 2023 03.
Article in English | MEDLINE | ID: mdl-36797409

ABSTRACT

Spatial omics technologies generate wealthy but highly complex datasets. Here we present Spatial Omics DataBase (SODB), a web-based platform providing both rich data resources and a suite of interactive data analytical modules. SODB currently maintains >2,400 experiments from >25 spatial omics technologies, which are freely accessible as a unified data format compatible with various computational packages. SODB also provides multiple interactive data analytical modules, especially a unique module, Spatial Omics View (SOView). We conduct comprehensive statistical analyses and illustrate the utility of both basic and advanced analytical modules using multiple spatial omics datasets. We demonstrate SOView utility with brain spatial transcriptomics data and recover known anatomical structures. We further delineate functional tissue domains with associated marker genes that were obscured when analyzed using previous methods. We finally show how SODB may efficiently facilitate computational method development. The SODB website is https://gene.ai.tencent.com/SpatialOmics/ . The command-line package is available at https://pysodb.readthedocs.io/en/latest/ .


Subject(s)
Gene Expression Profiling , Software , Databases, Factual , Gene Expression Profiling/methods
8.
J Immunol ; 213(2): 170-186, 2024 07 15.
Article in English | MEDLINE | ID: mdl-38819229

ABSTRACT

Myeloid-derived suppressor cells (MDSCs), the negative immune regulators, have been demonstrated to be involved in immune responses to a variety of pathological conditions, such as tumors, chronic inflammation, and infectious diseases. However, the roles and mechanisms underlying the expansion of MDSCs in malaria remain unclear. In this study, the phenotypic and functional characteristics of splenic MDSCs during Plasmodium yoelii NSM infection are described. Furthermore, we provide compelling evidence that the sera from P. yoelii-infected C57BL/6 mice containing excess IL-6 and granulocyte-macrophage colony-stimulating factor promote the accumulation of MDSCs by inducing Bcl2 expression. Serum-induced MDSCs exert more potent suppressive effects on T cell responses than control MDSCs within both in vivo P. yoelii infection and in vitro serum-treated bone marrow cells experiments. Serum treatment increases the MDSC inhibitory effect, which is dependent on Arg1 expression. Moreover, mechanistic studies reveal that the serum effects are mediated by JAK/STAT3 signaling. By inhibiting STAT3 phosphorylation with the JAK inhibitor JSI-124, effects of serum on MDSCs are almost eliminated. In vivo depletion of MDSCs with anti-Gr-1 or 5-fluorouracil significantly reduces the parasitemia and promotes Th1 immune response in P. yoelii-infected C57BL/6 mice by upregulating IFN-γ expression. In summary, this study indicates that P. yoelii infection facilitates the accumulation and function of MDSCs by upregulating the expression of Bcl2 and Arg1 via JAK/STAT3 signaling pathway in vivo and in vitro. Manipulating the JAK/STAT3 signaling pathway or depleting MDSCs could be promising therapeutic interventions to treat malaria.


Subject(s)
Janus Kinases , Malaria , Mice, Inbred C57BL , Myeloid-Derived Suppressor Cells , Plasmodium yoelii , STAT3 Transcription Factor , Signal Transduction , Animals , Plasmodium yoelii/immunology , Malaria/immunology , Myeloid-Derived Suppressor Cells/immunology , Mice , STAT3 Transcription Factor/metabolism , Signal Transduction/immunology , Janus Kinases/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Arginase/metabolism , Interleukin-6/metabolism , Interleukin-6/immunology , Female
9.
Nature ; 588(7838): 419-423, 2020 12.
Article in English | MEDLINE | ID: mdl-33328665

ABSTRACT

A quantum anomalous Hall (QAH) state is a two-dimensional topological insulating state that has a quantized Hall resistance of h/(Ce2) and vanishing longitudinal resistance under zero magnetic field (where h is the Planck constant, e is the elementary charge, and the Chern number C is an integer)1,2. The QAH effect has been realized in magnetic topological insulators3-9 and magic-angle twisted bilayer graphene10,11. However, the QAH effect at zero magnetic field has so far been realized only for C = 1. Here we realize a well quantized QAH effect with tunable Chern number (up to C = 5) in multilayer structures consisting of alternating magnetic and undoped topological insulator layers, fabricated using molecular beam epitaxy. The Chern number of these QAH insulators is determined by the number of undoped topological insulator layers in the multilayer structure. Moreover, we demonstrate that the Chern number of a given multilayer structure can be tuned by varying either the magnetic doping concentration in the magnetic topological insulator layers or the thickness of the interior magnetic topological insulator layer. We develop a theoretical model to explain our experimental observations and establish phase diagrams for QAH insulators with high, tunable Chern number. The realization of such insulators facilitates the application of dissipationless chiral edge currents in energy-efficient electronic devices, and opens up opportunities for developing multi-channel quantum computing and higher-capacity chiral circuit interconnects.

10.
Proc Natl Acad Sci U S A ; 120(10): e2219388120, 2023 Mar 07.
Article in English | MEDLINE | ID: mdl-36848559

ABSTRACT

The soluble fraction of atmospheric transition metals is particularly associated with health effects such as reactive oxygen species compared to total metals. However, direct measurements of the soluble fraction are restricted to sampling and detection units in sequence burdened with a compromise between time resolution and system bulkiness. Here, we propose the concept of aerosol-into-liquid capture and detection, which allowed one-step particle capture and detection via the Janus-membrane electrode at the gas-liquid interface, enabling active enrichment and enhanced mass transport of metal ions. The integrated aerodynamic/electrochemical system was capable of capturing airborne particles with a cutoff size down to 50 nm and detecting Pb(II) with a limit of detection of 95.7 ng. The proposed concept can pave the way for cost-effective and miniaturized systems, for the capture and detection of airborne soluble metals in air quality monitoring, especially for abrupt air pollution events with high airborne metal concentrations (e.g., wildfires and fireworks).

11.
J Neurosci ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38926088

ABSTRACT

Current anesthetic theory is mostly based on neurons and/or neuronal circuits. A role for astrocytes also has been shown in promoting recovery from volatile anesthesia, while the exact modulatory mechanism and/or the molecular target in astrocytes is still unknown. In this study, by animal models in male mice and electrophysiological recordings in vivo and in vitro, we found that activating astrocytes of paraventricular thalamus (PVT) and/or knocking down PVT astrocytic Kir4.1 promoted the consciousness recovery from sevoflurane anesthesia. Single-cell RNA sequencing of PVT reveals two distinct cellular subtypes of glutamatergic neurons: PVT GRM and PVT ChAT neurons. Patch-clamp recording results proved astrocytic Kir4.1-mediated modulation of sevoflurane on PVT mainly worked on PVT ChAT neurons, which projected mainly to the mPFC. In summary, our findings support the novel conception that there is a specific PVT-prefrontal cortex projection involved in consciousness recovery from sevoflurane anesthesia, which mediated by the inhibition of sevoflurane on PVT astrocytic Kir4.1 conductance.Significance Statement How volatile anesthetics work is not fully understood. Here, we demonstrate that the commonly used volatile anesthetic sevoflurane can inhibit astrocytic Kir4.1 conductance in PVT, which enhances neuronal firing of PVT neurons. Additionally, by single-cell sequencing, cholinergic neurons in the PVT (PVT ChAT ) are the neuronal substrates for astrocytic modulation in volatile anesthesia, which directly project to prefrontal cortex. Behaviorally, the modulation of astrocytes on PVT ChAT promotes electroencephalogram (EEG) transition of prefrontal cortex; and then accelerates emergence from sevoflurane anesthesia. In summary, this study is the first to identify that astrocytic Kir4.1 in wakeful nuclei is involved in consciousness recovery from volatile anesthetics, as well as the subcellular mechanism.

12.
J Biol Chem ; 300(6): 107343, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38705395

ABSTRACT

Rieske nonheme iron aromatic ring-hydroxylating oxygenases (RHOs) play pivotal roles in determining the substrate preferences of polycyclic aromatic hydrocarbon (PAH) degraders. However, their potential to degrade high molecular weight PAHs (HMW-PAHs) has been relatively unexplored. NarA2B2 is an RHO derived from a thermophilic Hydrogenibacillus sp. strain N12. In this study, we have identified four "hotspot" residues (V236, Y300, W316, and L375) that may hinder the catalytic capacity of NarA2B2 when it comes to HMW-PAHs. By employing structure-guided rational enzyme engineering, we successfully modified NarA2B2, resulting in NarA2B2 variants capable of catalyzing the degradation of six different types of HMW-PAHs, including pyrene, fluoranthene, chrysene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene. Three representative variants, NarA2B2W316I, NarA2B2Y300F-W316I, and NarA2B2V236A-W316I-L375F, not only maintain their abilities to degrade low-molecular-weight PAHs (LMW-PAHs) but also exhibited 2 to 4 times higher degradation efficiency for HMW-PAHs in comparison to another isozyme, NarAaAb. Computational analysis of the NarA2B2 variants predicts that these modifications alter the size and hydrophobicity of the active site pocket making it more suitable for HMW-PAHs. These findings provide a comprehensive understanding of the relationship between three-dimensional structure and functionality, thereby opening up possibilities for designing improved RHOs that can be more effectively used in the bioremediation of PAHs.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Polycyclic Aromatic Hydrocarbons/metabolism , Polycyclic Aromatic Hydrocarbons/chemistry , Molecular Weight , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Substrate Specificity , Biodegradation, Environmental , Oxygenases/metabolism , Oxygenases/chemistry , Oxygenases/genetics , Hydroxylation
13.
J Biol Chem ; 300(6): 107379, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38762184

ABSTRACT

Bacterial RecJ exhibits 5'→3' exonuclease activity that is specific to ssDNA; however, archaeal RecJs show 5' or 3' exonuclease activity. The hyperthermophilic archaea Methanocaldococcus jannaschii encodes the 5'-exonuclease MjRecJ1 and the 3'-exonuclease MjRecJ2. In addition to nuclease activity, archaeal RecJ interacts with GINS, a structural subcomplex of the replicative DNA helicase complex. However, MjRecJ1 and MjRecJ2 do not interact with MjGINS. Here, we report the structural basis for the inability of the MjRecJ2 homologous dimer to interact with MjGINS and its efficient 3' hydrolysis polarity for short dinucleotides. Based on the crystal structure of MjRecJ2, we propose that the interaction surface of the MjRecJ2 dimer overlaps the potential interaction surface for MjGINS and blocks the formation of the MjRecJ2-GINS complex. Exposing the interaction surface of the MjRecJ2 dimer restores its interaction with MjGINS. The cocrystal structures of MjRecJ2 with substrate dideoxynucleotides or product dCMP/CMP show that MjRecJ2 has a short substrate binding patch, which is perpendicular to the longer patch of bacterial RecJ. Our results provide new insights into the function and diversification of archaeal RecJ/Cdc45 proteins.


Subject(s)
Archaeal Proteins , Archaeal Proteins/chemistry , Archaeal Proteins/metabolism , Archaeal Proteins/genetics , Crystallography, X-Ray , Methanocaldococcus/enzymology , Methanocaldococcus/metabolism , Protein Binding , Protein Multimerization , DNA Helicases/metabolism , DNA Helicases/chemistry , DNA Helicases/genetics , Models, Molecular , Exodeoxyribonucleases/metabolism , Exodeoxyribonucleases/chemistry , Exodeoxyribonucleases/genetics
14.
Circulation ; 149(21): 1650-1666, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38344825

ABSTRACT

BACKGROUND: Much of our knowledge of organ rejection after transplantation is derived from rodent models. METHODS: We used single-nucleus RNA sequencing to investigate the inflammatory myocardial microenvironment in human pediatric cardiac allografts at different stages after transplantation. We distinguished donor- from recipient-derived cells using naturally occurring genetic variants embedded in single-nucleus RNA sequencing data. RESULTS: Donor-derived tissue resident macrophages, which accompany the allograft into the recipient, are lost over time after transplantation. In contrast, monocyte-derived macrophages from the recipient populate the heart within days after transplantation and form 2 macrophage populations: recipient MP1 and recipient MP2. Recipient MP2s have cell signatures similar to donor-derived resident macrophages; however, they lack signatures of pro-reparative phagocytic activity typical of donor-derived resident macrophages and instead express profibrotic genes. In contrast, recipient MP1s express genes consistent with hallmarks of cellular rejection. Our data suggest that recipient MP1s activate a subset of natural killer cells, turning them into a cytotoxic cell population through feed-forward signaling between recipient MP1s and natural killer cells. CONCLUSIONS: Our findings reveal an imbalance of donor-derived and recipient-derived macrophages in the pediatric cardiac allograft that contributes to allograft failure.


Subject(s)
Allografts , Graft Rejection , Heart Transplantation , Macrophages , Humans , Heart Transplantation/adverse effects , Macrophages/metabolism , Graft Rejection/immunology , Graft Rejection/genetics , Male , Female , Child , Child, Preschool , Myocardium/pathology , Graft Survival , Infant , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Adolescent
15.
Biostatistics ; 2024 Mar 17.
Article in English | MEDLINE | ID: mdl-38494649

ABSTRACT

Genetic association studies for brain connectivity phenotypes have gained prominence due to advances in noninvasive imaging techniques and quantitative genetics. Brain connectivity traits, characterized by network configurations and unique biological structures, present distinct challenges compared to other quantitative phenotypes. Furthermore, the presence of sample relatedness in the most imaging genetics studies limits the feasibility of adopting existing network-response modeling. In this article, we fill this gap by proposing a Bayesian network-response mixed-effect model that considers a network-variate phenotype and incorporates population structures including pedigrees and unknown sample relatedness. To accommodate the inherent topological architecture associated with the genetic contributions to the phenotype, we model the effect components via a set of effect network configurations and impose an inter-network sparsity and intra-network shrinkage to dissect the phenotypic network configurations affected by the risk genetic variant. A Markov chain Monte Carlo (MCMC) algorithm is further developed to facilitate uncertainty quantification. We evaluate the performance of our model through extensive simulations. By further applying the method to study, the genetic bases for brain structural connectivity using data from the Human Connectome Project with excessive family structures, we obtain plausible and interpretable results. Beyond brain connectivity genetic studies, our proposed model also provides a general linear mixed-effect regression framework for network-variate outcomes.

16.
Brief Bioinform ; 24(2)2023 03 19.
Article in English | MEDLINE | ID: mdl-36682018

ABSTRACT

The determination of transcriptome profiles that mediate immune therapy in cancer remains a major clinical and biological challenge. Despite responses induced by immune-check points inhibitors (ICIs) in diverse tumor types and all the big breakthroughs in cancer immunotherapy, most patients with solid tumors do not respond to ICI therapies. It still remains a big challenge to predict the ICI treatment response. Here, we propose a framework with multiple prior knowledge networks guided for immune checkpoints inhibitors prediction-DeepOmix-ICI (or ICInet for short). ICInet can predict the immune therapy response by leveraging geometric deep learning and prior biological knowledge graphs of gene-gene interactions. Here, we demonstrate more than 600 ICI-treated patients with ICI response data and gene expression profile to apply on ICInet. ICInet was used for ICI therapy responses prediciton across different cancer types-melanoma, gastric cancer and bladder cancer, which includes 7 cohorts from different data sources. ICInet is able to robustly generalize into multiple cancer types. Moreover, the performance of ICInet in those cancer types can outperform other ICI biomarkers in the clinic. Our model [area under the curve (AUC = 0.85)] generally outperformed other measures, including tumor mutational burden (AUC = 0.62) and programmed cell death ligand-1 score (AUC = 0.74). Therefore, our study presents a prior-knowledge guided deep learning method to effectively select immunotherapy-response-associated biomarkers, thereby improving the prediction of immunotherapy response for precision oncology.


Subject(s)
Melanoma , Urinary Bladder Neoplasms , Humans , Pattern Recognition, Automated , Precision Medicine , Melanoma/pathology , Immunotherapy/methods , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism
17.
Nat Mater ; 23(7): 993-1001, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38594486

ABSTRACT

DNA origami is capable of spatially organizing molecules into sophisticated geometric patterns with nanometric precision. Here we describe a reconfigurable, two-dimensional DNA origami with geometrically patterned CD95 ligands that regulates immune cell signalling to alleviate rheumatoid arthritis. In response to pH changes, the device reversibly transforms from a closed to an open configuration, displaying a hexagonal pattern of CD95 ligands with ~10 nm intermolecular spacing, precisely mirroring the spatial arrangement of CD95 receptor clusters on the surface of immune cells. In a collagen-induced arthritis mouse model, DNA origami elicits robust and selective activation of CD95 death-inducing signalling in activated immune cells located in inflamed synovial tissues. Such localized immune tolerance ameliorates joint damage with no noticeable side effects. This device allows for the precise spatial control of cellular signalling, expanding our understanding of ligand-receptor interactions and is a promising platform for the development of pharmacological interventions targeting these interactions.


Subject(s)
Arthritis, Rheumatoid , DNA , Immune Tolerance , Signal Transduction , fas Receptor , Arthritis, Rheumatoid/immunology , Arthritis, Rheumatoid/metabolism , Arthritis, Rheumatoid/pathology , Animals , DNA/chemistry , DNA/immunology , Mice , fas Receptor/metabolism , fas Receptor/immunology , Fas Ligand Protein/metabolism , Fas Ligand Protein/immunology , Humans
18.
Nat Mater ; 23(1): 58-64, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37857889

ABSTRACT

A quantum anomalous Hall (QAH) insulator is a topological phase in which the interior is insulating but electrical current flows along the edges of the sample in either a clockwise or counterclockwise direction, as dictated by the spontaneous magnetization orientation. Such a chiral edge current eliminates any backscattering, giving rise to quantized Hall resistance and zero longitudinal resistance. Here we fabricate mesoscopic QAH sandwich Hall bar devices and succeed in switching the edge current chirality through thermally assisted spin-orbit torque (SOT). The well-quantized QAH states before and after SOT switching with opposite edge current chiralities are demonstrated through four- and three-terminal measurements. We show that the SOT responsible for magnetization switching can be generated by both surface and bulk carriers. Our results further our understanding of the interplay between magnetism and topological states and usher in an easy and instantaneous method to manipulate the QAH state.

19.
Plant Cell ; 34(1): 477-494, 2022 01 20.
Article in English | MEDLINE | ID: mdl-34850207

ABSTRACT

Stomatal movement is critical for plant responses to environmental changes and is regulated by the important signaling molecule phosphatidylinositol 3-phosphate (PI3P). However, the molecular mechanism underlying this process is not well understood. In this study, we show that PI3P binds to stomatal closure-related actin-binding protein1 (SCAB1), a plant-specific F-actin-binding and -bundling protein, and inhibits the oligomerization of SCAB1 to regulate its activity on F-actin in guard cells during stomatal closure in Arabidopsis thaliana. SCAB1 binds specifically to PI3P, but not to other phosphoinositides. Treatment with wortmannin, an inhibitor of phosphoinositide kinase that generates PI3P, leads to an increase of the intermolecular interaction and oligomerization of SCAB1, stabilization of F-actin, and retardation of F-actin reorganization during abscisic acid (ABA)-induced stomatal closure. When the binding activity of SCAB1 to PI3P is abolished, the mutated proteins do not rescue the stability and realignment of F-actin regulated by SCAB1 and the stomatal closure in the scab1 mutant. The expression of PI3P biosynthesis genes is consistently induced when the plants are exposed to drought and ABA treatments. Furthermore, the binding of PI3P to SCAB1 is also required for vacuolar remodeling during stomatal closure. Our results illustrate a PI3P-regulated pathway during ABA-induced stomatal closure, which involves the mediation of SCAB1 activity in F-actin reorganization.


Subject(s)
Actins/chemistry , Arabidopsis Proteins/genetics , Arabidopsis/physiology , Gene Expression Regulation, Plant , Microfilament Proteins/genetics , Phosphatidylinositol Phosphates/metabolism , Plant Stomata/physiology , Arabidopsis/genetics , Arabidopsis Proteins/metabolism , Microfilament Proteins/metabolism
20.
EMBO Rep ; 24(8): e56335, 2023 08 03.
Article in English | MEDLINE | ID: mdl-37341560

ABSTRACT

While there is growing evidence that many epigenetically silenced genes in cancer are tumour suppressor candidates, their significance in cancer biology remains unclear. Here, we identify human Neuralized (NEURL), which acts as a novel tumour suppressor targeting oncogenic Wnt/ß-catenin signalling in human cancers. The expression of NEURL is epigenetically regulated and markedly suppressed in human colorectal cancer. We, therefore, considered NEURL to be a bona fide tumour suppressor in colorectal cancer and demonstrate that this tumour suppressive function depends on NEURL-mediated oncogenic ß-catenin degradation. We find that NEURL acts as an E3 ubiquitin ligase, interacting directly with oncogenic ß-catenin, and reducing its cytoplasmic levels in a GSK3ß- and ß-TrCP-independent manner, indicating that NEURL-ß-catenin interactions can lead to a disruption of the canonical Wnt/ß-catenin pathway. This study suggests that NEURL is a therapeutic target against human cancers and that it acts by regulating oncogenic Wnt/ß-catenin signalling.


Subject(s)
Colonic Neoplasms , beta Catenin , Humans , beta Catenin/genetics , beta Catenin/metabolism , Wnt Signaling Pathway , Colonic Neoplasms/genetics , Ubiquitin-Protein Ligases/metabolism , beta-Transducin Repeat-Containing Proteins/genetics , beta-Transducin Repeat-Containing Proteins/metabolism , Cell Line, Tumor
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