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1.
Nature ; 627(8005): 865-872, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38509377

RESUMO

Disease-associated astrocyte subsets contribute to the pathology of neurologic diseases, including multiple sclerosis and experimental autoimmune encephalomyelitis1-8 (EAE), an experimental model for multiple sclerosis. However, little is known about the stability of these astrocyte subsets and their ability to integrate past stimulation events. Here we report the identification of an epigenetically controlled memory astrocyte subset that exhibits exacerbated pro-inflammatory responses upon rechallenge. Specifically, using a combination of single-cell RNA sequencing, assay for transposase-accessible chromatin with sequencing, chromatin immunoprecipitation with sequencing, focused interrogation of cells by nucleic acid detection and sequencing, and cell-specific in vivo CRISPR-Cas9-based genetic perturbation studies we established that astrocyte memory is controlled by the metabolic enzyme ATP-citrate lyase (ACLY), which produces acetyl coenzyme A (acetyl-CoA) that is used by histone acetyltransferase p300 to control chromatin accessibility. The number of ACLY+p300+ memory astrocytes is increased in acute and chronic EAE models, and their genetic inactivation ameliorated EAE. We also detected the pro-inflammatory memory phenotype in human astrocytes in vitro; single-cell RNA sequencing and immunohistochemistry studies detected increased numbers of ACLY+p300+ astrocytes in chronic multiple sclerosis lesions. In summary, these studies define an epigenetically controlled memory astrocyte subset that promotes CNS pathology in EAE and, potentially, multiple sclerosis. These findings may guide novel therapeutic approaches for multiple sclerosis and other neurologic diseases.


Assuntos
Astrócitos , Encefalomielite Autoimune Experimental , Memória Epigenética , Esclerose Múltipla , Animais , Feminino , Humanos , Masculino , Camundongos , Acetilcoenzima A/metabolismo , Astrócitos/enzimologia , Astrócitos/metabolismo , Astrócitos/patologia , ATP Citrato (pro-S)-Liase/metabolismo , Cromatina/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Sequenciamento de Cromatina por Imunoprecipitação , Sistemas CRISPR-Cas , Encefalomielite Autoimune Experimental/enzimologia , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Inflamação/enzimologia , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Esclerose Múltipla/enzimologia , Esclerose Múltipla/genética , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Análise da Expressão Gênica de Célula Única , Transposases/metabolismo
2.
Brief Bioinform ; 25(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38305456

RESUMO

Protein structure prediction is a longstanding issue crucial for identifying new drug targets and providing a mechanistic understanding of protein functions. To enhance the progress in this field, a spectrum of computational methodologies has been cultivated. AlphaFold2 has exhibited exceptional precision in predicting wild-type protein structures, with performance exceeding that of other methods. However, predicting the structures of missense mutant proteins using AlphaFold2 remains challenging due to the intricate and substantial structural alterations caused by minor sequence variations in the mutant proteins. Molecular dynamics (MD) has been validated for precisely capturing changes in amino acid interactions attributed to protein mutations. Therefore, for the first time, a strategy entitled 'MoDAFold' was proposed to improve the accuracy and reliability of missense mutant protein structure prediction by combining AlphaFold2 with MD. Multiple case studies have confirmed the superior performance of MoDAFold compared to other methods, particularly AlphaFold2.


Assuntos
Aminoácidos , Simulação de Dinâmica Molecular , Proteínas Mutantes , Reprodutibilidade dos Testes , Mutação , Conformação Proteica
3.
Genome Biol ; 25(1): 41, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38303023

RESUMO

Protein function annotation has been one of the longstanding issues in biological sciences, and various computational methods have been developed. However, the existing methods suffer from a serious long-tail problem, with a large number of GO families containing few annotated proteins. Herein, an innovative strategy named AnnoPRO was therefore constructed by enabling sequence-based multi-scale protein representation, dual-path protein encoding using pre-training, and function annotation by long short-term memory-based decoding. A variety of case studies based on different benchmarks were conducted, which confirmed the superior performance of AnnoPRO among available methods. Source code and models have been made freely available at: https://github.com/idrblab/AnnoPRO and https://zenodo.org/records/10012272.


Assuntos
Aprendizado Profundo , Humanos , Biologia Computacional/métodos , Proteínas/metabolismo , Software , Anotação de Sequência Molecular
4.
bioRxiv ; 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38352498

RESUMO

Cancer development and progression are generally associated with dysregulation of gene expression, often resulting from changes in transcription factor (TF) sequence or expression. Identifying key TFs involved in cancer gene regulation provides a framework for potential new therapeutics. This study presents a large-scale cancer gene TF-DNA interaction network as well as an extensive promoter clone resource for future studies. Most highly connected TFs do not show a preference for binding to promoters of genes associated with either good or poor cancer prognosis, suggesting that emerging strategies aimed at shifting gene expression balance between these two prognostic groups may be inherently complex. However, we identified potential for oncogene targeted therapeutics, with half of the tested oncogenes being potentially repressed by influencing specific activator or bifunctional TFs. Finally, we investigate the role of intrinsically disordered regions within the key cancer-related TF estrogen receptor ɑ (ESR1) on DNA binding and transcriptional activity, and found that these regions can have complex trade-offs in TF function. Altogether, our study not only broadens our knowledge of TFs involved in the cancer gene regulatory network but also provides a valuable resource for future studies, laying a foundation for potential therapeutic strategies targeting TFs in cancer.

5.
bioRxiv ; 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38260616

RESUMO

Astrocytes play important roles in the central nervous system (CNS) physiology and pathology. Indeed, astrocyte subsets defined by specific transcriptional activation states contribute to the pathology of neurologic diseases, including multiple sclerosis (MS) and its pre-clinical model experimental autoimmune encephalomyelitis (EAE) 1-8 . However, little is known about the stability of these disease-associated astrocyte subsets, their regulation, and whether they integrate past stimulation events to respond to subsequent challenges. Here, we describe the identification of an epigenetically controlled memory astrocyte subset which exhibits exacerbated pro-inflammatory responses upon re-challenge. Specifically, using a combination of single-cell RNA sequencing (scRNA-seq), assay for transposase-accessible chromatin with sequencing (ATAC-seq), chromatin immunoprecipitation with sequencing (ChIP-seq), focused interrogation of cells by nucleic acid detection and sequencing (FIND-seq), and cell-specific in vivo CRISPR/Cas9-based genetic perturbation studies we established that astrocyte memory is controlled by the metabolic enzyme ATP citrate lyase (ACLY), which produces acetyl coenzyme A (acetyl-CoA) used by the histone acetyltransferase p300 to control chromatin accessibility. ACLY + p300 + memory astrocytes are increased in acute and chronic EAE models; the genetic targeting of ACLY + p300 + astrocytes using CRISPR/Cas9 ameliorated EAE. We also detected responses consistent with a pro-inflammatory memory phenotype in human astrocytes in vitro ; scRNA-seq and immunohistochemistry studies detected increased ACLY + p300 + astrocytes in chronic MS lesions. In summary, these studies define an epigenetically controlled memory astrocyte subset that promotes CNS pathology in EAE and, potentially, MS. These findings may guide novel therapeutic approaches for MS and other neurologic diseases.

6.
Int J Mol Sci ; 25(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38256101

RESUMO

Actinobacillus pleuropneumoniae (APP) is responsible for causing Porcine pleuropneumonia (PCP) in pigs. However, using vaccines and antibiotics to prevent and control this disease has become more difficult due to increased bacterial resistance and weak cross-immunity between different APP types. Naringin (NAR), a dihydroflavonoid found in citrus fruit peels, has been recognized as having significant therapeutic effects on inflammatory diseases of the respiratory system. In this study, we investigated the effects of NAR on the inflammatory response caused by APP through both in vivo and in vitro models. The results showed that NAR reduced the number of neutrophils (NEs) in the bronchoalveolar lavage fluid (BALF), and decreased lung injury and the expression of proteins related to the NLRP3 inflammasome after exposure to APP. In addition, NAR inhibited the nuclear translocation of nuclear factor kappa-B (NF-κB) P65 in porcine alveolar macrophage (PAMs), reduced protein expression of NLRP3 and Caspase-1, and reduced the secretion of pro-inflammatory cytokines induced by APP. Furthermore, NAR prevented the assembly of the NLRP3 inflammasome complex by reducing protein interaction between NLRP3, Caspase-1, and ASC. NAR also inhibited the potassium (K+) efflux induced by APP. Overall, these findings suggest that NAR can effectively reduce the lung inflammation caused by APP by inhibiting the over-activated NF-κB/NLRP3 signalling pathway, providing a basis for further exploration of NAR as a potential natural product for preventing and treating APP.


Assuntos
Actinobacillus pleuropneumoniae , Flavanonas , NF-kappa B , Animais , Suínos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Inflamassomos , Caspase 1
7.
Int J Mol Sci ; 24(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37958922

RESUMO

Critically ill patients with Corona Virus Disease 2019 (COVID-19) often develop secondary bacterial infections that pose a significant threat to patient life safety, making the development of drugs to prevent bacterial infections in the lungs critical to clinical care. Naringin (NAR) is one of the significant natural flavonoids rich in Pummelo Peel (Hua Ju Hong), with anti-inflammatory, antimicrobial, and antioxidant activities, and is commonly used in treating respiratory tract infectious diseases. In this study, the in vitro and in vivo findings revealed that, after Klebsiella pneumoniae (Kpn) infection, NAR inhibited overactivation of the nuclear factor kappa-B(NF-κB) signaling pathway in alveolar macrophages of mice, reduced neutrophil (NEs) recruitment, and lowered the induced production of proinflammatory markers, such as Interleukin-6(IL-6) and tumor necrosis factor α(TNF-α). Thus, it suppressed excessive immune responses in the lungs, as well as attenuated the induced pulmonary fibrosis and inflammatory infiltrates. These results suggest that NAR has a preventive effect against Kpn in mice. In addition, the study evaluated NAR's potential toxicity, demonstrating that NAR is safe at effective doses. These results suggested that NAR effectively reduces excessive inflammatory damage in the lungs induced by Kpn and enhances the body's ability to clear bacteria. Therefore, NAR may be an effective and safe healthcare drug for preventing and caring for bacterial pneumonia.


Assuntos
Klebsiella pneumoniae , Pneumonia Bacteriana , Camundongos , Humanos , Animais , Klebsiella pneumoniae/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Pneumonia Bacteriana/tratamento farmacológico , Fator de Necrose Tumoral alfa/metabolismo
8.
Nucleic Acids Res ; 51(21): e110, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889083

RESUMO

RNAs play essential roles in diverse physiological and pathological processes by interacting with other molecules (RNA/protein/compound), and various computational methods are available for identifying these interactions. However, the encoding features provided by existing methods are limited and the existing tools does not offer an effective way to integrate the interacting partners. In this study, a task-specific encoding algorithm for RNAs and RNA-associated interactions was therefore developed. This new algorithm was unique in (a) realizing comprehensive RNA feature encoding by introducing a great many of novel features and (b) enabling task-specific integration of interacting partners using convolutional autoencoder-directed feature embedding. Compared with existing methods/tools, this novel algorithm demonstrated superior performances in diverse benchmark testing studies. This algorithm together with its source code could be readily accessed by all user at: https://idrblab.org/corain/ and https://github.com/idrblab/corain/.


Assuntos
Biologia Computacional , RNA , RNA/genética , Biologia Computacional/métodos , Algoritmos , Software
9.
Nat Commun ; 14(1): 6570, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853017

RESUMO

Cooperativity and antagonism between transcription factors (TFs) can drastically modify their binding to regulatory DNA elements. While mapping these relationships between TFs is important for understanding their context-specific functions, existing approaches either rely on DNA binding motif predictions, interrogate one TF at a time, or study individual TFs in parallel. Here, we introduce paired yeast one-hybrid (pY1H) assays to detect cooperativity and antagonism across hundreds of TF-pairs at DNA regions of interest. We provide evidence that a wide variety of TFs are subject to modulation by other TFs in a DNA region-specific manner. We also demonstrate that TF-TF relationships are often affected by alternative isoform usage and identify cooperativity and antagonism between human TFs and viral proteins from human papillomaviruses, Epstein-Barr virus, and other viruses. Altogether, pY1H assays provide a broadly applicable framework to study how different functional relationships affect protein occupancy at regulatory DNA regions.


Assuntos
Infecções por Vírus Epstein-Barr , Fatores de Transcrição , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Ligação Proteica , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , DNA/metabolismo , Sítios de Ligação
10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 41(5): 502-511, 2023 Oct 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37805674

RESUMO

Periodontitis is a chronic inflammatory disease that destroys the integrity of tooth-supporting tissue. Periodontitis is listed as a major oral disease by the World Health Organization and is a public-health problem affecting global oral and systemic health. The fourth national oral health epidemiological survey has revealed that periodontitis is one of the most common oral problems in China. With the development of science and medicine, increased attention is being paid to the importance of oral health and its influence on general health. Accordingly, stomatologists are required to master more relevant information on clinical diagnosis and treatment, as well as to pay more attention to the diagnosis and treatment methods of patients with different systemic diseases. This article expounds the diagnosis and treatment strategy of patients with systemic disease periodontitis. We aimed to help stomatologists make more reasonable diagnosis and treatment decisions.


Assuntos
Doenças da Boca , Periodontite , Humanos , Periodontite/terapia , Saúde Bucal , China
11.
Nature ; 620(7975): 881-889, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37558878

RESUMO

Dendritic cells (DCs) have a role in the development and activation of self-reactive pathogenic T cells1,2. Genetic variants that are associated with the function of DCs have been linked to autoimmune disorders3,4, and DCs are therefore attractive therapeutic targets for such diseases. However, developing DC-targeted therapies for autoimmunity requires identification of the mechanisms that regulate DC function. Here, using single-cell and bulk transcriptional and metabolic analyses in combination with cell-specific gene perturbation studies, we identify a regulatory loop of negative feedback that operates in DCs to limit immunopathology. Specifically, we find that lactate, produced by activated DCs and other immune cells, boosts the expression of NDUFA4L2 through a mechanism mediated by hypoxia-inducible factor 1α (HIF-1α). NDUFA4L2 limits the production of mitochondrial reactive oxygen species that activate XBP1-driven transcriptional modules in DCs that are involved in the control of pathogenic autoimmune T cells. We also engineer a probiotic that produces lactate and suppresses T cell autoimmunity through the activation of HIF-1α-NDUFA4L2 signalling in DCs. In summary, we identify an immunometabolic pathway that regulates DC function, and develop a synthetic probiotic for its therapeutic activation.


Assuntos
Doenças Autoimunes , Sistema Nervoso Central , Células Dendríticas , Subunidade alfa do Fator 1 Induzível por Hipóxia , Ácido Láctico , Humanos , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Doenças Autoimunes/prevenção & controle , Autoimunidade , Sistema Nervoso Central/citologia , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/patologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/química , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácido Láctico/metabolismo , Probióticos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T/imunologia , Retroalimentação Fisiológica , Lactase/genética , Lactase/metabolismo , Análise de Célula Única
12.
Bioinformatics ; 39(7)2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37399102

RESUMO

MOTIVATION: With the rapid advances of RNA sequencing and microarray technologies in non-coding RNA (ncRNA) research, functional tools that perform enrichment analysis for ncRNAs are needed. On the one hand, because of the rapidly growing interest in circRNAs, snoRNAs, and piRNAs, it is essential to develop tools for enrichment analysis for these newly emerged ncRNAs. On the other hand, due to the key role of ncRNAs' interacting target in the determination of their function, the interactions between ncRNA and its corresponding target should be fully considered in functional enrichment. Based on the ncRNA-mRNA/protein-function strategy, some tools have been developed to functionally analyze a single type of ncRNA (the majority focuses on miRNA); in addition, some tools adopt predicted target data and lead to only low-confidence results. RESULTS: Herein, an online tool named RNAenrich was developed to enable the comprehensive and accurate enrichment analysis of ncRNAs. It is unique in (i) realizing the enrichment analysis for various RNA types in humans and mice, such as miRNA, lncRNA, circRNA, snoRNA, piRNA, and mRNA; (ii) extending the analysis by introducing millions of experimentally validated data of RNA-target interactions as a built-in database; and (iii) providing a comprehensive interacting network among various ncRNAs and targets to facilitate the mechanistic study of ncRNA function. Importantly, RNAenrich led to a more comprehensive and accurate enrichment analysis in a COVID-19-related miRNA case, which was largely attributed to its coverage of comprehensive ncRNA-target interactions. AVAILABILITY AND IMPLEMENTATION: RNAenrich is now freely accessible at https://idrblab.org/rnaenr/.


Assuntos
COVID-19 , MicroRNAs , RNA Longo não Codificante , Humanos , Animais , Camundongos , RNA não Traduzido/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Nucleolar Pequeno , RNA Mensageiro/genética , RNA Circular
13.
Nature ; 619(7969): 348-356, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37344597

RESUMO

The role of B cells in anti-tumour immunity is still debated and, accordingly, immunotherapies have focused on targeting T and natural killer cells to inhibit tumour growth1,2. Here, using high-throughput flow cytometry as well as bulk and single-cell RNA-sequencing and B-cell-receptor-sequencing analysis of B cells temporally during B16F10 melanoma growth, we identified a subset of B cells that expands specifically in the draining lymph node over time in tumour-bearing mice. The expanding B cell subset expresses the cell surface molecule T cell immunoglobulin and mucin domain 1 (TIM-1, encoded by Havcr1) and a unique transcriptional signature, including multiple co-inhibitory molecules such as PD-1, TIM-3, TIGIT and LAG-3. Although conditional deletion of these co-inhibitory molecules on B cells had little or no effect on tumour burden, selective deletion of Havcr1 in B cells both substantially inhibited tumour growth and enhanced effector T cell responses. Loss of TIM-1 enhanced the type 1 interferon response in B cells, which augmented B cell activation and increased antigen presentation and co-stimulation, resulting in increased expansion of tumour-specific effector T cells. Our results demonstrate that manipulation of TIM-1-expressing B cells enables engagement of the second arm of adaptive immunity to promote anti-tumour immunity and inhibit tumour growth.


Assuntos
Linfócitos B , Melanoma , Animais , Camundongos , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Ativação Linfocitária , Melanoma/imunologia , Melanoma/patologia , Melanoma/prevenção & controle , Linfócitos T/citologia , Linfócitos T/imunologia , Citometria de Fluxo , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Linfonodos/citologia , Linfonodos/imunologia , Apresentação de Antígeno , Receptores de Antígenos de Linfócitos B/genética , Análise da Expressão Gênica de Célula Única , Carga Tumoral , Interferon Tipo I
14.
bioRxiv ; 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36993446

RESUMO

Dendritic cells (DCs) control the generation of self-reactive pathogenic T cells. Thus, DCs are considered attractive therapeutic targets for autoimmune diseases. Using single-cell and bulk transcriptional and metabolic analyses in combination with cell-specific gene perturbation studies we identified a negative feedback regulatory pathway that operates in DCs to limit immunopathology. Specifically, we found that lactate, produced by activated DCs and other immune cells, boosts NDUFA4L2 expression through a mechanism mediated by HIF-1α. NDUFA4L2 limits the production of mitochondrial reactive oxygen species that activate XBP1-driven transcriptional modules in DCs involved in the control of pathogenic autoimmune T cells. Moreover, we engineered a probiotic that produces lactate and suppresses T-cell autoimmunity in the central nervous system via the activation of HIF-1α/NDUFA4L2 signaling in DCs. In summary, we identified an immunometabolic pathway that regulates DC function, and developed a synthetic probiotic for its therapeutic activation.

15.
Science ; 379(6636): 1023-1030, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36893254

RESUMO

Cell-cell interactions in the central nervous system play important roles in neurologic diseases. However, little is known about the specific molecular pathways involved, and methods for their systematic identification are limited. Here, we developed a forward genetic screening platform that combines CRISPR-Cas9 perturbations, cell coculture in picoliter droplets, and microfluidic-based fluorescence-activated droplet sorting to identify mechanisms of cell-cell communication. We used SPEAC-seq (systematic perturbation of encapsulated associated cells followed by sequencing), in combination with in vivo genetic perturbations, to identify microglia-produced amphiregulin as a suppressor of disease-promoting astrocyte responses in multiple sclerosis preclinical models and clinical samples. Thus, SPEAC-seq enables the high-throughput systematic identification of cell-cell communication mechanisms.


Assuntos
Anfirregulina , Astrócitos , Comunicação Autócrina , Testes Genéticos , Técnicas Analíticas Microfluídicas , Microglia , Astrócitos/fisiologia , Testes Genéticos/métodos , Ensaios de Triagem em Larga Escala , Técnicas Analíticas Microfluídicas/métodos , Microglia/fisiologia , Anfirregulina/genética , Comunicação Autócrina/genética , Expressão Gênica , Humanos
16.
Food Chem ; 413: 135530, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36758386

RESUMO

The current study was aimed to enhance the solubility, dispersibility and biotransformation efficacy of ellagic acid (EA) by preparing food-derived ellagic acid-Undaria pinnatifida polysaccharides solid dispersion (EA/UPP SD). The results demonstrated that the solubility of EA/UPP SD was improved from 0.014 mg/mL to 0.383 mg/mL, and the enhancement was related to converting to a more amorphous state and restraining its self-aggregation during the mechanochemical process. The structure of EA/UPP SDs was mostly maintained by hydrogen bonds and hydrophobic interactions between EA and UPP. Moreover, the result of in vitro anaerobic incubations showed the biotransformation process was improved with EA/UPP SD addition to substrate due to the advance of microbial accessibility in EA dispersion. Altogether, these results indicated that the EA/UPP SDs expanded the application of EA by increasing the solubility and dispersity, and provided a theoretical basis for bioconversion efficiency enhancement.


Assuntos
Ácido Elágico , Undaria , Ácido Elágico/química , Undaria/química , Solubilidade , Polissacarídeos/química
17.
Nature ; 614(7947): 326-333, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36599367

RESUMO

Multiple sclerosis is a chronic inflammatory disease of the central nervous system1. Astrocytes are heterogeneous glial cells that are resident in the central nervous system and participate in the pathogenesis of multiple sclerosis and its model experimental autoimmune encephalomyelitis2,3. However, few unique surface markers are available for the isolation of astrocyte subsets, preventing their analysis and the identification of candidate therapeutic targets; these limitations are further amplified by the rarity of pathogenic astrocytes. Here, to address these challenges, we developed focused interrogation of cells by nucleic acid detection and sequencing (FIND-seq), a high-throughput microfluidic cytometry method that combines encapsulation of cells in droplets, PCR-based detection of target nucleic acids and droplet sorting to enable in-depth transcriptomic analyses of cells of interest at single-cell resolution. We applied FIND-seq to study the regulation of astrocytes characterized by the splicing-driven activation of the transcription factor XBP1, which promotes disease pathology in multiple sclerosis and experimental autoimmune encephalomyelitis4. Using FIND-seq in combination with conditional-knockout mice, in vivo CRISPR-Cas9-driven genetic perturbation studies and bulk and single-cell RNA sequencing analyses of samples from mouse experimental autoimmune encephalomyelitis and humans with multiple sclerosis, we identified a new role for the nuclear receptor NR3C2 and its corepressor NCOR2 in limiting XBP1-driven pathogenic astrocyte responses. In summary, we used FIND-seq to identify a therapeutically targetable mechanism that limits XBP1-driven pathogenic astrocyte responses. FIND-seq enables the investigation of previously inaccessible cells, including rare cell subsets defined by unique gene expression signatures or other nucleic acid markers.


Assuntos
Astrócitos , Encefalomielite Autoimune Experimental , Microfluídica , Esclerose Múltipla , Ácidos Nucleicos , Análise da Expressão Gênica de Célula Única , Animais , Humanos , Camundongos , Astrócitos/metabolismo , Astrócitos/patologia , Regulação da Expressão Gênica , Camundongos Knockout , Esclerose Múltipla/patologia , Microfluídica/métodos , Análise da Expressão Gênica de Célula Única/métodos , Ácidos Nucleicos/análise , Edição de Genes
18.
Nucleic Acids Res ; 51(D1): D1288-D1299, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36243961

RESUMO

The efficacy and safety of drugs are widely known to be determined by their interactions with multiple molecules of pharmacological importance, and it is therefore essential to systematically depict the molecular atlas and pharma-information of studied drugs. However, our understanding of such information is neither comprehensive nor precise, which necessitates the construction of a new database providing a network containing a large number of drugs and their interacting molecules. Here, a new database describing the molecular atlas and pharma-information of drugs (DrugMAP) was therefore constructed. It provides a comprehensive list of interacting molecules for >30 000 drugs/drug candidates, gives the differential expression patterns for >5000 interacting molecules among different disease sites, ADME (absorption, distribution, metabolism and excretion)-relevant organs and physiological tissues, and weaves a comprehensive and precise network containing >200 000 interactions among drugs and molecules. With the great efforts made to clarify the complex mechanism underlying drug pharmacokinetics and pharmacodynamics and rapidly emerging interests in artificial intelligence (AI)-based network analyses, DrugMAP is expected to become an indispensable supplement to existing databases to facilitate drug discovery. It is now fully and freely accessible at: https://idrblab.org/drugmap/.


Assuntos
Inteligência Artificial , Descoberta de Drogas , Bases de Dados Factuais , Preparações Farmacêuticas , Atlas como Assunto
19.
Front Immunol ; 13: 956907, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505477

RESUMO

Background: Parenteral anti-CD3 Mab (OKT3) has been used to treat transplant rejection and parental administration of a humanized anti-CD3 Mab (Teplizumab) showed positive effects in diabetes. Nasal administration of anti-CD3 Mab has not been carried out in humans. Nasal anti-CD3 Mab suppresses autoimmune diseases and central nervous system (CNS) inflammation in animal models. We investigated the safety and immune effects of a fully humanized, previously uncharacterized nasal anti-CD3 Mab (Foralumab) in humans and its in vitro stimulatory properties. Methods: In vitro, Foralumab were compared to UCHT1 anti-human CD3 mAb. For human administration, 27 healthy volunteers (9 per group) received nasal Foralumab or placebo at a dose of 10ug, 50ug, or 250ug daily for 5 days. Safety was assessed and immune parameters measured on day 1 (pre-treatment), 7, 14, and 30 by FACS and by scRNAseq. Results: In vitro, Foralumab preferentially induced CD8+ T cell stimulation, reduced CD4+ T cell proliferation and lowered expression of IFNg, IL-17 and TNFa. Foralumab induced LAP, TIGIT, and KLRG1 immune checkpoint molecules on CD8+ and CD4+ T cells in a mechanism independent of CD8 T cells. In vivo, nasal Foralumab did not modulate CD3 from the T cell surface at any dose. Immune effects were primarily observed at the 50ug dose and consisted of reduction of CD8+ effector memory cells, an increase in naive CD8+ and CD4+ T cells, and reduced CD8+ T cell granzyme B and perforin expression. Differentially expressed genes observed by scRNAseq in CD8+ and CD4+ populations promoted survival and were anti-inflammatory. In the CD8+ TEMRA population there was induction of TIGIT, TGFB1 and KIR3DL2, indicative of a regulatory phenotype. In the memory CD4+ population, there was induction of CTLA4, KLRG1, and TGFB whereas there was an induction of TGF-B1 in naïve CD4+ T cells. In monocytes, there was induction of genes (HLA-DP, HLA-DQ) that promote a less inflammatory immune response. No side effects were observed, and no subjects developed human anti-mouse antibodies. Conclusion: These findings demonstrate that nasal Foralumab is safe and immunologically active in humans and presents a new avenue for the treatment of autoimmune and CNS diseases.


Assuntos
Anticorpos Monoclonais , Linfócitos T CD8-Positivos , Humanos , Administração Intranasal , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Muromonab-CD3 , Sujeitos da Pesquisa
20.
Nanotechnology ; 34(5)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36327458

RESUMO

To explore low-cost, high-efficiency, and noble-metal-free catalysts for electrocatalytic water splitting in both acidic and alkaline media, the metal-metal carbide Janus hierarchical structure comprising Mo andß-Mo2C embedded on a carbon layer (Mo/ß-Mo2C)@C is synthesized by a hydrothermal reaction and subsequent low-temperature magnesium thermic process. Systematic characterization by XRD, XPS, Raman scattering, and SEM/TEM reveals the successful formation of metallic Mo andß-Mo2C nanoparticles. The synthesized (Mo/ß-Mo2C)@C has a large specific surface area and boasts highly efficient hydrogen evolution reaction activity including low overpotentials of 152 and 171 mV at a current density of 10 mA cm-2and small Tafel slopes of 51.7 and 63.5 mV dec-1in acidic and alkaline media, respectively. In addition, the catalyst shows outstanding stability for 48 h in both acidic and alkaline media. The excellent catalytic activity originates from more active sites and greater electron conductivity bestowed by the carbon layer, which also improves the long-term stability in both acidic and alkaline solutions.

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