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1.
Nat Immunol ; 25(4): 622-632, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38454157

RESUMO

The development of a vaccine specific to severe acute respiratory syndrome coronavirus 2 Omicron has been hampered due to its low immunogenicity. Here, using reverse mutagenesis, we found that a phenylalanine-to-serine mutation at position 375 (F375S) in the spike protein of Omicron to revert it to the sequence found in Delta and other ancestral strains significantly enhanced the immunogenicity of Omicron vaccines. Sequence FAPFFAF at position 371-377 in Omicron spike had a potent inhibitory effect on macrophage uptake of receptor-binding domain (RBD) nanoparticles or spike-pseudovirus particles containing this sequence. Omicron RBD enhanced binding to Siglec-9 on macrophages to impair phagocytosis and antigen presentation and promote immune evasion, which could be abrogated by the F375S mutation. A bivalent F375S Omicron RBD and Delta-RBD nanoparticle vaccine elicited potent and broad nAbs in mice, rabbits and rhesus macaques. Our research suggested that manipulation of the Siglec-9 pathway could be a promising approach to enhance vaccine response.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Camundongos , Coelhos , Anticorpos Neutralizantes , Anticorpos Antivirais , Macaca mulatta , Macrófagos , Nanovacinas , Fagocitose , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico
2.
Immunity ; 53(6): 1315-1330.e9, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33275896

RESUMO

Various vaccine strategies have been proposed in response to the global COVID-19 pandemic, each with unique strategies for eliciting immune responses. Here, we developed nanoparticle vaccines by covalently conjugating the self-assembled 24-mer ferritin to the receptor binding domain (RBD) and/or heptad repeat (HR) subunits of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) spike (S) protein. Compared to monomer vaccines, nanoparticle vaccines elicited more robust neutralizing antibodies and cellular immune responses. RBD and RBD-HR nanoparticle vaccinated hACE2 transgenic mice vaccinated with RBD and/or RBD-HR nanoparticles exhibited reduced viral load in the lungs after SARS-CoV-2 challenge. RBD-HR nanoparticle vaccines also promoted neutralizing antibodies and cellular immune responses against other coronaviruses. The nanoparticle vaccination of rhesus macaques induced neutralizing antibodies, and T and B cell responses prior to boost immunization; these responses persisted for more than three months. RBD- and HR-based nanoparticles thus present a promising vaccination approach against SARS-CoV-2 and other coronaviruses.


Assuntos
Proteínas de Bactérias/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , Ferritinas/imunologia , Helicobacter pylori/metabolismo , Proteínas Recombinantes de Fusão/imunologia , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/metabolismo , Proteínas de Bactérias/química , Vacinas contra COVID-19/química , Ferritinas/química , Humanos , Macaca mulatta , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Pandemias , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/química , Vacinação
3.
Plant Cell ; 35(2): 910-923, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36503931

RESUMO

DNA replication stress threatens genome stability and affects plant growth and development. How plants resolve replication stress is poorly understood. The protein kinase WEE1-mediated cell cycle arrest is required for replication stress responses. The E3 ubiquitin ligases anaphase-promoting complex/cyclosome (APC/C) and Skp1/Cullin 1/F-box (SCF) are essential regulators of the cell cycle. Here, we show that APC/CCDC20 mediates the degradation of SCFFBL17 during replication stress responses in Arabidopsis thaliana. Biochemically, WEE1 interacts with and phosphorylates the APC/C co-activator APC10, which enhances the interaction between F-BOX-LIKE17 (FBL17) and CELL DIVISION CYCLE 20 (CDC20), an activator of APC/C. Both APC10 and CDC20 are required for the polyubiquitination and degradation of FBL17. Genetically, silencing CDC20 or APC10 confers plant hypersensitivity to replication stress, which is suppressed by loss of FBL17. Collectively, our study suggests that WEE1 activates APC/C to inhibit FBL17, providing insight into replication stress responses in plants.


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Ciclo Celular/fisiologia , Ciclossomo-Complexo Promotor de Anáfase/genética , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Cdc20/metabolismo
4.
Plant Cell ; 35(8): 3021-3034, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37159556

RESUMO

DNA replication stress threatens genome stability and is a hallmark of cancer in humans. The evolutionarily conserved kinases ATR (ATM and RAD3-related) and WEE1 are essential for the activation of replication stress responses. Translational control is an important mechanism that regulates gene expression, but its role in replication stress responses is largely unknown. Here we show that ATR-WEE1 control the translation of SUPPRESSOR OF GAMMA RESPONSE 1 (SOG1), a master transcription factor required for replication stress responses in Arabidopsis thaliana. Through genetic screening, we found that the loss of GENERAL CONTROL NONDEREPRESSIBLE 20 (GCN20) or GCN1, which function together to inhibit protein translation, suppressed the hypersensitivity of the atr or wee1 mutant to replication stress. Biochemically, WEE1 inhibits GCN20 by phosphorylating it; phosphorylated GCN20 is subsequently polyubiquitinated and degraded. Ribosome profiling experiments revealed that that loss of GCN20 enhanced the translation efficiency of SOG1, while overexpressing GCN20 had the opposite effect. The loss of SOG1 reduced the resistance of wee1 gcn20 to replication stress, whereas overexpressing SOG1 enhanced the resistance to atr or wee1 to replication stress. These results suggest that ATR-WEE1 inhibits GCN20-GCN1 activity to promote the translation of SOG1 during replication stress. These findings link translational control to replication stress responses in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Humanos , Fatores de Transcrição/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/genética , Dano ao DNA , Replicação do DNA/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
5.
EMBO J ; 40(10): e106632, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33739466

RESUMO

HIV-1 latency is a major obstacle to achieving a functional cure for AIDS. Reactivation of HIV-1-infected cells followed by their elimination via immune surveillance is one proposed strategy for eradicating the viral reservoir. However, current latency-reversing agents (LRAs) show high toxicity and low efficiency, and new targets are needed to develop more promising LRAs. Here, we found that the histone chaperone CAF-1 (chromatin assembly factor 1) is enriched on the HIV-1 long terminal repeat (LTR) and forms nuclear bodies with liquid-liquid phase separation (LLPS) properties. CAF-1 recruits epigenetic modifiers and histone chaperones to the nuclear bodies to establish and maintain HIV-1 latency in different latency models and primary CD4+ T cells. Three disordered regions of the CHAF1A subunit are important for phase-separated CAF-1 nuclear body formation and play a key role in maintaining HIV-1 latency. Disruption of phase-separated CAF-1 bodies could be a potential strategy to reactivate latent HIV-1.


Assuntos
HIV-1/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Fator 1 de Modelagem da Cromatina/genética , Fator 1 de Modelagem da Cromatina/metabolismo , Epigênese Genética/genética , Epigênese Genética/fisiologia , Células HEK293 , Humanos , Regiões Promotoras Genéticas/genética
6.
PLoS Pathog ; 19(11): e1011792, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37956198

RESUMO

Melanoma differentiation-associated gene-5 (MDA5) acts as a cytoplasmic RNA sensor to detect viral dsRNA and mediates antiviral innate immune responses to infection by RNA viruses. Upon recognition of viral dsRNA, MDA5 is activated with K63-linked polyubiquitination and then triggers the recruitment of MAVS and activation of TBK1 and IKKα/ß, subsequently leading to IRF3 and NF-κB phosphorylation. However, the specific E3 ubiquitin ligase for MDA5 K63-polyubiquitination has not been well characterized. Great numbers of symptomatic and severe infections of SARS-CoV-2 are spreading worldwide, and the poor efficacy of treatment with type I interferon and antiviral immune agents indicates that SARS-CoV-2 escapes from antiviral immune responses via several unknown mechanisms. Here, we report that SARS-CoV-2 nonstructural protein 8 (nsp8) acts as a suppressor of antiviral innate immune and inflammatory responses to promote infection of SARS-CoV-2. It downregulates the expression of type I interferon, IFN-stimulated genes and proinflammatory cytokines by binding to MDA5 and TRIM4 and impairing TRIM4-mediated MDA5 K63-linked polyubiquitination. Our findings reveal that nsp8 mediates innate immune evasion during SARS-CoV-2 infection and may serve as a potential target for future therapeutics for SARS-CoV-2 infectious diseases.


Assuntos
COVID-19 , Interferon Tipo I , SARS-CoV-2 , Humanos , COVID-19/genética , Imunidade Inata , Interferon Tipo I/metabolismo , Helicase IFIH1 Induzida por Interferon/genética , Helicase IFIH1 Induzida por Interferon/metabolismo , SARS-CoV-2/metabolismo , Transdução de Sinais
7.
EMBO Rep ; 24(3): e56034, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36629012

RESUMO

Interleukin 22 (IL-22) has an important role in colorectal tumorigenesis and many colorectal diseases such as inflammatory bowel disease and certain infections. However, the regulation of IL-22 production in the intestinal system is still unclear. Here, we present evidence that butyrophilin-like protein 2 (BTNL2) is required for colorectal IL-22 production, and BTNL2 knockout mice show decreased colonic tumorigenesis and more severe colitis phenotypes than control mice due to defective production of IL-22. Mechanistically, BTNL2 acts on group 3 innate lymphoid cells (ILC3s), CD4+ T cells, and γδ T cells to promote the production of IL-22. Importantly, we find that a monoclonal antibody against BTNL2 attenuates colorectal tumorigenesis in mice and that the mBTNL2-Fc recombinant protein has a therapeutic effect in a dextran sulfate sodium (DSS)-induced colitis model. This study not only identifies a regulatory mechanism of IL-22 production in the colorectal system but also provides a potential therapeutic target for the treatment of human colorectal cancer and inflammatory bowel diseases.


Assuntos
Colite , Neoplasias Colorretais , Humanos , Camundongos , Animais , Imunidade Inata , Linfócitos , Carcinogênese , Transformação Celular Neoplásica , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais de Doenças , Butirofilinas , Interleucina 22
8.
Nucleic Acids Res ; 51(19): 10752-10767, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37739415

RESUMO

G-quadruplex (G4) is a unique secondary structure formed by guanine-rich nucleic acid sequences. Growing studies reported that the genomes of some viruses harbor G4 structures associated with viral replication, opening up a new field to dissect viral infection. Porcine reproductive and respiratory syndrome virus (PRRSV), a representative member of Arteriviridae, is an economically significant pathogen that has devastated the swine industry worldwide for over 30 years. In this study, we identified a highly conserved G-rich sequence with parallel-type G4 structure (named PRRSV-G4) in the negative strand genome RNA of PRRSV. Pyridostatin (PDS), a well-known G4-binding ligand, stabilized the PRRSV-G4 structure and inhibited viral replication. By screening the proteins interacting with PRRSV-G4 in PRRSV-infected cells and single-molecule magnetic tweezers analysis, we found that two helicases, host DDX18 and viral nsp10, interact with and efficiently unwound the PRRSV-G4 structure, thereby facilitating viral replication. Using a PRRSV reverse genetics system, we confirmed that recombinant PRRSV with a G4-disruptive mutation exhibited resistance to PDS treatment, thereby displaying higher replication than wild-type PRRSV. Collectively, these results demonstrate that the PRRSV-G4 structure plays a crucial regulatory role in viral replication, and targeting this structure represents a promising strategy for antiviral therapies.


Assuntos
Vírus da Síndrome Respiratória e Reprodutiva Suína , Suínos , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Proteínas não Estruturais Virais/metabolismo , DNA Helicases/genética , Replicação Viral/genética , RNA
9.
Nucleic Acids Res ; 51(15): 7951-7971, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37395406

RESUMO

The fidelity of alternative splicing (AS) patterns is essential for growth development and cell fate determination. However, the scope of the molecular switches that regulate AS remains largely unexplored. Here we show that MEN1 is a previously unknown splicing regulatory factor. MEN1 deletion resulted in reprogramming of AS patterns in mouse lung tissue and human lung cancer cells, suggesting that MEN1 has a general function in regulating alternative precursor mRNA splicing. MEN1 altered exon skipping and the abundance of mRNA splicing isoforms of certain genes with suboptimal splice sites. Chromatin immunoprecipitation and chromosome walking assays revealed that MEN1 favored the accumulation of RNA polymerase II (Pol II) in regions encoding variant exons. Our data suggest that MEN1 regulates AS by slowing the Pol II elongation rate and that defects in these processes trigger R-loop formation, DNA damage accumulation and genome instability. Furthermore, we identified 28 MEN1-regulated exon-skipping events in lung cancer cells that were closely correlated with survival in patients with lung adenocarcinoma, and MEN1 deficiency sensitized lung cancer cells to splicing inhibitors. Collectively, these findings led to the identification of a novel biological role for menin in maintaining AS homeostasis and link this role to the regulation of cancer cell behavior.


Assuntos
Processamento Alternativo , Neoplasias Pulmonares , Animais , Humanos , Camundongos , Processamento Alternativo/genética , Instabilidade Genômica/genética , Neoplasias Pulmonares/genética , Estruturas R-Loop , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , RNA Mensageiro/metabolismo
10.
Nano Lett ; 24(21): 6433-6440, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38747334

RESUMO

Soap bubbles exhibit abundant fascinating phenomena throughout the entire life of evolution with different fundamental physics governing them. Nevertheless, the complicated dynamics of small objects in soap films are still unrevealed. Here, we report the first observation of spontaneous particle ordering in a complicated galaxy of soap films without any external energy. The balance of interfacial tension at two liquid-gas interfaces is theoretically predicted to govern belted wetted particles (BWPs) traveling along a specified path spontaneously. Such spontaneous particle path-finding is found to depend on the particle size and hydrophilic properties. Spontaneous particle sorting is directly realized via these discrete and distinctive paths for different particles. The deformation of the soap membrane facilitates 1D/2D particle organization along the path. This observation represents the discovery of a new spontaneous order phenomenon in soap film systems and provides a new energy-free approach for particle separation and soft colloidal crystal assembly.

11.
Small ; : e2402727, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958086

RESUMO

2D transition metal dichalcogenides (TMDCs) have been intensively explored in memristors for brain-inspired computing. Oxidation, which is usually unavoidable and harmful in 2D TMDCs, could also be used to enhance their memristive performances. However, it is still unclear how oxidation affects the resistive switching behaviors of 2D ambipolar TMDCs. In this work, a mild oxidation strategy is developed to greatly enhance the resistive switching ratio of ambipolar 2H-MoTe2 lateral memristors by more than 10 times. Such an enhancement results from the amplified doping due to O2 and H2O adsorption and the optimization of effective gate voltage distribution by mild oxidation. Moreover, the ambipolarity of 2H-MoTe2 also enables a change of resistive switching direction, which is uncommon in 2D memristors. Consequently, as an artificial synapse, the MoTe2 device exhibits a large dynamic range (≈200) and a good linearity (1.01) in long-term potentiation and depression, as well as a high-accuracy handwritten digit recognition (>96%). This work not only provides a feasible and effective way to enhance the memristive performance of 2D ambipolar materials, but also deepens the understanding of hidden mechanisms for RS behaviors in oxidized 2D materials.

12.
J Transl Med ; 22(1): 37, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191424

RESUMO

BACKGROUND: Aberrant intracellular or intercellular signaling pathways are important mechanisms that contribute to the development and progression of cancer. However, the intercellular communication associated with the development of ccRCC is currently unknown. The purpose of this study was to examine the aberrant tumor cell-to-cell communication signals during the development of ccRCC. METHODS: We conducted an analysis on the scRNA-seq data of 6 ccRCC and 6 normal kidney tissues. This analysis included sub clustering, CNV analysis, single-cell trajectory analysis, cell-cell communication analysis, and transcription factor analysis. Moreover, we performed validation tests on clinical samples using multiplex immunofluorescence. RESULTS: This study identified eleven aberrantly activated intercellular signaling pathways in tumor clusters from ccRCC samples. Among these, two of the majors signaling molecules, MIF and SPP1, were mainly secreted by a subpopulation of cancer stem cells. This subpopulation demonstrated high expression levels of the cancer stem cell markers POU5F1 and CD44 (POU5F1hiCD44hiE.T), with the transcription factor POU5F1 regulating the expression of SPP1. Further research demonstrated that SPP1 binds to integrin receptors on the surface of target cells and promotes ccRCC development and progression by activating potential signaling mechanisms such as ILK and JAK/STAT. CONCLUSION: Aberrantly activated tumor intercellular signaling pathways promote the development and progression of ccRCC. The cancer stem cell subpopulation (POU5F1hiCD44hiE.T) promotes malignant transformation and the development of a malignant phenotype by releasing aberrant signaling molecules and interacting with other tumor cells.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/genética , Transcriptoma/genética , Transdução de Sinais/genética , Comunicação Celular , Neoplasias Renais/genética
13.
Int J Med Microbiol ; 315: 151624, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838390

RESUMO

Staphylococcus aureus is a notorious pathogen responsible for various severe diseases. Due to the emergence of drug-resistant strains, the prevention and treatment of S. aureus infections have become increasingly challenging. Vancomycin is considered to be one of the last-resort drugs for treating most methicillin-resistant S. aureus (MRSA), so it is of great significance to further reveal the mechanism of vancomycin resistance. VraFG is one of the few important ABC (ATP-binding cassette) transporters in S. aureus that can form TCS (two-component systems)/ABC transporter modules. ABC transporters can couple the energy released from ATP hydrolysis to translocate solutes across the cell membrane. In this study, we obtained a strain with decreased vancomycin susceptibility after serial passaging and selection. Subsequently, whole-genome sequencing was performed on this laboratory-derived strain MWA2 and a novel single point mutation was discovered in vraF gene, leading to decreased sensitivity to vancomycin and daptomycin. Furthermore, the mutation reduces autolysis of S. aureus and downregulates the expression of lytM, isaA, and atlA. Additionally, we observed that the mutant has a less net negative surface charge than wild-type strain. We also noted an increase in the expression of the dlt operon and mprF gene, which are associated with cell surface charge and serve to hinder the binding of cationic peptides by promoting electrostatic repulsion. Moreover, this mutation has been shown to enhance hemolytic activity, expand subcutaneous abscesses, reflecting an increased virulence. This study confirms the impact of a point mutation of VraF on S. aureus antibiotic resistance and virulence, contributing to a broader understanding of ABC transporter function and providing new targets for treating S. aureus infections.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Antibacterianos , Proteínas de Bactérias , Infecções Estafilocócicas , Staphylococcus aureus , Vancomicina , Virulência/genética , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Vancomicina/farmacologia , Animais , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/metabolismo , Testes de Sensibilidade Microbiana , Resistência a Vancomicina/genética , Sequenciamento Completo do Genoma , Daptomicina/farmacologia , Camundongos , Autólise , Humanos , Mutação Puntual , Mutação , Feminino
14.
Exp Eye Res ; 243: 109912, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670210

RESUMO

Diabetic retinopathy (DR), a most common microangiopathy of diabetes, causes vision loss and even blindness. The mechanisms of exosomal lncRNA remain unclear in the development of DR. Here, we first identifed the pro-angiogenic effect of exosomes derived from vitreous humor of proliferative diabetic retinopathy patients, where lncRNA-MIAT was enriched inside. Secondly, lncRNA-MIAT was demonstrated significantly increased in exosomes from high glucose induced human retinal vascular endothelial cell, and can regulate tube formation, migration and proliferation ability to promote angiogenesis in vitro and in vivo. Mechanistically, the pro-angiogenic effect of lncRNA-MIAT was via the lncRNA-MIAT/miR-133a-3p/MMP-X1 axis. The reduced level of lncRNA-MIAT in this axis mitigated the generation of retinal neovascular in mouse model of oxygen-induced retinopathy (OIR), providing crucial evidence for lncRNA-MIAT as a potential clinical target. These findings enhance our understanding of the role of exosomal lncRNA-MIAT in retinal angiogenesis, and propose a promising therapeutic strategy against diabetic retinopathy.


Assuntos
Retinopatia Diabética , Exossomos , MicroRNAs , RNA Longo não Codificante , Neovascularização Retiniana , Animais , Humanos , Masculino , Camundongos , Movimento Celular , Proliferação de Células , Células Cultivadas , Diabetes Mellitus Experimental , Retinopatia Diabética/metabolismo , Retinopatia Diabética/genética , Retinopatia Diabética/patologia , Modelos Animais de Doenças , Exossomos/metabolismo , Exossomos/genética , Regulação da Expressão Gênica , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/genética , Neovascularização Retiniana/patologia , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia , RNA Longo não Codificante/genética
15.
Exp Eye Res ; 241: 109837, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382576

RESUMO

The lens is an avascular tissue, where epithelial cells (LECs) are the primary living cells. The role of LECs-derived exosomes (LEC-exos) is largely unknown. In our study, we determined the anti-angiogenic role of LEC-exos, manifested as regressed retinal neovascularization (NV) using the oxygen-induced retinopathy (OIR), and reduced choroidal NV size and pathological vascular leakage using the laser-induced choroidal neovascularization (laser-induced CNV). Furthermore, the activation and accumulation of microglia were also restricted by LEC-exos. Based on Luminex multiplex assays, the expressions of chemokines such as SCYB16/CXCL16, MCP-1/CCL2, I-TAC/CXCL11, and MIP 3beta/CCL19 were decreased after treatment with LEC-exos. Transwell assays showed that LEC-exos restricted the migration of the mouse microglia cell line (BV2 cells). After incubation with LEC-exos-treated BV2 cells, human umbilical vein endothelial cells (hUVECs) were collected for further evaluation using tube formation, Transwell assays, and 5-ethynyl-2'-deoxyuridine (EDU) assays. Using in vitro experiments, the pro-angiogenic effect of microglia was restricted by LEC-exos. Hence, it was investigated that LEC-exos attenuated ocular NV, which might attribute to the inhibition of microglial activation and accumulation.


Assuntos
Neovascularização de Coroide , Exossomos , Células-Tronco Mesenquimais , Camundongos , Animais , Humanos , Microglia , Exossomos/metabolismo , Angiogênese , Neovascularização Fisiológica/fisiologia , Células Endoteliais da Veia Umbilical Humana , Neovascularização de Coroide/metabolismo
16.
FASEB J ; 37(10): e23192, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37682530

RESUMO

Abnormal ocular neovascularization, a major pathology of eye diseases, leads to severe visual loss. The role of lens epithelial cell (LEC)-derived exosomes (Lec-exo) is largely unknown. Thus, we aimed to investigate whether Lec-exo can inhibit abnormal ocular neovascularization and explore the possible mechanisms. In our study, we proved the first evidence that exosomes derived from LECs attenuated angiogenesis in both oxygen-induced retinopathy and laser-induced choroidal neovascularization mice models. Further in vitro experiments proved that Lec-exo inhibited proliferation, migration, and tube formation capability of human umbilical vein endothelial cells in high glucose condition. Further high-throughput miRNAs sequencing analysis detected that miR-146a-5p was enriched in Lec-exo. Mechanistically, exosomal miR-146a-5p was delivered to endothelial cells and bound to the NRAS coding sequence, which subsequently inactivated AKT/ERK signaling pathway. We successfully elucidated the function of Lec-exo in inhibiting abnormal ocular neovascularization, which may offer a promising strategy for treatment of abnormal ocular neovascularization.


Assuntos
Neovascularização de Coroide , Exossomos , MicroRNAs , Humanos , Animais , Camundongos , Células Epiteliais , Neovascularização de Coroide/genética , Células Endoteliais da Veia Umbilical Humana , MicroRNAs/genética
17.
Langmuir ; 40(5): 2567-2576, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38267385

RESUMO

In this study, researchers developed a novel composite material called NH2-MIL-53-Al/PAN, which consists of metal-organic frameworks (MOFs) grown on electrospun PAN nanofibers (NFs). The successful formation of the composite was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR), and the hydrophilicity of NH2-MIL-53-Al/PAN was demonstrated by the water contact angle (WCA). Batch experiments were conducted to investigate the adsorption performance of Co(II) under different conditions. The maximum adsorption capacity reached 58.72 mg/g, and almost 95% of the adsorption was achieved within the first 6 h. The adsorption process was found to be spontaneous and endothermic and followed the pseudo-second-order kinetics and Langmuir models. Chemisorption and molecular layer adsorption are the main mechanisms of adsorption, and X-ray photoelectron spectroscopy (XPS) analysis further reveals that the interaction between the adsorbent and cobalt is a coordination interaction. In this study, NH2-MIL-53-Al was grown in situ on PAN to ensure effective loading of MOFs and prevent agglomeration during the NF mixing process. This approach successfully addressed the challenge of exposing active sites within the embedded MOF crystals. Additionally, it overcame the difficulty of recycling traditional MOF adsorbents. As a result, the exceptional performance of MOF NFs offers a promising solution for the efficient removal of cobalt-containing wastewater.

18.
EMBO Rep ; 23(7): e53855, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35642598

RESUMO

The retrovirus HIV-1 integrates into the host genome and establishes a latent viral reservoir that escapes immune surveillance. Molecular mechanisms of HIV-1 latency have been studied extensively to achieve a cure for the acquired immunodeficiency syndrome (AIDS). Latency-reversing agents (LRAs) have been developed to reactivate and eliminate the latent reservoir by the immune system. To develop more promising LRAs, it is essential to evaluate new therapeutic targets. Here, we find that CBX4, a component of the Polycomb Repressive Complex 1 (PRC1), contributes to HIV-1 latency in seven latency models and primary CD4+ T cells. CBX4 forms nuclear bodies with liquid-liquid phase separation (LLPS) properties on the HIV-1 long terminal repeat (LTR) and recruits EZH2, the catalytic subunit of PRC2. CBX4 SUMOylates EZH2 utilizing its SUMO E3 ligase activity, thereby enhancing the H3K27 methyltransferase activity of EZH2. Our results indicate that CBX4 acts as a bridge between the repressor complexes PRC1 and PRC2 that act synergistically to maintain HIV-1 latency. Dissolution of phase-separated CBX4 bodies could be a potential intervention to reactivate latent HIV-1.


Assuntos
Infecções por HIV , HIV-1 , Linfócitos T CD4-Positivos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , HIV-1/genética , Humanos , Ligases , Corpos Nucleares , Complexo Repressor Polycomb 1 , Proteínas do Grupo Polycomb/genética , Latência Viral/genética
19.
J Immunol ; 209(9): 1796-1805, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36130827

RESUMO

The receptor tyrosine kinase EPHB2 (EPH receptor B2) is highly expressed in many human cancer types, especially in gastrointestinal cancers, such as colorectal cancer. Several coding mutations of the EPHB2 gene have been identified in many cancer types, suggesting that EPHB2 plays a critical role in carcinogenesis. However, the exact functional mechanism of EPHB2 in carcinogenesis remains unknown. In this study, we find that EPHB2 is required for TNF-induced signaling activation and proinflammatory cytokine production in colorectal epithelial cells. Mechanistically, after TNF stimulation, EPHB2 is ubiquitinated by its E3 ligase RNF186. Then, ubiquitinated EPHB2 recruits and further phosphorylates TAB2 at nine tyrosine sites, which is a critical step for the binding between TAB2 and TAK1. Due to defects in TNF signaling in RNF186-knockout colorectal epithelial cells, the phenotype of colitis-propelled colorectal cancer model in RNF186-knockout mice is significantly reduced compared with that in wild-type control mice. Moreover, we find that a genetic mutation in EPHB2 identified in a family with colorectal cancer is a gain-of-function mutation that promoted TNF signaling activation compared with wild-type EPHB2. We provide evidence that the EPHB2-RNF186-TAB2-TAK1 signaling cascade plays an essential role in TNF-mediated signal transduction in colorectal epithelial cells and the carcinogenesis of colorectal cancer, which may provide potential targets for the treatment of colorectal cancer.


Assuntos
Neoplasias Colorretais , Receptor EphA1 , Animais , Humanos , Camundongos , Carcinogênese , Neoplasias Colorretais/genética , Citocinas , Células Epiteliais/metabolismo , Receptor EphA1/metabolismo , Transdução de Sinais , Tirosina , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Receptor EphB2
20.
J Nanobiotechnology ; 22(1): 391, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965509

RESUMO

BACKGROUND: Prostate cancer (PCa) has a high incidence in men worldwide, and almost all PCa patients progress to the androgen-independent stage which lacks effective treatment measures. PTENP1, a long non-coding RNA, has been shown to suppress tumor growth through the rescuing of PTEN expression via a competitive endogenous RNA (ceRNA) mechanism. However, PTENP1 was limited to be applied in the treatment of PCa for the reason of rapid enzymatic degradation, poor intracellular uptake, and excessively long base sequence to be synthesized. Considering the unique advantages of artificial nanomaterials in drug loading and transport, black phosphorus (BP) nanosheet was employed as a gene-drug carrier in this study. RESULTS: The sequence of PTENP1 was adopted as a template which was randomly divided into four segments with a length of about 1000 nucleotide bases to synthesize four different RNA fragments as gene drugs, and loaded onto polyethyleneimine (PEI)-modified BP nanosheets to construct BP-PEI@RNA delivery platforms. The RNAs could be effectively delivered into PC3 cells by BP-PEI nanosheets and elevating PTEN expression by competitive binding microRNAs (miRNAs) which target PTEN mRNA, ultimately exerting anti-tumor effects. CONCLUSIONS: Therefore, this study demonstrated that BP-PEI@RNAs is a promising gene therapeutic platform for PCa treatment.


Assuntos
Nanoestruturas , PTEN Fosfo-Hidrolase , Fósforo , Neoplasias da Próstata , Masculino , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Humanos , Neoplasias da Próstata/genética , Neoplasias da Próstata/terapia , Fósforo/química , Nanoestruturas/química , MicroRNAs/genética , Linhagem Celular Tumoral , Células PC-3 , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Polietilenoimina/química , Animais , Técnicas de Transferência de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , RNA Endógeno Competitivo
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