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1.
Adv Healthc Mater ; : e2400664, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39039988

RESUMO

The development of narrow-spectrum antimicrobial agents is paramount for swiftly eradicating pathogenic bacteria, mitigating the onset of drug resistance, and preserving the homeostasis of bacterial microbiota in tissues. Owing to the limited affinity between the hydrophobic lipid bilayer interior of bacterial cells and most hydrophilic, polar peptides, the construction of a distinctive class of four-armed host-defense peptides/peptidomimetics (HDPs) is proposed with enhanced specificity and membrane perturbation capability against Pseudomonas aeruginosa by incorporating imidazole groups. These groups demonstrate substantial affinity for unsaturated phospholipids, which are predominantly expressed in the cell membrane of P. aeruginosa, thereby enabling HDPs to exhibit narrow-spectrum activity against this bacterium. Computational simulations and experimental investigations have corroborated that the imidazole-rich, four-armed peptidomimetics exhibit notable selectivity toward bacteria over mammalian cells. Among them, 4H10, characterized by its abundant and densely distributed imidazole groups, exhibits impressive activity against various clinically isolated P. aeruginosa strains. Moreover, 4H10 has demonstrated potential as an antibiotic adjuvant, enhancing doxycycline accumulation and exerting effects on intracellular targets by efficiently disrupting bacterial cell membranes. Consequently, the hydrogel composed of 4H10 and doxycycline emerged as a promising topical agent, significantly diminishing the skin P. aeruginosa burden by 97.1% within 2 days while inducing minimal local and systemic toxicity.

2.
Nat Biotechnol ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653798

RESUMO

T cell receptor (TCR) gene therapy is a potent form of cellular immunotherapy in which patient T cells are genetically engineered to express TCRs with defined tumor reactivity. However, the isolation of therapeutic TCRs is complicated by both the general scarcity of tumor-specific T cells among patient T cell repertoires and the patient-specific nature of T cell epitopes expressed on tumors. Here we describe a high-throughput, personalized TCR discovery pipeline that enables the assembly of complex synthetic TCR libraries in a one-pot reaction, followed by pooled expression in reporter T cells and functional genetic screening against patient-derived tumor or antigen-presenting cells. We applied the method to screen thousands of tumor-infiltrating lymphocyte (TIL)-derived TCRs from multiple patients and identified dozens of CD4+ and CD8+ T-cell-derived TCRs with potent tumor reactivity, including TCRs that recognized patient-specific neoantigens.

4.
EMBO Rep ; 24(12): e57828, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37971847

RESUMO

Microbial products, such as lipopolysaccharide (LPS), can elicit efficient innate immune responses against invading pathogens. However, priming with LPS can induce a form of innate immune memory, termed innate immune "tolerance", which blunts subsequent NF-κB signaling. Although epigenetic and transcriptional reprogramming has been shown to play a role in innate immune memory, the involvement of post-translational regulation remains unclear. Here, we report that ubiquitin-specific protease 3 (USP3) participates in establishing "tolerance" innate immune memory through non-transcriptional feedback. Upon NF-κB signaling activation, USP3 is stabilized and exits the nucleus. The cytoplasmic USP3 specifically removes the K63-linked polyubiquitin chains on MyD88, thus negatively regulating TLR/IL1ß-induced inflammatory signaling activation. Importantly, cytoplasmic translocation is a prerequisite step for USP3 to deubiquitinate MyD88. Additionally, LPS priming could induce cytoplasmic retention and faster and stronger cytoplasmic translocation of USP3, enabling it to quickly shut down NF-κB signaling upon the second LPS challenge. This work identifies a previously unrecognized post-translational feedback loop in the MyD88-USP3 axis, which is critical for inducing normal "tolerance" innate immune memory.


Assuntos
Fator 88 de Diferenciação Mieloide , NF-kappa B , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Lipopolissacarídeos/farmacologia , Transdução de Sinais , Imunidade Inata , Tolerância Imunológica
5.
Hepatol Commun ; 5(6): 1106-1119, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34141993

RESUMO

Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) remains a global health concern, and HBV proteins may be ideal targets for T cell-based immunotherapy for HCC. There is a need for fast and efficient identification of HBV-specific T cell receptors (TCRs) for the development of TCR-transduced T (TCR-T) cell-based immunotherapy. Two widely employed TCR identification approaches, T cell clonal expansion and single-cell sequencing, involve a TCR singularization process for the direct identification of Vα and Vß pairs of TCR chains. Clonal expansion of T cells is well known to have tedious time and effort requirements due to the use of T cell cultures, whereas single-cell sequencing is limited by the requirements of cell sorting and the preparation of a single-cell immune-transcriptome library as well as the massive cost of the whole procedure. Here, we present a next-generation sequencing (NGS)-based HBV-specific TCR identification that does not require the TCR singularization process. Conclusion: Two pairing strategies, ranking-based strategy and α-ß chain mixture-based strategy, have proved to be useful for NGS-based TCR identification, particularly for polyclonal T cells purified by a peptide-major histocompatibility complex (pMHC) multimer-based approach. Functional evaluation confirmed the specificity and avidity of two identified HBV-specific TCRs, which may potentially be used to produce TCR-T cells to treat patients with HBV-related HCC.

6.
Autophagy ; 17(6): 1367-1378, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32453962

RESUMO

Macroautophagy/autophagy, a eukaryotic homeostatic process that sequesters cytoplasmic constituents for lysosomal degradation, is orchestrated by a number of autophagy-related (ATG) proteins tightly controlled by post-translational modifications. However, the involvement of reversible ubiquitination in the regulation of autophagy remains largely unclear. Here, we performed a single-guide RNA-based screening assay to investigate the functions of deubiquitinating enzymes (DUBs) in regulating autophagy. We identified previously unrecognized roles of several DUBs in modulating autophagy at multiple levels by targeting various ATG proteins. Mechanistically, we demonstrated that STAMBP/AMSH (STAM-binding protein) promotes the stabilization of ULK1 by removing its lysine 48 (K48)-linked ubiquitination, whereas OTUD7B mediates the degradation of PIK3 C3 by enhancing its K48-linked ubiquitination, thus positively or negatively affects autophagy flux, respectively. Together, our study elaborated on the broad involvement of DUBs in regulating autophagy and uncovered the critical roles of the reversible ubiquitination in the modification of ATG proteins.Abbreviations: ATG: autophagy-related; Baf A1: bafilomycin A1; DUB: deubiquitinating enzyme; EBSS: Earle's balanced salt solution; KO: knockout; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; OTUD7B: OTU domain-containing protein 7B; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; sgRNA: single-guide RNA; SQSTM1/p62: sequestosome 1; STAMBP/AMSH: STAM-binding protein; ULK1: unc-51 like autophagy activating kinase 1; USP: ubiquitin specific peptidase.


Assuntos
Autofagia/fisiologia , Ensaios de Triagem em Larga Escala , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação/fisiologia , Endopeptidases/metabolismo , Ensaios de Triagem em Larga Escala/métodos , Humanos , Lisossomos/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia
7.
Bioorg Chem ; 100: 103904, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32413630

RESUMO

Phototriggered drug delivery systems (PTDDSs) facilitate controlled delivery of drugs loaded on photoactive platform to the target region under light stimulation. The present study investigated the synthesis and efficacy of carbazole-coumarin (CC)-fused heterocycles as a PTDDS platform for the photocontrolled release of a chemotherapeutic agent, chlorambucil, in an in vitro model of human breast and leukemia cancer cells. CC-fused heterocycles were constructed using 4-hydroxycarbazole as the starting material, and further modification of these heterocycles yielded two CC derivatives. CC-7 with an additional - COOH group and CC-8 with the triphenylphosphonium (TPP) group, a mitochondria-targeting ligand introduced in the carbazole ring, dissolved in polar solvents and exhibited emission bands at 360 and 450 nm, respectively. The results indicate that visible light of 405 nm triggers the photolysis of the CC-drug conjugate and efficiently delivers the drug in both in vitro cancer cell models. Cytotoxicity evaluation indicates the suppression of proliferation of both types of cells treated with CC-8 under synergy effect combining drug potency and photosensitization. Further, the lower IC50 of CC-8 toward leukemia cells suggests the efficacy of the TPP ligand in increasing the bioavailability of CC-drug conjugates in leukemia treatment. Studies on mitochondria-targeting drug delivery systems are required for improving the performance of anticancer drugs.


Assuntos
Antineoplásicos/administração & dosagem , Carbazóis/química , Clorambucila/administração & dosagem , Cumarínicos/química , Preparações de Ação Retardada/química , Leucemia/tratamento farmacológico , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Clorambucila/farmacocinética , Clorambucila/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Luz
8.
Immunopharmacol Immunotoxicol ; 42(4): 319-329, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32419542

RESUMO

AIM: Adoptive cell therapy (ACT) of tumor-infiltrating lymphocytes (TILs) has demonstrated clinical benefits in metastatic melanoma treatment. However, the clinical application of TILs produced by a widely used standard protocol from non-small cell lung cancer (NSCLC) can be quite challenging because of the limited clinical benefits. A comprehensive phenotypic knowledge of TILs obtained from NSCLC is important for the development and improvement of personalized TIL therapy for NSCLC patients. METHODS: In this study, we successfully expanded TILs from 141 NSCLC tissues which can be used in clinical ACT after expansion by a rapid expansion protocol (REP). RESULTS: Our study indicates that the clinicopathological characteristics of patients have considerable impacts on the phenotype of in vitro TIL culture products. Different culture conditions are necessary for patients with different clinical features. Specific manipulations before REP expansion are required depending on the different phenotypes of TIL cultures (e.g. depletion of immune-suppressive γδT cells). With these optimizations, next-generation TIL therapy may become a treatment alternative for NSCLC patients in the future.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Imunoterapia Adotiva/métodos , Neoplasias Pulmonares/imunologia , Linfócitos do Interstício Tumoral/imunologia , Fenótipo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Linfócitos do Interstício Tumoral/patologia , Masculino , Pessoa de Meia-Idade , Células Tumorais Cultivadas
9.
Sensors (Basel) ; 20(10)2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32438608

RESUMO

Milling is a main processing mode of the modern manufacturing industry, which seriously affects the quality and precision of the machined workpiece. However, it is difficult to monitor the tool wear condition in the continuous cutting process, especially under a variable speed condition. The existing tool wear condition monitoring methods only carry out analysis with a constant engine speed. Different from the general monitoring methods, this paper put forward a milling cutter wear condition monitoring method based on order analysis (OA) and stacked sparse autoencoder (SSAE). The methodology in the research include signals feature extraction and tool wear state monitoring and were designed to analyze the three-phase spindle current signals instead of the traditional force signals and vibration signals. The variable speed signals were transformed into angle domain stationary signals by order analysis, and the SSAE neural network was used to monitor the tool wear state. The proposed method was verified on the laboratory signals and the results showed a better performance than the other methods and a better applicability in actual industrial manufacturing.

10.
Sensors (Basel) ; 20(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230874

RESUMO

Prognostics and health management technology (PHM), a measure to ensure the reliability and safety of the operation of industrial machinery, has attracted attention and application adequately. However, how to use the monitored information to evaluate the degradation of rolling bearings is a significant issue for its predictive maintenance and autonomic logistics. This work presents a reliable health prognosis approach to estimate the health indicator (HI) and remaining useful life (RUL) of rolling bearings. Firstly, to accurately capture the degradation process, a novel health index (HI) is constructed based on correlation kurtosis for different iteration periods and a Gaussian process latency variable model (GPLVM). Then, a multiple convolutional long short-term memory (MCLSTM) network is proposed to predict HI values and RUL values. Finally, we perform experimental datasets of rolling bearings, demonstrating that the presented method surpasses other state-of-the-art prognosis approaches. The results also confirm the feasibility of the presented method in industrial machinery.

11.
Exp Cell Res ; 383(1): 111497, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31301291

RESUMO

TGF-ß-activated kinase 1 (TAK1) plays a pivotal role in Toll-like receptor (TLR) signaling pathway. However, the mechanisms controlling its activity remain poorly understood. Here, we show that leucine-rich repeat containing 62 (LRRC62), a previously uncharacterized protein, negatively regulates TLR signaling by targeting TAK1. Expression of LRRC62 inhibits the TLRs-induced production of pro-inflammatory cytokine, whereas deficiency in LRRC62 enhances the activation of NF-κB and MAPK signaling and increases the production of pro-inflammatory cytokines. Mechanically, LRRC62 functions as an adaptor to recruit deubiquitinase CYLD to TAK1, thus inhibits the K63-linked poly-ubiquitination and activation of TAK1. Together, our findings uncover an unrecognized mechanism by which LRRC62 antagonizes the activation of TAK1 in a CYLD-mediated deubiquitination-dependent manner, thereby balancing Toll-like receptor signaling to avert overzealous inflammation.


Assuntos
Enzima Desubiquitinante CYLD/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Receptores Toll-Like/metabolismo , Ubiquitinação , Enzima Desubiquitinante CYLD/genética , Células HEK293 , Humanos , MAP Quinase Quinase Quinases/genética , Proteínas de Membrana/genética , NF-kappa B/genética , Ligação Proteica , Proteólise , Transdução de Sinais , Receptores Toll-Like/genética
12.
Colloids Surf B Biointerfaces ; 175: 428-435, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30562717

RESUMO

In this article, we demonstrate the self-assembly and photoresponive behavior of a novel coumarin-based amphiphilic dendron in both aqueous solution and air-water interface. The dendritic structure, namely C-IG1, was composed of a lipophilic cholesterol and hydrophilic poly(amido amine) (PAMAM) dendron, and the amphiphilic counterpart is interconnected by a photolabile coumarin carbonate ester, enabling the photoinduced degradation of the amphiphiles in protic solvents via SN1-like mechanism. A Nile red solubilization fluorescence assay suggests a low critical aggregation concentration for the micelle formation of C-IG1 in aqueous solutions (3.9 × 10-5 M); the Langmuir analysis further indicates that C-IG1 possesses significant compressibility in air-water interface, eventually forming homogeneous monolayers with a final molecular area (A0) of 36 Å2. Notably, the micelles and Langmuir monolayer are quite stable until photo-triggered dissociation based on the photocleavage of C-IG1 amphiphile activated by 365-nm incident light. Moreover, the transition in interfacial morphology of the Langmuir monolayer during the assembly and photodegradation processes also can be visually analyzed by incorporating Nile red probes with in situ monitoring through fluorescence microscopy. The thin film deposited on a glass substrate by the Langmuir-Blodgett technique also shows a photoresponsive behavior based on the change in the contact angles of a water droplet on the surface upon light stimulation. The binding affinity of C-IG1 and cyclic DNA determined by the fluorescence quenching analysis of the coumarin reporter suggests a ground-state macromolecular complexation process occurring through polyvalent interactions between the pseudodendrimers and biomacromolecules. The ethidium bromide displacement assay further indicates thus dendriplex formation at low nitrogen-to-phosphorous value (N/P < 1) and confirms that the decomplexation accompanied by DNA release can be achieved through an active phototriggered route under spatiotemporal control.


Assuntos
Ar , Cumarínicos/química , DNA/metabolismo , Dendrímeros/química , Fotólise , Água , DNA/química , Fluorescência , Interações Hidrofóbicas e Hidrofílicas , Micelas , Propriedades de Superfície
13.
Nat Commun ; 8(1): 1977, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-29215004

RESUMO

The adaptor protein TRAF6 has a central function in Toll-like receptor (TLR) signalling, yet the molecular mechanisms controlling its activity and stability are unclear. Here we show that NLRP11, a primate specific gene, inhibits TLR signalling by targeting TRAF6 for degradation. NLRP11 recruits the ubiquitin ligase RNF19A to catalyze K48-linked ubiquitination of TRAF6 at multiple sites, thereby leading to the degradation of TRAF6. Furthermore, deficiency in either NLRP11 or RNF19A abrogates K48-linked ubiquitination and degradation of TRAF6, which promotes activation of NF-κB and MAPK signalling and increases the production of proinflammatory cytokines. Therefore, our findings identify NLRP11 as a conserved negative regulator of TLR signalling in primate cells and reveal a mechanism by which the NLRP11-RNF19A axis targets TRAF6 for degradation.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Receptores Toll-Like/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Linfócitos B , Linhagem Celular , Citocinas/metabolismo , Expressão Gênica , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipopolissacarídeos/efeitos adversos , Mutagênese Sítio-Dirigida , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T , Células THP-1 , Fator 2 Associado a Receptor de TNF/metabolismo , Ubiquitinação
14.
Cell Death Dis ; 8(5): e2831, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28542145

RESUMO

Tripartite motif-containing protein 45 (TRIM45) belongs to a large family of RING-finger-containing E3 ligases, which are highly expressed in the brain. However, little is known regarding the role of TRIM45 in cancer biology, especially in human glioma. Here, we report that TRIM45 expression is significantly reduced in glioma tissue samples. Overexpression of TRIM45 suppresses proliferation and tumorigenicity in glioblastoma cells in vitro and in vivo. In addition, CRISPR/Cas9-mediated knockout of TRIM45 promotes proliferation and inhibits apoptosis in glioblastoma cells. Further mechanistic analyses show that TRIM45 interacts with and stabilizes p53. TRIM45 conjugates K63-linked polyubiquitin chain to the C-terminal six lysine residues of p53, thereby inhibiting the availability of these residues to the K48-linked polyubiquitination that targets p53 for degradation. These findings suggest that TRIM45 is a novel tumor suppressor that stabilizes and activates p53 in glioma.


Assuntos
Encéfalo/metabolismo , Lisina/metabolismo , Proteínas Repressoras/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Animais , Apoptose , Biocatálise , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/patologia , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Biológicos , Estabilidade Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Transdução de Sinais
15.
FEBS Lett ; 591(1): 145-154, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27926990

RESUMO

F-box proteins play pivotal roles in multiple cellular processes; however, little is known about their functions in glioma progression. In this study, we found that expression of the F-box and leucine-rich repeat protein 18 (FBXL18) is significantly upregulated in glioma tissues. Depletion of FBXL18 in glioma cells suppresses proliferation and anchorage-independent cell growth, and promotes apoptosis. We also demonstrate that depletion of FBXL18 significantly inhibits Akt activity and the phosphorylation of FOXO3a, which leads to upregulation of BCL2L11. Further mechanistic analyses indicate that FBXL18 promotes the K63-linked ubiquitination of Akt, which is required for its activation. Taken together, our results suggest that FBXL18 plays an oncogenic role through promoting K63-linked ubiquitination of Akt in glioma.


Assuntos
Progressão da Doença , Proteínas F-Box/metabolismo , Glioma/metabolismo , Glioma/patologia , Lisina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ubiquitinação , Apoptose , Proteína 11 Semelhante a Bcl-2/genética , Proteína 11 Semelhante a Bcl-2/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Regulação para Cima/genética
16.
Exp Cell Res ; 347(1): 65-73, 2016 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-27426725

RESUMO

Activation of NF-κB signaling plays pivotal roles in innate immune responses against pathogens. It requires strict control to avert inflammatory diseases. However, the mechanisms underlying this tight regulation are not completely understood. Here, we identified LRRC14, a novel member of LRR (leucine-rich repeat) protein family, as a negative regulator in TLR signaling. Expression of LRRC14 resulted in decreased activation of NF-κB, whereas knockdown of LRRC14 enhanced NF-κB activation as well as the production of inflammatory cytokines. Mechanistically, LRRC14 bound to HLH domain of IKKß to block its interaction with NEMO and thereby inhibiting the phosphorylation of IKKß and NF-κB activation. In addition, our data showed that TLR signaling led to lower expression of LRRC14. Together, LRRC14 may function as a checkpoint to prevent overzealous inflammation.


Assuntos
Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Proteínas/metabolismo , Transdução de Sinais , Receptores Toll-Like/metabolismo , Animais , Linhagem Celular , Humanos , Proteínas de Repetições Ricas em Leucina , Camundongos , Fosforilação , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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