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1.
Nat Immunol ; 15(10): 947-56, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25129370

RESUMO

The transcription factor ThPOK promotes CD4(+) T cell differentiation in the thymus. Here, using a mouse strain that allows post-thymic gene deletion, we show that ThPOK maintains CD4(+) T lineage integrity and couples effector differentiation to environmental cues after antigenic stimulation. ThPOK preserved the integrity and amplitude of effector responses and was required for proper differentiation of types 1 and 2 helper T cells in vivo by restraining the expression and function of Runx3, a nuclear factor crucial for cytotoxic T cell differentiation. The transcription factor LRF acts redundantly with ThPOK to prevent the transdifferentiation of mature CD4(+) T cells into CD8(+) T cells. As such, the ThPOK-LRF transcriptional module was essential for CD4(+) T cell integrity and responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Proteínas de Ligação a DNA/imunologia , Timo/imunologia , Fatores de Transcrição/imunologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular/imunologia , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Subunidade alfa 3 de Fator de Ligação ao Core/imunologia , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Timo/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/imunologia
2.
Nature ; 581(7808): 329-332, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433610

RESUMO

Diacylglycerol O-acyltransferase 1 (DGAT1) synthesizes triacylglycerides and is required for dietary fat absorption and fat storage in humans1. DGAT1 belongs to the membrane-bound O-acyltransferase (MBOAT) superfamily, members of which are found in all kingdoms of life and are involved in the acylation of lipids and proteins2,3. How human DGAT1 and other mammalian members of the MBOAT family recognize their substrates and catalyse their reactions is unknown. The absence of three-dimensional structures also hampers rational targeting of DGAT1 for therapeutic purposes. Here we present the cryo-electron microscopy structure of human DGAT1 in complex with an oleoyl-CoA substrate. Each DGAT1 protomer has nine transmembrane helices, eight of which form a conserved structural fold that we name the MBOAT fold. The MBOAT fold in DGAT1 forms a hollow chamber in the membrane that encloses highly conserved catalytic residues. The chamber has separate entrances for each of the two substrates, fatty acyl-CoA and diacylglycerol. DGAT1 can exist as either a homodimer or a homotetramer and the two forms have similar enzymatic activity. The N terminus of DGAT1 interacts with the neighbouring protomer and these interactions are required for enzymatic activity.


Assuntos
Microscopia Crioeletrônica , Diacilglicerol O-Aciltransferase/química , Diacilglicerol O-Aciltransferase/metabolismo , Acil Coenzima A/química , Acil Coenzima A/metabolismo , Sítios de Ligação , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/ultraestrutura , Diglicerídeos/metabolismo , Humanos , Modelos Moleculares , Multimerização Proteica , Relação Estrutura-Atividade , Triglicerídeos/metabolismo
3.
Nucleic Acids Res ; 51(2): 501-516, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35929025

RESUMO

Individual cells are basic units of life. Despite extensive efforts to characterize the cellular heterogeneity of different organisms, cross-species comparisons of landscape dynamics have not been achieved. Here, we applied single-cell RNA sequencing (scRNA-seq) to map organism-level cell landscapes at multiple life stages for mice, zebrafish and Drosophila. By integrating the comprehensive dataset of > 2.6 million single cells, we constructed a cross-species cell landscape and identified signatures and common pathways that changed throughout the life span. We identified structural inflammation and mitochondrial dysfunction as the most common hallmarks of organism aging, and found that pharmacological activation of mitochondrial metabolism alleviated aging phenotypes in mice. The cross-species cell landscape with other published datasets were stored in an integrated online portal-Cell Landscape. Our work provides a valuable resource for studying lineage development, maturation and aging.


How many cell types are there in nature? How do they change during the life cycle? These are two fundamental questions that researchers have been trying to understand in the area of biology. In this study, single-cell mRNA sequencing data were used to profile over 2.6 million individual cells from mice, zebrafish and Drosophila at different life stages, 1.3 million of which were newly collected. The comprehensive datasets allow investigators to construct a cross-species cell landscape that helps to reveal the conservation and diversity of cell taxonomies at genetic and regulatory levels. The resources in this study are assembled into a publicly available website at http://bis.zju.edu.cn/cellatlas/.


Assuntos
Análise de Célula Única , Animais , Camundongos , Análise de Sequência de RNA , Peixe-Zebra/crescimento & desenvolvimento , Drosophila/crescimento & desenvolvimento
4.
Gastroenterology ; 165(1): 88-103, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36921674

RESUMO

BACKGROUND & AIMS: Gastric cancer (GC) is a major cancer type characterized by high heterogeneity in both tumor cells and the tumor immune microenvironment (TIME). One intractable GC subtype is gastric signet-ring cell carcinoma (GSRCC), which is associated with poor prognosis. However, it remains unclear what the GSRCC TIME characteristics are and how these characteristics may contribute to clinical outcomes. METHODS: We enrolled 32 patients with advanced GC of diverse subtypes and profiled their TIME using an immune-targeted single-cell profiling strategy, including (1) immune-targeted single-cell RNA sequencing (n = 20 patients) and (2) protein expression profiling by a targeted antibody panel for mass cytometry (n = 12 patients). We also generated matched V(D)J (variable, diversity, and joining gene segments) sequencing of T and B cells along CD45+ immunocytes. RESULTS: We found that compared to non-GSRCC, the GSRCC TIME appears to be quiescent, where both CD4+ and CD8+ T cells are difficult to be mobilized, which further impairs the proper functions of B cells. CXCL13, mainly produced by follicular helper T cells, T helper type 17, and exhausted CD8+ T cells, is a central coordinator of this transformation. We show that CXCL13 expression can predict the response to immune checkpoint blockade in GC patients, which may be related to its effects on tertiary lymphoid structures. CONCLUSIONS: Our study provides a comprehensive molecular portrait of immune cell compositions and cell states in advanced GC patients, highlighting adaptive immune irresponsiveness in GSRCC and a mediator role of CXCL13 in TIME. Our targeted single-cell transcriptomic and proteomic profiling represents a powerful approach for TIME-oriented translational research.


Assuntos
Carcinoma de Células em Anel de Sinete , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Linfócitos T CD8-Positivos , Proteômica , Carcinoma de Células em Anel de Sinete/genética , Microambiente Tumoral
5.
Anal Chem ; 96(42): 16768-16776, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39394983

RESUMO

Native mass spectrometry (MS) reveals the role of specific lipids in modulating membrane protein structure and function. Membrane proteins solubilized in detergents are often introduced into the mass spectrometer. However, detergents commonly used for structural studies, such as dodecylmaltoside, tend to generate highly charged ions, leading to protein unfolding, thereby diminishing their utility in characterizing protein-lipid interactions. Thus, there is a critical need to develop approaches to investigate protein-lipid interactions in different detergents. Here, we demonstrate how charge-reducing molecules, such as spermine and trimethylamine-N-oxide, enable the opportunity to characterize lipid binding to the bacterial water channel (AqpZ) and ammonia channel (AmtB) in complex with regulatory protein GlnK in different detergent environments. We find that protein-lipid interactions not only are protein-dependent but also can be influenced by the detergent and type of charge-reducing molecule. AqpZ-lipid interactions are enhanced in LDAO (n-dodecyl-N,N-dimethylamine-N-oxide), whereas the interaction of AmtB-GlnK with lipids is comparable among different detergents. A fluorescent lipid binding assay also shows detergent dependence for AqpZ-lipid interactions, consistent with results from native MS. Taken together, native MS will play a pivotal role in establishing optimal experimental parameters that will be invaluable for various applications, such as drug discovery as well as biochemical and structural investigations.


Assuntos
Detergentes , Proteínas de Escherichia coli , Espectrometria de Massas , Detergentes/química , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Aquaporinas/química , Aquaporinas/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/química , Metilaminas/química , Dimetilaminas/química , Proteínas de Transporte de Cátions
6.
Immunol Cell Biol ; 102(6): 425-428, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38650445

RESUMO

Unraveling the complexities of T cell aging is essential for developing targeted interventions to enhance immune function in the elderly. This article for the Highlights of 2023 Series integrates recent findings published in 2023, offering a panoramic view of the current understanding of T cell aging and its implications.


Assuntos
Senescência Celular , Linfócitos T , Humanos , Linfócitos T/imunologia , Senescência Celular/imunologia , Animais , Envelhecimento/imunologia , Senescência de Células T
7.
Nat Immunol ; 13(6): 560-8, 2012 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-22561606

RESUMO

Signaling via the T cell antigen receptor (TCR) during the CD4(+)CD8(+) double-positive developmental stage determines thymocyte selection and lineage commitment. Here we describe a previously uncharacterized T cell-expressed protein, Tespa1, with critical functions during the positive selection of thymocytes. Tespa1(-/-) mice had fewer mature thymic CD4(+) and CD8(+) T cells, which reflected impaired thymocyte development. Tespa1 associated with the TCR signaling components PLC-γ1 and Grb2, and Tespa1 deficiency resulted in attenuated TCR signaling, as reflected by defective activation of the Erk-AP-1 and Ca(2+)-NFAT pathways. Our findings demonstrate that Tespa1 is a component of the TCR signalosome and is essential for T cell selection and maturation through the regulation of TCR signaling during T cell development.


Assuntos
Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Timo/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular/imunologia , Clonagem Molecular , Proteína Adaptadora GRB2/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Fosfolipase C gama/imunologia , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Transdução de Sinais/imunologia , Timo/citologia
8.
BMC Cancer ; 24(1): 398, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553681

RESUMO

BACKGROUND: Cancer-related fatigue (CRF) is considered one of the most prevalent and distressing symptoms among cancer patients and may vary among patients with different cancer types. However, few studies have explored the influence of physical and psychological symptoms on CRF among esophageal cancer (EC) patients without esophagectomy. Therefore, this study aimed to examine the effects of physical and psychological symptoms on CRF among EC patients without esophagectomy. METHODS: In the present study, a cross-sectional study was conducted from February 2021 to March 2022 in Liaoning Province, China. Among the 112 included participants, 97 completed our investigation. The questionnaires used consisted of the Brief Fatigue Inventory (BFI), the MD Anderson Symptom Inventory Gastrointestinal Cancer Module (MDASI-GI), the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7), and demographic and clinical information. Multivariate linear regression was conducted to test the relationships between physical and psychological symptoms and CRF. RESULTS: Of the 97 EC patients, 60.8% reported CRF (BFI ≥ 4). The mean age of the participants was 64.92 years (SD = 8.67). According to the regression model, all the variables explained 74.5% of the variance in CRF. Regression analysis indicated that physical symptoms, including constipation, diarrhoea, and difficulty swallowing, contributed to CRF. On the other hand, depressive symptoms increased the level of CRF among EC patients without esophagectomy. CONCLUSIONS: Given the high prevalence of CRF among EC patients without esophagectomy, it is urgent to emphasize the importance of fatigue management interventions based on physical and psychological symptoms to alleviate CRF in EC patients.


Assuntos
Neoplasias Esofágicas , Neoplasias , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Transversais , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/epidemiologia , Inquéritos e Questionários , Análise de Regressão , Fadiga/epidemiologia , Fadiga/etiologia , Fadiga/diagnóstico , Qualidade de Vida
9.
J Immunol ; 209(5): 916-925, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35922064

RESUMO

Thymocytes need to proliferate into a significant cell mass to allow a subsequent selection process during the double-positive (DP) stage. However, it is not clear at what stage this massive cell proliferation occurs. Immature CD8 single-positive (ISP) cells are a well-defined thymocyte subpopulation. However, the function of this cell subset has not yet been characterized. In this study, we analyzed the transcription pattern of mouse ISP cells and observed higher expression levels of cell cycling genes. We also found out that ISP cells exhibited the highest cell proliferative capacity among thymocytes in different developmental stages. Nuclear protein ataxia-telangiectasia (NPAT/p220) is one of the highly expressed cell cycling genes in ISP cells, which is known to play a critical role in coordinating histone gene expression necessary for rapid cell proliferation. Selective deletion of NPAT at the ISP stage led to reduced thymus size and significant loss of DP cells, secondary to reduced histone gene expression and impaired ISP cell proliferation capacity. A block of thymocyte development at the ISP stage was also observed, which was due to increased IL-7R expression. Continuous IL-7R signal served as a compensating mechanism for cell proliferation upon NPAT deletion, but in turn inhibited the expression of transcription factors TCF-1 and LEF-1, which is essential for the transition of ISP to DP cells. In summary, our study revealed the proliferation capacity of the ISP subpopulation during thymocyte differentiation as well as a vital role of NPAT in this developmental stage.


Assuntos
Histonas , Timócitos , Animais , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Ciclo Celular , Diferenciação Celular , Proliferação de Células , Histonas/metabolismo , Camundongos , Proteínas Nucleares/metabolismo , Timócitos/metabolismo , Timo/metabolismo
10.
J Appl Microbiol ; 135(10)2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39366754

RESUMO

AIMS: To explore the therapeutic potential of Forsythoside B in treating Streptococcus pneumoniae (S. pneumoniae) infections, focusing on its ability to inhibit pneumolysin activity and protect cells from damage. METHODS AND RESULTS: Hemolysis tests were used to evaluate Forsythoside B's inhibitory effect on pneumolysin activity, while growth curve analysis assessed its impact on S. pneumoniae growth. Western blotting and oligomerization analysis were conducted to examine its influence on pneumolysin oligomerization. Cytotoxicity assays, including LDH release and live/dead cell staining, evaluated the protective effects of Forsythoside B against pneumolysin-induced damage in A549 cells. Additionally, a mouse model was employed to test the effects on survival rates, lung bacterial load, and inflammation. The results showed that Forsythoside B significantly inhibited pneumolysin activity, reduced its oligomerization, and protected A549 cells from damage without affecting bacterial growth. In the mouse model, it improved survival rates and reduced lung inflammation, indicating its potential as a therapeutic agent against S. pneumoniae infections. CONCLUSIONS: Forsythoside B shows potential as a therapeutic agent for treating pneumonia, particularly in infections caused by S. pneumoniae.


Assuntos
Proteínas de Bactérias , Streptococcus pneumoniae , Estreptolisinas , Streptococcus pneumoniae/efeitos dos fármacos , Animais , Proteínas de Bactérias/metabolismo , Camundongos , Humanos , Células A549 , Virulência/efeitos dos fármacos , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/microbiologia , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia , Modelos Animais de Doenças , Ácidos Cafeicos , Glucosídeos
11.
J Asthma ; 61(7): 725-735, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38647486

RESUMO

Objective: This study aims to explore the effect of YiQi GuBen capsule on improving mitochondrial dysfunction in an animal model of asthma.Methods: The mice (n = 8) were divided into four groups including control (NC), ovalbumin (OVA), dexamethasone (OVA + DEX), and YiQi GuBen (OVA + YQGB) groups. Firstly, we established an OVA-induced mouse asthma model except for the NC group, which then were treated with dexamethasone and YiQi GuBen capsule. Subsequently, HE staining and Masson staining were used for pathological analysis of mice lung tissues. Next, we used transmission electron microscopy (TEM) to observe the effect of the Yiqi Guben capsule on the ultrastructure of mitochondria. Flow cytometry was used to analyze the ROS level, membrane potential, and the number of mitochondria in lung tissue. Moreover, we analyzed the copy number of mitochondrial DNA (mtDNA) and the expression levels of activator peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and mitochondrial transcription factor A (TFAM).Results: The results of the pathological analysis showed that after treatment with the YiQi GuBen capsule, the lung tissue damage was significantly reduced. In addition, we observed that the ultrastructural damage of mitochondria was improved. Flow cytometry proved that after treatment with the YiQi GuBen capsule, the level of ROS in the mitochondria was effectively reduced, while the mitochondrial membrane potential decreased and the number increased significantly. Moreover, we found that the copy number of mtDNA was significantly increased and the expression levels of PGC-1α and TFAM were significantly upgraded.Conclusion: This study suggests YiQi GuBen capsule can effectively improve mitochondrial dysfunction in the OVA-induced mouse model.


Assuntos
Asma , DNA Mitocondrial , Medicamentos de Ervas Chinesas , Pulmão , Mitocôndrias , Ovalbumina , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Espécies Reativas de Oxigênio , Animais , Asma/tratamento farmacológico , Asma/patologia , Medicamentos de Ervas Chinesas/farmacologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Pulmão/efeitos dos fármacos , Pulmão/patologia , Espécies Reativas de Oxigênio/metabolismo , DNA Mitocondrial/efeitos dos fármacos , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Feminino , Dexametasona/farmacologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Cápsulas , Proteínas de Grupo de Alta Mobilidade
12.
Nucleic Acids Res ; 50(D1): D1244-D1254, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34606616

RESUMO

T-cell receptors (TCRs) and B-cell receptors (BCRs) are critical in recognizing antigens and activating the adaptive immune response. Stochastic V(D)J recombination generates massive TCR/BCR repertoire diversity. Single-cell immune profiling with transcriptome analysis allows the high-throughput study of individual TCR/BCR clonotypes and functions under both normal and pathological settings. However, a comprehensive database linking these data is not yet readily available. Here, we present the human Antigen Receptor database (huARdb), a large-scale human single-cell immune profiling database that contains 444 794 high confidence T or B cells (hcT/B cells) with full-length TCR/BCR sequence and transcriptomes from 215 datasets. All datasets were processed in a uniform workflow, including sequence alignment, cell subtype prediction, unsupervised cell clustering, and clonotype definition. We also developed a multi-functional and user-friendly web interface that provides interactive visualization modules for biologists to analyze the transcriptome and TCR/BCR features at the single-cell level. HuARdb is freely available at https://huarc.net/database with functions for data querying, browsing, downloading, and depositing. In conclusion, huARdb is a comprehensive and multi-perspective atlas for human antigen receptors.


Assuntos
Bases de Dados Genéticas , Receptores de Antígenos de Linfócitos B/classificação , Receptores de Antígenos de Linfócitos T/classificação , Software , Linfócitos B , Humanos , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Análise de Célula Única , Transcriptoma/genética , Recombinação V(D)J/genética
13.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 53(1): 64-72, 2024 Jan 19.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38426692

RESUMO

Hepatocellular carcinoma (HCC) is a serious neoplastic disease with increasing incidence and mortality, accounting for 90% of all liver cancers. Hepatitis viruses are the major causative agents in the development of HCC. Hepatitis A virus (HAV) primarily causes acute infections, which is associated with HCC to a certain extent, as shown by clinicopathological studies. Chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections lead to persistent liver inflammation and cirrhosis, disrupt multiple pathways associated with cellular apoptosis and proliferation, and are the most common viral precursors of HCC. Mutations in the HBV X protein (HBx) gene are closely associated with the incidence of HCC, while the expression of HCV core proteins contributes to hepatocellular lipid accumulation, thereby promoting tumorigenesis. In the clinical setting, hepatitis D virus (HDV) frequently co-infects with HBV, increasing the risk of chronic hepatitis. Hepatitis E virus (HEV) usually causes acute infections. However, chronic infections of HEV have been increasing recently, particularly in immuno-compromised patients and organ transplant recipients, which may increase the risk of progression to cirrhosis and the occurrence of HCC. Early detection, effective intervention and vaccination against these viruses may significantly reduce the incidence of liver cancer, while mechanistic insights into the interplay between hepatitis viruses and HCC may facilitate the development of more effective intervention strategies. This article provides a comprehensive overview of hepatitis viruses and reviews recent advances in research on aberrant hepatic immune responses and the pathogenesis of HCC due to viral infection.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Hepatite B , Hepatite C , Hepatite Viral Humana , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/genética , Hepatite B Crônica/complicações , Hepatite B/complicações , Hepatite Viral Humana/complicações , Hepatite C/complicações , Cirrose Hepática/complicações
14.
J Autoimmun ; 136: 103028, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37001432

RESUMO

Follicular helper T (Tfh) cells are important for generating humoral immune responses by helping B cells form germinal centers (GCs) and the production of high-affinity antibodies. However, aberrant Tfh cell expansion also contributes to the generation of self-reactive autoantibodies and promotes autoantibody-mediated autoimmune diseases such as systemic lupus erythematosus (SLE). Protein phosphatase 2A catalytic subunit alpha isoform (PP2A Cα) expression levels are elevated in peripheral T cells of SLE patients and positively correlate with autoantibody titers and disease activity. Here, we demonstrate a critical role of PP2A in Tfh differentiation by using T cell restricted PP2A Cα deficient mice. We observed impaired Tfh differentiation and GC response in two different classical Tfh induction models. Mechanistic studies revealed that downregulation of protein translation of the Tfh lineage transcription factor BCL6 in PP2A deficient T cells. Importantly, we found that PP2A deficiency by either gene knockout or chemical inhibition alleviated lupus severity in mice. Lastly, we confirmed a positive correlation between PP2A Cα and BCL6 protein levels in human CD4+ T cells from patients with SLE. In summary, our study revealed a critical role of PP2A in regulating Tfh cells and suggests it is a potential therapeutic target for lupus.


Assuntos
Lúpus Eritematoso Sistêmico , Linfócitos T Auxiliares-Indutores , Humanos , Camundongos , Animais , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Autoanticorpos , Linfócitos B , Diferenciação Celular
15.
Bioorg Chem ; 134: 106451, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36907048

RESUMO

Cytotoxic peptides derived from spider venoms have been considered as promising candidates for anticancer treatment. The novel cell penetrating peptide LVTX-8, which is a 25-residue amphipathic α-helical peptide isolated from spider Lycosa vittata, exhibited potent cytotoxicity and is a potential precursor for further anticancer drug development. Nevertheless, LVTX-8 may be easily degraded by multiple proteases, inducing the proteolytic stability problem and short half-life. In this study, ten LVTX-8-based analogs were rationally designed and the efficient manual synthetic method was established by the DIC/Oxyma based condensation system. The cytotoxicity of synthetic peptides was systematically evaluated against seven cancer cell lines. Seven of the derived peptides exhibited high cytotoxicity towards tested cancer in vitro, which was better than or comparable to that of natural LVTX-8. In particular, both N-acetyl and C-hydrazide modified LVTX-8 (825) and the conjugate methotrexate (MTX)-GFLG-LVTX-8 (827) possessed more durable anticancer efficiency, higher proteolytic stability, as well as lower hemolysis. Finally, we confirmed that LVTX-8 could disrupt the integrity of cell membrane, target the mitochondria and reduce the mitochondrial membrane potential to induce the cell death. Taken together, the structural modifications were conducted on LVTX-8 for the first time and the stability significantly improved derivatives 825 and 827 may provide useful references for the modifications of cytotoxic peptides.


Assuntos
Antineoplásicos , Peptídeos Penetradores de Células , Neoplasias , Venenos de Aranha , Humanos , Venenos de Aranha/farmacologia , Venenos de Aranha/química , Venenos de Aranha/metabolismo , Antineoplásicos/farmacologia , Metotrexato/química , Peptídeos Penetradores de Células/química
16.
BMC Anesthesiol ; 23(1): 327, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784079

RESUMO

BACKGROUND AND OBJECTIVES: Dexmedetomidine (DEX) is widely used in clinical sedation which has little effect on cardiopulmonary inhibition, however the mechanism remains to be elucidated. The basal forebrain (BF) is a key nucleus that controls sleep-wake cycle. The horizontal limbs of diagonal bundle (HDB) is one subregions of the BF. The purpose of this study was to examine whether the possible mechanism of DEX is through the α2 adrenergic receptor of BF (HDB). METHODS: In this study, we investigated the effects of DEX on the BF (HDB) by using whole cell patch clamp recordings. The threshold stimulus intensity, the inter-spike-intervals (ISIs) and the frequency of action potential firing in the BF (HDB) neurons were recorded by application of DEX (2 µM) and co-application of a α2 adrenergic receptor antagonist phentolamine (PHEN) (10 µM). RESULTS: DEX (2 µM) increased the threshold stimulus intensity, inhibited the frequency of action potential firing and enlarged the inter-spike-interval (ISI) in the BF (HDB) neurons. These effects were reversed by co-application of PHEN (10 µM). CONCLUSION: Taken together, our findings revealed DEX decreased the discharge activity of BF (HDB) neuron via α2 adrenergic receptors.


Assuntos
Dexmedetomidina , Camundongos , Animais , Dexmedetomidina/farmacologia , Receptores Adrenérgicos alfa 2 , Transdução de Sinais , Neurônios , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia
17.
Med Mol Morphol ; 56(1): 78-83, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35851413

RESUMO

Juvenile polyposis syndrome (JPS) is a rare autosomal dominant inherited disease characterised by multiple juvenile polyps. Genes with JPS-associated mutations and their correlation with the phenotype are currently unknown. Gastrointestinal endoscopy results of a 31-year-old female patient showed multiple polyps in the digestive tract, and the presence of juvenile polyps was confirmed by pathological examination. During follow-up, the patient underwent total gastrectomy and polypectomy several times. Five members of this family were diagnosed with JPS, of which two died and three survived. Full exon gene sequencing of eight members of this family revealed a SMAD4 (NM-005359.3) c.1035C > A (p.Cys345*) mutation. This mutation leads to premature codon termination, causing protein truncation. SMAD4 is a pathogenic gene associated with JPS. This is the first report of an association between the c.1035C > A mutation and JPS pathogenesis. Detection of JPS-related mutations in family members with a genetic predisposition for JPS is very important for genetic counselling, surgical intervention, long-term monitoring and follow-up, and drug treatment.


Assuntos
Polipose Intestinal , Síndromes Neoplásicas Hereditárias , Feminino , Humanos , Sequenciamento do Exoma , Polipose Intestinal/genética , Síndromes Neoplásicas Hereditárias/genética , Células Germinativas , Proteína Smad4/genética
18.
Cancer Cell Int ; 22(1): 69, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35144613

RESUMO

BACKGROUND: Gastric cancer (GC), the most commonly diagnosed cancer worldwide with poor 5-year survival rate in advanced stages. Although immune-related and survival-related biomarkers, which typically comprise aberrantly expressed long non-coding RNAs (lncRNAs) and genes, have been identified, there are no reports of immune-related lncRNA pair (IRLP) signatures for GC. METHODS: In this study, we acquired lncRNA expression profiles from The Cancer Genome Atlas (TCGA) and used the least absolute shrinkage and selection operator (LASSO) Cox proportional hazards model (iteration = 1000) to develop a IRLP prognostic signature. The area under curve (AUC) was used to assess the prognosis predictive power. The multivariate Cox regression analysis was performed to identify whether this signature was an independent prognostic factor. The immune cell infiltration analysis was performed between the two risk groups. Last, molecular experiments were performed to explore LINC01082 is involved in the development of GC. RESULTS: We acquired lncRNA expression profiles and used the LASSO Cox model to develop an 18-IRLP signature with a strong prognostic predictive power. The 5-year AUC values of the training, validation, and overall TCGA datasets were 0.77, 0.86, and 0.80, respectively. The different prognostic outcomes between the high- and low-risk groups were determined using our 18-IRLP signature. Moreover, our 18-IRLP signature was an independent prognostic factor as per the multivariate Cox regression analysis, and showed better prognostic evaluation than the traditional TNM staging system as well as other clinical features. We also found differences in cancer-associated fibroblast and macrophage M2 infiltration and the expression of PD-L1, CTLA4, LAG3, and HLA were also observed between the two risk groups (P < 0.05). Analysis of biological functions revealed that target genes of the lncRNAs in the IRLP signature were enriched in focal adhesion and regulation of actin cytoskeleton. Finally, as one of significant candidates of IRLP signature, overexpression of LINC01082 suppressed the invasion ability of GC cells as well as PD-L1 expression profiles. CONCLUSIONS: Our novel 18-IRLP signature provides new insights regarding immunological biomarkers, imparts a better understanding of the tumor immune microenvironment, and can be used for predicting prognosis and evaluating immune response in GC.

19.
J Immunol ; 204(12): 3248-3261, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32358021

RESUMO

Thymocyte differentiation is a highly complex process that is accompanied by epigenetic changes. Ubiquitin-like containing PHD ring finger 1 (UHRF1) is a critical epigenetic modifier involved in various cellular processes. In this study, we demonstrated that it is highly expressed in T cell precursors of the thymus. Further, its deficiency results in significantly reduced thymocyte cellularity and thymus size in mice. Through systematic analysis based on single-cell RNA sequencing, we found that UHRF1 deficiency thwarts αß T cell lineage development, whereas biasing γδ T lineage differentiation dampens the progression of immature single-positive cells. UHRF1 deficiency promotes the IL-17 secreting and RORγt expression in γδ T cell, indicating a Tγδ17 phenotype. Further, the analysis of gene-regulatory networks demonstrated that UHRF1 controls the expression of early growth response 1 (EGR1). UHRF1 interacts with DNA methyltransferase 1 (DNMT1) at the CpG promoter region of Egr1 loci and affects the nearby chromatin modifications of H3K9me3 and H3K4me3. Taken together, our results demonstrate that UHRF1 is a key factor that mediates the epigenetic regulation of EGR1 and, consequently, thymocyte fate decisions.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Epigênese Genética/genética , Timócitos/fisiologia , Ubiquitina-Proteína Ligases/genética , Animais , Diferenciação Celular/genética , Células Cultivadas , DNA (Citosina-5-)-Metiltransferase 1/genética , Regulação da Expressão Gênica/genética , Histonas/genética , Interleucina-17/genética , Linfócitos Intraepiteliais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Regiões Promotoras Genéticas/genética , Timo/fisiologia
20.
BMC Psychiatry ; 22(1): 750, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36451108

RESUMO

BACKGROUND: The present study aimed to identify profiles of social constraints among Chinese breast cancer patients and to explore the variables associated with these patterns. METHODS: The study recruited 133 Chinese breast cancer patients in Liaoning Province, China, between June 2021 and February 2022. The questionnaire package included the Social Constraints Scale (SCS), the Multidimensional Scale of Perceived Social Support (MSPSS), the Fear of Progression Questionnaire-Short Form (FoP-Q-SF), and the Social Impact Scale (SIS). The methods of statistical analysis used included latent profile analysis (LPA) and multinomial logistic regression. RESULTS: Three latent patterns of social constraints were found: class 1-the low social constraints group (51.9%), class 2-the moderate social constraints group (35.3%), and class 3-the high social constraints group (12.8%). Patients with high social support were more likely to report a low level of social constraint, while patients with a greater fear of progression were more likely to report a moderate or high level of social constraints. Significant differences existed among the latent classes identified by reference to social constraint in terms of education. CONCLUSION: These results suggest that breast cancer patients' perceptions of social constraints vary and exhibit individual differences. Health care providers should take into account patients' fear of progression as well as their social support when developing interventions for patients with a high level of social constraints.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Apoio Social , Medo , Povo Asiático , Escolaridade
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