Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 184
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38894685

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis ( M. tb), remains one of the leading causes of fatal infectious diseases worldwide. The only licensed vaccine, Mycobacterium bovis Bacillus Calmette-Guérin (BCG), has variable efficacy against TB in adults. Insufficiency of immune cell function diminishes the protective effects of the BCG vaccine. It is critical to clarify the mechanism underlying the antimycobacterial immune response during BCG vaccination. Macrophage mannose receptor (MR) is important for enhancing the uptake and processing of glycoconjugated antigens from pathogens for presentation to T cells, but the roles of macrophage MR in the BCG-induced immune response against M. tb are not yet clear. Here, we discover that macrophage MR deficiency impairs the antimycobacterial immune response in BCG-vaccinated mice. Mechanistically, macrophage MR triggers JAK-STAT1 signaling, which promotes antigen presentation via upregulated MHC-II and induces IL-12 production by macrophages, contributing to CD4 + T cell activation and IFN-γ production. MR deficiency in macrophages reduces the vaccine efficacy of BCG and increases susceptibility to M. tb H37Ra challenge in mice. Our results suggest that MR is critical for macrophage antigen presentation and the antimycobacterial immune response to BCG vaccination and offer valuable guidance for the preventive strategy of BCG immunization.

2.
J Am Chem Soc ; 145(9): 5467-5473, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36820840

RESUMO

Hundreds of modified bases have been identified and enzymatically modified to transfer RNAs (tRNAs) to regulate RNA function in various organisms. 2-Methylthio-N6-isopentenyladenosine (ms2i6A), a hypermodified base found at tRNA position 37, exists in both prokaryotes and eukaryotes. ms2i6A is traditionally identified by separating and digesting each tRNA from total RNA using RNA mass spectrometry. A transcriptome-wide and single-base resolution method that enables absolute mapping of ms2i6A along with analysis of its distribution in different RNAs is lacking. Here, through chemoselective methylthio group bioconjugation, we introduce a new approach (redox activated chemical tagging sequencing, ReACT-seq) to detect ms2i6A transcriptome-wide at single-base resolution. Using the chemoselectivity between the methylthio group and oxaziridine group, ms2i6A is bio-orthogonally tagged with an azide group without interference of canonical nucleotides, advancing enrichment of methylthio group modified RNAs prior to sequencing. ReACT-seq was demonstrated on nine known tRNAs and proved to be highly accurate, and the reverse transcription stop (RT-stop) character enables ReACT-seq detection at single-base resolution. In addition, ReACT-seq identified that the modification of ms2i6A is conservative and may not exist in other RNAs.


Assuntos
Isopenteniladenosina , Transcriptoma , Isopenteniladenosina/química , RNA de Transferência/genética , RNA de Transferência/química
3.
Mol Biol Rep ; 50(6): 5247-5254, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37138138

RESUMO

BACKGROUND: Our previous study has reported that interleukin-16 (IL-16) genetic polymorphisms are significantly related to chronic hepatitis B (CHB) and hepatitis B virus-related (HBV-related) hepatocellular carcinoma (HCC). As CHB, liver cirrhosis (LC), and HCC are development processes, this study aimed to determine genetic correlation of IL-16 polymorphisms with HBV-related LC in a Chinese population. METHODS: IL-16 gene rs11556218, rs4072111, and rs4778889 polymorphism in 129 patients with HBV-related LC and 168 healthy individuals were genotyped via polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). PCR-RFLP results were verified by DNA sequencing. RESULTS: The allelic and genotypic distributions of IL-16 rs11556218, rs4072111, and rs4778889 polymorphisms in HBV-related LC patients showed no significant difference from those in healthy controls. Furthermore, no relationship was observed between the haplotype distribution and susceptibility to HBV-related LC. CONCLUSIONS: This work provided the first evidence that the IL-16 genetic polymorphisms may not be associated with HBV-related LC risk.


Assuntos
Hepatite B Crônica , Interleucina-16 , Cirrose Hepática , Humanos , Estudos de Casos e Controles , China/epidemiologia , População do Leste Asiático , Predisposição Genética para Doença , Genótipo , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Interleucina-16/genética , Cirrose Hepática/genética , Cirrose Hepática/virologia , Polimorfismo de Nucleotídeo Único
4.
Planta ; 255(5): 98, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35380264

RESUMO

MAIN CONCLUSION: dmp1dmp2dmp3 mutants created by CRISPR/Cas9 could trigger maternal haploids in the allotetraploid model plant Nicotiana tabacum L. Double haploid (DH) technology is becoming increasingly important because it can significantly accelerate the breeding process. Haploid induction plays a fundamental role in the production of DH lines. Haploid induction has been realized and applied in diploid plants using DMP genes. However, it has yet to be elucidated whether haploid induction could be established in polyploid plants. In the current study, three homologues of the DMP genes (NtDMP1, 2, and 3) were identified in the allotetraploid plant Nicotiana tabacum, and the encoded proteins localized in the endoplasmic reticulum. Loss-of-function mutations in all three genes triggered maternal haploids with an induction rate of 1.52-1.75%. Compared with wild-type tobacco, the created haploid inducer exhibited differences in pollen vigor and seed germination rate. Furthermore, to rapidly and easily screen haploids, a visible haploid identification system was established based on a powdery mildew resistance phenotype. Findings from this study lay the foundation for the potential application of haploid inducers in allotetraploid plants such as tobacco.


Assuntos
Nicotiana , Melhoramento Vegetal , Diploide , Haploidia , Mutação/genética , Nicotiana/genética
5.
Cell Microbiol ; 23(3): e13290, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33217152

RESUMO

Tuberculosis (TB), caused by Mycobacterium tuberculosis (M. tb), is the leading infectious cause of mortality worldwide. One of the key reasons for M. tb pathogenesis is the capability of M. tb to evade immune elimination and survive in macrophage, eventually causing chronic infection. However the pathogenicity mechanism of M. tb is not unclear yet, and thus diagnosis and therapy for TB remains a challenge. The genome of M. tb, encodes a unique protein family known as the PGRS family, with largely unexplored functions. Recently, an increasing number of reports have shown that the PE_PGRS proteins play critical roles in bacterial pathogenesis and immune evasion. The PE_PGRS protein family, characterized by a special N-terminal PE (Pro (P)-Glu (E) motif) domain and a C-terminal PGRS (Polymorphic GC-rich Repetitive Sequences) domain, is restricted mainly to pathogenic mycobacteria. Here we summarize current literature on the PE_PGRS as vital proteins in promoting bacterial survival and modulating host immunity, cell death and metabolism. We also highlight the potential of PE_PGRS as novel targets of anti-mycobacterial interventions for TB control.


Assuntos
Antígenos de Bactérias , Proteínas de Bactérias , Proteínas de Membrana , Mycobacterium tuberculosis/fisiologia , Tuberculose/microbiologia , Animais , Apresentação de Antígeno , Antígenos de Bactérias/química , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/metabolismo , Autofagia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Morte Celular , Interações Hospedeiro-Patógeno , Humanos , Evasão da Resposta Imune , Metabolismo dos Lipídeos , Lisossomos/fisiologia , Macrófagos/microbiologia , Macrófagos/fisiologia , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/patogenicidade , Tuberculose/diagnóstico , Tuberculose/imunologia , Tuberculose/prevenção & controle , Vacinas contra a Tuberculose
6.
Chem Biodivers ; 19(2): e202100602, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34927353

RESUMO

Here six novel imidazolinone derivatives have been synthesized and the compound 4b containing 5-para-methoxy-phenylidene and 2-thioalkylation terminal substitution with 3'-cyano-2',6'-dimethylphenyl showed the best anti-HCV activity and the lowest cytotoxicity. Selectivity index (SI=CC50 /IC50 ) for the 4b was determined as 36, indicating that compound 4b was highly selective towards HCV.


Assuntos
Antivirais , Hepacivirus , Antivirais/farmacologia , Relação Estrutura-Atividade
7.
Plant Dis ; 106(12): 3033-3039, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35612580

RESUMO

Mixed virus infection has increasingly become a problem in the production of Solanaceae crops in recent years; therefore, a fast and accurate detection method is needed. In this study, a novel triplex immunostrip assay was developed for the simultaneous detection of tobacco mosaic virus (TMV), tobacco vein banding mosaic virus (TVBMV), and potato virus Y (PVY). The limits of detection of this novel immunostrip reached 200 ppb (ng/ml), 1 ppm (µg/ml), and 2 ppm for TMV, PVY, and TVBMV particles, respectively. Importantly, no cross-reactivity was observed among TMV, TVBMV, and PVY or to a nontarget virus. When the assay was applied to suspected virus-infected tobacco, tomato, and potato samples collected from fields in Southwest China, samples of single or mixed virus infection were successfully identified. In conclusion, the triplex immunostrip assay provides a fast and easy to use on-site detection method for field epidemiological studies of TMV, TVBMV, and PVY, and for managing diseases that are caused by them.


Assuntos
Potyvirus , Vírus do Mosaico do Tabaco , Doenças das Plantas , Nicotiana
8.
J Am Chem Soc ; 143(46): 19317-19329, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34762804

RESUMO

GFP-like fluorescent proteins and their molecular mimics have revolutionized bioimaging research, but their emissions are largely limited in the visible to far-red region, hampering the in vivo applications in intact animals. Herein, we structurally modulate GFP-like chromophores using a donor-acceptor-acceptor (D-A-A') molecular configuration to discover a set of novel fluorogenic derivatives with infrared-shifted spectra. These chromophores can be fluorescently elicited by their specific interaction with G-quadruplex (G4), a unique noncanonical nucleic acid secondary structure, via inhibition of the chromophores' twisted-intramolecular charge transfer. This feature allows us to create, for the first time, FP mimics with tunable emission in the near-infrared (NIR) region (Emmax = 664-705 nm), namely, infrared G-quadruplex mimics of FPs (igMFP). Compared with their FP counterparts, igMFPs exhibit remarkably higher quantum yields, larger Stokes shift, and better photostability. In a proof-of-concept application using pathogen-related G4s as the target, we exploited igMFPs to directly visualize native hepatitis C virus (HCV) RNA genome in living cells via their in situ formation by the chromophore-bound viral G4 structure in the HCV core gene. Furthermore, igMFPs are capable of high contrast HCV RNA imaging in living mice bearing a HCV RNA-presenting mini-organ, providing the first application of FP mimics in whole-animal imaging.


Assuntos
Fluorescência , Corantes Fluorescentes/química , Proteínas Luminescentes/química , Ácidos Nucleicos/química , RNA Viral/análise , Animais , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Hepacivirus/genética , Humanos , Raios Infravermelhos , Proteínas Luminescentes/síntese química , Camundongos , RNA Viral/genética , Espectrometria de Fluorescência
9.
Eur J Immunol ; 50(9): 1350-1361, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32339264

RESUMO

Chronic HCV infection can lead to cirrhosis and is associated with increased mortality. Interleukin (IL)-10-producing B cells (B10 cells) are regulatory cells that suppress cellular immune responses. Here, we aimed to determine whether HCV induces B10 cells and assess the roles of the B10 cells during HCV infection. HCV-induced B10 cells were enriched in CD19hi and CD1dhi CD5+ cell populations. HCV predominantly triggered the TLR2-MyD88-NF-κB and AP-1 signaling pathways to drive IL-10 production by B cells. In a humanized murine model of persistent HCV infection, to neutralize IL-10 produced by B10 cells, mice were treated with pcCD19scFv-IL-10R, which contains the genes coding the anti-CD19 single-chain variable fragment (CD19scFv) and the extracellular domain of IL-10 receptor alpha chain (sIL-10Ra). This treatment resulted in significant reduction of B10 cells in spleen and liver, increase of cytotoxic CD8+ T-cell responses against HCV, and low viral loads in infected humanized mice. Our results indicate that targeting B10 cells via neutralization of IL-10 may offer a novel strategy to enhance anti-HCV immunotherapy.


Assuntos
Linfócitos B Reguladores/imunologia , Hepatite C Crônica/imunologia , Interleucina-10/antagonistas & inibidores , Interleucina-10/imunologia , Animais , Hepacivirus/imunologia , Humanos , Camundongos
10.
Nucleic Acids Res ; 47(1): 56-68, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30462330

RESUMO

Hepatitis C virus (HCV) infection is a major cause of human chronic liver disease and hepatocellular carcinoma. G-quadruplex (G4) is an important four-stranded secondary structure of nucleic acids. Recently, we discovered that the core gene of HCV contains a G4 RNA structure; however, the interaction between the HCV core RNA G4 and host cellular proteins, and the roles of the HCV core RNA G4 in HCV infection and pathogenesis remain elusive. Here, we identified a cellular protein, nucleolin (NCL), which bound and stabilized the HCV core RNA G4 structure. We demonstrated the direct interaction and colocalization between NCL and wild-type core RNA G4 at both in vitro and in cell physiological conditions of the alive virus; however no significant interaction was found between NCL and G4-modified core RNA. NCL is also associated with HCV particles. HCV infection induced NCL mRNA and protein expression, while NCL suppressed wild-type viral replication and expression, but not G4-modified virus. Silencing of NCL greatly enhanced viral RNA replication. Our findings provide new insights that NCL may act as a host factor for anti-viral innate immunity, and binding of cellular NCL with the viral core RNA G4 structure is involved in suppressing HCV replication.


Assuntos
Quadruplex G , Fosfoproteínas/genética , RNA Viral/genética , Proteínas de Ligação a RNA/genética , Proteínas do Core Viral/química , Regulação Viral da Expressão Gênica/genética , Hepacivirus/genética , Hepacivirus/patogenicidade , Hepatite C/genética , Hepatite C/virologia , Humanos , Fosfoproteínas/química , RNA Viral/química , Proteínas de Ligação a RNA/química , Proteínas do Core Viral/genética , Replicação Viral/genética , Nucleolina
11.
Adv Exp Med Biol ; 1325: 219-237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495538

RESUMO

Glycosylation plays an important role in infectious diseases. Many important interactions between pathogens and hosts involve their carbohydrate structures (glycans). Glycan interactions can mediate adhesion, recognition, invasion, and immune evasion of pathogens. To date, changes in many protein N/O-linked glycosylation have been identified as biomarkers for the development of infectious diseases and cancers. In this review, we will discuss the principal findings and the roles of glycosylation of both pathogens and host cells in the context of human important infectious diseases. Understanding the role and mechanism of glycan-lectin interaction between pathogens and hosts may create a new paradigm for discovering novel glycan-based therapies that can lead to eradication or functional cure of pathogens infection.


Assuntos
Doenças Transmissíveis , Lectinas , Glicosilação , Humanos , Evasão da Resposta Imune , Polissacarídeos
12.
Glycobiology ; 30(9): 746-759, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32149341

RESUMO

Tuberculosis (TB) is the leading infectious cause of mortality worldwide, especially in developing countries. However, effective means for TB diagnosis, especially for bacillus-negative (Bn) TB laboratory diagnosis, are urgently needed. In the present study, serum IgG from each tuberculosis patients and healthy controls was purified using affinity chromatography. The samples were then analyzed using mass spectrometry (MS) and ultraperformance liquid chromatography (UPLC) methods. We quantitatively assessed the changes of serum IgG galactosylation in 567 human serum samples including 377 pulmonary TB patients and 190 healthy donors (HDs). We found significantly more agalactosylated (G0) vs monogalactosylated (G1) and digalactosylated (G2) N-glycans of IgG in TB patients, including smear-negative TB patients, than in HDs. The detection rate of TB diagnostic performance by MS for IgG-Gal ratio G0/(G1 + G2 × 2) is 90.48% for bacillus-positive (Bp) and 73.16% for Bn TB patients. Further, combination of MS method with other routine laboratory TB diagnostic methods significantly increased the detection rate to 91.01%-98.39%. Similar results were observed in Mycobacterium tuberculosis (M. tb) infection mouse models. The decrease in galactosylation of IgG in TB patients was also qualitatively confirmed using specific lectin blot assay. Using the above techniques, we can discriminate the content of IgG G0 with terminal N-acetylglucosamine and IgG-Gal ratio G0/(G1 + G2 × 2) between TB patients and HDs. Our data suggest that quantitative analysis of serum-based IgG-Gal ratio G0/(G1 + G2 × 2) could be used for TB auxiliary diagnosis with high effectiveness and feasibility and its combination with other routine laboratory TB diagnostic methods could remarkably improve the detection rate.


Assuntos
Imunoglobulina G/sangue , Tuberculose/diagnóstico , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/sangue
13.
Scand J Immunol ; 91(2): e12843, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31657484

RESUMO

Inflammatory bowel disease (IBD) is a chronic, non-specific, inflammatory gastrointestinal disease that mainly consists of Crohn's disease and ulcerative colitis. However, the aetiology and pathogenesis of IBD are still unclear. B10 (IL-10 producing regulatory B) cells, a subset of regulatory B cells, are known to contribute to intestinal homeostasis and the aberrant frequency of B10 cells is associated with IBD. We have recently reported that B10 cells can be induced by ManLAM (mannose-capped lipoarabinomannan), a major cell-wall lipoglycan of M tb (Mycobacterium tuberculosis). In the current study, the ManLAM-induced B10 cells were adoptively transferred into IL(interleukin)-10-/- mice and the roles of ManLAM-induced B10 cells were investigated in DSS (dextran sodium sulphate)-induced IBD model. ManLAM-induced B10 cells decrease colitis severity in the mice. The B10 cells downregulate Th1 polarization in spleen and MLNs (mesenteric lymph nodes) of DSS-treated mice. These results suggest that IL-10 production by ManLAM-treated B cells contributes to keeping the balance between CD4+ T cell subsets and protect mice from DSS-induced IBD.


Assuntos
Linfócitos B Reguladores/imunologia , Doenças Inflamatórias Intestinais/imunologia , Interleucina-10/metabolismo , Lipopolissacarídeos/metabolismo , Manose/metabolismo , Mycobacterium tuberculosis/metabolismo , Células Th1/imunologia , Animais , Sulfato de Dextrana , Modelos Animais de Doenças , Humanos , Tolerância Imunológica , Doenças Inflamatórias Intestinais/induzido quimicamente , Lipopolissacarídeos/imunologia , Manose/imunologia , Camundongos , Camundongos Knockout
14.
J Am Chem Soc ; 141(13): 5182-5191, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30860368

RESUMO

RNA viruses represent a major global health threat, and the visualization of their RNA genome in infected cells is essential for virological research and clinical diagnosis. Due to the lack of chemical toolkits for the live-cell imaging of viral RNA genomes, especially native viral genomes without labeling and genetic modification, studies on native virus infection at the single-live-cell level are challenging. Herein, taking hepatitis C virus (HCV) as a representative RNA virus, we propose that the innate noncanonical G-quadruplex (G4) structure of viral RNA can serve as a specific imaging target and report a new benzothiazole-based G4-targeted fluorescence light-up probe, ThT-NE, for the direct visualization of the native RNA genome of HCV in living host cells. We demonstrate the use of the ThT-NE probe for several previously intractable applications, including the sensitive detection of individual virus-infected cells by small-molecule staining, real-time monitoring of the subcellular distribution of the viral RNA genome in live cells, and continuous live-cell tracking of the infection and propagation of clinically isolated native HCV. The fluorogenic-probe-based viral RNA light-up system opens up a promising chemical strategy for cutting-edge live-cell viral analysis, providing a potentially powerful tool for viral biology, medical diagnosis, and drug development.


Assuntos
Corantes Fluorescentes/análise , Genoma Viral/genética , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C/patologia , Hepatite C/virologia , Imagem Óptica , RNA Viral/análise , Linhagem Celular Tumoral , Sobrevivência Celular , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Quadruplex G , Hepatite C/diagnóstico por imagem , Humanos , Estrutura Molecular , RNA Viral/genética
15.
Cell Physiol Biochem ; 46(2): 532-545, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29614511

RESUMO

BACKGROUND/AIMS: Exosomal circulating long non-coding RNAs (lncRNAs) in blood are emerging as clinically useful and non-invasive biomarkers for tumor diagnosis. However, normal cells can also secrete exosomes, so it is a prerequisite to obtain tumor-derived exosomes for better understanding of their diagnostic impacts in cancer. In this study, a dual-antibody-functionalized immunoaffinity system was established to isolate exosomes and investigate their lncRNAs expression pattern and clinical significance in prostate cancer (PCa). METHODS: A commercially available kit was used to isolate total exosomes, which were then purified by a dual-antibody-functionalized immunoaffinity system. RT-qPCR was performed to detect the expression of exosomal lncRNAs. Receiver operating characteristic (ROC) curves were plotted to assess the diagnostic value. RESULTS: Expression levels of two lncRNAs in tumor-derived exosomes were significantly higher than those in total exosomes. The levels of SAP30L-AS1 were upregulated in benign prostatic hyperplasia (BPH), and SChLAP1 levels were significantly higher in PCa than in BPH and healthy individuals. The area under the ROC curve indicated that SAP30L-AS1 and SChLAP1 had adequate diagnostic value to distinguish PCa from controls. Two lncRNAs separately combined with prostate specific antigen (PSA) possessed a moderate ability for discrimination. SAP30L-AS1 expression level was related to PSA values and tumor invasion. SChLAP1 expression was significantly higher in patients with higher Gleason scores, and was also effective in differentiating between BPH and PCa when the concentration of PSA was in the gray zone. CONCLUSION: The isolation of tumor-derived exosomes by dual-antibody-functionalized immunoaffinity systems and detection of their lncRNAs in plasma may lead to the identification of suitable biomarkers, with potential diagnostic utility.


Assuntos
Biomarcadores Tumorais/metabolismo , Exossomos/genética , Neoplasias da Próstata/diagnóstico , RNA Longo não Codificante/metabolismo , Idoso , Antígenos de Superfície/metabolismo , Área Sob a Curva , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Difusão Dinâmica da Luz , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Molécula de Adesão da Célula Epitelial/metabolismo , Exossomos/metabolismo , Glutamato Carboxipeptidase II/metabolismo , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Gradação de Tumores , Antígeno Prostático Específico/sangue , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Curva ROC , Tetraspanina 30/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima
16.
Biochem Biophys Res Commun ; 506(4): 990-996, 2018 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-30404730

RESUMO

IL-10 producing B (B10) cells, a subset of regulatory B (Breg) cells, produce IL-10 and play immunosuppressive roles in antitumor immunity. B10 cells are associated with enhanced tumor-aggressiveness and a poorer prognosis. To specifically inhibit the IL-10 secreted by B cells, we constructed the recombinant plasmid pcCD19scFv-IL10R, which contained the gene of anti-CD19 single-chain variable fragment (CD19scFv) and the extracellular domain of IL-10R1. Soluble CD19scFv-IL10R protein was identified in vitro and in vivo after the cells were transfected with pcCD19scFv-IL10R plasmid or the mice were injected with the plasmid. The fusion protein had the bispecific ability to target both IL-10 and CD19 molecules in vitro. Intramuscularly (i.m.) injecting mice with pcCD19scFv-IL-10R plasmid inhibited hepatocellular carcinoma growth in vivo. Mice treated with pcCD19scFv-IL-10R showed a significant reduction in B10 cells and regulatory T (Treg) cells, but an increase in the anti-tumor Th1 immune response and the cytotoxic CD8+ T cell response. Thus, targeting B10 cells by CD19scFv-IL10R molecule may offer a new avenue for tumor therapy.


Assuntos
Antígenos CD19/metabolismo , Linfócitos B Reguladores/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Receptores de Interleucina-10/metabolismo , Anticorpos de Cadeia Única/imunologia , Animais , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Imunidade , Camundongos Endogâmicos C57BL , Plasmídeos/metabolismo , Ligação Proteica , Proteínas Recombinantes de Fusão/metabolismo , Soro/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia
17.
Immunity ; 30(3): 397-407, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19285439

RESUMO

Viral infection activates transcription factors NF-kappaB and IRF3, which collaborate to induce type I interferons (IFNs) and elicit innate antiviral response. MITA (also known as STING) has recently been identified as an adaptor that links virus-sensing receptors to IRF3 activation. Here, we showed that the E3 ubiquitin ligase RNF5 interacted with MITA in a viral-infection-dependent manner. Overexpression of RNF5 inhibited virus-triggered IRF3 activation, IFNB1 expression, and cellular antiviral response, whereas knockdown of RNF5 had opposite effects. RNF5 targeted MITA at Lys150 for ubiquitination and degradation after viral infection. Both MITA and RNF5 were located at the mitochondria and endoplasmic reticulum (ER) and viral infection caused their redistribution to the ER and mitochondria, respectively. We further found that virus-induced ubiquitination and degradation of MITA by RNF5 occurred at the mitochondria. These findings suggest that RNF5 negatively regulates virus-triggered signaling by targeting MITA for ubiquitination and degradation at the mitochondria.


Assuntos
Proteínas de Ligação a DNA/imunologia , Regulação da Expressão Gênica , Proteínas de Membrana/metabolismo , Viroses/imunologia , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Células Cultivadas , Proteínas de Ligação a DNA/genética , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/genética , Fator Gênico 3 Estimulado por Interferon, Subunidade gama/metabolismo , Interferon beta/genética , Interferon beta/metabolismo , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais , Ubiquitina-Proteína Ligases , Regulação para Cima , Vírus/imunologia
18.
J BUON ; 23(3): 579-586, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30003722

RESUMO

PURPOSE: MicroRNAs are expressed abnormally in colorectal cancer (CRC) and could participate in its development. In this study we aimed to explore the molecular mechanisms of miR-503 in the genesis of CRC. METHODS: The relative expression of miR-503 and programmed cell death 4 (PDCD4) tumor suppressor in CRC tissues and cell lines were detected by qRT-PCR and Western blot. Cell migration and cell invasion were assessed by transwell assay. Moreover, the confirmation of the direct target of miR-503 in CRC was performed by luciferase reporter assay. RESULTS: The expression of miR-503 was increased remarkably in CRC, while PDCD4 decreased. Moreover, PDCD4 was verified as a specific target of miR-503 in CRC and it could reverse the effect of miR-503 on CRC cells. Furthermore, the abnormal expression of miR-503 played an important role in regulating of the development of CRC cells. In addition, PDCD4 protein expression and miR-503 mRNA expression were negatively correlated in CRC tissues. CONCLUSION: The inhibitory effect of miR-503 in CRC was realized by the upregulation of PDCD4, suggesting that miR-503/PDCD4 axis might play a critical role in CRC and could possibly be a therapeutic target.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Movimento Celular/fisiologia , Neoplasias Colorretais/metabolismo , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular Tumoral , Separação Celular/métodos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células HCT116 , Células HEK293 , Células HT29 , Humanos , MicroRNAs/administração & dosagem , MicroRNAs/biossíntese , MicroRNAs/genética , Invasividade Neoplásica , Proteínas de Ligação a RNA/genética , Transfecção
19.
Biochim Biophys Acta ; 1860(8): 1764-75, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26278021

RESUMO

BACKGROUND: The development of an efficient vaccine and broadly cross-neutralizing antibodies of hepatitis C virus (HCV) remains a priority. The heavily glycosylated viral envelope glycoprotein E1E2 complex is a candidate vaccine antigen. Bacteria-derived unmethylated CpG DNA, a potent stimulator of immune cells, is important for vaccine research. METHODS: Here, the immunogenicities of wild type (WT) E1E2, five N-glycosylation site mutated E1E2 glycoproteins, and five CpG-coupled E1E2 N-glycosylation mutated glycoproteins were analyzed in BALB/c mice by DNA vaccination using in vivo electroporation. RESULTS: The E1E2 protein expression levels were examined and shown to be unaffected by these N-glycosylation mutations. We found that a CpG-coupled E1-N209D-E2-N430D DNA vaccine (named CpG-E1E2-M4) induced the highest cellular immune response compared to the WT E1E2, CpG-E1E2, and other mutants. Furthermore, the CpG-E1E2-M4 anti-serum effectively neutralized the infection of cell-cultured HCV (HCVcc, genotype 2a)- and HCV pseudo particles (HCVpp, genotypes 1 to 7) to Huh-7.5.1 hepatocytes. Additionally, CpG-E1E2-M4 enhanced the Interleukin-12 (IL-12) production and antigen-presenting activity of CD11c(+) dendritic cells (DCs) by inducing CD4(+) Th1 polarization and the production of perforin and granzyme B (GrB) in CD8(+) T cells. CONCLUSIONS: As our knowledge this is the first study revealing that the naturally poor immunogenicity of E1E2 can be enhanced by the deletion of N-glycans combined with the addition of immune activator CpG by DNA vaccination. GENERAL SIGNIFICANCE: Deletion of N-glycans can enhance viral immunogenicity. The selected CpG-E1E2-M4 mutant is a novel potential HCV DNA vaccine that elicits enhanced CD4(+) Th1 and CD8(+) T cell responses and neutralizing antibody production against HCV infection. This article is part of a Special Issue entitled "Glycans in personalised medicine" Guest Editor: Professor Gordan Lauc.


Assuntos
Anticorpos Neutralizantes/imunologia , Apresentação de Antígeno , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/imunologia , Hepatite C/imunologia , Vacinas de DNA/imunologia , Proteínas do Envelope Viral/imunologia , Vacinas contra Hepatite Viral/imunologia , Substituição de Aminoácidos , Animais , Linfócitos T CD8-Positivos , Linhagem Celular , Ilhas de CpG , Células Dendríticas/imunologia , Feminino , Células HEK293 , Células HeLa , Hepacivirus/genética , Hepatite C/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Mutação de Sentido Incorreto , Células Th1/imunologia , Vacinas de DNA/genética , Vacinas de DNA/farmacologia , Proteínas do Envelope Viral/genética , Vacinas contra Hepatite Viral/genética
20.
Immunology ; 151(4): 433-450, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28380665

RESUMO

Human ficolin-2 (FCN-2) and mouse ficolin-A (FCN-A, a ficolin-2-like molecule in mouse) are activators of the lectin complement pathway, present in normal plasma and usually associated with infectious diseases, but little is known about the role of FCN-A/2 in inflammatory bowel disease (IBD). In our present study, we found that patients with IBD exhibited much higher serum FCN-2 levels than healthy controls. In the dextran sulphate sodium-induced acute colitis mouse model, FCN-A knockout mice showed much milder disease symptoms with less histological damage, lower expression levels of pro-inflammatory cytokines [interleukin-6 (IL-6), IL-1ß and tumour necrosis factor-α (TNF-α)], chemokines (CXCL1/2/10 and CCL4) and higher levels of the anti-inflammatory cytokine IL-10 compared with wild-type mice. We demonstrated that FCN-A/2 exacerbated the inflammatory pathogenesis of IBD by stimulating M1 polarization through the TLR4/MyD88/MAPK/NF-κB signalling pathway in macrophages. Hence, our data suggest that FCN-A/2 may be used as a novel therapeutic target for IBD.


Assuntos
Diferenciação Celular , Colite/imunologia , Inflamação/imunologia , Lectinas/metabolismo , Macrófagos/imunologia , Animais , Células Cultivadas , Lectina de Ligação a Manose da Via do Complemento/genética , Citocinas/metabolismo , Humanos , Lectinas/genética , Ativação de Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo , Ficolinas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA