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1.
J Nat Prod ; 86(9): 2081-2090, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37676247

RESUMO

Nine new ergosteroids (1-9) and seven known ones (10-16) were isolated from Talaromyces adpressus. Their structures and absolute configurations were determined by the interpretation of NMR spectroscopic data, HRESIMS, ECD calculations, and single-crystal X-ray diffraction analyses. Structurally, compound 1 was an ergosteroid with two epoxy and a 3α-OH group at ring A, while compounds 8 and 9 had a contracted ring A with a peroxy bridge between C-3 and C-9, which were reported for the first time. Compounds 2-6, 9, 11, and 15 displayed cytotoxic activities with IC50 values ranging from 0.4 to 32 µM, and compound 7 exhibited an immunosuppressive effect against LPS-induced B lymphocyte proliferation with an IC50 value of 8.6 µM. The structure-activity relationships of these compounds are briefly discussed.


Assuntos
Antineoplásicos , Talaromyces , Proliferação de Células , Cristalografia por Raios X
2.
Environ Res ; 226: 115702, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36931372

RESUMO

The accurate determination of waster sludge water content is crucial to sludge dewatering treatment and its disposal management. Though previous studies highlight the great advantages of low-field nuclear magnetic resonance (LF-NMR) in the determination of sludge water content, its accuracy and applicability are not well studied. Herein, this study investigated the settling of operating parameters and the properties of sludge samples on the accuracy and applicability of LF-NMR method in measuring sludge water content. The results showed that the setting of basic parameters such as standard curve, number of scanning times (NS) and sample weight affected the accuracy of sludge water content by LF-NMR. The standard calibration curve constructed by 3 g/L CuSO4, NS = 8 and the sample weight of about 5 g, were suitable for the accurate determination of sludge water content. Furthermore, the existence of magnetic substances in sludge can affect the distribution gradient of main magnetic field, and thus restricted the applicability of LF-NMR. The saturation magnetization of chemical reagents strongly correlated with the measured relative errors of sludge water content (r = 0.995, p < 0.01), the greater the saturation magnetization of the magnetic material, the greater the error of the test results. On the whole, it is necessary to fully consider the influence of process parameters and sludge properties to evaluate the accuracy and applicability of the LF-NMR method, rather than simply copying the parameters in literatures.


Assuntos
Esgotos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Água/química , Espectroscopia de Ressonância Magnética
3.
BMC Med ; 20(1): 436, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352415

RESUMO

BACKGROUND: A major hand-foot-and-mouth disease (HFMD) pathogen, coxsackievirus A16 (CVA16), has predominated in several of the last 10 years and caused the largest number of HFMD outbreaks between 2011 and 2018 in China. We evaluated the efficacy of maternal anti-CVA16 antibody transfer via the placenta and explored the dynamics of maternal and natural infection-induced neutralizing antibodies in children. METHODS: Two population-based longitudinal cohorts in southern China were studied during 2013-2018. Participants were enrolled in autumn 2013, including 2475 children aged 1-9 years old and 1066 mother-neonate pairs, and followed for 3 years. Blood/cord samples were collected for CVA16-neutralizing antibody detection. The maternal antibody transfer efficacy, age-specific seroprevalence, geometric mean titre (GMT) and immune response kinetics were estimated. RESULTS: The average maternal antibody transfer ratio was 0.88 (95% CI 0.80-0.96). Transferred maternal antibody levels declined rapidly (half-life: 2.0 months, 95% CI 1.9-2.2 months). The GMT decayed below the positive threshold (8) by 1.5 months of age. Due to natural infections, it increased above 8 after 1.4 years and reached 32 by 5 years of age, thereafter dropping slightly. Although the average duration of maternal antibody-mediated protection was < 3 months, the duration extended to 6 months on average for mothers with titres ≥ 64. CONCLUSIONS: Anti-CVA16 maternal antibodies are efficiently transferred to neonates, but their levels decline quickly. Children aged 0-5 years are the main susceptible population and should be protected by CVA16 vaccination, with the optimal vaccination time between 1.5 months and 1 year of age.


Assuntos
Enterovirus Humano A , Enterovirus , Doença de Mão, Pé e Boca , Criança , Recém-Nascido , Animais , Humanos , Lactente , Pré-Escolar , Estudos Soroepidemiológicos , Estudos Longitudinais , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/prevenção & controle , Anticorpos Neutralizantes , China/epidemiologia , Estudos de Coortes
4.
Clin Infect Dis ; 67(11): 1729-1735, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29688329

RESUMO

Background: Hand, foot, and mouth disease (HFMD) represents a substantial disease burden in the Western Pacific region. We investigated the spectrum of causative enteroviruses of HFMD, and evaluated different clinical samples' diagnostic yield for enteroviruses. Methods: We enrolled pediatric patients hospitalized for HFMD among 6 hospitals in Anhua County, Hunan Province, China between October 2013 and September 2016. Throat swabs and stool samples (or rectal swabs) were collected to detect the enterovirus serotypes by real-time reverse-transcription polymerase chain reaction (PCR) or nested PCR. Results: Among the 2836 patients, only 1 developed severe illness. Seventeen serotypes were identified in 2401 patients (85%), with the most frequently detected being CV-A16 (29% [814]), CV-A6 (28% [784]), EV-A71 (17% [491]), CV-A10 (4% [114]), and CV-A4 (2% [53]). Children were younger in CV-A6, CV-A10, and CV-A4 infections (median, 12 months; interquartile range [IQR], 12-24 months) than EV-A71 and CV-A16 infections (median, 24 months; IQR, 12-36 months; P < .05). The predominant enterovirus serotype shifted between CV-A16 and CV-A6 during the 3 years. Stool had a higher diagnostic yield (89%) than rectal (77%) and throat swabs (74%). Detection rates reached 93% when testing stools followed by throat swabs if stools were negative, and 89% when testing rectal swabs followed by throat swabs if rectal swabs were negative. Conclusions: Our results provide a virological benchmark for future surveillance and diagnostics. Continuous comprehensive virological surveillance is essential, especially after implementation of the EV-A71 vaccine in China, to monitor serotype replacement and the vaccine's impact.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/classificação , Fezes/virologia , Doença de Mão, Pé e Boca/virologia , Faringe/virologia , Pré-Escolar , China/epidemiologia , Infecções por Enterovirus/diagnóstico , Infecções por Enterovirus/epidemiologia , Feminino , Doença de Mão, Pé e Boca/diagnóstico , Doença de Mão, Pé e Boca/epidemiologia , Hospitalização , Humanos , Lactente , Masculino , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Sorogrupo
5.
J Biol Chem ; 288(3): 1634-42, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23192351

RESUMO

The forkhead box M1 (FoxM1) is a key transcription factor regulating multiple aspects of cell biology. Prior studies have shown that FoxM1 is overexpressed in a variety of human tumors, including brain tumor, and plays a critical role in cancer development and progression. In this study we found that FoxM1 was up-regulated by heat shock factor 1 (HSF1) under heat shock stress condition in multiple cell lines. Knockdown of HSF1 with HSF1 siRNA or inhibition of HSF1 with a HSF1 inhibitor abrogated heat shock-induced expression of FoxM1. Genetic deletion of HSF1 in mouse embryo fibroblast cells also abolished heat shock stress-induced FoxM1 expression. Moreover, we showed that HSF1 directly bound to FoxM1 promoter and increased FoxM1 promoter activity. Furthermore, we demonstrated that FoxM1 was required for the G(2)-M phase progression through regulating Cdc2, Cdc20, and Cdc25B under a mild heat shock stress but enhanced cell survival under lethal heat shock stress condition. Finally, in human glioblastoma specimens, FoxM1 overexpression correlated with elevated HSF1 expression. Our results indicate that FoxM1 is regulated by HSF1 and is critical for HSF1-mediated heat shock response. We demonstrated a novel mechanism of stress resistance controlled by HSF1 and a new HSF-FoxM1 connection that mediates cellular thermotolerance.


Assuntos
Proteínas de Ligação a DNA/genética , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Resposta ao Choque Térmico/genética , Fatores de Transcrição/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Embrião de Mamíferos , Fibroblastos/citologia , Fibroblastos/metabolismo , Proteína Forkhead Box M1 , Fatores de Transcrição Forkhead/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Técnicas de Silenciamento de Genes , Glioblastoma/metabolismo , Glioblastoma/patologia , Fatores de Transcrição de Choque Térmico , Temperatura Alta , Humanos , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica , RNA Interferente Pequeno/genética , Transdução de Sinais , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo
6.
Dalton Trans ; 53(19): 8335-8346, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38666487

RESUMO

Vanadium-based oxides are considered potential cathode materials for aqueous zinc ion batteries (AZIBs) due to their distinctive layered (or tunnel) structure suitable for zinc ion storage. However, the structural instability and sluggish kinetics of vanadium-based oxides have limited their capacity and cycling stability for large-scale applications. To overcome these shortcomings, here a porous vanadium-based oxide doped with zinc ions and carbon with the molecular formula ZnV2O4@C (ZVO@C) as the cathode material is synthesized by the pyrolysis of a bimetallic MOF precursor containing Zn/V. This electrode demonstrates a remarkable specific capacity of 425 mA h g-1 at 0.5 A g-1 and excellent cycling stability with about 97% capacity retention after 1000 cycles at 10 A g-1. The excellent electrochemical performance of ZVO@C can be attributed to more reaction active sites and the faster reaction kinetics for zinc ion diffusion and storage brought about by the porous layered spinel-type tunnel structure with high surface area and massive mesoporosity, as well as the enhanced electron transport efficiency and more stable channel structure achieved from the doped conductive carbon. The reaction mechanism and structural evolution of the ZVO@C electrode are analyzed using X-ray diffraction and X-ray photoelectron spectroscopy, revealing the formation of a new phase of ZnxV2O5·nH2O during the first charge, which participates in reversible cycling together with ZVO@C during the charging and discharging processes. Moreover, the energy storage mechanism is revealed, in which zinc ions and hydrogen ions jointly participate in intercalation and extraction. The present study demonstrates that constructing composite vanadium-based oxides based on bimetallic organic frameworks as precursor templates is an effective strategy for the development of high-performance cathode materials for AZIBs.

7.
Clin Rheumatol ; 43(2): 645-655, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38097864

RESUMO

OBJECTIVE: The semaphorins are membrane or secreted proteins first identified in neural development. Semaphorin 4D (Sema4D) is the first family member found to have immune properties. We evaluated the potential of Sema4D as a marker for rheumatoid arthritis (RA) disease activity, singly and in combination with other known biomarkers including rheumatoid factor (RF) and C-reactive protein (CRP). METHODS: Three hundred and eleven RA patients were enrolled. The patients were divided into three groups based on their disease activity in 28 joints (DAS28): mild, moderate, and severe. The healthy group included 40 healthy individuals. SerumSema4D was measured by quantitative ELISA and the specificity and sensitivity of biomarkers were evaluated by generating a receiver operating characteristic (ROC) curve to analyze their diagnostic accuracy. RESULTS: Serum Sema4D levels in the moderate and severe RA groups were elevated significantly above those of the controls (P < 0.01), while levels in the mild RA and control groups did not differ significantly (P > 0.05). The Sema4D cutoff threshold was 15.7 ng/ml when the DAS28 was applied as a reference. Compared to the erythrocyte sedimentation rate (ESR and CRP, Sema4D had the highest specificity (96.8%) and area under the curve (0.80) for diagnosing RA activity. The highest specificity (100%) for the biomarker combinations was obtained when Sema4D was combined with CRP and anti-CCP, the combination of the Sema4D combined with ESR and anti-CCP had the highest sensitivity (99.35%). According to this result, a new model for jointly calculating RA activity of Sema4D,anti-CCP and CRP was constructed. Meanwhile another model is established by using the method of multivariate analysis.Model comparison results showed the the multiple regression algorithm method fitted the patients' disease activity better. CONCLUSION: The serum Sema 4D level effectively reflects moderate to severe RA activity. Sema4D levels can be used together with conventional RA biomarkers to increase the diagnostic power of RA activity. The multiple regression algorithm method is promising in disease activity calculation.


Assuntos
Antígenos CD , Artrite Reumatoide , Semaforinas , Humanos , Anticorpos Antiproteína Citrulinada , Biomarcadores , Proteína C-Reativa/metabolismo
8.
Fitoterapia ; 173: 105790, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158160

RESUMO

Three new furano-lactones, asperilactones A-C (1-3), and two known compounds silvaticol (4) and violaceic acid (5) were isolated from an ethanol extract of Aspergillus nidulans, a fungus isolated from the Annelida Whitmania pigra Whitman (Haemopidae). Their structures were elucidated by a combination of spectroscopy, ECD calculations, comparing optical rotation values, and single-crystal X-ray diffraction analyses. Asperilactone A (1) represented the first example of furano-lactone with an unusual 2-thia-6-oxabicyclo[3.3.0]octane ring system. Asperilactones A and B showed weak toxicity against the HL-60 and RKO.


Assuntos
Aspergillus nidulans , Lactonas/química , Estrutura Molecular , Cristalografia por Raios X , Análise Espectral
9.
Mol Ther ; 20(9): 1800-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22588271

RESUMO

Exhaustion of CD8(+) T cells and upregulation of programmed death 1 (PD-1), a negative regulator of T cell activation, are characteristic features of individuals chronically infected with human immunodeficiency virus type 1. In a previous study, we showed in mice that a dendritic cell-directed lentiviral vector (DCLV) system encoding the human immunodeficiency virus (HIV)-1 Gag protein was an efficient vaccine modality to induce a durable Gag-specific T cell immune response. In this study, we demonstrate that blocking of the PD-1/PD-1 ligand (PD-L) inhibitory signal via an anti-PD-L1 antibody generated an enhanced HIV-1 Gag-specific CD8(+) immune response following both a single round of DCLV immunization and a homologous prime/boost regimen. The prime/boost regimen combined with PD-L1 blockade generated very high levels of Gag-specific CD8(+) T cells comprising several valuable features: improved ability to produce multiple cytokines, responding to a broader range of Gag-derived epitopes, and long-lasting memory. This enhanced cellular immune response generated by DCLV immunization combined with anti-PD-L1 blockade correlated with improved viral control following challenge with Gag-expressing vaccinia virus. Taken together, our studies offer evidence to support the use of PD-1/PD-L1 blockade as an adjuvant modality to enhance antigen-specific immune responses elicited by T cell-based immunizations such as DCLV.


Assuntos
Vacinas contra a AIDS/imunologia , Antígenos de Diferenciação/imunologia , Antígeno B7-H1/antagonistas & inibidores , Células Dendríticas/imunologia , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Vacinas contra a AIDS/administração & dosagem , Animais , Antígenos de Diferenciação/genética , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Células Dendríticas/virologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Vetores Genéticos , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/genética , Humanos , Imunidade Celular , Imunização Secundária , Lentivirus/genética , Ativação Linfocitária , Camundongos , Receptor de Morte Celular Programada 1 , Vaccinia virus , Produtos do Gene gag do Vírus da Imunodeficiência Humana
10.
Dalton Trans ; 52(38): 13797-13807, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37721207

RESUMO

At present, vanadium-based cathodes for aqueous zinc-ion batteries (AZIBs) are limited by their slow reaction kinetics, poor electrical conductivity, and low capacity retention. To overcome these problems, here, we design a layered porous Mn0.18V2O5@C as the cathode material for AZIBs using a manganese-containing metal-organic framework as a template through a simple solvothermal method. Such an electrode delivers an excellent specific capacity (380 mA h g-1 at 0.1 A g-1) accompanied by superior cycling stability (about 85% capacity retention for 2000 cycles at 6 A g-1). The excellent electrochemical performance of Mn0.18V2O5@C is ascribed to the improved interface activity including smooth zinc ion transport, abundant ion reaction active sites and accelerated charge transfer resulting from the coordination of the porous structure, doped conductive carbon, and the stable channel structure derived from the pillar effect of doping manganese ions, preventing a premature collapse of the electrode structure. It is also revealed by structural evolution analysis that the residual zinc ions also combine with the original Mn0.18V2O5 to form a ZnxMnyV2O5 phase, which serves as an additional structural pillar and in the meantime, also participates in the following cycles. These favorable electrochemical results suggest that Mn0.18V2O5@C is a suitable cathode material for AZIBs.

11.
Acta Biomater ; 172: 260-271, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37806373

RESUMO

Removing excessively produced cytokines is of paramount significance in blood purification therapy for hypercytokinemia-associated diseases. In this study, we devised a conduit that is modified with nanobodies (Nb) and incorporates static mixers (Nb-SMC) to eliminate surplus cytokines from the bloodstream. The low-pressure-drop (LPD) static mixer, with each unit featuring two 90°-crossed blades, was strategically arranged in a tessellated pattern on the inner wall of the conduit to induce turbulent mixing effects during the flow of blood. This arrangement enhances mass transfer and molecular diffusion, thereby assisting in the identification and elimination of cytokines. By utilizing computational fluid dynamics (CFD) studies, the Nb-SMC was rationally designed and prepared, ensuring an optimal interval between two mixer units (H/G = 2.5). The resulting Nb-SMC exhibited a remarkable selective clearance of IL-17A, reaching up to 85 %. Additionally, the process of Nb immobilization could be adjusted to achieve the simultaneous removal of multiple cytokines from the bloodstream. Notably, our Nb-SMC displayed good blood compatibility without potential adverse effects on the composition of human blood. As the sole documented static mixer-integrated conduit capable of selectively eliminating cytokines at their physiological concentrations, it holds promise in the clinical potential for hypercytokinemia in high-risk patients. STATEMENT OF SIGNIFICANCE: High-efficient cytokines removal in critical care still remains a challenge. The conduit technique we proposed here is a brand-new strategy for cytokines removal in blood purification therapy. On the one hand, nanobody endows the conduit with specific recognition of cytokine, on the other hand, the build-in static mixer enhances the diffusion of antigenic cytokine to the ligand. The combination of these two has jointly achieved the efficient and specific removal of cytokine. This innovative material is the only reported artificial biomaterial capable of selectively eliminating multiple cytokines under conditions close to clinical practice. It has the potential to improve outcomes for patients with hypercytokinemia and reduce the risk of adverse events associated with current treatment modalities.


Assuntos
Citocinas , Hemoperfusão , Humanos , Hemoperfusão/métodos , Síndrome da Liberação de Citocina , Próteses e Implantes
12.
Front Immunol ; 14: 1173187, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744384

RESUMO

Objective: Although Leflunomide (LEF) is effective in treating rheumatoid arthritis (RA), there are still a considerable number of patients who respond poorly to LEF treatment. Till date, few LEF efficacy-predicting biomarkers have been identified. Herein, we explored and developed a DNA methylation-based predictive model for LEF-treated RA patient prognosis. Methods: Two hundred forty-five RA patients were prospectively enrolled from four participating study centers. A whole-genome DNA methylation profiling was conducted to identify LEF-related response signatures via comparison of 40 samples using Illumina 850k methylation arrays. Furthermore, differentially methylated positions (DMPs) were validated in the 245 RA patients using a targeted bisulfite sequencing assay. Lastly, prognostic models were developed, which included clinical characteristics and DMPs scores, for the prediction of LEF treatment response using machine learning algorithms. Results: We recognized a seven-DMP signature consisting of cg17330251, cg19814518, cg20124410, cg21109666, cg22572476, cg23403192, and cg24432675, which was effective in predicting RA patient's LEF response status. In the five machine learning algorithms, the support vector machine (SVM) algorithm provided the best predictive model, with the largest discriminative ability, accuracy, and stability. Lastly, the AUC of the complex model(the 7-DMP scores with the lymphocyte and the diagnostic age) was higher than the simple model (the seven-DMP signature, AUC:0.74 vs 0.73 in the test set). Conclusion: In conclusion, we constructed a prognostic model integrating a 7-DMP scores with the clinical patient profile to predict responses to LEF treatment. Our model will be able to effectively guide clinicians in determining whether a patient is LEF treatment sensitive or not.


Assuntos
Artrite Reumatoide , Metilação de DNA , Humanos , Leflunomida/uso terapêutico , Prognóstico , DNA , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética
13.
Cell Rep Med ; 4(8): 101130, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37490914

RESUMO

Signal regulatory protein (SIRPα) is an immune inhibitory receptor expressed by myeloid cells to inhibit immune cell phagocytosis, migration, and activation. Despite the progress of SIRPα and CD47 antagonist antibodies to promote anti-cancer immunity, it is not yet known whether SIRPα receptor agonism could restrain excessive autoimmune tissue inflammation. Here, we report that neutrophil- and monocyte-associated genes including SIRPA are increased in inflamed tissue biopsies from patients with rheumatoid arthritis and inflammatory bowel diseases, and elevated SIRPA is associated with treatment-refractory ulcerative colitis. We next identify an agonistic anti-SIRPα antibody that exhibits potent anti-inflammatory effects in reducing neutrophil and monocyte chemotaxis and tissue infiltration. In preclinical models of arthritis and colitis, anti-SIRPα agonistic antibody ameliorates autoimmune joint inflammation and inflammatory colitis by reducing neutrophils and monocytes in tissues. Our work provides a proof of concept for SIRPα receptor agonism for suppressing excessive innate immune activation and chronic inflammatory disease treatment.


Assuntos
Colite , Neoplasias , Humanos , Fagocitose , Neoplasias/tratamento farmacológico , Neutrófilos/metabolismo , Inflamação/patologia , Colite/metabolismo
14.
Biotechnol Bioeng ; 109(6): 1551-60, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22179950

RESUMO

Lentiviral vectors (LVs) enveloped with an engineered Sindbis virus glycoprotein can specifically bind to dendritic cells (DCs) through the surface receptor DC-SIGN and induce antigen expression, thus providing an efficient method for delivering DC-directed vaccines. In this study, we constructed a stable producer line (LV-MGFP) for synthesizing DC-SIGN-targeted HIV-1-based LVs (DC-LVs) encoding green fluorescent protein (GFP) by a concatemeric array transfection technique. We demonstrated that the established stable clones could routinely produce vector supernatants with titers above 10(7) transduction units per milliliter (TU/mL) during a continuous 3-month cell passage. The producer cells were also capable of generating similar titers of DC-LVs in serum-free medium. Moreover, the addition of 1-deoxymannojirimycin (DMJ) enabled the producer cells to manufacture DC-LVs with both improved titers and enhanced potency to evoke antigen-specific CD8(+) T cell responses in mice. The stable lines could accommodate the replacement of the internal murine stem cell virus (MSCV) promoter with the human ubiquitin-C (Ubi) promoter in the lentiviral backbone. The resulting DC-LVs bearing Ubi exhibited the enhanced potency to elicit vaccine-specific immunity. Based on accumulated evidence, our studies support the application of this production method in manufacturing DC-LVs for preclinical and clinical testing of novel DC-based immunization.


Assuntos
Biotecnologia/métodos , Células Dendríticas/imunologia , Vetores Genéticos , HIV-1/genética , Tecnologia Farmacêutica/métodos , Transdução Genética , Vacinação/métodos , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular , Meios de Cultura Livres de Soro , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Sindbis virus/genética , Coloração e Rotulagem , Técnicas de Cultura de Tecidos/métodos , Proteínas do Envelope Viral/genética , Carga Viral
15.
Mol Ther ; 19(5): 942-50, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21326219

RESUMO

Human embryonic stem (hES) cells are renewable cell sources that have potential applications in regenerative medicine. The development of technologies to produce permanent and site-specific genome modifications is in demand to achieve future medical implementation of hES cells. We report herein that a baculoviral vector (BV) system carrying zinc-finger nucleases (ZFNs) can successfully modify the hES cell genome. BV-mediated transient expression of ZFNs specifically disrupted the CCR5 locus in transduced cells and the modified cells exhibited resistance to HIV-1 transduction. To convert the BV to a gene targeting vector, a DNA donor template and ZFNs were incorporated into the vector. These hybrid vectors yielded permanent site-specific gene addition in both immortalized human cell lines (10%) and hES cells (5%). Modified hES cells were both karyotypically normal and pluripotent. These results suggest that this baculoviral delivery system can be engineered for site-specific genetic manipulation in hES cells.


Assuntos
Desoxirribonucleases/genética , Células-Tronco Embrionárias/metabolismo , Nucleopoliedrovírus/genética , Receptores CCR5/genética , Linhagem Celular , Desoxirribonucleases/metabolismo , Citometria de Fluxo , Marcação de Genes , Vetores Genéticos , HIV-1/genética , Humanos , Mutação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução Genética , Transgenes , Dedos de Zinco
16.
Proc Natl Acad Sci U S A ; 106(48): 20382-7, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19918062

RESUMO

Lentivectors (LVs) have attracted considerable interest for their potential as a vaccine delivery vehicle. In this study, we evaluate in mice a dendritic cell (DC)-directed LV system encoding the Gag protein of human immunodeficiency virus (HIV) (LV-Gag) as a potential vaccine for inducing an anti-HIV immune response. The DC-directed specificity is achieved through pseudotyping the vector with an engineered Sindbis virus glycoprotein capable of selectively binding to the DC-SIGN protein. A single immunization by this vector induces a durable HIV Gag-specific immune response. We investigated the antigen-specific immunity and T-cell memory generated by a prime/boost vaccine regimen delivered by either successive LV-Gag injections or a DNA prime/LV-Gag boost protocol. We found that both prime/boost regimens significantly enhance cellular and humoral immune responses. Importantly, a heterologous DNA prime/LV-Gag boost regimen results in superior Gag-specific T-cell responses as compared with a DNA prime/adenovector boost immunization. It induces not only a higher magnitude response, as measured by Gag-specific tetramer analysis and intracellular IFN-gamma staining, but also a better quality of response evidenced by a wider mix of cytokines produced by the Gag-specific CD8(+) and CD4(+) T cells. A boosting immunization with LV-Gag also generates T cells reactive to a broader range of Gag-derived epitopes. These results demonstrate that this DC-directed LV immunization is a potent modality for eliciting anti-HIV immune responses.


Assuntos
Vacinas contra a AIDS/imunologia , Células Dendríticas/imunologia , Vetores Genéticos/imunologia , HIV-1 , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Lentivirus , Camundongos , Camundongos Endogâmicos BALB C , Sindbis virus/metabolismo , Linfócitos T/imunologia
17.
Nat Commun ; 13(1): 7280, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435844

RESUMO

Enterovirus A71 (EV-A71)-related hand, foot, and mouth disease (HFMD) imposes a substantial clinical burden in the Asia Pacific region. To inform policy on the introduction of the EV-A71 vaccine into the National Immunization Programme, we investigated the seroepidemiological characteristics of EV-A71 in two prospective cohorts of children in southern China conducted between 2013 and 2018. Our results show that maternal antibody titres declined rapidly in neonates, with over half becoming susceptible to EV-A71 at 1 month of age. Between 6 months and 2 years of age, over 80% of study participants were susceptible, while one third remained susceptible at 5 years old. The highest incidence of EV-A71 infections was observed in children aged 5-6 months. Our findings support EV-A71 vaccination before 6 months for birth cohorts in southern China, potentially with a one-time catch-up vaccination for children 6 months-5 years old. More regionally representative longitudinal seroepidemiological studies are needed to further validate these findings.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Criança , Recém-Nascido , Humanos , Pré-Escolar , Doença de Mão, Pé e Boca/epidemiologia , Estudos Prospectivos , Estudos Soroepidemiológicos , Infecções por Enterovirus/epidemiologia , China/epidemiologia , Antígenos Virais
18.
Hum Vaccin Immunother ; 17(2): 592-600, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32643509

RESUMO

China has achieved high vaccination coverage under the Expanded Program on Immunization (EPI) in children 1-2 years of age. However, a knowledge gap exists regarding vaccination coverage and timeliness for children >2 years of age. As such, this study aimed to estimate coverage and timeliness for all EPI and selected non-EPI vaccines within a rural area of China. Immunization data for 5091 children, born between September 2003 and November 2015, were collected from vaccination cards obtained during sero-surveillance follow-up visits and/or from the Hunan immunization information system. For each dose of both EPI and non-EPI vaccines, vaccination coverage and timeliness were calculated, and temporal variations were examined across birth cohorts. We found coverage for EPI vaccines scheduled for <12 months was 97.1%-99.4%. However, for EPI vaccines scheduled at 6 years coverage was 44.4%-51.7%. The timeliness for EPI vaccines was generally poor, especially for EPI vaccines introduced after 2008 or scheduled for administration at ≥12 months, with a maximum of 35.4% of children vaccinated according to schedule. Despite this, we found increasing trends in vaccination coverage and improvements in timeliness for EPI vaccines. However, for non-EPI vaccines, we found only moderate increases, and in some cases decreases, in vaccination coverage. This study demonstrates the success and improvement of the Chinese immunization program, but also highlights some challenges to be addressed. We recommend that future changes in vaccine practice and policy should primarily focus on improving coverage and timeliness of vaccines introduced after 2008, and/or scheduled for administration ≥12 months.


Assuntos
Cobertura Vacinal , Vacinas , Criança , China , Humanos , Programas de Imunização , Esquemas de Imunização , Lactente , Vacinação
19.
Cell Death Dis ; 12(7): 693, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34247201

RESUMO

Nuclear factor erythroid 2-related factor 2 (NRF2) is aberrantly activated in about 93% of pancreatic cancers. Activated NRF2 regulates multiple downstream molecules involved in cancer cell metabolic reprogramming, translational control, and treatment resistance; however, targeting NRF2 for pancreatic cancer therapy remains largely unexplored. In this study, we used the online computational tool CellMinerTM to explore the NCI-60 drug databases for compounds with anticancer activities correlating most closely with the mRNA expression of NQO1, a marker for NRF2 pathway activity. Among the >100,000 compounds analyzed, NSC84167, termed herein as NRF2 synthetic lethality compound-01 (NSLC01), was one of the top hits (r = 0.71, P < 0.001) and selected for functional characterization. NSLC01 selectively inhibited the viabilities of four out of seven conventional pancreatic cancer cell lines and induced dramatic apoptosis in the cells with high NRF2 activation. The selective anticancer activity of NSLC01 was further validated with a panel of nine low-passage pancreatic patient-derived cell lines, and a significant reverse correlation between log(IC50) of NSLC01 and NQO1 expression was confirmed (r = -0.5563, P = 0.024). Notably, screening of a panel of nine patient-derived xenografts (PDXs) revealed six PDXs with high NQO1/NRF2 activation, and NSLC01 dramatically inhibited the viabilities and induced apoptosis in ex vivo cultures of PDX tumors. Consistent with the ex vivo results, NSLC01 inhibited the tumor growth of two NRF2-activated PDX models in vivo (P < 0.01, n = 7-8) but had no effects on the NRF2-low counterpart. To characterize the mechanism of action, we employed a metabolomic isotope tracer assay that demonstrated that NSLC01-mediated inhibition of de novo synthesis of multiple amino acids, including asparagine and methionine. Importantly, we further found that NSLC01 suppresses the eEF2K/eEF2 translation elongation cascade and protein translation of asparagine synthetase. In summary, this study identified a novel compound that selectively targets protein translation and induces synthetic lethal effects in NRF2-activated pancreatic cancers.


Assuntos
Antineoplásicos/farmacologia , Asparagina/biossíntese , Aspartato-Amônia Ligase/metabolismo , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase do Fator 2 de Elongação/metabolismo , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , NAD(P)H Desidrogenase (Quinona)/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
JCI Insight ; 6(17)2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237033

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) tumors are characterized by a desmoplastic reaction resulting in dense deposition of collagen that is known to promote cancer progression. A central mediator of protumorigenic collagen signaling is the receptor tyrosine kinase discoid domain receptor 1 (DDR1). DDR1 is a critical driver of a mesenchymal and invasive cancer cell PDAC phenotype. Previous studies have demonstrated that genetic or pharmacologic inhibition of DDR1 reduces PDAC tumorigenesis and metastasis. Here, we investigated whether DDR1 signaling has cancer cell nonautonomous effects that promote PDAC progression and metastasis. We demonstrate that collagen-induced DDR1 activation in cancer cells is a major stimulus for CXCL5 production, resulting in the recruitment of tumor-associated neutrophils (TANs), the formation of neutrophil extracellular traps (NETs), and subsequent cancer cell invasion and metastasis. Moreover, we have identified that collagen-induced CXCL5 production was mediated by a DDR1/PKCθ/SYK/NF-κB signaling cascade. Together, these results highlight the critical contribution of the collagen I-DDR1 interaction in the formation of an immune microenvironment that promotes PDAC metastasis.


Assuntos
Carcinoma Ductal Pancreático/genética , Receptor com Domínio Discoidina 1/genética , Armadilhas Extracelulares/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Experimentais , Neutrófilos/patologia , Neoplasias Pancreáticas/genética , Animais , Carcinogênese , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/secundário , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , DNA de Neoplasias/genética , Receptor com Domínio Discoidina 1/biossíntese , Armadilhas Extracelulares/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Metástase Neoplásica , Neutrófilos/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Microambiente Tumoral
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