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1.
Mater Sci Eng C Mater Biol Appl ; 130: 112437, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34702522

RESUMO

Mimicking hierarchical porous architecture of bone has been considered as a valid approach to promote bone regeneration. In this study, hierarchical porous ß-tricalcium phosphate (ß-TCP) scaffolds were constructed by combining digital light processing (DLP) printing technique and in situ growth crystal process. Macro/micro hierarchical scaffolds with designed macro pores for facilitating the ingrowth of bone tissue were fabricated by DLP printing. Three types of micro/nano surface topography were obtained by in situ growth crystal process to regulate stem cells behavior. The attachment and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs) were strongly dependent on the surface roughness and the specific surface area. The micro/nano surface topography distinctly facilitated the differentiation of rBMSCs by targeting MAPK, STAT and AKT signaling pathways, in which the sodium hydroxide treatment group showed the highest promoting effect. Furthermore, in vivo results of skull defect repair model of rats indicated that hierarchical scaffolds with micro/nano topographies exhibited appealing bone regeneration capacity. The hierarchical porous bioceramic scaffolds constructed by integrating structural design and physical stimulation of the external surface topography have great potential for rapid bone repair via modulation of microenvironmental regulatory pathways at the bone defect site.


Assuntos
Osteogênese , Tecidos Suporte , Animais , Regeneração Óssea , Diferenciação Celular , Porosidade , Ratos , Crânio
2.
Int J Biol Macromol ; 188: 72-81, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34364938

RESUMO

The extrusion 3D printing of hydrogels has evolved as a promising approach that can be applied for specific tissue repair. However, the printing process of hydrogel scaffolds with high shape fidelity is inseparable from the complex crosslinking strategy, which significantly increases the difficulty and complexity of printing. The aim of this study was to develop a printable hydrogel that can extrude at room temperature and print scaffolds with high shape fidelity without any auxiliary crosslinking during the printing process. To this end, a novel formulation consisting of a Laponite suspension with a high solid concentration and a gelatine methacrylate (GelMA) nanocomposite hydrogel was developed. A homogeneously dispersed high-concentration (up to 20% w/v) Laponite suspension was obtained by stirring at 0 °C. The addition of Laponite with high concentration improved the rheological properties, the degradation stability, and the mechanical strength of the hydrogel. The formulation of 15% (w/v) GelMA and 8% (w/v) Laponite nanocomposite hydrogel exhibited desirable printability and biocompatibility. The GelMA/Laponite hydrogels significantly promoted bone marrow mesenchymal stem cell (BMSC) proliferation and osteogenic differentiation. Both desirable printability under mild conditions and cyto-compatibility enable composite hydrogel a potential candidate as biomaterial inks to be applied for bone tissue regeneration.

3.
Emerg Microbes Infect ; 10(1): 1555-1573, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34304724

RESUMO

To curb the pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), multiple platforms have been employed toward a safe and highly effective vaccine. Here, we develop a novel cell-based vaccine candidate, namely K562-S, by utilizing human cell K562 as a cellular carrier to display Spike (S) protein of SARS-CoV-2 on the membrane. Analogous to the traditional inactivated vaccine, K562-S cells can be propagated to a large scale by culturing and completely lose their viability after exposure to X-ray irradiation or formalin. We in turn demonstrated high immunogenicity of formalin-inactivated K562-S vaccine in both mouse and non-human primates and its protective efficacy in mice. In mice, immunization with inactivated K562-S vaccines can elicit potent neutralizing antibody (nAb) responses persisting longer than 5 months. We consequently showed in a hACE2 mouse model of SARS-CoV-2 infection that a two-shot vaccination with adjuvanted K562-S rendered greater than 3 log reduction in viral lung load and concomitant ameliorated lung pathology. Of importance, the administration of the same regimen in non-human primates was able to induce a neutralizing antibody titer averaging three-fold higher relative to human convalescent serum. These results together support the promise of K562-based, S-protein-expressing vaccines as a novel vaccination approach against SARS-CoV-2. Importantly, with a powerful capacity to carry external genes for cell-based vectors, this platform could rapidly generate two- and multiple-valent vaccines by incorporating SARS-CoV-2 mutants, SARS-CoV, or MERS-CoV.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Imunogenicidade da Vacina , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/imunologia , Animais , Animais Geneticamente Modificados , Vacinas contra COVID-19/administração & dosagem , Feminino , Células HEK293 , Humanos , Células K562 , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Primatas , Organismos Livres de Patógenos Específicos , Glicoproteína da Espícula de Coronavírus/administração & dosagem , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação/métodos , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
4.
Hum Vaccin Immunother ; 17(6): 1578-1585, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-33606578

RESUMO

Vaccinia virus was used to prevent smallpox. After the World Health Organization declared smallpox extinct, vaccinia virus has been explored for the development of vaccines against a variety of infectious diseases. It also finds a new place in oncolytic therapy. Here we provide a brief review of the history, current status, and future prospect of vaccinia virus-based vaccine and oncolytic virus. New advancements, including a single vaccine targeting multiple viruses, strategies of arming vaccinia viruses to enhance anti-tumor activity, the promise and challenge of combining vaccinia-based virotherapy with immunotherapy, are discussed as special focus.


Assuntos
Doenças Transmissíveis , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Imunoterapia , Vírus Vaccinia
5.
J Extracell Vesicles ; 9(1): 1778883, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32939233

RESUMO

Articular cartilage has limited self-regenerative capacity and the therapeutic methods for cartilage defects are still dissatisfactory in clinic. Recent studies showed that exosomes derived from mesenchymal stem cells promoted chondrogenesis by delivering bioactive substances to the recipient cells, indicating exosomes might be a novel method for repairing cartilage defect. Herein, we investigated the role and mechanism of human umbilical cord mesenchymal stem cells derived small extracellular vesicles (hUC-MSCs-sEVs) on cartilage regeneration. In vitro results showed that hUC-MSCs-sEVs promoted the migration, proliferation and differentiation of chondrocytes and human bone marrow mesenchymal stem cells (hBMSCs). MiRNA microarray showed that miR-23a-3p was the most highly expressed among the various miRNAs contained in hUC-MSCs-sEVs. Our data revealed that hUC-MSCs-sEVs promoted cartilage regeneration by transferring miR-23a-3p to suppress the level of PTEN and elevate expression of AKT. Moreover, we fabricated Gelatin methacrylate (Gelma)/nanoclay hydrogel (Gel-nano) for sustained release of sEVs, which was biocompatible and exhibited excellent mechanical property. In vivo results showed that hUC-MSCs-sEVs containing Gelma/nanoclay hydrogel (Gel-nano-sEVs) effectively promoted cartilage regeneration. These results indicated that Gel-nano-sEVs have a promising capacity to stimulate chondrogenesis and heal cartilage defects, and also provided valuable data for understanding the role and mechanism of hUC-MSCs-sEVs in cartilage regeneration.

6.
Ecotoxicol Environ Saf ; 204: 111060, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32768747

RESUMO

OBJECTIVE: Serratia sp. S2 is a wild strain with chromium resistance and reduction ability. Chromium(VI) metabolic-protein-coding gene ChrA and ChrT were cloned from Serratia sp. S2, and ligated with prokaryotic expression vectors pET-28a (+) and transformed into E. coli BL21 to construct ChrA, ChrT and ChrAT engineered bacteria. By studying the characteristics of Cr(VI) metabolism in engineered bacteria, the function and mechanism of the sole expression and coexpression of ChrA and ChrT genes were studied. METHODS: Using Serratia sp. S2 genome as template, ChrA and ChrT genes were amplified by PCR, and prokaryotic expression vectors was ligated to form the recombinant plasmid pET-28a (+)-ChrA, pET-28a (+)-ChrT and pET-28a (+)-ChrAT, and transformed into E. coli BL21 to construct ChrA, ChrT, ChrAT engineered bacteria. The growth curve, tolerance, and reduction of Cr(VI), the distribution of intracellular and extracellular Cr, activity of chromium reductase and intracellular oxidative stress in engineered bacteria were measured to explore the metabolic characteristics of Cr(VI) in ChrA, ChrT, ChrAT engineered bacteria. RESULTS: ChrA, ChrT and ChrAT engineered bacteria were successfully constructed by gene recombination technology. The tolerance to Cr(VI) was Serratia sp. S2 > ChrAT ≈ ChrA > ChrT > Control (P < 0.05), and the reduction ability to Cr(VI) was Serratia sp. S2 > ChrAT ≈ ChrT > ChrA (P < 0.05). The chromium distribution experiments confirmed that Cr(VI) and Cr(III) were the main valence states. Effect of electron donors on chromium reductase activity was NADPH > NADH > non-NAD(P)H (P < 0.05). The activity of chromium reductase increased significantly with NAD(P)H (P < 0.05). The Glutathione and NPSH (Non-protein Sulfhydryl) levels of ChrA, ChrAT engineered bacteria increased significantly (P < 0.05) under the condition of Cr(VI), but there was no significant difference in the indexes of ChrT engineered bacteria (P > 0.05). CONCLUSION: ChrAT engineered bacteria possesses resistance and reduction abilities of Cr(VI). ChrA protein endows the strain with the ability to resist Cr(VI). ChrT protein reduces Cr(VI) to Cr(III) by using NAD(P)H as electronic donor. The reduction process promotes the production of GSH, GSSG and NPSH to maintain the intracellular reduction state, which further improves the Cr(VI) tolerance and reduction ability of ChrAT engineered bacteria.


Assuntos
Proteínas de Bactérias/genética , Compostos de Cromo/metabolismo , Poluentes Ambientais/metabolismo , Genes Bacterianos , Proteínas de Membrana/genética , Microrganismos Geneticamente Modificados/genética , Serratia/genética , Biodegradação Ambiental , Escherichia coli/genética , Escherichia coli/metabolismo , Microrganismos Geneticamente Modificados/metabolismo , Modelos Teóricos , Oxirredução , Oxirredutases/metabolismo , Serratia/metabolismo
7.
J Glob Health ; 10(1): 011002, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32257174

RESUMO

Background: Recent outbreak of 2019-nCoV in Wuhan raised serious public health concerns. By February 15, 2020 in Wuhan, the total number of confirmed infection cases has reached 37 914, and the number of deaths has reached 1123, accounting for 56.9% of the total confirmed cases and 73.7% of the total deaths in China. People are eager to know when the epidemic will be completely controlled and when people's work and life will be on the right track. Method: In this study we analyzed the epidemic dynamics and trend of 2019-nCoV in Wuhan by using the data after the closure of Wuhan city till February 12, 2020 based on the SEIR modeling method. Results: The optimal parameters were estimated as R0 = 1.44 (interquartile range: 1.40-1.47), TI = 14 (interquartile range = 14-14) and TE = 3.0 (interquartile range = 2.8-3.1). Based on these parameters, the number of infected individuals in Wuhan city may reach the peak around February 19 at about 47 000 people. Once entering March, the epidemic would gradually decline, and end around the late March. It is worth noting that the above prediction is based on the assumption that the number of susceptible population N = 200 000 will not increase. If the epidemic situation is not properly controlled, the peak of infected number can be further increased and the peak time will be a little postponed. It was expected that the epidemic would subside in early March, and disappear gradually towards the late March. Conclusions: The epidemic situation of 2019-nCoV in Wuhan was effectively controlled after the closure of the city, and the disease transmission index also decreased significantly. It is expected that the peak of epidemic situation would be reached in late February and end in March.


Assuntos
Infecções por Coronavirus/epidemiologia , Coronavirus , Surtos de Doenças/prevenção & controle , Pneumonia Viral/epidemiologia , Betacoronavirus , COVID-19 , China/epidemiologia , Coronavirus/isolamento & purificação , Coronavirus/patogenicidade , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Epidemias , Monitoramento Epidemiológico , Humanos , Modelos Estatísticos , Mortalidade , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/virologia
8.
J Mech Behav Biomed Mater ; 104: 103673, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32174429

RESUMO

Functionally graded materials (FGMs) with porosity variation strategy mimicking natural bone are potential high-performance biomaterials for orthopedic implants. The architecture of FGM scaffold is critical to gain the favorable combination of mechanical and biological properties for osseointegration. In this study, four types of FGM scaffolds with different structures were prepared by selective laser melting (SLM) with Ti6Al4V as building material. All the scaffolds were hollow cylinders with different three-dimensional architectures and had gradient porosity resembling the graded-porous structure of human bone. Two unit cells (diamond and honeycomb-like unit cells) were used to construct the cellular structures. Solid support structures were embedded into the cellular structures to improve their mechanical performances. The physical characteristics, mechanical properties, and deformation behaviors of the scaffolds were compared systematically. All the as-built samples with porosities of ~52-67% exhibited a radial decreasing porosity from the inner layer to the outer layer, and their pore sizes ranged from ~420 to ~630 µm. The compression tests showed the Young's moduli of all the as-fabricated samples (~3.79-~10.99 GPa) were similar to that of cortical bone. The FGM structures built by honeycomb-like unit cells with supporting structure in outer layer exhibited highest yield strength, toughness and stable mechanical properties which is more appropriate to build orthopedic scaffolds for load-bearing application.


Assuntos
Lasers , Titânio , Ligas , Materiais Biocompatíveis , Humanos , Porosidade , Suporte de Carga
9.
Ecotoxicol Environ Saf ; 157: 417-423, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29655157

RESUMO

OBJECTIVE: To find an efficient chromium (VI) resistance system, with a highly efficient, economical, safe, and environmentally friendly chromium-removing strain, ChrA, ChrB, and ChrAB fragments of the chromium (VI) resistance gene in Serratia sp. S2 were cloned, and their prokaryotic expression vectors were constructed and transformed into E. coli BL21. The anti-chromium (VI) capacity and characteristics of engineered bacteria, role of ChrA and ChrB genes in the anti-chromium (VI) processes, and the mechanism of chromium metabolism, were explored. METHODS: The PCR technique was used to amplify ChrA, ChrB, and ChrAB genes from the Serratia sp. S2 genome. ChrA, ChrB, and ChrAB genes were connected to the prokaryotic expression vector pET-28a and transferred into E. coli BL21 for prokaryotic expression. Cr-absorption and Cr-efflux ability of the engineered strains were determined. The effects of respiratory inhibitors and oxygenated anions on Cr-efflux of ChrA and ChrB engineered strains were explored. RESULTS: ChrA, ChrB, and ChrAB engineered strains were constructed successfully; there was no significant difference between the control strain and the ChrB engineered strain for Cr-metabolism (P > 0.05). Cr-absorption and Cr-efflux of ChrA and ChrAB engineered strains were significantly stronger than the control strain (P < 0.05). Oxyanions (sulfate and molybdate) and inhibitors (valinomycin and CN-) could significantly inhibit the Cr-efflux capacities of ChrA and ChrAB engineered strains (P < 0.05), while NADPH could significantly promote such capacities (P < 0.05). CONCLUSION: The Cr-transporter, encoded by ChrA gene, confer the ability to pump out intracellular Cr on ChrA and ChrAB engineered strains. The ChrB gene plays a positive regulatory role in ChrA gene regulation. The Cr-metabolism ability of the ChrAB engineered strain is stronger than the ChrA engineered strain. ChrA and ChrAB genes in the Cr-resistance system may involve a variety of mechanisms, such as sulfate ion channel and respiratory chain electron transfer.


Assuntos
Proteínas de Bactérias/genética , Cromo/farmacologia , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana/genética , Serratia/genética , Clonagem Molecular , DNA Bacteriano/genética , Farmacorresistência Bacteriana/genética , Escherichia coli , Microrganismos Geneticamente Modificados/genética , Análise de Sequência de DNA , Serratia/efeitos dos fármacos
10.
Appl Biochem Biotechnol ; 185(1): 140-152, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29098559

RESUMO

This study is to investigate the genome sequence of Serratia sp. S2. The genomic DNA of Serratia sp. S2 was extracted and the sequencing library was constructed. The sequencing was carried out by Illumina 2000 and complete genomic sequences were obtained. Gene function annotation and bioinformatics analysis were performed by comparing with the known databases. The genome size of Serratia sp. S2 was 5,604,115 bp and the G+C content was 57.61%. There were 5373 protein coding genes, and 3732, 3614, and 3942 genes were respectively annotated into the GO, KEGG, and COG databases. There were 12 genes related to chromium metabolism in the Serratia sp. S2 genome. The whole genome sequence of Serratia sp. S2 is submitted to the GenBank database with gene accession number of LNRP00000000. Our findings may provide theoretical basis for the subsequent development of new biotechnology to repair environmental chromium pollution.


Assuntos
Cromo/metabolismo , Bases de Dados de Ácidos Nucleicos , Genes Bacterianos , Anotação de Sequência Molecular , Serratia/genética , Serratia/metabolismo
11.
Exp Ther Med ; 14(3): 2361-2366, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28962168

RESUMO

In order to remediate the metal-contaminated soil and water ecosystems with microorganisms, an engineered strain, which contained the chromate reductase ChrT gene from Serratia sp. S2, was studied in detail for its Cr (VI) reduction efficiency, optimal culture condition and chromate reductase activity. Results demonstrated that the engineered strain had a high Cr (VI) reduction rate of up to 40% at a concentration of 50 mg/l after being cultured for 48 h. Additionally, the optimal culture conditions were pH 7.0 and 37°C. Furthermore, the carbon sources and metal cations exhibited significant effects on the Cr (VI) reduction rate of the engineered bacterium. Sodium lactate, sodium acetate, Cu2+, Co2+ and Pb2+ were positively correlated with the reduction rate. Chromate reductase was soluble and presented in the cytoplasm. Furthermore, the enzymatic activity with nicotinamide adenine dinucleotide phosphate, which was as an electron donor, reached 14.83 U/mg.

12.
Nan Fang Yi Ke Da Xue Xue Bao ; 37(10): 1290-1295, 2017 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-29070456

RESUMO

OBJECTIVE: To construct a genetically engineered Escherichia coli expressing chromate (Cr) ion transporter ChrA and test its Cr resistance capacity. METHODS: ChrA gene was cloned by PCR from the DNA template of Serratia sp. S2 and linked with the prokaryotic vector pET-28a (+). The recombinant vector was transformed into E.coli BL21 (DE3) cells for expression of ChrA protein. Cr (VI) risistance and Cr (VI) uptake and efflux of the engineered bacteria were tested, and the effects of Cr loading time, oxyanions (ulfate, molybdate, vanadate, tungstate), and respiratory inhibitors (valinomycin, CN-, oligomycin, and NADH) on Cr (VI) efflux were examined to analyze the pathway of Cr (VI) transport by ChrA protein. RESULTS: The engineered E. coil strain was successfully constructed. Experiments using cell suspensions showed a lowered Cr2O72- uptake but an increased efflux capacity of ChrA-engineered bacteria compared with the control strain (P<0.05). The engineered E. coil cells in exponential growth incubated for 30 min in the presence of 50 mg/L Cr2O72- showed a total displacement of Cr (VI) of 20% after resuspension in PBS at 10 min, but chromate efflux decreased subsequently as the incubation time extended. Oxyanions sulfate and molybdate significantly inhibited chromate efflux in the engineered bacteria (P<0.05), whereas tungstate and vanadate did not obviously affect chromate efflux; chromate efflux was significantly inhibited by K+ ionophore valinomycin and CN-, enhanced by NADH (P<0.05), but not affected by oligomycin, suggesting the role of chromate transporter ChrA as a chemiosmotic pump that extrudes chromate using the proton-motive force. CONCLUSION: ChrA can efficiently transport chromate ions from the cytoplasm to enhance chromate resistance of the genetically engineered E. coli.


Assuntos
Proteínas de Bactérias/metabolismo , Cromatos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Erros Inatos do Metabolismo , Proteínas de Bactérias/genética , Cromo , Escherichia coli/metabolismo , Proteínas de Membrana/genética , Microrganismos Geneticamente Modificados , Serratia/genética
13.
Am J Chin Med ; 45(7): 1327-1344, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28922926

RESUMO

Alzheimer's disease (AD) is associated with the unprecedented aging tendency in our world population and has become a significant health issue. The use of Traditional Chinese Medicine to treat AD has been increasing in recent years. The objective of this meta-analysis is to evaluate the effectiveness of combining acupuncture with herbal medicine to treat AD. Randomized controlled trials (RCTs) of acupuncture plus herbals versus treatment with western drugs for AD were retrieved from 11 databases. The data were extracted by two authors; dichotomous data were expressed as odds ratio (ORs) and 95% confidence intervals (CIs), while continuous data were calculated by mean differences (MDs) with 95% CIs. Although the combined analysis of the score of Activity of Daily Life (ADL) scale MD was [Formula: see text]3.59 (95% CI [Formula: see text]7.18-0.01, [Formula: see text]), which indicates there was no statistically significant difference between the two treatments at reducing the ADL scale score, the pooled results of 12 trials indicated that acupuncture plus Chinese herbal medicine was better than western drugs at improving the effectiveness rate (OR 2.24, 95% CI 1.40-3.56), the combined evidence of 11 articles showed that acupuncture plus Chinese herbal medicine was more effective than western drugs at improving the scores for the Mini Mental State Examination (MMSE) scale (2.10, 95% CI 0.69-3.51, [Formula: see text]) and the traditional Chinese medicine symptom (MD 5.07, 95% CI 3.90-6.25, [Formula: see text]). From the current research results, acupuncture plus herbal medicine may have advantages over western drugs for treating AD. Nevertheless, well-designed RCTs with a larger sample size are required in the future.


Assuntos
Terapia por Acupuntura , Doença de Alzheimer/terapia , Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Terapia Combinada , Bases de Dados Bibliográficas , Feminino , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Retrovirology ; 14(1): 16, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28270144

RESUMO

BACKGROUND: Prototype foamy virus (PFV) is a member of the Spumaretrovirinae subfamily of retroviruses, which maintains lifelong latent infection while being nonpathogenic to their natural hosts. Autophagy is a cell-programmed mechanism that plays a pivotal role in controlling homeostasis and defense against exotic pathogens. However, whether autophagy is the mechanism for host defense in PFV infection has not been investigated. FINDINGS: Our results revealed that PFV infection induced the accumulation of autophagosomes and triggered complete autophagic flux in BHK-21 cells. PFV infection also altered endoplasmic reticulum (ER) homeostasis. The PERK, IRE1 and ATF6 pathways, all of which are components of the ER stress-related unfolded protein response (UPR), were activated in PFV-infected cells. In addition, accelerating autophagy suppressed PFV replication, and inhibition of autophagy promoted viral replication. CONCLUSIONS: Our data indicate that PFV infection can induce complete autophagy through activating the ER stress-related UPR pathway in BHK-21 cells. In turn, autophagy negatively regulates PFV replication.


Assuntos
Autofagia , Estresse do Retículo Endoplasmático , Interações Hospedeiro-Patógeno , Spumavirus/imunologia , Spumavirus/fisiologia , Resposta a Proteínas não Dobradas , Animais , Linhagem Celular , Cricetinae , Replicação Viral
15.
AIDS Res Hum Retroviruses ; 33(5): 452-464, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27750433

RESUMO

Human foamy virus (HFV) is a complex and unique retrovirus with the longest genomes among retroviruses that are used as vectors for gene therapy. Long non-coding RNAs (lncRNAs) are regarded as key regulators that are involved in diverse biological processes during viral infection. However, the role of lncRNAs in HFV infection remains unknown. In this study, we utilized next-generation sequencing to first characterize lncRNAs in 293T cells after HFV infection, evaluating length distribution, exon number distribution, volcano picture, and lncRNA class distribution. We identified 11,336 lncRNAs (4,729 upregulated lncRNAs and 6,588 downregulated lncRNAs) and 61,367 mRNAs (30,133 upregulated mRNAs and 31,220 downregulated mRNAs), which were differentially expressed in the HFV-infected 293T cells. Subsequently, six differentially expressed lncRNAs characterized using RNA-seq were confirmed by quantitative real-time polymerase chain reaction assays. Interestingly, Gene Ontology (GO)/Gene Ontology Tree Machine (GOTM) and Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analyses indicated that positive regulation of interleukin 8 (IL8) production and cytokine-cytokine receptor interaction might be involved in the functional enrichment of lncRNAs. Moreover, cis-acting and trans-acting regulatory networks show that NR_028036 may target the fas gene in a cis-acting manner and that ENST00000354838 may target the IL18 gene in a trans-acting manner. Overall, these results not only provide novel insights into the relationship between HFV and lncRNAs in the host response to infection but also have implications for the future wider application of HFV as a vector.


Assuntos
Interações Hospedeiro-Patógeno , RNA Longo não Codificante/análise , Vírus Espumoso dos Símios/crescimento & desenvolvimento , Células HEK293 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , RNA Longo não Codificante/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA
16.
Viruses ; 7(4): 1668-84, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25848801

RESUMO

Prototype foamy virus (PFV) is a member of the unconventional and nonpathogenic retroviruses. PFV causes lifelong chronic infections, which are partially attributable to a number of host cell factors that restrict viral replication. Herein, we identified human p53-induced RING-H2 protein (Pirh2) as a novel inhibitor of prototype foamy virus. Overexpression of Pirh2 decreased the replication of PFV, whereas knockdown of Pirh2 with specific siRNA increased PFV replication. Dual-luciferase assays and coimmunoprecipitation demonstrated that Pirh2 negatively influences the Tas-dependent transcriptional activation of the PFV long terminal repeat (LTR) and internal promoter (IP) by interacting with the transactivator Tas and down-regulating its expression. In addition, the viral inhibitory function of Pirh2 is N-terminal and RING domain dependent. Together, these results indicated that Pirh2 suppresses PFV replication by negatively impacting its transactivator Tas and the transcription of two viral promoters, which may contribute to the latency of PFV infection.


Assuntos
Vírus Espumoso dos Símios/imunologia , Vírus Espumoso dos Símios/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Latência Viral , Replicação Viral/efeitos dos fármacos , Linhagem Celular , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Humanos , Transcrição Genética/efeitos dos fármacos
17.
Biochem Biophys Res Commun ; 458(4): 810-5, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25701784

RESUMO

Enterovirus 71 (EV71) is a neurotropic virus that causes hand, foot and mouth disease (HFMD), occasionally leading to death. As a member of the RAS association domain family (RASSFs), RASSF4 plays important roles in cell death, tumor development and signal transduction. However, little is known about the relationship between RASSF4 and EV71. Our study reveals for the first time that RASSF4 promotes EV71 replication and then accelerates AKT phosphorylation inhibition in EV71-infected 293T cells, suggesting that RASSF4 may be a potential new target for designing therapeutic measures to prevent and control EV71 infection.


Assuntos
Enterovirus Humano A/fisiologia , Doença de Mão, Pé e Boca/virologia , Interações Hospedeiro-Patógeno , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Replicação Viral , Apoptose , Linhagem Celular , Doença de Mão, Pé e Boca/fisiopatologia , Humanos , Fosforilação
18.
AIDS Res Hum Retroviruses ; 31(2): 183-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25531134

RESUMO

RNA interference has shown great potential for the treatment of HIV-1. Vectors derived from prototype foamy viruses (PFVs) with a nonpathogenic nature are very promising gene transfer vehicles in anti-HIV gene therapy. In this article, three short hairpin RNAs (shRNAs) targeting the conserved regions of the HIV-1NL4-3 5' long terminal repeat (LTR) were first designed. We then constructed novel recombinant PFV vector plasmids, p▵Φ-H1-shRNAs, expressing these shRNAs under the control of the H1 RNA promoter. To detect the efficacy of these ▵Φ-H1-shRNAs for the inhibition of HIV-1 replication, we performed a dual-luciferase reporter assay, RT-qPCR, ELISA, western blotting, and a lactate dehydrogenase (LDH) assay by transient transfection in 293T cells. The results suggest that these novel shRNAs driven by PFV vectors inhibit HIV-1 replication efficiently without cytotoxicity, with shRNA3 being the most effective. In addition, we analyzed the shRNA target sites in the 5' LTR of HIV-1 strains other than HIV-1NL4-3 and found that these shRNAs may possibly inhibit other HIV-1 strains.


Assuntos
Fármacos Anti-HIV/metabolismo , Portadores de Fármacos , Terapia Genética/métodos , HIV-1/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Linfócitos T/fisiologia , Linfócitos T/virologia , Produtos Biológicos/metabolismo , Western Blotting , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Perfilação da Expressão Gênica , Vetores Genéticos , HIV-1/genética , Humanos , L-Lactato Desidrogenase/análise , Regiões Promotoras Genéticas , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Spumavirus/genética
19.
PLoS One ; 9(11): e112163, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25386745

RESUMO

BACKGROUND: Schistosomiasis is a major health problem in tropical and sub-tropical areas caused by species of trematode belonging to the genus Schistosoma. The treatment and control of this disease has been relying on the use of a single drug praziquantel. However, the drug resistance concern urged the development of new drugs against schistosoma. Here, we report our systematic biological evaluation of DW-3-15, a new lead compound developed based on our conjugation design rationale as an effective anti-schistosomal agent. METHODOLOGY/PRINCIPAL FINDINGS: The antischistosomal activity of DW-3-15 was systematically evaluated in S. japonicum infected mouse model for its stage-sensitivity and dose response. The results revealed that DW-3-15 exhibited 60-85% worm reduction rate against different development stage of worm. Scanning electron microscopy (SEM) observation indicated that DW-3-15 may damage to the tegument of male schistosomes. CONCLUSIONS/SIGNIFICANCE: Our results demonstrated that DW-3-15 showed potent anti-schistosomal activities in vivo. The results strongly support our conjugation design strategy of artemisinin analogs and further development of DW-3-15 as a new lead compound as anti-schistosomal agent.


Assuntos
Artemisininas/uso terapêutico , Praziquantel/uso terapêutico , Esquistossomose Japônica/tratamento farmacológico , Esquistossomicidas/uso terapêutico , Administração Oral , Animais , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos ICR
20.
Bioorg Med Chem Lett ; 24(17): 4223-6, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25127102

RESUMO

A series of chiral praziquantel analogues were synthesized and evaluated against Schistosoma japonicum both in vitro and in vivo. All compounds exhibited low to considerable good activity in vivo. Remarkably, worm reduction rate of R-3 was 60.0% at a single oral dose of 200mg/kg against juvenile stage of Schistosoma japonicum. The target compounds displayed in vivo antischistosomal activity against both Schistosoma japonicum and Schistosoma mansoni. Furthermore, all R-isomers displayed stronger antischistosomal activity than S-isomers in vivo, indicating R-isomers were the active enantiomers, while S-isomers were less active ones. This structure activity relationship (SAR) could have important implications in further drug development for schistosomiasis.


Assuntos
Praziquantel/análogos & derivados , Praziquantel/farmacologia , Schistosoma japonicum/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Estrutura Molecular , Praziquantel/síntese química , Praziquantel/química , Schistosoma japonicum/crescimento & desenvolvimento , Schistosoma mansoni/efeitos dos fármacos , Relação Estrutura-Atividade
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