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BACKGROUND & AIMS: HBV consists of 9 major genotypes (A to I), 1 minor strain (designated J) and multiple subtypes, which may be associated with different clinical characteristics. As only cell lines expressing genotype D3 have been established, herein, we aimed to establish stable cell lines producing high-titer cell culture-generated HBV (HBVcc) of different genotypes and to explore their infectivity, virological features and responses to treatment. METHODS: Stable cell lines producing high titers of HBV genotype A2, B2, C1, E, F1b and H were generated by transfecting plasmids containing a replication-competent 1.3x length HBV genome and an antibiotic marker into HepG2 cells that can support HBV replication. Clones with the highest levels of HBV DNA and/or HBeAg were selected and expanded for large-scale purification of HBVcc. HBVcc of different genotypes were tested in cells and a humanized chimeric mouse model. RESULTS: HBVcc genotypes were infectious in mouse-passaged primary human hepatocytes (PXB cells) and responded differently to human interferon (IFN)-α with variable kinetics of reduction in HBV DNA, HBeAg and HBsAg. HBVcc of all genotypes were infectious in humanized chimeric mice but with variable kinetics of viremia and viral antigen production. Treatment of infected mice with human IFN-α resulted in modest and variable reductions of viremia and viral antigenemia. HBVcc passaged in humanized chimeric mice (HBVmp) infected PXB cells much more efficiently than that of the original HBVcc viral stock. CONCLUSIONS: Herein, we generated stable cell lines producing HBV of various genotypes that are infectious in vitro and in vivo. We observe genotype-associated variations in viral antigen production, infection kinetics and responses to human IFN-α treatment in these models. LAY SUMMARY: Stable cell lines producing high-titer cell culture-generated hepatitis B virus (HBV) of various genotypes were established. HBV genotypes showed stable infectivity in both in vitro and in vivo models, which are valuable tools for antiviral development.
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Genótipo , Hepatite B/complicações , Animais , Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/estatística & dados numéricos , Modelos Animais de Doenças , Hepatite B/genética , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/patogenicidade , CamundongosRESUMO
Cellular receptors play an important role in entry and cell to cell spread of morbillivirus infections. The cells expressing SLAM and Nectin-4 have been used for successful and efficient isolation of canine distemper virus (CDV) in high titre. There are several methods for generation of cells expressing receptor molecules. Here, we have used a comparatively cheaper and easily available method, pcDNA 3.1 (+) for engineering Vero cells to express SLAM gene of goat, sheep and dog origin (Vero/Goat/SLAM (VGS), Vero/Sheep/SLAM (VSS) and Vero/Dog/SLAM (VDS), respectively). The generated cell lines were then compared to test their efficacy to support CDV replication. CDV could be grown in high titre in the cells expressing SLAM and a difference of log two could be recorded in virus titre between VDS and native Vero cells. Also, CDV could be grown in a higher titre in VDS as compared to VGS and VSS. The finding of this study supports the preferential use of SLAM expressing cells over the native Vero cells by CDV. Further, the higher titre of CDV in cells expressing dog-SLAM as compared to the cells expressing SLAM of non-CDV hosts (i.e. goat and sheep) points towards the preferential use of dog SLAM by the CDV and may be a plausible reason for differential susceptibility of small ruminants and Canines to CDV.
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Vírus da Cinomose Canina , Cinomose , Animais , Antígenos CD , Linhagem Celular , Chlorocebus aethiops , Vírus da Cinomose Canina/genética , Cães , Cabras , Ativação Linfocitária , Ovinos , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária , Células VeroRESUMO
Inhaled Aspergillus fumigatus spores can be internalized by alveolar type II cells. Cell lines stably expressing fluorescently labeled components of endocytic pathway enable investigations of intracellular organization during conidia internalization and measurement of the process kinetics. The goal of this report was to evaluate the methodological appliance of cell lines for studying fungal conidia internalization. We have generated A549 cell lines stably expressing fluorescently labeled actin (LifeAct-mRuby2) and late endosomal protein (LAMP1-NeonGreen) following an evaluation of cell-pathogen interactions in live and fixed cells. Our data show that the LAMP1-NeonGreen cell line can be used to visualize conidia co-localization with LAMP1 in live and fixed cells. However, caution is necessary when using LifeAct-mRuby2-cell lines as it may affect the conidia internalization dynamics.
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Células Epiteliais Alveolares , Aspergilose/microbiologia , Aspergillus fumigatus , Interações Hospedeiro-Patógeno , Células A549 , Células Epiteliais Alveolares/microbiologia , Células Epiteliais Alveolares/ultraestrutura , Aspergillus fumigatus/patogenicidade , Aspergillus fumigatus/fisiologia , Aspergillus fumigatus/ultraestrutura , Proteínas de Fluorescência Verde/metabolismo , Humanos , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Imagem Óptica , Fagocitose , Esporos Fúngicos/metabolismoRESUMO
Human tumor cell lines, especially those with complete data and follow-up, are important tools in tumor biological studies. Clear cell renal cell cancer (ccRCC) is not sensitive to radiotherapy or chemotherapy, and treatment of patients with distant metastasis relies on targeted therapy. Here, we report the establishment of seven new ccRCC stable cell lines that were continuously cultured for more than 20 generations among 81 cases of renal cell cancer. Moreover, gene expression and methylation in the established cell lines, in those that had a finite in vitro life span of less than 10 generations, and in cells that originated from the same culture at different generations were profiled using microarrays. Genes including SLC34A2, SEPP1, SULT1C4 and others were differentially expressed in established cell lines and finite cell lines, and changes in their expression might be caused by methylation or demethylation. The expression level of SLC34A2 was related not only to the life span in vitro culture but also to tumor size. Additionally, six of the seven new ccRCC cell lines had VHL deletions or termination mutations. So in addition to the establishment of seven new ccRCC cell lines with complete clinical data, we conclude that genes such as SLC34A2 and VHL play key roles in the continuous in vitro growth and development of ccRCC.
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Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Metilação , Pessoa de Meia-Idade , Mutação/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIb/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genéticaRESUMO
Seasonal and highly infectious strains of the influenza A and influenza B viruses cause millions of cases of severe complications in elderly people, children, and patients with immune diseases each year. Immunoglobulin A (IgA), which is an active component of humoral immunity, can prevent the spread of the virus in the upper respiratory tract. The preparation and study of the properties of recombinant virus-specific IgA could be an important approach to finding new means of preventing and treating influenza. Based on CHO DG44 cells, we developed stable monoclonal cell lines that produce monomeric and dimeric antibodies FI6-IgA1 and FI6-IgA2m1 to hemagglutinin (HA) of the influenza A virus. When studying the productivity, growth, and stability of the obtained clones, we found that the dimeric form of antibodies of IgA1 isotype is superior to other forms. The dimeric form of IgA antibodies plays a key role in mucosal immunity. Recognizing the prospects of using dimeric IgA as prophylactic and therapeutic mucosal drugs for viral infections, we studied their virus-neutralizing and antiviral activities on MDCK cell culture and compared them with the antibodies of the IgG1 isotype. This study presents the data on antiviral and virus-neutralizing activities of the FI6-IgA1 dimers to seasonal and highly infectious strains of influenza A virus.
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Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/farmacologia , Antivirais/farmacologia , Imunoglobulina A/farmacologia , Imunoglobulina G/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/genética , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/genética , Antivirais/química , Antivirais/metabolismo , Células CHO , Cricetulus , Cães , Expressão Gênica , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Imunoglobulina A/biossíntese , Imunoglobulina A/genética , Imunoglobulina G/biossíntese , Imunoglobulina G/genética , Vírus da Influenza A/crescimento & desenvolvimento , Vírus da Influenza A/imunologia , Células Madin Darby de Rim Canino , Testes de Neutralização , Multimerização Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologiaRESUMO
(1) Recombinant protein production in mammalian cells is either based on transient transfection processes, often inefficient and underlying high batch-to-batch variability, or on laborious generation of stable cell lines. Alternatively, BacMam, a transduction process using the baculovirus, can be employed. (2) Six transfecting agents were compared to baculovirus transduction in terms of transient and stable protein expression characteristics of the model protein ACE2-eGFP using HEK293-6E, CHO-K1, and Vero cell lines. Furthermore, process optimization such as expression enhancement using sodium butyrate and TSA or baculovirus purification was assessed. (3) Baculovirus transduction efficiency was superior to all transfection agents for all cell lines. Transduced protein expression was moderate, but an 18-fold expression increase was achieved using the enhancer sodium butyrate. Ultracentrifugation of baculovirus from a 3.5 L bioreactor significantly improved the transduction efficiency and protein expression. Stable cell lines were obtained with each baculovirus transduction, yet stable cell line generation after transfection was highly unreliable. (4) This study demonstrated the superiority of the BacMam platform to standard transfections. The baculovirus efficiently transduced an array of cell lines both transiently and stably and achieved the highest efficiency for all tested cell lines. The feasibility of the scale-up of baculovirus production was demonstrated and the possibility of baculovirus purification was successfully explored.
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Baculoviridae , Vetores Genéticos , Animais , Humanos , Ácido Butírico , Células HEK293 , Vetores Genéticos/genética , Baculoviridae/genética , Baculoviridae/metabolismo , Plasmídeos/genética , MamíferosRESUMO
GABAA receptors (γ-aminobutyric acid-gated receptors type A; GABAARs), the major structural and functional postsynaptic components of inhibitory synapses in the mammalian brain, belong to a family of GABA-gated Cl-/HCO3 - ion channels. They are assembled as heteropentamers from a family of subunits including: α (1-6), ß(1-3), γ(1-3), δ, ε, π, θ and ρ(1-3). GABAARs together with the postsynaptic adhesion protein Neuroligin 2 (NL2) and many other pre- and post-synaptic proteins guide the initiation and functional maturation of inhibitory GABAergic synapses. This study examined how GABAARs and NL2 interact with each other to initiate the formation of synapses. Two functionally distinct GABAAR subtypes, the synaptic type α2ß2γ2-GABAARs versus extrasynaptic type α4ß3δ-GABAARs were expressed in HEK293 cells alone or together with NL2 and co-cultured with striatal GABAergic medium spiny neurons to enable innervation of HEK293 cells by GABAergic axons. When expressed alone, only the synaptic α2ß2γ2-GABAARs induced innervation of HEK293 cells. However, when GABAARs were co-expressed with NL2, the effect on synapse formation exceeded the individual effects of these proteins indicating a synergistic interaction, with α2ß2γ2-GABAAR/NL2 showing a significantly greater synaptogenic activity than α4ß3δ-GABAAR/NL2 or NL2 alone. To investigate the molecular basis of this interaction, different combinations of GABAAR subunits and NL2 were co-expressed, and the degree of innervation and synaptic activity assessed, revealing a key role of the γ2 subunit. In biochemical assays, the interaction between NL2 and α2ß2γ2-GABAAR was established and mapped to the large intracellular domain of the γ2 subunit.
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BACKGROUND: The biopharmaceutical industry is significantly growing worldwide, and the Chinese hamster ovary (CHO) cells are used as a main expression host for the production of recombinant monoclonal antibodies. Various metabolic engineering approaches have been investigated to generate cell lines with improved metabolic characteristics for increasing longevity and mAb production. A novel cell culture method based on the 2-stage selection makes it possible to develop a stable cell line with high-quality mAb production. RESULTS: We have constructed several design options of mammalian expression vectors for the high production of recombinant human IgG antibodies. Versions for bipromoter and bicistronic expression plasmids different in promoter orientation and cistron arrangements were generated. The aim of the work presented here was to assess a high-throughput mAb production system that integrates the advantages of high-efficiency cloning and stable cell clones to stage strategy selection reducing the time and effort required to express therapeutic monoclonal mAbs. Development of a stable cell line using bicistronic construct with EMCV IRES-long link gave an advantage in high mAb expression and long-term stability. Two-stage selection strategies allowed the elimination of low-producer clones by using metabolic level intensity to estimate the IgG production in the early steps of selection. The practical application of the new method allows to reduce time and costs during stable cell line development.
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BACKGROUND: The use of encapsulated cells for the in vivo delivery of biotherapeutics is a promising new technology to potentiate the effectiveness of cell-based therapies for veterinary and human application. One use of the technology is to locally activate chemotherapeutics to their short-lived highly active forms. We have previously shown that a stable clone of HEK293 cells overexpressing a cytochrome P450 enzyme that has been encapsulated in immunoprotective cellulose sulphate beads can be implanted near solid tumours in order to activate oxazaphosphorines such as ifosfamide and cyclophosphamide to the tumour-killing metabolite phosphoramide mustard. The efficacy of this approach has been shown in animal models as well as in human and canine clinical trials. In these previous studies, the oxazaphosphorine was only given twice. An analysis of the Kaplan-Meier plots of the results of the clinical trials suggest that repeated dosing might result in a significant clinical benefit. AIMS: In this study, we aimed to (i) demonstrate the stable long-term expression of cytochrome P450 from a characterized, transfected cell clone, as well as (ii) demonstrate that one implanted dose of these encapsulated cytochrome P450-expressing cells is capable of activating multiple doses of ifosfamide in animal models. METHODOLOGY: We initially used cell and molecular methods to show cell line stability over multiple passages, as well as chemical and biological function in vitro. This was followed by a demonstration that encapsulated HEK293 cells are capable of activating multiple doses of ifosfamide in a mouse model of pancreatic cancer without being killed by the chemotherapeutic. CONCLUSION: A single injection of encapsulated HEK293 cells followed by multiple rounds of ifosfamide administration results in repeated anti-tumour activity and halts tumour growth but, in the absence of a functioning immune system, does not cause tumour regression.
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The study of organelle contact sites has received a great impulse due to increased interest in the understanding of their involvement in many disease conditions. Split-GFP-based contact sites (SPLICS) reporters emerged as essential tools to easily detect changes in a wide range of organelle contact sites in cultured cells and in vivo, e.g., in zebrafish larvae. We report here on the generation of a new vector library of SPLICS cloned into a piggyBac system for stable and inducible expression of the reporters in a cell line of interest to overcome any potential weakness due to variable protein expression in transient transfection studies. Stable HeLa cell lines expressing SPLICS between the endoplasmic reticulum (ER) and mitochondria (MT), the ER and plasma membrane (PM), peroxisomes (PO) and ER, and PO and MT, were generated and tested for their ability to express the reporters upon treatment with doxycycline. Moreover, to take advantage of these cellular models, we decided to follow the behavior of different membrane contact sites upon modulating cholesterol traffic. Interestingly, we found that the acute pharmacological inhibition of the intracellular cholesterol transporter 1 (NPC1) differently affects membrane contact sites, highlighting the importance of different interfaces for cholesterol sensing and distribution within the cell.
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Retículo Endoplasmático , Peixe-Zebra , Animais , Colesterol/metabolismo , Retículo Endoplasmático/metabolismo , Células HeLa , Humanos , Análise Espaço-Temporal , Peixe-Zebra/metabolismoRESUMO
Juvenile hormones (JH) regulate insect development and reproduction. The JH analogs (JHA) are used as insecticides. However, JHAs are rarely used in managing pests such as the fall armyworm, Spodoptera frugiperda that cause damage during larval stages. The insecticides that antagonize JH action and induce stoppage of feeding and precocious metamorphosis might work better to control these pests. Treating insects with JHA insecticides induces the expression of an early JH response gene, Krüppel homolog 1 (Kr-h1) by working through JH response elements (JHRE) present in its promoter. In this study, we identified JHREs present in the promoter of Kr-h1 gene of a global pest, S. frugiperda, and used them to develop a JHRE-reporter cell platform to screen for JH analogs. JHA, methoprene induced the expression of SfKr-h1 both in vitro and in vivo. JHRE present in the promoters of two SfKr-h1 isoforms, SfKr-h1α and SfKr-h1ß were identified. In Sf9 cells, the knockout of isoform-specific JHRE affected JH response in an isoform-specific manner. We also found that S. frugiperda JHRE (SfJHRE) did not function in the mosquito Aedes aegypti Aag2 cells and Tribolium castaneum TcA cells. Similarly, Ae. aegypti AaJHRE and T. castaneum TcJHRE were only functional in cells derived from these insects. The nucleotide sequence at the 3'end to the conserved core JHRE E-box sequence seems to be responsible for the species specificity observed. Two stable cell lines expressing the luciferase and enhanced green fluorescent protein genes under the control of SfJHRE were established. These cell lines responded well to JHA; these two JHRE-reporter cell lines could be used in screening assays to identify insecticides to manage S. frugiperda and other major pests.
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Inseticidas , Animais , Spodoptera/genética , Spodoptera/metabolismo , Inseticidas/farmacologia , Especificidade da Espécie , Proteínas de Insetos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Hormônios Juvenis/metabolismo , Metoprene/farmacologia , Metoprene/metabolismo , Insetos/metabolismo , Isoformas de Proteínas/genética , Elementos de Resposta , Fatores de Transcrição Kruppel-Like/metabolismoRESUMO
Mammalian protein expression systems are ideally suited for the high-level production of recombinant eukaryotic secreted and membrane proteins for structural biology applications. Here, we present genetic transduction of HEK293-derived cells using lentivirus as a robust and cost-efficient method for the rapid generation of stable expression cell lines. We describe the features of the lentiviral transfer plasmid pHR-CMV-TetO2, as well as detailed protocols for production of lentiviral particles, determination of functional lentiviral titer, infection of expression cells, culture and expansion of the resulting stable cell lines, their adaptation to adherent and suspension growth, and constitutive or inducible milligram-scale protein production. The typical lead-time for a full production run is ~3-4 weeks, with an anticipated yield of up to tens of milligrams of protein per liter of expression medium.
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Biotecnologia/métodos , Técnicas de Cultura de Células/métodos , Lentivirus/metabolismo , Proteínas Recombinantes/biossíntese , Animais , Linhagem Celular , Vetores Genéticos , Células HEK293 , Humanos , Lentivirus/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Plasmídeos/genética , Proteínas Recombinantes/genética , Transdução Genética/métodos , Transfecção/métodosRESUMO
Multispectral live-cell imaging is an informative approach that permits detecting biological processes simultaneously in the spatial and temporal domain by exploiting spectrally distinct biosensors. However, the combination of fluorescent biosensors with distinct spectral properties such as different sensitivities, and dynamic ranges can undermine accurate co-imaging of the same analyte in different subcellular locales. We advanced a single-color multiparametric imaging method, which allows simultaneous detection of hydrogen peroxide (H2O2) in multiple cell locales (nucleus, cytosol, mitochondria) using the H2O2 biosensor HyPer7. Co-culturing of endothelial cells stably expressing differentially targeted HyPer7 biosensors paved the way for co-imaging compartmentalized H2O2 signals simultaneously in neighboring cells in a single experimental setup. We termed this approach COMPARE IT, which is an acronym for co-culture-based multiparametric imaging technique. Employing this approach, we detected lower H2O2 levels in mitochondria of endothelial cells compared to the cell nucleus and cytosol under basal conditions. Upon administering exogenous H2O2, the cytosolic and nuclear-targeted probes displayed similarly slow and moderate HyPer7 responses, whereas the mitochondria-targeted HyPer7 signal plateaued faster and reached higher amplitudes. Our results indicate striking differences in mitochondrial H2O2 accumulation of endothelial cells. Here, we present the method's potential as a practicable and informative multiparametric live-cell imaging technique.
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Técnicas Biossensoriais , Técnicas de Cocultura , Células Endoteliais/metabolismo , Peróxido de Hidrogênio/metabolismo , MitocôndriasRESUMO
Influenza viruses infect millions of people each year, resulting in significant morbidity and mortality in the human population. Therefore, generation of a universal influenza virus vaccine is an urgent need and would greatly benefit public health. Recombinant protein technology is an established vaccine platform and has resulted in several commercially available vaccines. Herein, we describe the approach for developing stable transfected human cell lines for the expression of recombinant influenza virus hemagglutinin (HA) and recombinant influenza virus neuraminidase (NA) proteins for the purpose of in vitro and in vivo vaccine development. HA and NA are the main surface glycoproteins on influenza virions and the major antibody targets. The benefits for using recombinant proteins for in vitro and in vivo assays include the ease of use, high level of purity and the ability to scale-up production. This work provides guidelines on how to produce and purify recombinant proteins produced in mammalian cell lines through either transient transfection or generation of stable cell lines from plasmid creation through the isolation step via Immobilized Metal Affinity Chromatography (IMAC). Collectively, the establishment of this pipeline has facilitated large-scale production of recombinant HA and NA proteins to high purity and with consistent yields, including glycosylation patterns that are very similar to proteins produced in a human host.
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Lentiviral systems have proven advantageous in the delivery and long-term integration of gene sequences into the genome of several cell types in vitro, in vivo, as well as in clinical trials. Here we detail the protocols involved in the molecular cloning of ADAMTSL2 and ADAMTSL4 into the human immunodeficiency virus (HIV)-derived pCDH lentiviral system. We also describe the lentiviral transduction of ADAMTSL2 and ADAMTSL4 into mammalian HEK293-EBNA cells to create stable cell lines, as well as their recombinant expression.
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Proteínas ADAMTS/genética , Clonagem Molecular/métodos , Transdução Genética/métodos , Proteínas ADAMTS/metabolismo , Vetores Genéticos , Células HEK293 , Humanos , Lentivirus/genética , Proteínas Recombinantes/metabolismoRESUMO
INTRODUCTION: Due to the increasing resistance to nucleot(s)ide analogs in patients with chronic hepatitis B, development of new antiviral drugs to eradicate hepatitis B virus is still urgently needed. MATERIAL AND METHODS: To date, most studies on evaluating anti-HBV drugs have been performed using cell lines where the HBV genomic DNA is chromosomally integrated, e.g. Hep2.2.15 in HBV-infected livers of the viral episomal genome replicates in the nucleus and covalently closed circular DNA (cccDNA) serves as a transcriptional template. Another option involves the use of HBV-infected cells of HepaRG or NTCP-overexpressing cells. However, the development of the infection system is expensive and laborious, and its HBV expression level remained low. RESULTS: Compared to HuH7 cells, the established stable cell lines based on episomal-type pEB-Multi vectors can been expressed HBV wild-type by qRT-PCR and immunoblotting (p < 0.05). These two vectors are also sensitive to Entecavir and against nucleoside analog Lamivudine in mutants cellines. CONCLUSIONS: It is worth demonstrating how useful the established cell system is for evaluating antiviral agents and their mechanisms of action.
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Proximity labeling by ascorbate peroxidase (APEX) requires appropriate experimental setups that generate sufficient signal over background as a prerequisite for downstream analyses by mass spectrometry. Cell culture-based systems are easily accessible, yet, for proximity labeling of small structures must be carefully optimized in order to give satisfying results. How to establish and characterize APEX cell lines will be the topic of this chapter.
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Ascorbato Peroxidases/química , Espectrometria de Massas , Proteômica/métodos , Coloração e Rotulagem/métodos , Animais , HumanosRESUMO
Nuclear Factor kappa B (NF-κB) is a conserved transcription factor involved in the expression of genes that are critical to inflammation and cell survival. Exposure to particular signals results in phosphorylation of NF-κB inhibitor proteins, which in turn allows NF-κB dimers to translocate to the nucleus and induce gene expression. Pathologic consequences of NF-κB activation are vast, mainly because of the pleiotropic roles that NF-κB-induced genes have on inflammation, cell proliferation and apoptosis. Thus, experimental models assessing NF-κB activation have direct screening applications for drug discovery. In this scenario, pathway-specific reporter cell systems become valuable tools to identify and elucidate the mechanism of action of novel compounds. Here, we describe the generation, characterization, and validation of human cancer epithelial reporter cell lines for functional studies of NF-κB activation by different pro- and anti-inflammatory mediators. Human lung (H460) and breast (T-47D) cancer cell lines were transfected with a pNF-κB-hrGFP plasmid which contains the GFP gene under the control of NF-κB binding elements. The pro-inflammatory cytokine TNF-α was able to activate the reporter systems in a concentration-response manner, correlating to the activation of the NF-κB signaling pathway. Finally, the reporter cell lines were validated using dexamethasone, a potent anti-inflammatory drug, a synthetic inhibitor of NF-κB (BAY 11-7082) and a new anti-cancer peptide (CIGB-552). We have established robust H460-NF-κB-hrGFP and T-47D-NF-κB-hrGFP reporter cell lines which represent a useful cancer model for primary screening and identification of compounds with anti-inflammatory activity.
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Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral/metabolismo , Descoberta de Drogas/métodos , Neoplasias Pulmonares/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Feminino , Humanos , Modelos Biológicos , Reprodutibilidade dos TestesRESUMO
Recombinant proteins, such as monoclonal antibodies, are produced in mammalian cell lines to introduce proper protein folding and post-translational modifications, which are essential for full biological activity. In both the industrial and academic environments, the use of recombinant proteins varies widely and, with it, the method of production. The amount of an antibody needed for a toxicity study is far greater than that needed by a research lab performing cellular assays, and the amount of effort put into the development of the protein will vary accordingly. There is no universal strategy for mammalian expression systems, and scientists often struggle to develop a suitable process from the myriad of choices at each step. Here, we elaborate on the various obstacles encountered when planning high-yield experiments to produce the recombinant proteins of interest. © 2018 by John Wiley & Sons, Inc.
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Expressão Gênica , Proteínas Recombinantes/biossíntese , Animais , Humanos , Proteínas Recombinantes/genéticaRESUMO
INTRODUCTION: Cytokines activated in response to immunosuppressive viral infections can directly or indirectly affect the neoplastic transformation of B cells. In this study, we studied a new substance designed to produce the antiviral drug CelAgrip (CA, CelAgripus), which exhibits interferon (IFN) and cytokine-inducing activity and, apparently, can be used as an activator of antiviral immunity. Purpose - is to evaluate the cytokine-regulating effect of CA in Burkitt's lymphoma (LB) cell lines latently infected with the Epstein-Barr virus (EBV). OBJECTIVES: to study the CA-induced expression of the cytokine genes IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17, IL-18, IFN-α, IFN -γ, IFN-ß, IFN-λ1, IFN-λ2, IFN-λ3, TNF-α in normal and EBV transformed LB cells. MATERIAL AND METHODS: Cell line: the human embryo fibroblasts (HEF), Namalva, Daudi, Raji, P3HR-1. Preparations: CA, gossypol-acetic acid (GAA), sodium carboxymethyl cellulose (Na-CMC). METHODS: RT-PCR and methods for assessing cytotoxicity (MTT and Scepter 2.0 Merck cell counter). RESULTS: The effect of the CA preparation on the expression of IFN-λ, IL-1ß, IL-6, IL-8 and IL-10 genes was revealed. DISCUSSION: We observed the activation of gene expression of IFN-λ, IL-1ß, IL-6, IL-8 and suppression of IL-10 gene activity when treatment CA of LB cells. CONCLUSION: The substance CA has new effects on the activation of the expression of a number of key cytokine genes in stable Burkitt lymphoma cell lines.