RESUMEN
The classic dual luciferase reporter assay has been widely used to rapidly and accurately determine the transcriptional activity of a given promoter induced by certain signal pathways in the cells. In particular, the sensitive characteristics of luciferase highlight its significance in many experiments, such as weak promoter analysis, transfection studies using small amounts of DNA, and detection in cell lines with low transfection efficiency. This chapter presents detailed information and experimental procedures for measuring interferon (IFN)-induced Interferon-Stimulated Response Element (ISRE) promoter activity using the dual luciferase reporter assay.
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Genes Reporteros , Interferones , Luciferasas , Regiones Promotoras Genéticas , Elementos de Respuesta , Transducción de Señal , Humanos , Interferones/metabolismo , Interferones/genética , Luciferasas/metabolismo , Luciferasas/genética , Transfección , AnimalesRESUMEN
Optimizations of the gene expression cassette combined with the selection of an appropriate signal peptide are important factors that must be considered to enhance heterologous protein expression in Chinese Hamster Ovary (CHO) cells. In this study, we investigated the effectiveness of different signal peptides on the production of recombinant human chorionic gonadotropin (r-hCG) in CHO-K1 cells. Four optimized expression constructs containing four promising signal peptides were stably transfected into CHO-K1 cells. The generated CHO-K1 stable pool was then evaluated for r-hCG protein production. Interestingly, human serum albumin and human interleukin-2 signal peptides exhibited relatively greater extracellular secretion of the r-hCG with an average yield of (16.59 ± 0.02 µg/ml) and (14.80 ± 0.13 µg/ml) respectively compared to the native and murine IgGκ light chain signal peptides. The stably transfected CHO pool was further used as the cell substrate to develop an optimized upstream process followed by a downstream phase of the r-hCG. Finally, the biological activity of the purified r-hCG was assessed using in vitro bioassays. The combined data highlight that the choice of signal peptide can be imperative to ensure an optimal secretion of a recombinant protein in CHO cells. In addition, the stable pool technology was a viable approach for the production of biologically active r-hCG at a research scale with acceptable bioprocess performances and consistent product quality.
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Gonadotropina Coriónica , Cricetulus , Proteínas Recombinantes , Células CHO , Animales , Proteínas Recombinantes/genética , Proteínas Recombinantes/biosíntesis , Humanos , Gonadotropina Coriónica/genética , Gonadotropina Coriónica/biosíntesis , Gonadotropina Coriónica/farmacología , Cricetinae , Señales de Clasificación de Proteína/genética , Expresión Génica , TransfecciónRESUMEN
Gene therapy offers a promising avenue for treating ischemic diseases, yet its clinical efficacy is hindered by the limitations of single gene therapy and the high oxidative stress microenvironment characteristic of such conditions. Lipid-polymer hybrid vectors represent a novel approach to enhance the effectiveness of gene therapy by harnessing the combined advantages of lipids and polymers. In this study, we engineered lipid-polymer hybrid nanocarriers with tailored structural modifications to create a versatile membrane fusion lipid-nuclear targeted polymer nanodelivery system (FLNPs) optimized for gene delivery. Our results demonstrate that FLNPs facilitate efficient cellular uptake and gene transfection via membrane fusion, lysosome avoidance, and nuclear targeting mechanisms. Upon encapsulating Hepatocyte Growth Factor plasmid (pHGF) and Catalase plasmid (pCAT), HGF/CAT-FLNPs were prepared, which significantly enhanced the resistance of C2C12 cells to H2O2-induced injury in vitro. In vivo studies further revealed that HGF/CAT-FLNPs effectively alleviated hindlimb ischemia-induced gangrene, restored motor function, and promoted blood perfusion recovery in mice. Metabolomics analysis indicated that FLNPs didn't induce metabolic disturbances during gene transfection. In conclusion, FLNPs represent a versatile platform for multi-dimensional assisted gene delivery, significantly improving the efficiency of gene delivery and holding promise for effective synergistic treatment of lower limb ischemia using pHGF and pCAT.
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Terapia Genética , Isquemia , Lípidos , Polímeros , Animales , Isquemia/terapia , Terapia Genética/métodos , Lípidos/química , Ratones , Polímeros/química , Nanopartículas/química , Factor de Crecimiento de Hepatocito/genética , Línea Celular , Transfección/métodos , Plásmidos/genética , Técnicas de Transferencia de Gen , Masculino , Miembro Posterior/irrigación sanguínea , Catalasa/metabolismoRESUMEN
Delivering foreign molecules and genetic material into cells is a crucial process in life sciences and biotechnology, resulting in great interest in effective cell transfection methods. Importantly, physical transfection methods allow delivery of molecules of different chemical composition and are, thus, very flexible. Here, we investigated the influence of microwave radiation on the transfection and survival of mammalian cells. We made use of an optimized microwave-poration device and analyzed its performance (frequency and electric field strength) in comparison with simulations. We, then, tested the effect of microwave irradiation on cells and found that 18 GHz had the least impact on cell survival, viability, cell division and genotoxicity while 10 GHz drastically impacted cell physiology. Using live-cell fluorescence microscopy and image analysis, we tested the uptake of small chemical substances, which was most efficient at 18 GHz and correlated with electric field strength and frequency. Finally, we were able to obtain cellular uptake of molecules of very different chemical composition and sizes up to whole immunoglobulin antibodies. In conclusion, microwave-induced poration enables the uptake of widely different substances directly into mammalian cells growing as adherent cultures and with low physiological impact.
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Membrana Celular , Supervivencia Celular , Microondas , Membrana Celular/metabolismo , Animales , Humanos , Transfección , Células CHO , CricetulusRESUMEN
Purpose: Progressive choroid and retinal pigment epithelial (RPE) degeneration causing vision loss is a unique characteristic of long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD), a fatty acid oxidation disorder caused by a common c.1528G>C pathogenic variant in HADHA, the α subunit of the mitochondrial trifunctional protein (TFP). We established and characterized an induced pluripotent stem cell (iPSC)-derived RPE cell model from cultured skin fibroblasts of patients with LCHADD and tested whether addition of wildtype (WT) HAHDA could rescue the phenotypes identified in LCHADD-RPE. Methods: We constructed an rAAV expression vector containing 3' 3xFLAG-tagged human HADHA cDNA under the transcriptional control of the cytomegalovirus (CMV) enhancer-chicken beta actin (CAG) promoter (CAG-HADHA-3XFLAG). LCHADD-RPE were cultured, matured, and transduced with either AAV-GFP (control) or AAV-HADHA-3XFLAG. Results: LCHADD-RPE express TFP subunits and accumulate 3-hydroxy-acylcarnitines, cannot oxidize palmitate, and release fewer ketones than WT-RPE. When LCHADD-RPE are exposed to docosahexaenoic acid (DHA), they have increased oxidative stress, lipid peroxidation, decreased viability, and are rescued by antioxidant agents potentially explaining the pathologic mechanism of RPE loss in LCHADD. Transduced LCHADD-RPE expressing a WT copy of TFPα incorporated TFPα-FLAG into the TFP complex in the mitochondria and accumulated significantly less 3-hydroxy-acylcarnitines, released more ketones in response to palmitate, and were more resistant to oxidative stress following DHA exposure than control. Conclusions: iPSC-derived LCHADD-RPE are susceptible to lipid peroxidation mediated cell death and are rescued by exogenous HADHA delivered with rAAV. These results are promising for AAV-HADHA gene addition therapy as a possible treatment for chorioretinopathy in patients with LCHADD.
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Dependovirus , Vectores Genéticos , Células Madre Pluripotentes Inducidas , Peroxidación de Lípido , 3-Hidroxiacil-CoA Deshidrogenasa de Cadena Larga , Epitelio Pigmentado de la Retina , Transfección , Humanos , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/citología , Células Madre Pluripotentes Inducidas/metabolismo , Dependovirus/genética , Células Cultivadas , 3-Hidroxiacil-CoA Deshidrogenasa de Cadena Larga/genética , 3-Hidroxiacil-CoA Deshidrogenasa de Cadena Larga/metabolismo , Errores Innatos del Metabolismo Lipídico/genética , Errores Innatos del Metabolismo Lipídico/metabolismo , Errores Innatos del Metabolismo Lipídico/terapia , Proteína Trifuncional Mitocondrial/genética , Proteína Trifuncional Mitocondrial/deficiencia , Miopatías Mitocondriales/genética , Miopatías Mitocondriales/metabolismo , Terapia Genética/métodos , Cardiomiopatías , Enfermedades del Sistema Nervioso , RabdomiólisisRESUMEN
Lipid nanoparticles (LNPs) are currently the most commonly used non-viral gene delivery system. Their physiochemical attributes, encompassing size, charge and surface modifications, significantly affect their behaviors both in vivo and in vitro. Nevertheless, the effects of these properties on the transfection and distribution of LNPs after intramuscular injection remain elusive. In this study, LNPs with varying sizes, lipid-based charges and PEGylated lipids were formulated to study their transfection and in vivo distribution. Luciferase mRNA (mLuc) was entraped in LNPs as a model nucleic acid molecule. Results indicated that smaller-sized LNPs and those with neutral potential presented superior transfection efficiency after intramuscular injection. Surprisingly, the sizes and charges did not exert a notable influence on the in vivo distribution of the LNPs. Furthermore, PEGylated lipids with shorter acyl chains contributed to enhanced transfection efficiency due to their superior cellular uptake and lysosomal escape capabilities. Notably, the mechanisms underlying cellular uptake differed among LNPs containing various types of PEGylated lipids, which was primarily attributed to the length of their acyl chain. Together, these insights underscore the pivotal role of nanoparticle characteristics and PEGylated lipids in the intramuscular route. This study not only fills crucial knowledge gaps but also provides significant directions for the effective delivery of mRNA via LNPs.
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Lípidos , Nanopartículas , Tamaño de la Partícula , Polietilenglicoles , ARN Mensajero , Transfección , Nanopartículas/química , Animales , Polietilenglicoles/química , Inyecciones Intramusculares , Lípidos/química , Transfección/métodos , Ratones , Técnicas de Transferencia de Gen , Humanos , Luciferasas/metabolismo , Luciferasas/genética , Propiedades de Superficie , LiposomasRESUMEN
Gene therapy has emerged as a potent tool for treating a wide range of hereditary and acquired disorders. However, the development of high-performance nonviral gene delivery vectors remains a significant challenge. Here we report the development of a new type of star-shaped poly(ß-amino ester) (SPAE) through a "top-down" hydrolysis approach and demonstrate its exceptional DNA transfection efficiency and safety profiles. Two SPAEs with different monomer combinations are first synthesized using an "arm first" strategy and then hydrolyzed sequentially to produce h-SPAEs with varied chemical compositions and molecular weights. Results demonstrate that hydrolysis significantly influences the physiological characteristics of the resulting h-SPAEs and h-SPAE/DNA polyplexes. Dependent on the chemical composition, h-SPAEs with low to moderate hydrolysis degrees exhibit superior gene transfection efficiency and cell viability across various cell types. Notably, the leading candidate, h-SPAE-1-5h, achieves up to 88.8% gene transfection efficiency, which was 154-257% higher compared to SPAE-1. This study not only establishes an easy-to-operate "top-down" approach for reshaping the topological structure and chemical composition of SPAEs, but also identifies promising candidates for effective gene transfection. This strategy can be applied to other cationic polymers to enhance their gene transfection performance.
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Supervivencia Celular , ADN , Polímeros , Transfección , Hidrólisis , Transfección/métodos , Humanos , Polímeros/química , ADN/química , ADN/genética , Supervivencia Celular/efectos de los fármacos , Células HEK293RESUMEN
This study investigates the synthesis and optimization of nanobots (NBs) loaded with pDNA using the layer-by-layer (LBL) method and explores the impact of their collective motion on the transfection efficiency. NBs consist of biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) nanoparticles and are powered by the urease enzyme, enabling autonomous movement and collective swarming behavior. In vitro experiments were conducted to validate the delivery efficiency of fluorescently labeled NBs, using two-dimensional (2D) and three-dimensional (3D) cell models: murine urothelial carcinoma cell line (MB49) and spheroids from human urothelial bladder cancer cells (RT4). Swarms of pDNA-loaded NBs showed enhancements of 2.2- to 2.6-fold in delivery efficiency and 6.8- to 8.1-fold in material delivered compared to inhibited particles (inhibited enzyme) and the absence of fuel in a 2D cell culture. Additionally, efficient intracellular delivery of pDNA was demonstrated in both cell models by quantifying and visualizing the expression of eGFP. Swarms of NBs exhibited a >5-fold enhancement in transfection efficiency compared to the absence of fuel in a 2D culture, even surpassing the Lipofectamine 3000 commercial transfection agent (cationic lipid-mediated transfection). Swarms also demonstrated up to a 3.2-fold enhancement in the amount of material delivered in 3D spheroids compared to the absence of fuel. The successful transfection of 2D and 3D cell cultures using swarms of LBL PLGA NBs holds great potential for nucleic acid delivery in the context of bladder treatments.
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ADN , Nanopartículas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Humanos , Animales , Ratones , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Línea Celular Tumoral , Nanopartículas/química , ADN/química , ADN/metabolismo , Transfección/métodos , Ureasa/metabolismo , Ureasa/química , Ureasa/genética , Plásmidos/metabolismo , Plásmidos/genética , Plásmidos/química , Técnicas de Transferencia de Gen , Ácido Poliglicólico/química , Ácido Láctico/química , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/terapiaRESUMEN
High molecular weight polyethylenimine (HMW PEI; branched 25 kDa PEI) has been widely investigated for gene delivery due to its high transfection efficiency. However, the toxicity and lack of targeting to specific cells have limited its clinical application. In the present investigation, L-3, 4-dihydroxyphenylalanine (L-DOPA) was conjugated on HMW PEI in order to target L-type amino acid transporter 1 (LAT-1) and modulate positive charge density on the surface of polymer/plasmid complexes (polyplexes). The results of biophysical characterization revealed that the PEI conjugates are able to form nanoparticles ≤ 180 nm with the zeta potential ranging from + 9.5-12.4 mV. These polyplexes could condense plasmid DNA and protect it against nuclease digestion at the carrier to plasmid ratios higher than 4. L-DOPA conjugated PEI derivatives were complexed with a plasmid encoding human interleukin-12 (hIL-12). Targeted polyplexes showed up to 2.5 fold higher transfection efficiency in 4T1 murine mammary cancer cell line, which expresses LAT-1, than 25 kDa PEI polyplexes prepared in the same manner. The cytotoxicity of these polyplexes was also substantially lower than the unmodified parent HMW PEI. These results support the use of L-3, 4-dihydroxyphenylalanine derivatives of PEI in any attempt to develop a LAT-1 targeted gene carrier.
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Peso Molecular , Plásmidos , Polietileneimina , Polietileneimina/química , Plásmidos/genética , Plásmidos/química , Animales , Ratones , Línea Celular Tumoral , Humanos , Dihidroxifenilalanina/química , Transfección/métodos , Técnicas de Transferencia de Gen , Interleucina-12/metabolismo , Interleucina-12/genética , Transportador de Aminoácidos Neutros Grandes 1/metabolismo , Transportador de Aminoácidos Neutros Grandes 1/genética , Nanopartículas/química , ADN/químicaRESUMEN
Genome editing is recognized as a powerful tool in agriculture and research, enhancing our understanding of genetic function, diseases, and productivity. However, its progress in buffaloes has lagged behind other mammals due to several challenges, including long gestational periods, single pregnancies, and high raising costs. In this study, we aimed to generate MSTN-edited buffaloes, known for their distinctive double-muscling phenotype, as a proof of concept. To meet our goal, we used somatic cell nuclear transfer (SCNT) and zygotic electroporation (CRISPR-EP) technique. For this, we firstly identified the best transfection method for introduction of RNP complex into fibroblast which was further used for SCNT. For this, we compared the transfection, cleavage efficiency and cell viability of nucleofection and lipofection in adult fibroblasts. The cleavage, transfection efficiency and cell viability of nucleofection group was found to be significantly (P ≤ 0.05) higher than lipofection group. Four MSTN edited colony were generated using nucleofection, out of which three colonies was found to be biallelic and one was monoallelic. Further, we compared the efficacy, embryonic developmental potential and subsequent pregnancy outcome of SCNT and zygotic electroporation. The blastocyst rate of electroporated group was found to be significantly (P ≤ 0.05) higher than SCNT group. However, the zygotic electroporation group resulted into two pregnancies which were confirmed to be MSTN edited. Since, the zygotic electroporation does not require complex micromanipulation techniques associated with SCNT, it has potential for facilitating the genetic modification in large livestock such as buffaloes. The present study lays the basis for inducing genetic alternation with practical or biological significance.
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Búfalos , Sistemas CRISPR-Cas , Electroporación , Edición Génica , Técnicas de Transferencia Nuclear , Transfección , Animales , Búfalos/genética , Electroporación/veterinaria , Electroporación/métodos , Femenino , Embarazo , Edición Génica/métodos , Edición Génica/veterinaria , Transfección/veterinaria , Transfección/métodos , Técnicas de Transferencia Nuclear/veterinaria , Miostatina/genética , Cigoto/metabolismoRESUMEN
Metal-organic frameworks (MOFs) have the potential to efficiently carry cargo due to their excellent porosity and high surface area. Nevertheless, conventional MOFs and their derivatives exhibit low efficiency in transporting nucleic acids and other small molecules, as well as having poor colloidal stability. In this study, a ZIF-90 loaded with iron oxide nanoparticles and Au nanorods was prepared, and then surface-functionalized with polyethyleneimine (PEI) to create a multifunctional nanocomposite (AFZP25k) with pH, photothermal, and magnetic responsiveness. AFZP25k can condense plasmid DNA to form AFZP25k/DNA complexes, with a maximum binding efficiency of 92.85 %. DNA release assay showed significant light and pH responsiveness, with over 80 % cumulative release after 6 h of incubation. When an external magnetic field is applied, the cellular uptake efficiency in HeLa cells reached 81.51 %, with low cytotoxicity and specific distribution. In vitro transfection experiments demonstrated a gene transfection efficiency of 44.77 % in HeLa cells. Following near-infrared irradiation, the uptake efficiency and transfection efficiency of AFZP25k in HeLa cells increased by 21.3 % and 13.59 % respectively. The findings indicate the potential of AFZP25k as an efficient and targeted gene delivery vector in cancer gene therapy.
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Técnicas de Transferencia de Gen , Oro , Estructuras Metalorgánicas , Humanos , Estructuras Metalorgánicas/química , Células HeLa , Oro/química , Transfección/métodos , Neoplasias/terapia , Neoplasias/genética , Vectores Genéticos/química , Vectores Genéticos/genética , Polietileneimina/química , ADN/química , ADN/genética , Plásmidos/genética , Nanotubos/química , Concentración de Iones de HidrógenoRESUMEN
Gene transfection, defined by the delivery of nucleic acids into cellular compartments, stands as a crucial procedure in gene therapy. While branched polyethylenimine (PEI) is widely regarded as the "gold standard" for nonviral vectors, its cationic nature presents several issues, including nonspecific protein adsorption and notable cytotoxicity. Additionally, it often fails to achieve high transfection efficiency, particularly with hard-to-transfect cell types. To overcome these challenges associated with PEI as a vector for plasmid DNA (pDNA), the photothermal agent indocyanine green (ICG) is integrated with PEI and pDNA to form the PEI/ICG/pDNA (PI/pDNA) complex for more efficient and safer gene transfection. The negatively charged ICG serves a dual purpose: neutralizing PEI's excessive positive charges to reduce cytotoxicity and, under near-infrared irradiation, inducing local heating that enhances cell membrane permeability, thus facilitating the uptake of PI/pDNA complexes to boost transfection efficiency. Using pDNA encoding vascular endothelial growth factor as a model, our system shows enhanced transfection efficiency in vitro for hard-to-transfect endothelial cells, leading to improved cell proliferation and migration. Furthermore, in vivo studies reveal the therapeutic potential of this system in accelerating the healing of infected wounds by promoting angiogenesis and reducing inflammation. This approach offers a straightforward and effective method for gene transfection, showing potentials for tissue engineering and cell-based therapies.
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Verde de Indocianina , Plásmidos , Polietileneimina , Transfección , Verde de Indocianina/química , Verde de Indocianina/farmacología , Polietileneimina/química , Humanos , Transfección/métodos , Animales , Plásmidos/genética , Plásmidos/metabolismo , Plásmidos/química , Ratones , ADN/química , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Células Endoteliales de la Vena Umbilical Humana , Proliferación Celular/efectos de los fármacosRESUMEN
Skeletal muscle, which is predominantly constituted by multinucleated muscle fibers, plays a pivotal role in sustaining bodily movements and energy metabolism. Myoblasts, which serve as precursor cells for differentiation and fusion into muscle fibers, are of critical importance in the exploration of the functional genes associated with embryonic muscle development. However, the in vitro proliferation of primary myoblasts is inherently constrained. In this study, we achieved a significant breakthrough by successfully establishing a chicken myoblast cell line through the introduction of the exogenous chicken telomerase reverse transcriptase (chTERT) gene, followed by rigorous G418-mediated pressure screening. This newly developed cell line, which was designated as chTERT-myoblasts, closely resembled primary myoblasts in terms of morphology and exhibited remarkable stability in culture for at least 20 generations of population doublings without undergoing malignant transformation. In addition, we conducted an exhaustive analysis that encompassed cellular proliferation, differentiation, and transfection characteristics. Our findings revealed that the chTERT-myoblasts had the ability to proliferate, differentiate, and transfect after multiple rounds of population doublings. This achievement not only furnished a valuable source of homogeneous avian cell material for investigating embryonic muscle development, but also provided valuable insights and methodologies for establishing primary cell lines.
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Diferenciación Celular , Proliferación Celular , Pollos , Mioblastos , Telomerasa , Animales , Mioblastos/citología , Mioblastos/metabolismo , Línea Celular , Telomerasa/metabolismo , Telomerasa/genética , Desarrollo de Músculos/genética , Técnicas de Cultivo de Célula/métodos , Transfección , Embrión de PolloRESUMEN
Targeting, safety, scalability, and storage stability of vectors are still challenges in the field of nucleic acid delivery for gene therapy. Silica-based nanoparticles have been widely studied as gene carriers, exhibiting key features such as biocompatibility, simplistic synthesis, and enabling easy surface modifications for targeting. However, the ability of the formulation to incorporate DNA is limited, which restricts the number of DNA molecules that can be incorporated into the particle, thereby reducing gene expression. Here we use polymerase chain reaction (PCR)-generated linear DNA molecules to augment the coding sequences of gene-carrying nanoparticles, thereby maximizing nucleic acid loading and minimizing the size of these nanocarriers. This approach results in a remarkable 16-fold increase in protein expression six days post-transfection in cells transfected with particles carrying the linear DNA compared with particles bearing circular plasmid DNA. The study also showed that the use of linear DNA entrapped in DNA@SiO2 resulted in a much more efficient level of gene expression compared to standard transfection reagents. The system developed in this study features simplicity, scalability, and increased transfection efficiency and gene expression over existing approaches, enabled by improved embedment capabilities for linear DNA, compared to conventional methods such as lipids or polymers, which generally show greater transfection efficiency with plasmid DNA. Therefore, this novel methodology can find applications not only in gene therapy but also in research settings for high-throughput gene expression screenings.
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ADN , Técnicas de Transferencia de Gen , Nanopartículas , Plásmidos , Dióxido de Silicio , Transfección , Dióxido de Silicio/química , Nanopartículas/química , ADN/administración & dosificación , ADN/genética , ADN/química , Transfección/métodos , Humanos , Plásmidos/administración & dosificación , Terapia Genética/métodos , Tamaño de la PartículaRESUMEN
Replicons, derived from RNA viruses, are genetic constructs retaining essential viral enzyme genes while lacking key structural protein genes. Upon introduction into cells, the genes carried by the replicon RNA are expressed, and the RNA self-replicates, yet viral particle production does not take place. Typically, RNA replicons are transcribed in vitro and are then electroporated in cells. However, it would be advantageous for the replicon to be generated in cells following DNA transfection instead of RNA. In this study, a bacterial artificial chromosome (BAC) DNA encoding a SARS-CoV-2 replicon under control of a T7 promoter was transfected into HEK293T cells engineered to functionally express the T7 RNA polymerase (T7 RNAP). Upon transfection of the BAC DNA, we observed low, but reproducible expression of reporter proteins GFP and luciferase carried by this replicon. Expression of the reporter proteins required linearization of the BAC DNA prior to transfection. Moreover, expression occurred independently of T7 RNAP. Gene expression was also insensitive to remdesivir treatment, suggesting that it did not involve self-replication of replicon RNA. Similar results were obtained in highly SARS-CoV-2 infection-permissive Calu-3 cells. Strikingly, prior expression of the SARS-CoV-2 N protein boosted expression from transfected SARS-CoV-2 RNA replicon but not from the replicon BAC DNA. In conclusion, transfection of a large DNA encoding a coronaviral replicon led to reproducible replicon gene expression through an unidentified mechanism. These findings highlight a novel pathway toward replicon gene expression from transfected replicon cDNA, offering valuable insights for the development of methods for DNA-based RNA replicon applications.
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Genes Reporteros , Replicación de ARN , ARN Viral , Replicón , SARS-CoV-2 , Humanos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Cromosomas Artificiales Bacterianos/genética , COVID-19/virología , COVID-19/genética , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Regiones Promotoras Genéticas , Replicón/genética , Replicación de ARN/genética , ARN Viral/genética , ARN Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Transfección , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
The lipopolyplex, a multicomponent nonviral gene carrier, generally demonstrates superior colloidal stability, reduced cytotoxicity, and high transfection efficiency. In this study, a new concept, photochemical reaction-induced transfection, using photosensitizer (PS)-loaded lipopolyplexes was applied, which led to enhanced transfection and cytotoxic effects by photoexcitation of the photosensitizer. Hypericin, a hydrophobic photosensitizer, was encapsulated in the lipid bilayer of liposomes. The preformed nanosized hypericin liposomes enclosed the linear polyethylenimine (lPEI)/pDNA polyplexes, resulting in the formation of hypericin lipopolyplexes (Hy-LPP). The diameters of Hy-LPP containing 50 nM hypericin and 0.25 µg of pDNA were 185.6 ± 7.74 nm and 230.2 ± 4.60 nm, respectively, measured by dynamic light scattering (DLS) and atomic force microscopy (AFM). Gel electrophoresis confirmed the encapsulation of hypericin and pDNA in lipopolyplexes. Furthermore, in vitro irradiation of intracellular Hy-LPP at radiant exposures of 200, 600, and 1000 mJ/cm2 was evaluated. It demonstrated 60- to 75-fold higher in vitro luciferase expression than that in nonirradiated cells. The lactate dehydrogenase (LDH) assay supported that reduced transfection was a consequence of photocytotoxicity. The developed photosensitizer-loaded lipopolyplexes improved the transfection efficiency of an exogenous gene or induced photocytotoxicity; however, the frontier lies in the applied photochemical dose. The light-triggered photoexcitation of intracellular hypericin resulted in the generation of reactive oxygen species (ROS), leading to photoselective transfection in HepG2 cells. It was concluded that the two codelivered therapeutics resulted in enhanced transfection and a photodynamic effect by tuning the applied photochemical dose.
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Antracenos , Carcinoma Hepatocelular , Liposomas , Neoplasias Hepáticas , Perileno , Fármacos Fotosensibilizantes , Transfección , Perileno/química , Perileno/análogos & derivados , Perileno/farmacología , Antracenos/química , Humanos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Transfección/métodos , Liposomas/química , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/patología , Células Hep G2 , ADN/química , Polietileneimina/química , Polietileneimina/farmacología , Plásmidos/química , Supervivencia Celular/efectos de los fármacosRESUMEN
BACKGROUND: Lymphatic valves are specialized structures in collecting lymphatic vessels and are crucial for preventing retrograde lymph flow. Mutations in valve-forming genes have been clinically implicated in the pathology of congenital lymphedema. Lymphatic valves form when oscillatory shear stress from lymph flow signals through the PI3K/AKT pathway to promote the transcription of valve-forming genes that trigger the growth and maintenance of lymphatic valves. Conventionally, in many cell types, AKT is phosphorylated at Ser473 by the mTORC2 (mammalian target of rapamycin complex 2). However, mTORC2 has not yet been implicated in lymphatic valve formation. METHODS: In vivo and in vitro techniques were used to investigate the role of Rictor, a critical component of mTORC2, in lymphatic endothelium. RESULTS: Here, we showed that embryonic and postnatal lymphatic deletion of Rictor, a critical component of mTORC2, led to a significant decrease in lymphatic valves and prevented the maturation of collecting lymphatic vessels. RICTOR knockdown in human dermal lymphatic endothelial cells not only reduced the level of activated AKT and the expression of valve-forming genes under no-flow conditions but also abolished the upregulation of AKT activity and valve-forming genes in response to oscillatory shear stress. We further showed that the AKT target, FOXO1 (forkhead box protein O1), a repressor of lymphatic valve formation, had increased nuclear activity in Rictor knockout mesenteric lymphatic endothelial cells in vivo. Deletion of Foxo1 in Rictor knockout mice restored the number of valves to control levels in lymphatic vessels of the ear and mesentery. CONCLUSIONS: Our work identifies a novel role for RICTOR in the mechanotransduction signaling pathway, wherein it activates AKT and prevents the nuclear accumulation of the valve repressor, FOXO1, which ultimately enables the formation and maintenance of lymphatic valves.
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Proteínas Portadoras , Proteína Forkhead Box O1 , Linfangiogénesis , Vasos Linfáticos , Diana Mecanicista del Complejo 2 de la Rapamicina , Mecanotransducción Celular , Ratones Noqueados , Proteínas Proto-Oncogénicas c-akt , Proteína Asociada al mTOR Insensible a la Rapamicina , Transducción de Señal , Animales , Proteína Asociada al mTOR Insensible a la Rapamicina/metabolismo , Proteína Asociada al mTOR Insensible a la Rapamicina/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Vasos Linfáticos/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/genética , Humanos , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Células Endoteliales/metabolismo , Células Cultivadas , Serina-Treonina Quinasas TOR/metabolismo , Fosforilación , Factores de Transcripción Forkhead/metabolismo , Factores de Transcripción Forkhead/genética , Ratones , Complejos Multiproteicos/metabolismo , Complejos Multiproteicos/genética , Ratones Endogámicos C57BL , Interferencia de ARN , TransfecciónRESUMEN
HYPOTHESIS: Microneedle-mediated intracochlear injection of siRNA-Lipofectamine through the round window membrane (RWM) can be used to transfect cells within the cochlea. BACKGROUND: Our laboratory has developed 100-µm diameter hollow microneedles for intracochlear injection through the guinea pig RWM. In this study, we test the feasibility of microneedle-mediated injection of siRNA and Lipofectamine, a commonly used reagent with known cellular toxicity, through the RWM for cochlear transfection. METHODS: Fluorescently labeled scramble siRNA was diluted into Lipofectamine RNAiMax and OptiMEM. One microliter of 5 µM siRNA was injected through the RWM of Hartley guinea pigs at a rate of 1 µl/min (n = 22). In a control group, 1.0 µl of Lipofectamine, with no siRNA, was diluted into OptiMEM and injected in a similar fashion (n = 5). Hearing tests were performed before and either at 24 hours, 48 hours, or 5 days after injection. Afterward, animals were euthanized, and cochleae were harvested for imaging. Control cochleae were processed in parallel to untreated guinea pigs. RESULTS: Fluorescence, indicating successful transfection, was observed within the basal and middle turns of the cochlea with limited distribution in the apex at 24 and 48 hours. Signal was most intense in the organ of Corti, spiral ligament, and spiral ganglion. Little to no fluorescence was observed at 5 days post-injection. No significant changes in auditory brainstem response (ABR) were noted post-perforation at 5 days, suggesting that siRNA-Lipofectamine at low doses does not cause cochlear toxicity. CONCLUSIONS: Small volumes of siRNA and Lipofectamine can be effectively delivered to cochlear structures using microneedles, paving the way for atraumatic cochlear gene therapy.
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Terapia Genética , Liposomas , ARN Interferente Pequeño , Transfección , Animales , Cobayas , ARN Interferente Pequeño/administración & dosificación , Transfección/métodos , Terapia Genética/métodos , Lípidos/administración & dosificación , Lípidos/química , Cóclea , Ventana Redonda , Agujas , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Oído Interno , Microinyecciones/métodosRESUMEN
The cell intrinsic mechanisms directing peripheral nerve regeneration have remained largely understudied, thus limiting our understanding of these processes and constraining the advancement of novel clinical therapeutics. The use of primary adult rat dorsal root ganglion (DRG) neurons cultured in vitro is well established. Despite this, these cells can be challenging to culture and have so far not been amenable to robust transfection or live-cell imaging. The ability to transfect these cells with fluorescent plasmid constructs to label subcellular structures, combined with high resolution time-lapse imaging has the potential to provide invaluable insight into how peripheral neurons coordinate their regenerative response, and which specific cellular structures are involved in this process. Here we describe a protocol that facilitates transfection and subsequent live-imaging of adult rat DRG neurons.
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Ganglios Espinales , Regeneración Nerviosa , Neuronas , Animales , Ganglios Espinales/citología , Regeneración Nerviosa/fisiología , Ratas , Neuronas/citología , Neuronas/fisiología , Neuronas/metabolismo , Células Cultivadas , Transfección/métodos , Imagen de Lapso de Tiempo/métodosRESUMEN
Epitope tagging represents a powerful strategy for expedited identification, isolation, and characterization of proteins in molecular biological studies, including protein-protein interactions. We aimed to improve the reproducibility of epitope-tagged protein expression and detection by developing a range of plasmids as positive controls. The pJoseph2 family of expression plasmids functions in diverse cellular environments and cell types to enable the evaluation of transfection efficiency and antibody staining for epitope detection. The expressed green fluorescent proteins harbor five unique epitope tags, and their efficient expression in Escherichia coli, Drosophila Schneider's line 2 cells, and human SKOV3 and HEK293T cells was demonstrated by fluorescence microscopy and western blotting. The pJoseph2 plasmids provide versatile and valuable positive controls for numerous experimental applications.
Epitope tagging, a fundamental technique in molecular biology, involves attaching short amino acid sequences (epitope tags) to target proteins for their efficient identification and study. This technique has evolved since its inception, enabling diverse applications in protein research. Notably, CRISPR/Cas9 gene editing has enhanced epitope tagging by enabling the tagging of endogenous genes, expanding its versatility. However, reproducibility challenges exist, demanding positive controls for troubleshooting. The pJoseph2 family of plasmids was developed to address this need, providing robust positive controls for various epitope-based experiments, from bacterial expression to Drosophila and mammalian cell studies. This resource enhances the reliability and accuracy of epitope tagging, benefiting researchers across disciplines.