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Sample records for reporter gene transfection

  1. Noninvasive imaging of transplanted living functional cells transfected with a reporter estrogen receptor gene

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    Takamatsu, Shinji [Biomedical Imaging Research Center, University of Fukui, 23-3 Shimoaizuki, Matsuoka, Yoshida, Fukui 910-1193 (Japan)]. E-mail: shinjit@fmsrsa.fukui-med.ac.jp; Furukawa, Takako [Biomedical Imaging Research Center, University of Fukui, 23-3 Shimoaizuki, Matsuoka, Yoshida, Fukui 910-1193 (Japan); Mori, Tetsuya [Biomedical Imaging Research Center, University of Fukui, 23-3 Shimoaizuki, Matsuoka, Yoshida, Fukui 910-1193 (Japan); Yonekura, Yoshiharu [Biomedical Imaging Research Center, University of Fukui, 23-3 Shimoaizuki, Matsuoka, Yoshida, Fukui 910-1193 (Japan); Fujibayashi, Yasuhisa [Biomedical Imaging Research Center, University of Fukui, 23-3 Shimoaizuki, Matsuoka, Yoshida, Fukui 910-1193 (Japan)

    2005-11-01

    The transplantation of functional cells such as dopaminergic cells into damaged tissue is now clinically ongoing, but at present the population of surviving cells at the transplantation site mostly cannot be noninvasively examined. To visualize surviving transplanted functional cells using a noninvasive method, we chose the estrogen receptor ligand binding domain (ERL) as a reporter molecule and 16{alpha}-[{sup 18}F]-fluoro-17{beta}-estradiol (FES) for its ligand. We used a mouse embryonic stem (ES) cell line for recipient cells as a model. To obtain ES cells that constitutively or inducibly express ERL, we transfected two types of expression vectors into EB5 parental ES cell line using the lipofection method and obtained about 30 clones for each of the two types of transfectants. Then, to examine the expression level of ERL, we performed Western blotting analysis. Ligand uptake experiments were carried out using [{sup 3}H]-estradiol with or without excessive unlabeled estradiol for control cells and ERL transfectants. Each selected clone was also used for in vivo positron emission tomography (PET) imaging studies involving FES in nude mice transplanted with control cells and ERL transfectants. In some of the clones transfected with the inducible-type ERL gene, protein was expressed much higher than in the controls. However, constitutive-type ERL gene-transfected ES cells showed no protein production in spite of their gene expression activity being considerably high. All clones also expressed equal levels of the Oct-3/4 gene, a marker of pluripotency, in comparison with the parental cells. Also, the specific uptake of [{sup 3}H]-estradiol was over 30 times higher in inducer-treated ERL-expressing ES cells compared to untreated control cells. Finally, by performing dynamic PET imaging, we successfully visualized ERL-expressing teratomas using FES.

  2. Noninvasive imaging of transplanted living functional cells transfected with a reporter estrogen receptor gene

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    Takamatsu, Shinji; Furukawa, Takako; Mori, Tetsuya; Yonekura, Yoshiharu; Fujibayashi, Yasuhisa

    2005-01-01

    The transplantation of functional cells such as dopaminergic cells into damaged tissue is now clinically ongoing, but at present the population of surviving cells at the transplantation site mostly cannot be noninvasively examined. To visualize surviving transplanted functional cells using a noninvasive method, we chose the estrogen receptor ligand binding domain (ERL) as a reporter molecule and 16α-[ 18 F]-fluoro-17β-estradiol (FES) for its ligand. We used a mouse embryonic stem (ES) cell line for recipient cells as a model. To obtain ES cells that constitutively or inducibly express ERL, we transfected two types of expression vectors into EB5 parental ES cell line using the lipofection method and obtained about 30 clones for each of the two types of transfectants. Then, to examine the expression level of ERL, we performed Western blotting analysis. Ligand uptake experiments were carried out using [ 3 H]-estradiol with or without excessive unlabeled estradiol for control cells and ERL transfectants. Each selected clone was also used for in vivo positron emission tomography (PET) imaging studies involving FES in nude mice transplanted with control cells and ERL transfectants. In some of the clones transfected with the inducible-type ERL gene, protein was expressed much higher than in the controls. However, constitutive-type ERL gene-transfected ES cells showed no protein production in spite of their gene expression activity being considerably high. All clones also expressed equal levels of the Oct-3/4 gene, a marker of pluripotency, in comparison with the parental cells. Also, the specific uptake of [ 3 H]-estradiol was over 30 times higher in inducer-treated ERL-expressing ES cells compared to untreated control cells. Finally, by performing dynamic PET imaging, we successfully visualized ERL-expressing teratomas using FES

  3. Green fluorescent protein (GFP color reporter gene visualizes parvovirus B19 non-structural segment 1 (NS1 transfected endothelial modification.

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    Thomas Wurster

    Full Text Available BACKGROUND: Human Parvovirus B19 (PVB19 has been associated with myocarditis putative due to endothelial infection. Whether PVB19 infects endothelial cells and causes a modification of endothelial function and inflammation and, thus, disturbance of microcirculation has not been elucidated and could not be visualized so far. METHODS AND FINDINGS: To examine the PVB19-induced endothelial modification, we used green fluorescent protein (GFP color reporter gene in the non-structural segment 1 (NS1 of PVB19. NS1-GFP-PVB19 or GFP plasmid as control were transfected in an endothelial-like cell line (ECV304. The endothelial surface expression of intercellular-adhesion molecule-1 (CD54/ICAM-1 and extracellular matrix metalloproteinase inducer (EMMPRIN/CD147 were evaluated by flow cytometry after NS-1-GFP or control-GFP transfection. To evaluate platelet adhesion on NS-1 transfected ECs, we performed a dynamic adhesion assay (flow chamber. NS-1 transfection causes endothelial activation and enhanced expression of ICAM-1 (CD54: mean ± standard deviation: NS1-GFP vs. control-GFP: 85.3 ± 11.2 vs. 61.6 ± 8.1; P<0.05 and induces endothelial expression of EMMPRIN/CD147 (CD147: mean ± SEM: NS1-GFP vs. control-GFP: 114 ± 15.3 vs. 80 ± 0.91; P<0.05 compared to control-GFP transfected cells. Dynamic adhesion assays showed that adhesion of platelets is significantly enhanced on NS1 transfected ECs when compared to control-GFP (P<0.05. The transfection of ECs was verified simultaneously through flow cytometry, immunofluorescence microscopy and polymerase chain reaction (PCR analysis. CONCLUSIONS: GFP color reporter gene shows transfection of ECs and may help to visualize NS1-PVB19 induced endothelial activation and platelet adhesion as well as an enhanced monocyte adhesion directly, providing in vitro evidence of possible microcirculatory dysfunction in PVB19-induced myocarditis and, thus, myocardial tissue damage.

  4. Inducement of radionuclides targeting therapy by gene transfection

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    Luo Quanyong

    2001-01-01

    The author presents an overview of gene transfection methods to genetically induce tumor cells to express enhanced levels of cell surface antigens and receptors to intake radiolabeled antibody and peptide targeting and thus increase their therapeutic effect in radiotherapy. The current research include inducement of radioimmunotherapy through CEA gene transfection, inducement of iodine-131 therapy by sodium iodide symporter gene transfection and inducement of MIBG therapy by noradrenaline transporter gene transfection. These studies raise the prospect that gene-therapy techniques could be used to enable the treatment of a wide range of tumors with radiopharmaceuticals of established clinical acceptability

  5. Enhanced transfection by antioxidative polymeric gene carrier that reduces polyplex-mediated cellular oxidative stress.

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    Lee, Min Sang; Kim, Nak Won; Lee, Kyuri; Kim, Hongtae; Jeong, Ji Hoon

    2013-06-01

    To test the hypothesis in which polyplex-induced oxidative stress may affect overall transfection efficiency, an antioxidative transfection system minimizing cellular oxidative stress was designed for enhanced transfection. An amphiphilic copolymer (PEI-PLGA) was synthesized and used as a micelle-type gene carrier containing hydrophobic antioxidant, α-tocopherol. Cellular oxidative stress and the change of mitochondrial membrane potential after transfection was measured by using a fluorescent probe (H₂DCFDA) and lipophilic cationic probe (JC-1), respectively. Transfection efficiency was determined by measuring a reporter gene (luciferase) expression level. The initial transfection study with conventional PEI/plasmid DNA polyplex showed significant generation of reactive oxygen species (ROS). The PEI-PLGA copolymer successfully carried out the simultaneous delivery of α-tocopherol and plasmid DNA (PEI-PLGA/Toco/pDNA polyplex) into cells, resulting in a significant reduction in cellular ROS generation after transfection and helped to maintain the mitochondrial membrane potential (ΔΨ). In addition, the transfection efficiency was dramatically increased using the antioxidative transfection system. This work showed that oxidative stress would be one of the important factors that should be considered in designing non-viral gene carriers and suggested a possible way to reduce the carrier-mediated oxidative stress, which consequently leads to enhanced transfection.

  6. Comparison of [{sup 18}F]FHBG and [{sup 14}C]FIAU for imaging of HSV1-tk reporter gene expression: adenoviral infection vs stable transfection

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    Min, Jung-Jun; Iyer, Meera [The Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, UCLA School of Medicine, B3-399A BRI 700 Westwood Plaza, CA 90095-1770, Los Angeles (United States); Gambhir, Sanjiv S. [The Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, UCLA School of Medicine, B3-399A BRI 700 Westwood Plaza, CA 90095-1770, Los Angeles (United States); Department of Radiology, Bio-X Program, Stanford University, Stanford, California (United States)

    2003-11-01

    Earlier studies involving comparison of different reporter probes have shown conflicting results between pyrimidine nucleosides [e.g., 2'-fluoro-2'-deoxy-1-{beta}-d-arabinofuranosyl-5-iodouracil (FIAU)] and acycloguanosine derivatives [e.g., penciclovir (PCV), 9-(4-fluoro-3-hydroxymethylbutyl)guanine (FHBG)]. We hypothesized that this reported discrepancy may be related to how the reporter gene is delivered to the cells - stably transfected vs adenoviral infection. We directly compared the uptake characteristics of [{sup 18}F]FHBG, [{sup 3}H]PCV, and [{sup 14}C]FIAU in cell culture and in vivo using an adenoviral mediated gene transfer model and stably transfected cells. We further compared the uptake of three reporter probes using both HSV1-tk and a mutant HSV1-sr39tk expressing cells to assess the optimal reporter probe/reporter gene combination. [{sup 14}C]FIAU accumulation was greater than that of [{sup 3}H]PCV and [{sup 18}F]FHBG in control cells and in HSV1-tk stably transfected cells (P<0.001). After infection of C6 cells with AdCMV-HSV1-tk (1.5 x 10{sup 8} pfu), [{sup 18}F]FHBG and [{sup 3}H]PCV accumulation was significantly greater than that of [{sup 14}C]FIAU (P<0.01). [{sup 18}F]FHBG and [{sup 3}H]PCV accumulated to a significantly greater extent than [{sup 14}C]FIAU in C6-stb-sr39tk+ and AdCMV-HSV1-sr39tk infected C6 cells (P<0.001). Results from the nude mice supported the results in cell culture. [{sup 14}C]FIAU led to significantly higher %ID/g in C6-stb-tk+ xenografts than [{sup 18}F]FHBG (P<0.05); however, compared with [{sup 14}C]FIAU, [{sup 18}F]FHBG led to as high %ID/g in HSV1-tk expressing hepatocytes and to significantly greater %ID/g in C6-stb-sr39tk+ xenografts and HSV1-sr39tk expressing hepatocytes. Dynamic sequential images showed that [{sup 18}F]FHBG was well retained in HSV1-sr39tk expressing cells (C6-stb-sr39tk+) for at least 4 h after injection, while it was rapidly cleared from HSV1-tk expressing cells (MH3924A

  7. Spontaneous gene transfection of human bone cells using 3D mineralized alginate-chitosan macrocapsules.

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    Green, David W; Kim, Eun-Jung; Jung, Han-Sung

    2015-09-01

    The effectiveness of nonviral gene therapy remains uncertain because of low transfection efficiencies and high toxicities compared with viral-based strategies. We describe a simple system for transient transfection of continuous human cell lines, with low toxicity, using mineral-coated chitosan and alginate capsules. As proof-of-concept, we demonstrate transfection of Saos-2 and MG63 human osteosarcoma continuous cell lines with gfp, LacZ reporter genes, and a Sox-9 carrying plasmid, to illustrate expression of a functional gene with therapeutic relevance. We show that continuous cell lines transfect with significant efficiency of up to 65% possibly through the interplay between chitosan and DNA complexation and calcium/phosphate-induced translocation into cells entrapped within the 3D polysaccharide based environment, as evidenced by an absence of transfection in unmineralized and chitosan-free capsules. We demonstrated that our transfection system was equally effective at transfection of primary human bone marrow stromal cells. To illustrate, the Sox-9, DNA plasmid was spontaneously expressed in primary human bone marrow stromal cells at 7 days with up to 90% efficiency in two repeats. Mineralized polysaccharide macrocapsules are gene delivery vehicles with a number of biological and practical advantages. They are highly efficient at self-transfecting primary bone cells, with programmable spatial and temporal delivery prospects, premineralized bone-like environments, and have no cytotoxic effects, as compared with many other nonviral systems. © 2015 Wiley Periodicals, Inc.

  8. Highly Effective Gene Transfection In Vivo by Alkylated Polyethylenimine

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    Jennifer A. Fortune

    2011-01-01

    Full Text Available We mechanistically explored the effect of increased hydrophobicity of the polycation on the efficacy and specificity of gene delivery in mice. N-Alkylated linear PEIs with varying alkyl chain lengths and extent of substitution were synthesized and characterized by biophysical methods. Their in vivo transfection efficiency, specificity, and biodistribution were investigated. N-Ethylation improves the in vivo efficacy of gene expression in the mouse lung 26-fold relative to the parent polycation and more than quadruples the ratio of expression in the lung to that in all other organs. N-Propyl-PEI was the best performer in the liver and heart (581- and 3.5-fold enhancements, resp. while N-octyl-PEI improved expression in the kidneys over the parent polymer 221-fold. As these enhancements in gene expression occur without changing the plasmid biodistribution, alkylation does not alter the cellular uptake but rather enhances transfection subsequent to cellular uptake.

  9. Towards gene therapy based on femtosecond optical transfection

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    Antkowiak, M.; Torres-Mapa, M. L.; McGinty, J.; Chahine, M.; Bugeon, L.; Rose, A.; Finn, A.; Moleirinho, S.; Okuse, K.; Dallman, M.; French, P.; Harding, S. E.; Reynolds, P.; Gunn-Moore, F.; Dholakia, K.

    2012-06-01

    Gene therapy poses a great promise in treatment and prevention of a variety of diseases. However, crucial to studying and the development of this therapeutic approach is a reliable and efficient technique of gene and drug delivery into primary cell types. These cells, freshly derived from an organ or tissue, mimic more closely the in vivo state and present more physiologically relevant information compared to cultured cell lines. However, primary cells are known to be difficult to transfect and are typically transfected using viral methods, which are not only questionable in the context of an in vivo application but rely on time consuming vector construction and may also result in cell de-differentiation and loss of functionality. At the same time, well established non-viral methods do not guarantee satisfactory efficiency and viability. Recently, optical laser mediated poration of cell membrane has received interest as a viable gene and drug delivery technique. It has been shown to deliver a variety of biomolecules and genes into cultured mammalian cells; however, its applicability to primary cells remains to be proven. We demonstrate how optical transfection can be an enabling technique in research areas, such as neuropathic pain, neurodegenerative diseases, heart failure and immune or inflammatory-related diseases. Several primary cell types are used in this study, namely cardiomyocytes, dendritic cells, and neurons. We present our recent progress in optimizing this technique's efficiency and post-treatment cell viability for these types of cells and discuss future directions towards in vivo applications.

  10. Ultrasonic destruction of albumin microbubbles enhances gene transfection and expression in cardiac myocytes.

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    Wang, Guo-zhong; Liu, Jing-hua; Lü, Shu-zheng; Lü, Yun; Guo, Cheng-jun; Zhao, Dong-hui; Fang, Dong-ping; He, Dong-fang; Zhou, Yuan; Ge, Chang-jiang

    2011-05-01

    It has been proven that ultrasonic destruction of microbubbles can enhance gene transfection efficiency into the noncardiac cells, but there are few reports about cardiac myocytes. Moreover, the exact mechanisms are not yet clear; whether the characteristic of microbubbles can affect the gene transfection efficiency or not is still controversial. This study was designed to investigate whether the ultrasound destruction of gene-loaded microbubbles could enhance the plasmids carried reporter gene transfection in primary cultured myocardial cell, and evaluate the effects of microbubbles characteristics on the transgene expression in cardiac myocytes. The β-galactosidase plasmids attached to the two types of microbubbles, air-contained sonicated dextrose albumin (ASDA) and perfluoropropane-exposed sonicated dextrose albumin (PESDA) were prepared. The gene transfection into cardiac myocytes was performed in vitro by naked plasmids, ultrasound exposure, ultrasonic destruction of gene-loaded microbubbles and calcium phosphate precipitation, and then the gene expression and cell viability were analyzed. The ultrasonic destruction of gene-loaded microbubbles enhanced gene expression in cardiac myocytes compared with naked plasmid transfection ((51.95 ± 2.41) U/g or (29.28 ± 3.65) U/g vs. (0.84 ± 0.21) U/g, P ASDA ((51.95 ± 2.41) U/g vs. (29.28 ± 3.65) U/g, P < 0.05). Ultrasonic destruction of microbubbles during calcium phosphate precipitation gene transfection enhanced β-galactosidase activity nearly 8-fold compared with calcium phosphate precipitation gene transfection alone ((111.35 ± 11.21) U/g protein vs. (14.13 ± 2.58) U/g protein, P < 0.01). Even 6 hours after calcium phosphate precipitation gene transfection, ultrasound-mediated microbubbles destruction resulted in more intense gene expression ((35.63 ± 7.65) U/g vs. (14.13 ± 2.58) U/g, P < 0.05). Ultrasonic destruction of microbubbles might be a promising method for the delivery of non-viral DNA into

  11. Conceptual and technical aspects of transfection and gene delivery.

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    Kaestner, Lars; Scholz, Anke; Lipp, Peter

    2015-03-15

    Genetically modified animals are state of the art in biomedical research as gene therapy is a promising perspective in the attempt to cure hereditary diseases. Both approaches have in common that modified or corrected genetic information must be transferred into cells in general or into particular cell types of an organism. Here we give an overview of established and emerging methods of transfection and gene delivery and provide conceptual and technical advantages and drawbacks of their particular use. Additionally, based on a flow chart, we compiled a rough guideline to choose a gene transfer method for a particular field of application. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Multi-lipofection efficiently transfected genes into astrocytes in primary culture.

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    Wu, B Y; Liu, R Y; So, K L; Yu, A C

    2000-10-30

    This study demonstrated that liposome-mediated transfection - lipofection - is suitable for delivering genes into astrocytes. By repeatedly lipofecting the same astrocyte cultures, a process we call multi-lipofection, the transfection efficiency of the beta-galactosidase (beta-gal) gene was improved from 2.6+/-0.6 to 17. 4+/-1.1%. This is the highest efficiency ever reported in gene-transfer with Lipofectin(R) in a primary culture of mouse cerebral cortical astrocytes. Furthermore, multi-lipofection did not cause observable disturbance to astrocytes as indicated by insignificant changes in the glial fibrillary acidic protein content in the cultures. In order to demonstrate that the transfected gene achieved a physiologically relevant expression level, a plasmid containing the pEF-hsp70 protein gene was lipofected into astrocytes. This produced colonies of astrocytes showing an increased resistance to heat-induced cell death. A similar experiment was performed with the glial-derived neurotrophic factor (GDNF) gene. Control astrocytes had no detectable GDNF. In the transfected astrocytes, the GDNF protein could be identified intracellularly by immunocytochemistry. Western blot analysis revealed, as compared to astrocytes with one lipofection, a 2.9-fold increase of GDNF with four lipofections. GDNF remained detectable in astrocytes 2 weeks after four lipofections. Thus, multi-lipofection provides a mild and efficient means of delivering foreign genes into astrocytes in a primary culture, making astrocytes good candidate vehicle cells for gene/cell therapy in the CNS.

  13. Repeated Gene Transfection Impairs the Engraftment of Transplanted Porcine Neonatal Pancreatic Cells

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    Min Koo Seo

    2011-02-01

    Full Text Available BackgroundPreviously, we reported that neonatal porcine pancreatic cells transfected with hepatocyte growth factor (HGF gene in an Epstein-Barr virus (EBV-based plasmid (pEBVHGF showed improved proliferation and differentiation compared to those of the control. In this study, we examined if pancreatic cells transfected repeatedly with pEBVHGF can be successfully grafted to control blood glucose in a diabetes mouse model.MethodsNeonatal porcine pancreatic cells were cultured as a monolayer and were transfected with pEBVHGF every other day for a total of three transfections. The transfected pancreatic cells were re-aggregated and transplanted into kidney capsules of diabetic nude mice or normal nude mice. Blood glucose level and body weight were measured every other day after transplantation. The engraftment of the transplanted cells and differentiation into beta cells were assessed using immunohistochemistry.ResultsRe-aggregation of the pancreatic cells before transplantation improved engraftment of the cells and facilitated neovascularization of the graft. Right before transplantation, pancreatic cells that were transfected with pEBVHGF and then re-aggregated showed ductal cell marker expression. However, ductal cells disappeared and the cells underwent fibrosis in a diabetes mouse model two to five weeks after transplantation; these mice also did not show controlled blood glucose levels. Furthermore, pancreatic cells transplanted into nude mice with normal blood glucose showed poor graft survival regardless of the type of transfected plasmid (pCEP4, pHGF, or pEBVHGF.ConclusionFor clinical application of transfected neonatal porcine pancreatic cells, further studies are required to develop methods of overcoming the damage for the cells caused by repeated transfection and to re-aggregate them into islet-like structures.

  14. Tissue Engineering Using Transfected Growth-Factor Genes

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    Madry, Henning; Langer, Robert S.; Freed, Lisa E.; Trippel, Stephen; Vunjak-Novakovic, Gordana

    2005-01-01

    A method of growing bioengineered tissues includes, as a major component, the use of mammalian cells that have been transfected with genes for secretion of regulator and growth-factor substances. In a typical application, one either seeds the cells onto an artificial matrix made of a synthetic or natural biocompatible material, or else one cultures the cells until they secrete a desired amount of an extracellular matrix. If such a bioengineered tissue construct is to be used for surgical replacement of injured tissue, then the cells should preferably be the patient s own cells or, if not, at least cells matched to the patient s cells according to a human-leucocyteantigen (HLA) test. The bioengineered tissue construct is typically implanted in the patient's injured natural tissue, wherein the growth-factor genes enhance metabolic functions that promote the in vitro development of functional tissue constructs and their integration with native tissues. If the matrix is biodegradable, then one of the results of metabolism could be absorption of the matrix and replacement of the matrix with tissue formed at least partly by the transfected cells. The method was developed for articular chondrocytes but can (at least in principle) be extended to a variety of cell types and biocompatible matrix materials, including ones that have been exploited in prior tissue-engineering methods. Examples of cell types include chondrocytes, hepatocytes, islet cells, nerve cells, muscle cells, other organ cells, bone- and cartilage-forming cells, epithelial and endothelial cells, connective- tissue stem cells, mesodermal stem cells, and cells of the liver and the pancreas. Cells can be obtained from cell-line cultures, biopsies, and tissue banks. Genes, molecules, or nucleic acids that secrete factors that influence the growth of cells, the production of extracellular matrix material, and other cell functions can be inserted in cells by any of a variety of standard transfection techniques.

  15. Lipoplex morphologies and their influences on transfection efficiency in gene delivery.

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    Ma, Baichao; Zhang, Shubiao; Jiang, Huiming; Zhao, Budiao; Lv, Hongtao

    2007-11-20

    Cationic lipid-mediated gene transfer is widely used for their advantages over viral gene transfer because it is non-immunogenic, easy to produce and not oncogenic. The main drawback of the application of cationic lipids is their low transfection efficiency. Many reports about transfection efficiency of cationic lipids have been published in recent years. In this review, the current status and prospects for transfection efficiency of different morphologies of lipoplexes are discussed. High transfection activity will be acquired for H(C)(II) structure when membrane fusion is dominant, but when serum is present L(C)(alpha) lipoplexes show great superiority for their inhibition dissociation by serum during lipoplexes transporting. Increasing DOPE often gains high activity for the H(C)(II) structure promoted by DOPE. High lipofection will be gained from large lipoplexes when endocytosis is dominant, because large particles facilitate membrane contact and fusion. We suggest morphologies of lipoplex should be characterized at two levels, lipoplex size and self-assemble structures of lipoplexes, and understanding these would be very important for scientists to prepare novel cationic lipids and design novel formulations with high transfection efficiency.

  16. Transferrin-facilitated lipofection gene delivery strategy: characterization of the transfection complexes and intracellular trafficking.

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    Joshee, Nirmal; Bastola, Dhundy R; Cheng, Pi-Wan

    2002-11-01

    We previously showed that mixing transferrin with a cationic liposome prior to the addition of DNA, greatly enhanced the lipofection efficiency. Here, we report characterization of the transfection complexes in formulations prepared with transferrin, lipofectin, and DNA (pCMVlacZ) in various formulations. DNA in all the formulations that contain lipofectin was resistant to DNase I treatment. Transfection experiments performed in Panc 1 cells showed that the standard formulation, which was prepared by adding DNA to a mixture of transferrin and lipofectin, yielded highest transfection efficiency. There was no apparent difference in zeta potential among these formulations, but the most efficient formulation contained complexes with a mean diameter of three to four times that of liposome and the complexes in other gene delivery formulations. Transmission electron microscopic examination of the standard transfection complexes formulated using gold-labeled transferrin showed extended circular DNA decorated with transferrin as compared to extensively condensed DNA found in lipofectin-DNA complexes and heterogeneous structures in other formulations. By confocal microscopy, DNA and transferrin were found to colocalize at the perinuclear space and in the nucleus, suggesting cotransportation intracellularly, including nuclear transport. We propose that transferrin enhances the transfection efficiency of the standard lipofection formulation by preventing DNA condensation, and facilitating endocytosis and nuclear targeting.

  17. Non-Viral Transfection Methods Optimized for Gene Delivery to a Lung Cancer Cell Line

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    Salimzadeh, Loghman; Jaberipour, Mansooreh; Hosseini, Ahmad; Ghaderi, Abbas

    2013-01-01

    Background Mehr-80 is a newly established adherent human large cell lung cancer cell line that has not been transfected until now. This study aims to define the optimal transfection conditions and effects of some critical elements for enhancing gene delivery to this cell line by utilizing different non-viral transfection Procedures. Methods In the current study, calcium phosphate (CaP), DEAE-dextran, superfect, electroporation and lipofection transfection methods were used to optimize deliver...

  18. Amiloride-enhanced gene transfection of octa-arginine functionalized calcium phosphate nanoparticles.

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    Juan Ramón Vanegas Sáenz

    Full Text Available Nanoparticles represent promising gene delivery systems in biomedicine to facilitate prolonged gene expression with low toxicity compared to viral vectors. Specifically, nanoparticles of calcium phosphate (nCaP, the main inorganic component of human bone, exhibit high biocompatibility and good biodegradability and have been reported to have high affinity for protein or DNA, having thus been used as gene transfer vectors. On the other hand, Octa-arginine (R8, which has a high permeability to cell membrane, has been reported to improve intracellular delivery systems. Here, we present an optimized method for nCaP-mediated gene delivery using an octa-arginine (R8-functionalized nCaP vector containing a marker or functional gene construct. nCaP particle size was between 220-580 nm in diameter and all R8-functionalized nCaPs carried a positive charge. R8 concentration significantly improved nCaP transfection efficiency with high cell compatibility in human mesenchymal stem cells (hMSC and human osteoblasts (hOB in particular, suggesting nCaPs as a good option for non-viral vector gene delivery. Furthermore, pre-treatment with different endocytosis inhibitors identified that the endocytic pathway differed among cell lines and functionalized nanoparticles, with amiloride increasing transfection efficiency of R8-functionalized nCaPs in hMSC and hOB.

  19. Non-viral genetic transfection of rat Schwann cells with FuGENE HD© lipofection and AMAXA© nucleofection is feasible but impairs cell viability.

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    Kraus, Armin; Täger, Joachim; Kohler, Konrad; Haerle, Max; Werdin, Frank; Schaller, Hans-Eberhard; Sinis, Nektarios

    2010-11-01

    To determine transfection efficiency of FuGENE HD© lipofection and AMAXA© nucleofection on rat Schwann cells (SC). The ischiadic and median nerves of 6-8 week old Lewis rats were cultured in modified melanocyte-growth medium. SCs were genetically transfected with green fluorescent protein (GFP) as reporter gene using FuGENE HD© lipofection and AMAXA© nucleofection. Transfection rates were determined by visualization of GFP fluorescence under fluorescence microscopy and cell counting. Transfected cell to non-transfected cell relation was determined. Purity of Schwann cell culture was 88% as determined by immunohistologic staining. Transfection rate of FuGENE HD© lipofection was 2%, transfection rate of AMAXA© nucleofection was 10%. With both methods, Schwann cells showed pronounced aggregation behavior which made them unfeasible for further cultivation. Settling of Schwann cells on laminin and poly-L-ornithine coated plates was compromised by either method. Non-viral transfection of rat SC with FuGENE HD© lipofection and AMAXA© nucleofection is basically possible with a higher transfection rate for nucleofection than for lipofection. As cell viability is compromised by either method however, viral transfection is to be considered if higher efficiency is required.

  20. Membrane fusion inducers, chloroquine and spermidine increase lipoplex-mediated gene transfection

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    Wong-Baeza, Carlos; Bustos, Israel; Serna, Manuel; Tescucano, Alonso; Alcantara-Farfan, Veronica; Ibanez, Miguel; Montanez, Cecilia; Wong, Carlos; Baeza, Isabel

    2010-01-01

    Gene transfection into mammalian cells can be achieved with viral and non-viral vectors. Non-viral vectors, such as cationic lipids that form lipoplexes with DNA, are safer and more stable than viral vectors, but their transfection efficiencies are lower. Here we describe that the simultaneous treatment with a membrane fusion inducer (chlorpromazine or procainamide) plus the lysosomotropic agent chloroquine increases lipoplex-mediated gene transfection in human (HEK293 and C-33 A) and rat (PC12) cell lines (up to 9.2-fold), as well as in situ in BALB/c mice spleens and livers (up to 6-fold); and that the polyamine spermidine increases lipoplex-mediated gene transfection and expression in cell cultures. The use of these four drugs provides a novel, safe and relatively inexpensive way to considerably increase lipoplex-mediated gene transfection efficiency.

  1. Evaluation of the magnetic field requirements for nanomagnetic gene transfection

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    Fouriki, A.; Farrow, N.; Clements, M.A.; Dobson, J.

    2010-01-01

    The objective of this work was to examine the effects of magnet distance (and by proxy, field strength) on nanomagnetic transfection efficiency. Methods non-viral magnetic nanoparticle-based transfection was evaluated using both static and oscillating magnet arrays. Results Fluorescence intensity (firefly luciferase) of transfected H292 cells showed no increase using a 96-well NdFeB magnet array when the magnets were 5 mm from the cell culture plate or nearer. At 6 mm and higher, fluorescence intensity decreased systematically. Conclusion In all cases, fluorescence intensity was higher when using an oscillating array compared to a static array. For distances closer than 5 mm, the oscillating system also outperformed Lipofectamine 2000™. PMID:22110859

  2. Evaluation of the magnetic field requirements for nanomagnetic gene transfection

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    A. Fouriki

    2010-07-01

    Full Text Available The objective of this work was to examine the effects of magnet distance (and by proxy, field strength on nanomagnetic transfection efficiency. Methods: non-viral magnetic nanoparticle-based transfection was evaluated using both static and oscillating magnet arrays. Results: Fluorescence intensity (firefly luciferase of transfected H292 cells showed no increase using a 96-well NdFeB magnet array when the magnets were 5 mm from the cell culture plate or nearer. At 6 mm and higher, fluorescence intensity decreased systematically. Conclusion: In all cases, fluorescence intensity was higher when using an oscillating array compared to a static array. For distances closer than 5 mm, the oscillating system also outperformed Lipofectamine 2000™.

  3. Non-Viral Transfection Methods Optimized for Gene Delivery to a Lung Cancer Cell Line

    Science.gov (United States)

    Salimzadeh, Loghman; Jaberipour, Mansooreh; Hosseini, Ahmad; Ghaderi, Abbas

    2013-01-01

    Background Mehr-80 is a newly established adherent human large cell lung cancer cell line that has not been transfected until now. This study aims to define the optimal transfection conditions and effects of some critical elements for enhancing gene delivery to this cell line by utilizing different non-viral transfection Procedures. Methods In the current study, calcium phosphate (CaP), DEAE-dextran, superfect, electroporation and lipofection transfection methods were used to optimize delivery of a plasmid construct that expressed Green Fluorescent Protein (GFP). Transgene expression was detected by fluorescent microscopy and flowcytometry. Toxicities of the methods were estimated by trypan blue staining. In order to evaluate the density of the transfected gene, we used a plasmid construct that expressed the Stromal cell-Derived Factor-1 (SDF-1) gene and measured its expression by real-time PCR. Results Mean levels of GFP-expressing cells 48 hr after transfection were 8.4% (CaP), 8.2% (DEAE-dextran), 4.9% (superfect), 34.1% (electroporation), and 40.1% (lipofection). Lipofection had the highest intense SDF-1 expression of the analyzed methods. Conclusion This study has shown that the lipofection and electroporation methods were more efficient at gene delivery to Mehr-80 cells. The quantity of DNA per transfection, reagent concentration, and incubation time were identified as essential factors for successful transfection in all of the studied methods. PMID:23799175

  4. Non-viral transfection methods optimized for gene delivery to a lung cancer cell line.

    Science.gov (United States)

    Salimzadeh, Loghman; Jaberipour, Mansooreh; Hosseini, Ahmad; Ghaderi, Abbas

    2013-04-01

    Mehr-80 is a newly established adherent human large cell lung cancer cell line that has not been transfected until now. This study aims to define the optimal transfection conditions and effects of some critical elements for enhancing gene delivery to this cell line by utilizing different non-viral transfection Procedures. In the current study, calcium phosphate (CaP), DEAE-dextran, superfect, electroporation and lipofection transfection methods were used to optimize delivery of a plasmid construct that expressed Green Fluorescent Protein (GFP). Transgene expression was detected by fluorescent microscopy and flowcytometry. Toxicities of the methods were estimated by trypan blue staining. In order to evaluate the density of the transfected gene, we used a plasmid construct that expressed the Stromal cell-Derived Factor-1 (SDF-1) gene and measured its expression by real-time PCR. Mean levels of GFP-expressing cells 48 hr after transfection were 8.4% (CaP), 8.2% (DEAE-dextran), 4.9% (superfect), 34.1% (electroporation), and 40.1% (lipofection). Lipofection had the highest intense SDF-1 expression of the analyzed methods. This study has shown that the lipofection and electroporation methods were more efficient at gene delivery to Mehr-80 cells. The quantity of DNA per transfection, reagent concentration, and incubation time were identified as essential factors for successful transfection in all of the studied methods.

  5. Ultrasound-mediated vascular gene transfection by cavitation of endothelial-targeted cationic microbubbles.

    Science.gov (United States)

    Xie, Aris; Belcik, Todd; Qi, Yue; Morgan, Terry K; Champaneri, Shivam A; Taylor, Sarah; Davidson, Brian P; Zhao, Yan; Klibanov, Alexander L; Kuliszewski, Michael A; Leong-Poi, Howard; Ammi, Azzdine; Lindner, Jonathan R

    2012-12-01

    Ultrasound-mediated gene delivery can be amplified by acoustic disruption of microbubble carriers that undergo cavitation. We hypothesized that endothelial targeting of microbubbles bearing cDNA is feasible and, through optimizing proximity to the vessel wall, increases the efficacy of gene transfection. Contrast ultrasound-mediated gene delivery is a promising approach for site-specific gene therapy, although there are concerns with the reproducibility of this technique and the safety when using high-power ultrasound. Cationic lipid-shelled decafluorobutane microbubbles bearing a targeting moiety were prepared and compared with nontargeted microbubbles. Microbubble targeting efficiency to endothelial adhesion molecules (P-selectin or intercellular adhesion molecule [ICAM]-1) was tested using in vitro flow chamber studies, intravital microscopy of tumor necrosis factor-alpha (TNF-α)-stimulated murine cremaster muscle, and targeted contrast ultrasound imaging of P-selectin in a model of murine limb ischemia. Ultrasound-mediated transfection of luciferase reporter plasmid charge coupled to microbubbles in the post-ischemic hindlimb muscle was assessed by in vivo optical imaging. Charge coupling of cDNA to the microbubble surface was not influenced by the presence of targeting ligand, and did not alter the cavitation properties of cationic microbubbles. In flow chamber studies, surface conjugation of cDNA did not affect attachment of targeted microbubbles at microvascular shear stresses (0.6 and 1.5 dyne/cm(2)). Attachment in vivo was also not affected by cDNA according to intravital microscopy observations of venular adhesion of ICAM-1-targeted microbubbles and by ultrasound molecular imaging of P-selectin-targeted microbubbles in the post-ischemic hindlimb in mice. Transfection at the site of high acoustic pressures (1.0 and 1.8 MPa) was similar for control and P-selectin-targeted microbubbles but was associated with vascular rupture and hemorrhage. At 0.6 MPa

  6. Effect of albumin and dextrose concentration on ultrasound and microbubble mediated gene transfection in vivo.

    Science.gov (United States)

    Browning, Richard J; Mulvana, Helen; Tang, Meng-Xing; Hajnal, Jo V; Wells, Dominic J; Eckersley, Robert J

    2012-06-01

    Ultrasound and microbubble mediated gene transfection has great potential for site-selective, safe gene delivery. Albumin-based microbubbles have shown the greatest transfection efficiency but have not been optimised specifically for this purpose. Additionally, few studies have highlighted desirable properties for transfection specific microbubbles. In this article, microbubbles were made with 2% or 5% (w/v) albumin and 20% or 40% (w/v) dextrose solutions, yielding four distinct bubble types. These were acoustically characterised and their efficiency in transfecting a luciferase plasmid (pGL4.13) into female, CD1 mice myocardia was measured. For either albumin concentration, increasing the dextrose concentration increased scattering, attenuation and resistance to ultrasound, resulting in significantly increased transfection. A significant interaction was noted between albumin and dextrose; 2% albumin bubbles made with 20% dextrose showed the least transfection but the most transfection with 40% dextrose. This trend was seen for both nonlinear scattering and attenuation behaviour but not for resistance to ultrasound or total scatter. We have determined that the attenuation behaviour is an important microbubble characteristic for effective gene transfection using ultrasound. Microbubble behaviour can also be simply controlled by altering the initial ingredients used during manufacture. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Liposome-based DNA carriers may induce cellular stress response and change gene expression pattern in transfected cells

    Science.gov (United States)

    2011-01-01

    Background During functional studies on the rat stress-inducible Hspa1b (hsp70.1) gene we noticed that some liposome-based DNA carriers, which are used for transfection, induce its promoter activity. This observation concerned commercial liposome formulations (LA), Lipofectin and Lipofectamine 2000. This work was aimed to understand better the mechanism of this phenomenon and its potential biological and practical consequences. Results We found that a reporter gene driven by Hspa1b promoter is activated both in the case of transient transfections and in the stably transfected cells treated with LA. Using several deletion clones containing different fragments of Hspa1b promoter, we found that the regulatory elements responsible for most efficient LA-driven inducibility were located between nucleotides -269 and +85, relative to the transcription start site. Further studies showed that the induction mechanism was independent of the classical HSE-HSF interaction that is responsible for gene activation during heat stress. Using DNA microarrays we also detected significant activation of the endogenous Hspa1b gene in cells treated with Lipofectamine 2000. Several other stress genes were also induced, along with numerous genes involved in cellular metabolism, cell cycle control and pro-apoptotic pathways. Conclusions Our observations suggest that i) some cationic liposomes may not be suitable for functional studies on hsp promoters, ii) lipofection may cause unintended changes in global gene expression in the transfected cells. PMID:21663599

  8. Liposome-based DNA carriers may induce cellular stress response and change gene expression pattern in transfected cells

    Directory of Open Access Journals (Sweden)

    Lisowska Katarzyna Marta

    2011-06-01

    Full Text Available Abstract Background During functional studies on the rat stress-inducible Hspa1b (hsp70.1 gene we noticed that some liposome-based DNA carriers, which are used for transfection, induce its promoter activity. This observation concerned commercial liposome formulations (LA, Lipofectin and Lipofectamine 2000. This work was aimed to understand better the mechanism of this phenomenon and its potential biological and practical consequences. Results We found that a reporter gene driven by Hspa1b promoter is activated both in the case of transient transfections and in the stably transfected cells treated with LA. Using several deletion clones containing different fragments of Hspa1b promoter, we found that the regulatory elements responsible for most efficient LA-driven inducibility were located between nucleotides -269 and +85, relative to the transcription start site. Further studies showed that the induction mechanism was independent of the classical HSE-HSF interaction that is responsible for gene activation during heat stress. Using DNA microarrays we also detected significant activation of the endogenous Hspa1b gene in cells treated with Lipofectamine 2000. Several other stress genes were also induced, along with numerous genes involved in cellular metabolism, cell cycle control and pro-apoptotic pathways. Conclusions Our observations suggest that i some cationic liposomes may not be suitable for functional studies on hsp promoters, ii lipofection may cause unintended changes in global gene expression in the transfected cells.

  9. Plasmid DNA transfection using magnetite cationic liposomes for construction of multilayered gene-engineered cell sheet.

    Science.gov (United States)

    Ino, Kosuke; Kawasumi, Tamayo; Ito, Akira; Honda, Hiroyuki

    2008-05-01

    Modification of cellular functions by overexpression of genes is being increasingly practiced for tissue engineering. In the present study, we investigated whether transfection efficiency could be enhanced by magnetofection that involves the use of plasmid DNA (pDNA)/magnetite cationic liposomes (MCLs) complexes (pDNA/MCL) and magnetic force. The transfection efficiencies of the magnetofection technique by pDNA/MCL in fibroblasts and keratinocytes using reporter genes were 36- and 10-fold higher, respectively, than those of a lipofection technique by cationic liposomes. Moreover, in vitro construction of three-dimensional (3D) tissues is an important challenge. We recently proposed a novel technique termed "magnetic force-based tissue engineering" (Mag-TE) to produce 3D tissues. Since the fibroblasts after magnetofection incorporated both magnetite nanoparticles and pDNA, we investigated whether multilayered heterotypic cell sheets expressing transgene could be fabricated by Mag-TE. First, the fibroblasts were seeded onto an ultra-low attachment culture plate. When a magnet was placed under the plate, the cells accumulated at the bottom of the culture plate. After 24 h of culture, the transgene-expressing cells formed a multilayered cell sheet-like structure. These results indicated that MCLs are a potent biomanipulation tool for both gene transfer and 3D tissue construction, suggesting that these techniques are useful for tissue engineering. Copyright 2007 Wiley Periodicals, Inc.

  10. Improving ultrasound gene transfection efficiency by controlling ultrasound excitation of microbubbles

    Science.gov (United States)

    Fan, Z.; Chen, D.; Deng, C.X.

    2013-01-01

    Ultrasound application in the presence of microbubbles has shown great potential for non-viral gene transfection via transient disruption of cell membrane (sonoporation). However, improvement of its efficiency has largely relied on empirical approaches without consistent and translatable results. The goal of this study is to develop a rational strategy based on new results obtained using novel experimental techniques and analysis to improve sonoporation gene transfection. We conducted experiments using targeted microbubbles that were attached to cell membrane to facilitate sonoporation. We quantified the dynamic activities of microbubbles exposed to pulsed ultrasound and the resulting sonoporation outcome and identified distinct regimes of characteristic microbubble behaviors: stable cavitation, coalescence and translation, and inertial cavitation. We found that inertial cavitation generated the highest rate of membrane poration. By establishing direct correlation of ultrasound-induced bubble activities with intracellular uptake and pore size, we designed a ramped pulse exposure scheme for optimizing microbubble excitation to improve sonoporation gene transfection. We implemented a novel sonoporation gene transfection system using an aqueous two phase system (ATPS) for efficient use of reagents and high throughput operation. Using plasmid coding for the green fluorescence protein (GFP), we achieved a sonoporation transfection efficiency in rate aortic smooth muscle cells (RASMCs) of 6.9% ± 2.2% (n = 9), comparable with lipofection (7.5% ± 0.8%, n = 9). Our results reveal characteristic microbubble behaviors responsible for sonoporation and demonstrated a rational strategy to improve sonoporation gene transfection. PMID:23770009

  11. Gene Transfection Method Using Atmospheric Pressure Dielectric-Barrier Discharge Plasmas

    Science.gov (United States)

    Sasaki, Shota; Kanzaki, Makoto; Kaneko, Toshiro

    2013-09-01

    Gene transfection which is the process of deliberately introducing nucleic acids into cells is expected to play an important role in medical treatment because the process is necessary for gene therapy and creation of induced pluripotent stem (iPS) cells. However, the conventional transfection methods have some problems, so we focus attention on promising transfection methods by atmospheric pressure dielectric-barrier discharge (AP-DBD) plasmas. AP-DBD He plasmas are irradiated to the living cell covered with genes. Preliminarily, we use fluorescent dye YOYO-1 instead of the genes and use LIVE/DEAD Stain for cell viability test, and we analyze the transfection efficiency and cell viability under the various conditions. It is clarified that the transfection efficiency is strongly dependence on the plasma irradiation time and cell viability rates is high rates (>90%) regardless of long plasma irradiation time. These results suggest that ROS (Reactive Oxygen Species) and electric field generated by the plasma affect the gene transfection. In addition to this (the plasma irradiation time) dependency, we now investigate the effect of the plasma irradiation under the various conditions.

  12. Investigation of transfection efficacy with transcatheter arterial transporting transferring to enhance p53 gene

    International Nuclear Information System (INIS)

    Lu Qin; Niu Huanzhang; Zhu Guangyu; An Yanli; Qiu Dinghong; Teng Gaojun

    2007-01-01

    Objective: To investigate the function of transferrin-DNA complex, transported by transferrin(Tf) and trans-arterial injection via interventional approach be the duel-target-orientated delivery and the transferring into malignant cells to get more effective therapy. Methods: p53-LipofectAMINE ligand with different concentrations of Tf (0, 10, 25, 50, 100 μg)transfected the 4 strains including LM6,Hep3B,YY and L02 in vitro to evaluate the gene transfection efficiency through western blot. Then, after setting up the VX2 hepatocarcinoma models, we delivered the Tf-p53-LipofectAMlNE complex into the hepatic arteries via interventional techniques to analyse the transfection efficiency in vivo. Results: Tf, within the range of l0 100 μg, could increase gene transfection efficiency mediated by liposome, and the efficiency increases with the raise of Tf concentration. Combination with interventional technique to inject Tf-DNA complex into tumor arteries, gene transfection efficiency was enhanced in rabbit models. Conclusion: Tf can enhance gene-liposome transfection efficiency, furthermore with combination of interventional catheter technique, there would be a potential duel-target-orientated gene therapy method. (authors)

  13. Investigation of transfection efficacy with transcatheter arterial transporting transferring to enhance p53 gene

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Lu; Huanzhang, Niu; Guangyu, Zhu; Yanli, An; Dinghong, Qiu; Gaojun, Teng [Radiologic Department, Zhongda Hospital, Southeast Univ., Nanjing (China)

    2007-02-15

    Objective: To investigate the function of transferrin-DNA complex, transported by transferrin(Tf) and trans-arterial injection via interventional approach be the duel-target-orientated delivery and the transferring into malignant cells to get more effective therapy. Methods: p53-LipofectAMINE ligand with different concentrations of Tf (0, 10, 25, 50, 100 {mu}g)transfected the 4 strains including LM6,Hep3B,YY and L02 in vitro to evaluate the gene transfection efficiency through western blot. Then, after setting up the VX2 hepatocarcinoma models, we delivered the Tf-p53-LipofectAMlNE complex into the hepatic arteries via interventional techniques to analyse the transfection efficiency in vivo. Results: Tf, within the range of l0 100 {mu}g, could increase gene transfection efficiency mediated by liposome, and the efficiency increases with the raise of Tf concentration. Combination with interventional technique to inject Tf-DNA complex into tumor arteries, gene transfection efficiency was enhanced in rabbit models. Conclusion: Tf can enhance gene-liposome transfection efficiency, furthermore with combination of interventional catheter technique, there would be a potential duel-target-orientated gene therapy method. (authors)

  14. Effects of molecular size and chemical factor on plasma gene transfection

    Science.gov (United States)

    Ikeda, Yoshihisa; Motomura, Hideki; Kido, Yugo; Satoh, Susumu; Jinno, Masafumi

    2016-07-01

    In order to clarify the mechanism of plasma gene transfection, the relationship between transfection efficiency and transferred molecular size was investigated. Molecules with low molecular mass (less than 50 kDa; dye or dye-labeled oligonucleotide) and high molecular mass (more than 1 MDa; plasmid DNA or fragment of plasmid DNA) were transferred to L-929 cells. It was found that the transfection efficiency decreases with increasing in transferred molecular size and also depends on the tertiary structure of transferred molecules. Moreover, it was suggested the transfection mechanism is different between the molecules with low (less than 50 kDa) and high molecular mass (higher than 1 MDa). For the amount of gene transfection after plasma irradiation, which is comparable to that during plasma irradiation, it is shown that H2O2 molecules are the main contributor. The transfection efficiency decreased to 0.40 ± 0.22 upon scavenging the H2O2 generated by plasma irradiation using the catalase. On the other hand, when the H2O2 solution is dropped into the cell suspension without plasma irradiation, the transfection efficiency is almost 0%. In these results, it is also suggested that there is a synergetic effect of H2O2 with electrical factors or other reactive species generated by plasma irradiation.

  15. Guanidinylated polyethyleneimine-polyoxypropylene-polyoxyethylene conjugates as gene transfection agents.

    Science.gov (United States)

    Bromberg, Lev; Raduyk, Svetlana; Hatton, T Alan; Concheiro, Angel; Rodriguez-Valencia, Cosme; Silva, Maite; Alvarez-Lorenzo, Carmen

    2009-05-20

    Conjugates of linear and branched polyethyleneimine (PEI) and monoamine polyether Jeffamine M-2070 (PO/EO mol ratio 10/31, 2000 Da) were synthesized through polyether activation by cyanuric chloride followed by attachment to PEI and guanidinylation by 1H-pyrazole-carboxamidine hydrochloride. The resulting guanidinylated PEI-polyether conjugates (termed gPEI-Jeffamine) efficiently complexed plasmid DNA, and their polyplexes possessed enhanced colloidal stability in the presence of serum proteins. In vitro studies with mammalian CHO-1, 3T3, and Cos-7 cell lines demonstrated improved transfection efficiency of the pCMVbeta-gal plasmid/gPEI-Jeffamine polyplexes. The guanidinylation of the amino groups of PEI and the conjugation of PEI with the Jeffamine polyether enhanced the conjugates' interaction with genetic material and reduced the cytotoxicity of the polyplexes in experiments with the L929 cell line.

  16. Adipogenic differentiation and EGFP gene transfection of amniotic fluid-derived stem cells from goat fetus at terminal gestational age.

    Science.gov (United States)

    He, Xiao-Ying; Zheng, Yue-Mao; Qiu, Shuang; Qi, Ying-Pei; Zhang, Yong

    2011-08-01

    The aims of this study were to determine whether stem cells could be isolated from amniotic fluid of goat fetus at terminal gestational age and to determine if these stem cells could differentiate into adipogenic cells and be transfected with a reporter gene, EGFP (enhanced green fluorescent protein). The stem cells were isolated from amniotic fluid of goat fetus at terminal gestational age, induced to differentiate into adipogenic cells in vitro and transfected with the EGFP gene using lipofection. Markers associated with undifferentiated AFS (amniotic fluid-derived stem) cells were tested by RT (reverse transcription)-PCR. The results demonstrated that AFS cells could be isolated from amniotic fluid of goat fetus at terminal gestational age and could differentiate into adipogenic cells. The EGFP gene was transfected into AFS cells successfully. EGFP gene transfection efficiency of the three groups of transgenic AFS cells were 26.0, 29.9 and 30.5%, respectively. Both transgenic and wild-type AFS cells could express Hes1 (hairy and enhancer of split 1), Oct4 (octamer-binding protein 4) and Nanog.

  17. Ultrasound-mediated interferon β gene transfection inhibits growth of malignant melanoma

    International Nuclear Information System (INIS)

    Yamaguchi, Kazuki; Feril, Loreto B.; Tachibana, Katsuro; Takahashi, Akira; Matsuo, Miki; Endo, Hitomi; Harada, Yoshimi; Nakayama, Juichiro

    2011-01-01

    Highlights: → Successful ultrasound-mediated transfection of melanoma (C32) cells with IFN-β genes both in vitro and in vivo. → Ultrasound-mediated IFN-β transfection inhibited proliferation of melanoma cells in vitro. → Ultrasound-mediated IFN-β transfection inhibited melanoma tumor growth in vivo. -- Abstract: We investigated the effects of ultrasound-mediated transfection (sonotransfection) of interferon β (IFN-β) gene on melanoma (C32) both in vitro and in vivo. C32 cells were sonotransfected with IFN-β in vitro. Subcutaneous C32 tumors in mice were sonicated weekly immediately after intra-tumor injection with IFN-β genes mixed with microbubbles. Successful sonotransfection with IFN-β gene in vitro was confirmed by ELISA, which resulted in C32 growth inhibition. In vivo, the growth ratio of tumors transfected with IFN-β gene was significantly lower than the other experimental groups. These results may lead to a new method of treatment against melanoma and other hard-to-treat cancers.

  18. Transfection of small RNAs globally perturbs gene regulation by endogenous microRNAs

    DEFF Research Database (Denmark)

    Khan, Aly A; Betel, Doron; Miller, Martin L

    2009-01-01

    Transfection of small RNAs (such as small interfering RNAs (siRNAs) and microRNAs (miRNAs)) into cells typically lowers expression of many genes. Unexpectedly, increased expression of genes also occurs. We investigated whether this upregulation results from a saturation effect--that is, competiti...

  19. [Experimental study on human periodontal ligament cells transfected with human amelogenin gene].

    Science.gov (United States)

    Yu, Guang; Shu, Rong; Sun, Ying; Cheng, Lan; Song, Zhong-Chen; Zhang, Xiu-Li

    2008-02-01

    To construct the recombinant lentiviral vector of human amelogenin gene, infect human periodontal ligament cells with the recombinant lentivirus, and evaluate the feasibility of applying modified PDLCs as seeds for a further periodontal reconstruction. The mature peptide of hAm cDNA was cloned and linked into the vector plasmid, the recombinant plasmid FUAmW was confirmed by double enzyme digestion and sequence analysis. Recombinant lentivirus was prepared from 293T cells by polytheylenimine (PEI)-mediated transient cotransfection. The hPDLCs and 293T cells were infected with the generated lentivirus. The infection efficiency was analysed by detection of green fluorescence protein (GFP) with fluorescent microscope and flow cytometer 72 hours later. The expression of hAm gene was detected by reverse transcription polymerase chain reaction (RT-PCR). The sequence of inserted fragment in recombinant plasmid was identical to the hAm sequence reported in Genebank. Green fluorescence was visible under fluorescent microscope, FCM assay showed that positive percentage was 69.46% and 33.99% in 293T and hPDLCs, respectively. The targeted gene was obtained in the experimental groups by RT-PCR. The recombinan lentiviral vector of hAm gene is constructed successfully and it could be transfected into cultured hPDLCs. hAm gene and seed cells may be used for further study in the fields periodontal tissue engineering. Supported by National Natural Science Foundation of China (Grant No. 30672315).

  20. The Synergistic Effect between Electrical and Chemical Factors in Plasma Gene/Molecule-Transfection

    Science.gov (United States)

    Jinno, Masafumi

    2016-09-01

    This study has been done to know what kind of factors in plasma and processes on cells promote plasma gene/molecule transfection. We have discovered a new plasma source using a microcapillary electrode which enables high transfection efficiency and high cell survivability simultaneously. However, the mechanism of the transfection by plasma was not clear. To clarify the transfection mechanisms by micro plasma, we focused on the effects of electrical (current, charge, field, etc.) and chemical (radicals, RONS, etc.) factors generated by the micro plasma and evaluated the contribution weight of three groups of the effects and processes, i.e. electrical, chemical and biochemical ones. At first, the necessity of the electrical factors was estimated by the laser produced plasma (LPP). Mouse L-929 fibroblast cell was cultured on a 96-well plate or 12-well micro slide chamber. Plasmids pCX-EGFP in Tris-EDTA buffer was dropped on the cells and they were exposed to the capillary discharge plasma (CDP) or the LPP. In the case of the CDP, the plasma was generated between the tip of the capillary electrode and the cells so that both electrical and chemical factors were supplied to the cells. In this setup, about 20% of average transfection efficiency was obtained. In the case of the LPP, the plasma was generated apart from the cells so that electrical factors were not supplied to the cells. In this setup, no transfection was observed. These results show that the electrical factors are necessary for the plasma gene transfection. Next, the necessity of the chemical factors was estimated the effect of catalase to remove H2O2 in CDP. The transfection efficiency decreased to 0.4 by scavenging H2O2 with catalase. However, only the solution of H2O2 caused no gene transfection in cells. These results shows that H2O2 is important species to cause gene/molecule transfection but still needs a synergistic effect with electrical or other chemical factors. This work was partly supported by

  1. Photoenhanced gene transfection by a curcumin loaded CS-g-PZLL micelle.

    Science.gov (United States)

    Lin, Jian-Tao; Pan, Wen-Jia; Zhang, Jun-Ai; Wang, Wei; Zhong, Jia; Su, Jia-Min; Li, Tong; Zou, Ying; Wang, Guan-Hai

    2017-09-01

    The codelivery of drug and gene is a promising method for cancer treatment. In our previous works, we prepared a cationic micelles based on chitosan and poly-(N-3-carbobenzyloxylysine) (CS-g-PZLL), but transfection ratio of CS-g-PZLL to Hela cell was low. Herein, to improve the transfection efficiency of CS-g-PZLL, curcumin was loaded in the CS-g-PZLL micelle. After irradiation, the obtained curcumin loaded micelle showed a better transfection, and the p53 protein expression in Hela cells was higher. The apoptosis assay showed that the complex could induce a more significant apoptosis to Hela cells than that of curcumin or p53 used alone, and the curcumin loaded micelle inducing apoptosis was best after irradiation. Therefore, CS-g-PZLL is a safe and effective carrier for the codelivery of drug/gene, and curcumin could be used as a photosensitizer to induce a photoenhanced gene transfection, which should be encouraged in improving transfection and tumor therapy. Copyright © 2017. Published by Elsevier B.V.

  2. Improving ultrasound gene transfection efficiency by controlling ultrasound excitation of microbubbles.

    Science.gov (United States)

    Fan, Z; Chen, D; Deng, C X

    2013-09-28

    Ultrasound application in the presence of microbubbles has shown great potential for non-viral gene transfection via transient disruption of cell membrane (sonoporation). However, improvement of its efficiency has largely relied on empirical approaches without consistent and translatable results. The goal of this study is to develop a rational strategy based on new results obtained using novel experimental techniques and analysis to improve sonoporation gene transfection. In this study, we conducted experiments using targeted microbubbles that were attached to cell membrane to facilitate sonoporation. We quantified the dynamic activities of microbubbles exposed to pulsed ultrasound and the resulting sonoporation outcome, and identified distinct regimes of characteristic microbubble behaviors: stable cavitation, coalescence and translation, and inertial cavitation. We found that inertial cavitation generated the highest rate of membrane poration. By establishing direct correlation of ultrasound-induced bubble activities with intracellular uptake and pore size, we designed a ramped pulse exposure scheme for optimizing microbubble excitation to improve sonoporation gene transfection. We implemented a novel sonoporation gene transfection system using an aqueous two phase system (ATPS) for efficient use of reagents and high throughput operation. Using plasmids coding for the green fluorescence protein (GFP), we achieved a sonoporation transfection efficiency in rate aortic smooth muscle cells (RASMCs) of 6.9%±2.2% (n=9), comparable with lipofection (7.5%±0.8%, n=9). Our results reveal characteristic microbubble behaviors responsible for sonoporation and demonstrated a rational strategy to improve sonoporation gene transfection. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Mannosylated Chitosan Nanoparticles Based Macrophage-Targeting Gene Delivery System Enhanced Cellular Uptake and Improved Transfection Efficiency.

    Science.gov (United States)

    Peng, Yixing; Yao, Wenjun; Wang, Bo; Zong, Li

    2015-04-01

    Gene transfer mediated by mannosylated chitosan (MCS) is a safe and promising approach for gene and vaccine delivery. MCS nanoparticles based gene delivery system showed high in vivo delivery efficiency and elicited strong immune responses in mice. However, little knowledge about the cell binding, transfection efficiency and intracellular trafficking of MCS nanoparticles had been acquired. In this study, using gastrin-releasing peptide as a model plasmid (pGRP), the binding of MCS/pGRP nanoparticles to macrophages and the intracellular trafficking of MCS/pGRP nanoparticles in macrophages were investigated. MCS-mediated transfection efficiency in macrophages was also evaluated using pGL-3 as a reporter gene. The results showed that the binding and transfection efficiency of MCS nanoparticles in macrophages was higher than that of CS, which was attributed to the interaction between mannose ligands in MCS and mannose receptors on the surface of macrophages. Observation with a confocal laser scanning microscope indicated the cellular uptake of MCS/pGRP nanoparticles were more than that of CS/pGRP nanoparticles in macrophages. MCS/pGRP nanoparticles were taken up by macrophages and most of them were entrapped in endosomal/lysosomal compartments. After the nanoparticles escaping from endosomal/lysosomal compartments, naked pGRP entered the nucleus, and a few MCS might enter the nucleus in terms of nanoparticles. Overall, MCS has the potential to be an excellent macrophage-targeting gene delivery carrier.

  4. Gold nanoparticle mediated laser transfection for efficient siRNA mediated gene knock down.

    Directory of Open Access Journals (Sweden)

    Dag Heinemann

    Full Text Available Laser based transfection methods have proven to be an efficient and gentle alternative to established molecule delivery methods like lipofection or electroporation. Among the laser based methods, gold nanoparticle mediated laser transfection bears the major advantage of high throughput and easy usability. This approach uses plasmon resonances on gold nanoparticles unspecifically attached to the cell membrane to evoke transient and spatially defined cell membrane permeabilization. In this study, we explore the parameter regime for gold nanoparticle mediated laser transfection for the delivery of molecules into cell lines and prove its suitability for siRNA mediated gene knock down. The developed setup allows easy usage and safe laser operation in a normal lab environment. We applied a 532 nm Nd:YAG microchip laser emitting 850 ps pulses at a repetition rate of 20.25 kHz. Scanning velocities of the laser spot over the sample of up to 200 mm/s were tested without a decline in perforation efficiency. This velocity leads to a process speed of ∼8 s per well of a 96 well plate. The optimal particle density was determined to be ∼6 particles per cell using environmental scanning electron microscopy. Applying the optimized parameters transfection efficiencies of 88% were achieved in canine pleomorphic adenoma ZMTH3 cells using a fluorescent labeled siRNA while maintaining a high cell viability of >90%. Gene knock down of d2-EGFP was demonstrated and validated by fluorescence repression and western blot analysis. On basis of our findings and established mathematical models we suppose a mixed transfection mechanism consisting of thermal and multiphoton near field effects. Our findings emphasize that gold nanoparticle mediated laser transfection provides an excellent tool for molecular delivery for both, high throughput purposes and the transfection of sensitive cells types.

  5. Gold nanoparticle mediated laser transfection for efficient siRNA mediated gene knock down.

    Science.gov (United States)

    Heinemann, Dag; Schomaker, Markus; Kalies, Stefan; Schieck, Maximilian; Carlson, Regina; Murua Escobar, Hugo; Ripken, Tammo; Meyer, Heiko; Heisterkamp, Alexander

    2013-01-01

    Laser based transfection methods have proven to be an efficient and gentle alternative to established molecule delivery methods like lipofection or electroporation. Among the laser based methods, gold nanoparticle mediated laser transfection bears the major advantage of high throughput and easy usability. This approach uses plasmon resonances on gold nanoparticles unspecifically attached to the cell membrane to evoke transient and spatially defined cell membrane permeabilization. In this study, we explore the parameter regime for gold nanoparticle mediated laser transfection for the delivery of molecules into cell lines and prove its suitability for siRNA mediated gene knock down. The developed setup allows easy usage and safe laser operation in a normal lab environment. We applied a 532 nm Nd:YAG microchip laser emitting 850 ps pulses at a repetition rate of 20.25 kHz. Scanning velocities of the laser spot over the sample of up to 200 mm/s were tested without a decline in perforation efficiency. This velocity leads to a process speed of ∼8 s per well of a 96 well plate. The optimal particle density was determined to be ∼6 particles per cell using environmental scanning electron microscopy. Applying the optimized parameters transfection efficiencies of 88% were achieved in canine pleomorphic adenoma ZMTH3 cells using a fluorescent labeled siRNA while maintaining a high cell viability of >90%. Gene knock down of d2-EGFP was demonstrated and validated by fluorescence repression and western blot analysis. On basis of our findings and established mathematical models we suppose a mixed transfection mechanism consisting of thermal and multiphoton near field effects. Our findings emphasize that gold nanoparticle mediated laser transfection provides an excellent tool for molecular delivery for both, high throughput purposes and the transfection of sensitive cells types.

  6. Gold Nanoparticle Mediated Laser Transfection for Efficient siRNA Mediated Gene Knock Down

    Science.gov (United States)

    Heinemann, Dag; Schomaker, Markus; Kalies, Stefan; Schieck, Maximilian; Carlson, Regina; Escobar, Hugo Murua; Ripken, Tammo; Meyer, Heiko; Heisterkamp, Alexander

    2013-01-01

    Laser based transfection methods have proven to be an efficient and gentle alternative to established molecule delivery methods like lipofection or electroporation. Among the laser based methods, gold nanoparticle mediated laser transfection bears the major advantage of high throughput and easy usability. This approach uses plasmon resonances on gold nanoparticles unspecifically attached to the cell membrane to evoke transient and spatially defined cell membrane permeabilization. In this study, we explore the parameter regime for gold nanoparticle mediated laser transfection for the delivery of molecules into cell lines and prove its suitability for siRNA mediated gene knock down. The developed setup allows easy usage and safe laser operation in a normal lab environment. We applied a 532 nm Nd:YAG microchip laser emitting 850 ps pulses at a repetition rate of 20.25 kHz. Scanning velocities of the laser spot over the sample of up to 200 mm/s were tested without a decline in perforation efficiency. This velocity leads to a process speed of ∼8 s per well of a 96 well plate. The optimal particle density was determined to be ∼6 particles per cell using environmental scanning electron microscopy. Applying the optimized parameters transfection efficiencies of 88% were achieved in canine pleomorphic adenoma ZMTH3 cells using a fluorescent labeled siRNA while maintaining a high cell viability of >90%. Gene knock down of d2-EGFP was demonstrated and validated by fluorescence repression and western blot analysis. On basis of our findings and established mathematical models we suppose a mixed transfection mechanism consisting of thermal and multiphoton near field effects. Our findings emphasize that gold nanoparticle mediated laser transfection provides an excellent tool for molecular delivery for both, high throughput purposes and the transfection of sensitive cells types. PMID:23536802

  7. Optimization of a nonviral transfection system to evaluate Cox-2 controlled interleukin-4 expression for osteoarthritis gene therapy in vitro.

    Science.gov (United States)

    Lang, Annemarie; Neuhaus, Johannes; Pfeiffenberger, Moritz; Schröder, Erik; Ponomarev, Igor; Weber, Yvonne; Gaber, Timo; Schmidt, Michael F G

    2014-01-01

    Gene therapy appears to have the potential for achieving a long-term remedy for osteoarthritis (OA). However, there is a risk of adverse reactions, especially when using cytomegalovirus-controlled expression. To provide a safe application, we focused on the expression of therapeutic cytokines [e.g. interleukin (IL)-4] in a disease-responsive manner by use of the previously cloned Cox-2 promoter as 'genetic switch'. In the present study, we report the functionality of a controlled gene therapeutic system in an equine osteoarthritic cell model. Different nonviral transfection reagents were tested for their efficiency on equine chondrocytes stimulated with equine IL-1β or lipopolysaccharide to create an inflammatory environment. To optimize the transfection, we successfully redesigned the vector by excluding the internal ribosomal entry site (IRES). The functionality of our Cox-2 promoter construct with respect to expressing IL-4 was proven at the mRNA and protein levels and the anti-inflammatory potential of IL-4 was confirmed by analyzing the expression of IL-1β, IL-6, IL-8, matrix metalloproteinase (MMP)-1, MMP-3 and tumor necrosis factor (TNF)-α using a quantitative polymerase chain reaction. Nonviral transfection reagents yielded transfection rates from 21% to 44% with control vectors with and without IRES, respectively. Stimulation of equine chondrocytes resulted in a 20-fold increase of mRNA expression of IL-1β. Such exogenous stimulation of chondrocytes transfected with pNCox2-IL4 led to an increase of IL-4 mRNA expression, whereas expression of inflammatory mediators decreased. The timely link between these events confirms the anti-inflammatory potential of synthesized IL-4. We consider that this approach has significant potential for translation into a useful anti-inflammation therapy. Molecular tools such as the described therapeutic plasmid pave the way for a local-controlled, self-limiting gene therapy. Copyright © 2014 John Wiley & Sons, Ltd.

  8. Rigid aromatic linking moiety in cationic lipids for enhanced gene transfection efficiency.

    Science.gov (United States)

    Wang, Bing; Zhao, Rui-Mo; Zhang, Ji; Liu, Yan-Hong; Huang, Zheng; Yu, Qing-Ying; Yu, Xiao-Qi

    2017-08-18

    Although numerous cationic lipids have been developed as non-viral gene vectors, the structure-activity relationship (SAR) of these materials remains unclear and needs further investigation. In this work, a series of lysine-derived cationic lipids containing linkages with different rigidity were designed and synthesized. SAR studies showed that lipids with rigid aromatic linkage could promote the formation of tight liposomes and enhance DNA condensation, which is essential for the gene delivery process. These lipids could give much higher transfection efficiency than those containing more flexible aliphatic linkage in various cell lines. Moreover, the rigid aromatic linkage also affords the material higher serum tolerance ability. Flow cytometry assay revealed that the target lipids have good cellular uptake, while confocal microscopy observation showed weaker endosome escape than Lipofectamine 2000. To solve such problem and further increase the transfection efficiency, some lysosomotropic reagents were used to improve the endosome escape of lipoplex. As expected, higher transfection efficiency than Lipofectamine 2000 could be obtained via this strategy. Cytotoxicity assay showed that these lipids have lower toxicity in various cell lines than Lipofectamine 2000, suggesting their potential for further application. This work demonstrates that a rigid aromatic linkage might distinctly improve the gene transfection abilities of cationic lipids and affords information to construct safe and efficient gene vector towards practical application. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  9. Pharmaceutical studies for gene therapy: expression of human Cu, Zn-superoxide dismutase gene transfected by lipofection in rat skin fibroblasts.

    Science.gov (United States)

    Nishiguchi, K; Ishida, K; Nakajima, M; Maeda, T; Komada, F; Iwakawa, S; Tanigawara, Y; Okumura, K

    1996-08-01

    To evaluate whether lipofection using Lipofectin is suitable for delivering foreign genes into skin fibroblasts as target cells, we performed experiments using human superoxide dismutase (hSOD) and neomycin-resistance (Neo) genes as models in rat skin fibroblasts (FR and primary cells) in vitro. The amounts of DNA used in the lipofection procedure significantly affected the transfection efficiencies, and the optimal amounts were determined for all cells used. However, the efficiencies in rat skin fibroblasts were about 20-fold higher than that in rat lung epithelial-like cells (L2 cells). The differences in plasmid vectors (pRc/RSV-SOD and pRc/CMV-SOD) hardly affected the transfection efficiencies. The amounts of Lipofectin significantly affected the transfection efficiencies, and the optimal amounts were determined for both types of skin fibroblasts. However, cytotoxic effects in both skin fibroblasts were observed with high doses of Lipofectin. On the other hand, with optimal amounts of DNA and Lipofectin, the reporter gene (NeoT) introduced into cells was mainly integrated into the host cell chromosome. Western blot analysis showed the continuous expression of hSOD protein for at least 45 d in skin fibroblasts transfected with the expression plasmid for hSOD by Lipofectin under the optimal conditions, and the cellular SOD activity fluctuated in parallel with the expression of hSOD protein. Differences in the type of cells also affected the expression of hSOD. These results indicate that it is necessary to set up optimal conditions for transfection using Lipofectin for each cell type, and that transfection with Lipofectin under optimal conditions may be an efficient method for introduction of foreign genes into skin fibroblasts for use as a clinical delivery system of therapeutic protein.

  10. Structure relationship of cationic lipids on gene transfection mediated by cationic liposomes.

    Science.gov (United States)

    Paecharoenchai, Orapan; Niyomtham, Nattisa; Apirakaramwong, Auayporn; Ngawhirunpat, Tanasait; Rojanarata, Theerasak; Yingyongnarongkul, Boon-ek; Opanasopit, Praneet

    2012-12-01

    The aim of this study was to investigate the transfection efficiency of cationic liposomes formulated with phosphatidylcholine (PC) and novel synthesized diethanolamine-based cationic lipids at a molar ratio of 5:1 in comparison with Lipofectamine™ 2000. Factors affecting transfection efficiency and cell viability, including the chemical structure of the cationic lipids, such as different amine head group (diamine and polyamine; and non-spermine and spermine) and acyl chain lengths (C14, C16, and C18) and the weight ratio of liposomes to DNA were evaluated on a human cervical carcinoma cell line (HeLa cells) using the pDNA encoding green fluorescent protein (pEGFP-C2). Characterizations of these lipoplexes in terms of size and charge measurement and agarose gel electrophoresis were performed. The results from this study revealed that almost no transfection was observed in the liposome formulations composed of cationic lipids with a non-spermine head group. In addition, the transfection efficiency of these cationic liposomes was in the following order: spermine-C14 > spermine-C16 > spermine-C18. The highest transfection efficiency was observed in the formulation of spermine-C14 liposomes at a weight ratio of 25; furthermore, this formulation was safe for use in vitro. In conclusion, cationic liposomes containing spermine head groups demonstrated promising potential as gene carriers.

  11. Transfection of the Human Heme Oxygenase Gene Into Rabbit Coronary Microvessel Endothelial Cells: Protective Effect Against Heme and Hemoglobin Toxicity

    Science.gov (United States)

    Abraham, N. G.; Lavrovsky, Y.; Schwartzman, M. L.; Stoltz, R. A.; Levere, R. D.; Gerritsen, M. E.

    1995-07-01

    Heme oxygenase (HO) is a stress protein and has been suggested to participate in defense mechanisms against agents that may induce oxidative injury such as metals, endotoxin, heme/hemoglobin, and various cytokines. Overexpression of HO in cells might therefore protect against oxidative stress produced by certain of these agents, specifically heme and hemoglobin, by catalyzing their degradation to bilirubin, which itself has antioxidant properties. We report here the successful in vitro transfection of rabbit coronary microvessel endothelial cells with a functioning gene encoding the human HO enzyme. A plasmid containing the cytomegalovirus promoter and the human HO cDNA complexed to cationic liposomes (Lipofectin) was used to transfect rabbit endothelial cells. Cells transfected with human HO exhibited an ≈3.0-fold increase in enzyme activity and expressed a severalfold induction of human HO mRNA as compared with endogenous rabbit HO mRNA. Transfected and nontransfected cells expressed factor VIII antigen and exhibited similar acetylated low-density lipoprotein uptake (two important features that characterize endothelial cells) with >85% of cells staining positive for each marker. Moreover, cells transfected with the human HO gene acquired substantial resistance to toxicity produced by exposure to recombinant hemoglobin and heme as compared with nontransfected cells. The protective effect of HO overexpression against heme/hemoglobin toxicity in endothelial cells shown in these studies provides direct evidence that the inductive response of human HO to such injurious stimuli represents an important tissue adaptive mechanism for moderating the severity of cell damage produced by these blood components.

  12. Experimental Model of Gene Transfection in Healthy Canine Myocardium: Perspectives of Gene Therapy for Ischemic Heart Disease

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    Renato A. K. Kalil

    2002-09-01

    Full Text Available OBJECTIVE: To assess the transfection of the gene that encodes green fluorescent protein (GFP through direct intramyocardial injection. METHODS: The pREGFP plasmid vector was used. The EGFP gene was inserted downstream from the constitutive promoter of the Rous sarcoma virus. Five male dogs were used (mean weight 13.5 kg, in which 0.5 mL of saline solution (n=1 or 0.5 mL of plasmid solution containing 0.5 µg of pREGFP/dog (n=4 were injected into the myocardium of the left ventricular lateral wall. The dogs were euthanized 1 week later, and cardiac biopsies were obtained. RESULTS: Fluorescence microscopy showed differences between the cells transfected and not transfected with pREGFP plasmid. Mild fluorescence was observed in the cardiac fibers that received saline solution; however, the myocardial cells transfected with pREGFP had overt EGFP expression. CONCLUSION: Transfection with the EGFP gene in healthy canine myocardium was effective. The reproduction of this efficacy using vascular endothelial growth factor (VEGF instead of EGFP aims at developing gene therapy for ischemic heart disease.

  13. Bacteriophage Mediates Efficient Gene Transfer in Combination with Conventional Transfection Reagents.

    Science.gov (United States)

    Donnelly, Amanda; Yata, Teerapong; Bentayebi, Kaoutar; Suwan, Keittisak; Hajitou, Amin

    2015-12-08

    The development of commercially available transfection reagents for gene transfer applications has revolutionized the field of molecular biology and scientific research. However, the challenge remains in ensuring that they are efficient, safe, reproducible and cost effective. Bacteriophage (phage)-based viral vectors have the potential to be utilized for general gene transfer applications within research and industry. Yet, they require adaptations in order to enable them to efficiently enter cells and overcome mammalian cellular barriers, as they infect bacteria only; furthermore, limited progress has been made at increasing their efficiency. The production of a novel hybrid nanocomplex system consisting of two different nanomaterial systems, phage vectors and conventional transfection reagents, could overcome these limitations. Here we demonstrate that the combination of cationic lipids, cationic polymers or calcium phosphate with M13 bacteriophage-derived vectors, engineered to carry a mammalian transgene cassette, resulted in increased cellular attachment, entry and improved transgene expression in human cells. Moreover, addition of a targeting ligand into the nanocomplex system, through genetic engineering of the phage capsid further increased gene expression and was effective in a stable cell line generation application. Overall, this new hybrid nanocomplex system (i) provides enhanced phage-mediated gene transfer; (ii) is applicable for laboratory transfection processes and (iii) shows promise within industry for large-scale gene transfer applications.

  14. Effects of Microbubble Size on Ultrasound-Mediated Gene Transfection in Auditory Cells

    Directory of Open Access Journals (Sweden)

    Ai-Ho Liao

    2014-01-01

    Full Text Available Gene therapy for sensorineural hearing loss has recently been used to insert genes encoding functional proteins to preserve, protect, or even regenerate hair cells in the inner ear. Our previous study demonstrated a microbubble- (MB-facilitated ultrasound (US technique for delivering therapeutic medication to the inner ear. The present study investigated whether MB-US techniques help to enhance the efficiency of gene transfection by means of cationic liposomes on HEI-OC1 auditory cells and whether MBs of different sizes affect such efficiency. Our results demonstrated that the size of MBs was proportional to the concentration of albumin or dextrose. At a constant US power density, using 0.66, 1.32, and 2.83 μm albumin-shelled MBs increased the transfection rate as compared to the control by 30.6%, 54.1%, and 84.7%, respectively; likewise, using 1.39, 2.12, and 3.47 μm albumin-dextrose-shelled MBs increased the transfection rates by 15.9%, 34.3%, and 82.7%, respectively. The results indicate that MB-US is an effective technique to facilitate gene transfer on auditory cells in vitro. Such size-dependent MB oscillation behavior in the presence of US plays a role in enhancing gene transfer, and by manipulating the concentration of albumin or dextrose, MBs of different sizes can be produced.

  15. Comparative nucleic acid transfection efficacy in primary hepatocytes for gene silencing and functional studies

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    Morral Núria

    2011-01-01

    Full Text Available Abstract Background Primary hepatocytes are the best resource for in vitro studies directed at understanding hepatic processes at the cellular and molecular levels, necessary for novel drug development to treat highly prevalent diseases such as non-alcoholic steatohepatitis, cardiovascular disease and type 2 diabetes. There is a need to identify simple methods to genetically manipulate primary hepatocytes and conduct functional studies with plasmids, small interfering RNA (siRNA or microRNA (miRNA. New lipofection reagents are available that have the potential to yield higher levels of transfection with reduced toxicity. Findings We have tested several liposome-based transfection reagents used in molecular biology research. We show that transfection efficiency with one of the most recently developed formulations, Metafectene Pro, is high with plasmid DNA (>45% cells as well as double stranded RNA (>90% with siRNA or microRNA. In addition, negligible cytotoxicity was present with all of these nucleic acids, even if cells were incubated with the DNA:lipid complex for 16 hours. To provide the proof of concept that these conditions can be used not only for overexpression of a gene of interest, but also in RNA interference applications, we targeted two liver expressed genes, Sterol Regulatory Element-Binding Protein-1 and Fatty Acid Binding Protein 5 using plasmid-mediated short hairpin RNA expression. In addition, similar transfection conditions were used to optimally deliver siRNA and microRNA. Conclusions We have identified a lipid-based reagent for primary hepatocyte transfection of nucleic acids currently used in molecular biology laboratories. The conditions described here can be used to expedite a large variety of research applications, from gene function studies to microRNA target identification.

  16. Stabilizing in vitro ultrasound-mediated gene transfection by regulating cavitation.

    Science.gov (United States)

    Lo, Chia-Wen; Desjouy, Cyril; Chen, Shing-Ru; Lee, Jyun-Lin; Inserra, Claude; Béra, Jean-Christophe; Chen, Wen-Shiang

    2014-03-01

    It is well known that acoustic cavitation can facilitate the inward transport of genetic materials across cell membranes (sonoporation). However, partially due to the unstationary behavior of the initiation and leveling of cavitation, the sonoporation effect is usually unstable, especially in low intensity conditions. A system which is able to regulate the cavitation level during sonication by modulating the applied acoustic intensity with a feedback loop is implemented and its effect on in vitro gene transfection is tested. The regulated system provided better time stability and reproducibility of the cavitation levels than the unregulated conditions. Cultured hepatoma cells (BNL) mixed with 10 μg luciferase plasmids are exposed to 1-MHz pulsed ultrasound with or without cavitation regulation, and the gene transfection efficiency and cell viability are subsequently assessed. Experimental results show that for all exposure intensities (low, medium, and high), stable and intensity dependent, although not higher, gene expression could be achieved in the regulated cavitation system than the unregulated conditions. The cavitation regulation system provides a better control of cavitation and its bioeffect which are crucial important for clinical applications of ultrasound-mediated gene transfection. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Gene Therapy Vectors with Enhanced Transfection Based on Hydrogels Modified with Affinity Peptides

    Science.gov (United States)

    Shepard, Jaclyn A.; Wesson, Paul J.; Wang, Christine E.; Stevans, Alyson C.; Holland, Samantha J.; Shikanov, Ariella; Grzybowski, Bartosz A.; Shea, Lonnie D.

    2011-01-01

    Regenerative strategies for damaged tissue aim to present biochemical cues that recruit and direct progenitor cell migration and differentiation. Hydrogels capable of localized gene delivery are being developed to provide a support for tissue growth, and as a versatile method to induce the expression of inductive proteins; however, the duration, level, and localization of expression isoften insufficient for regeneration. We thus investigated the modification of hydrogels with affinity peptides to enhance vector retention and increase transfection within the matrix. PEG hydrogels were modified with lysine-based repeats (K4, K8), which retained approximately 25% more vector than control peptides. Transfection increased 5- to 15-fold with K8 and K4 respectively, over the RDG control peptide. K8- and K4-modified hydrogels bound similar quantities of vector, yet the vector dissociation rate was reduced for K8, suggesting excessive binding that limited transfection. These hydrogels were subsequently applied to an in vitro co-culture model to induce NGF expression and promote neurite outgrowth. K4-modified hydrogels promoted maximal neurite outgrowth, likely due to retention of both the vector and the NGF. Thus, hydrogels modified with affinity peptides enhanced vector retention and increased gene delivery, and these hydrogels may provide a versatile scaffold for numerous regenerative medicine applications. PMID:21514659

  18. Octaarginine-modified chitosan as a nonviral gene delivery vector: properties and in vitro transfection efficiency

    International Nuclear Information System (INIS)

    Zhao Xiaoli; Li Zhaoyang; Liu Wenguang; Lam, Wingmoon; Sun Peng; Kao, Richard Y. T.; Luk, Keith D. K.; Lu, William W.

    2011-01-01

    Protein transduction domains (PTD) have been identified to have the capacity to facilitate molecular cargo to translocate through cell membrane. This study aims to utilize the cell membrane penetrating ability of octaarginine oligopeptide, a simplified prototype of the PTD, to enhance the transfection efficiency of chitosan. Octaarginine-modified chitosan (R 8 -CS) was synthesized as a gene transfer carrier by carbodiimide chemistry. The structure and composition of R 8 -CSs were characterized using FTIR and 1 H NMR. Agarose gel electrophoresis assay showed that R 8 -CS could efficiently condense the DNA. The particle size of R 8 -CS/DNA complexes were determined to be around 100–200 nm. The nanoparticle complexes exhibited a spherical and compact morphology. R 8 -CS demonstrated higher transfection activity and lower cytotoxicity as compared to the unmodified chitosan and also showed good serum resistance.

  19. Quantitative Evaluation of Myostatin Gene in Stably Transfected Caprine Fibroblast Cells by Anti-Myostatin shRNA.

    Science.gov (United States)

    Jain, Sudhir Kumar; Jain, Hemlata; Kumar, Dharmendra; Bedekar, Megha Kadam; Pandey, Akhilesh Kumar; Sarkhel, Bikash Chandra

    2015-09-01

    Skeletal muscle is the major component of lean tissue that is used for consumption, and myostatin is a negative regulator of skeletal muscle growth. Downregulation of this gene therefore offers a strategy for developing superior animals with enhanced muscle growth. Knockdown of myostatin was achieved by RNA interference technology. The anti-myostatin shRNA were designed and stably transfected in caprine fibroblast cells. The reduced expression of target gene was achieved and measured in clonal fibroblast cells by real-time PCR. Two single-cell clones induced significant decrease of myostatin gene expression by 73.96 and 72.66 %, respectively (P < 0.05). To ensure the appropriate growth of transfected cell, seven media were tested. The best suited media was used for transfected fibroblast cell proliferation. The findings suggest that shRNA provides a novel potential tool for gene knockdown and these stably transfected cells can be used as the donor cells for animal cloning.

  20. One pyrimidine dimer inactivates expression of a transfected gene in xeroderma pigmentosum cells

    International Nuclear Information System (INIS)

    Protic-Sabljic, M.; Kraemer, K.H.

    1985-01-01

    The authors have developed a host cell reactivation assay of DNA repair utilizing UV-treated plasmid vectors. The assay primarily reflects cellular repair of transcriptional activity of damaged DNA measured indirectly as enzyme activity of the transfected genes. They studied three plasmids (pSV2cat, 5020 base pairs; pSV2catSVgpt, 7268 base pairs; and pRSVcat, 5027 base pairs) with different sizes and promoters carrying the bacterial cat gene (CAT, chloramphenicol acetyltransferase) in a construction that permits cat expression in human cells. All human simian virus 40-transformed cells studied expressed high levels of the transfected cat gene. UV treatment of the plasmids prior to transfection resulted in differential decrease in CAT activity in different cell lines. With pSV2catSVgpt, UV inactivation of CAT expression was greater in the xeroderma pigmentosum group A and D lines than in the other human cell lines tested. The D 0 of the CAT inactivation curve was 50 J X m-2 for pSV2cat and for pRSVcat in the xeroderma pigmentosum group A cells. The similarity of the D0 data in the xeroderma pigmentosum group A cells for three plasmids of different size and promoters implies they all have similar UV-inactivation target size. UV-induced pyrimidine dimer formation in the plasmids was quantified by assay of the number of UV-induced T4 endonuclease V-sensitive sites. In the most sensitive xeroderma pigmentosum cells, with all three plasmids, one UV-induced pyrimidine dimer inactivates a target of about 2 kilobases, close to the size of the putative CAT mRNA

  1. Cationic nanoparticles with quaternary ammonium-functionalized PLGA–PEG-based copolymers for potent gene transfection

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yan-Hsung [Kaohsiung Medical University, School of Dentistry, College of Dental Medicine (China); Fu, Yin-Chih [Kaohsiung Medical University, Graduate Institute of Medicine, College of Medicine (China); Chiu, Hui-Chi [Kaohsiung Medical University, Department of Medicinal and Applied Chemistry, College of Life Science (China); Wang, Chau-Zen [Kaohsiung Medical University, Department of Physiology, College of Medicine (China); Lo, Shao-Ping [Kaohsiung Medical University, Department of Medicinal and Applied Chemistry, College of Life Science (China); Ho, Mei-Ling [Kaohsiung Medical University, Department of Physiology, College of Medicine (China); Liu, Po-Len [Kaohsiung Medical University, Department of Respiratory Therapy, College of Medicine (China); Wang, Chih-Kuang, E-mail: ckwang@kmu.edu.tw [Kaohsiung Medical University, Department of Medicinal and Applied Chemistry, College of Life Science (China)

    2013-11-15

    The objective of the present work was to develop new cationic nanoparticles (cNPs) with amphiphilic cationic copolymers for the delivery of plasmid DNA (pDNA). Cationic copolymers were built on the synthesis of quaternary ammonium salt compounds from diethylenetriamine (DETA) to include the positively charged head group and amphiphilic multi-grafts. PLGA-phe-PEG-qDETA (PPD), phe-PEG-qDETA-PLGA (PDP), and PLGA-phe-PEG-qDETA-PLGA (PPDP) cationic copolymers were created by this moiety of DETA quaternary ammonium, heterobifunctional polyethylene glycol (COOH-PEG-NH{sub 2}), phenylalanine (phe), and poly(lactic-co-glycolic acid) (PLGA). These new cNPs were prepared by the water miscible solvent displacement method. They exhibit good pDNA binding ability, as shown in a retardation assay that occurred at a particle size of ∼217 nm. The zeta potential was approximately +21 mV when the cNP concentration was 25 mg/ml. The new cNPs also have a better buffering capacity than PLGA NPs. However, the pDNA binding ability was demonstrated starting at a weight ratio of approximately 6.25 cNPs/pDNA. Gene transfection results showed that these cNPs had transfection effects similar to those of Lipofectamine 2000 in 293T cells. Furthermore, cNPs can also transfect human adipose-derived stem cells. The results indicate that the newly developed cNP is a promising candidate for a novel gene delivery vehicle.

  2. Cytokinesis is blocked in mammalian cells transfected with Chlamydia trachomatis gene CT223

    Directory of Open Access Journals (Sweden)

    Weeks Sara K

    2009-01-01

    Full Text Available Abstract Background The chlamydiae alter many aspects of host cell biology, including the division process, but the molecular biology of these alterations remains poorly characterized. Chlamydial inclusion membrane proteins (Incs are likely candidates for direct interactions with host cell cytosolic proteins, as they are secreted to the inclusion membrane and exposed to the cytosol. The inc gene CT223 is one of a sequential set of orfs that encode or are predicted to encode Inc proteins. CT223p is localized to the inclusion membrane in all tested C. trachomatis serovars. Results A plasmid transfection approach was used to examine the function of the product of CT223 and other Inc proteins within uninfected mammalian cells. Fluorescence microscopy was used to demonstrate that CT223, and, to a lesser extent, adjacent inc genes, are capable of blocking host cell cytokinesis and facilitating centromere supranumeracy defects seen by others in chlamydiae-infected cells. Both phenotypes were associated with transfection of plasmids encoding the carboxy-terminal tail of CT223p, a region of the protein that is likely exposed to the cytosol in infected cells. Conclusion These studies suggest that certain Inc proteins block cytokinesis in C. trachomatis-infected cells. These results are consistent with the work of others showing chlamydial inhibition of host cell cytokinesis.

  3. Intracellular Protein Delivery and Gene Transfection by Electroporation Using a Microneedle Electrode Array

    Science.gov (United States)

    Choi, Seong-O; Kim, Yeu-Chun; Lee, Jeong Woo; Park, Jung-Hwan

    2012-01-01

    The impact of many biopharmaceuticals, including protein- and gene-based therapies, has been limited by the need for better methods of delivery into cells within tissues. Here, we present intracellular delivery of molecules and transfection with plasmid DNA by electroporation using a novel microneedle electrode array designed for targeted treatment of skin and other tissue surfaces. The microneedle array is molded out of polylactic acid. Electrodes and circuitry required for electroporation are applied to the microneedle array surface by a new metal-transfer micromolding method. The microneedle array maintains mechanical integrity after insertion into pig cadaver skin and is able to electroporate human prostate cancer cells in vitro. Quantitative measurements show that increasing electroporation pulse voltage increases uptake efficiency of calcein and bovine serum albumin, whereas increasing pulse length has lesser effects over the range studied. Uptake of molecules by up to 50 % of cells and transfection of 12 % of cells with a gene for green fluorescent protein is demonstrated at high cell viability. We conclude that the microneedle electrode array is able to electroporate cells, resulting in intracellular uptake of molecules, and has potential applications to improve intracellular delivery of proteins, DNA and other biopharmaceuticals. PMID:22328093

  4. Transfection of the IHH gene into rabbit BMSCs in a simulated microgravity environment promotes chondrogenic differentiation and inhibits cartilage aging.

    Science.gov (United States)

    Liu, Peng-Cheng; Liu, Kuan; Liu, Jun-Feng; Xia, Kuo; Chen, Li-Yang; Wu, Xing

    2016-09-27

    The effect of overexpressing the Indian hedgehog (IHH) gene on the chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMSCs) was investigated in a simulated microgravity environment. An adenovirus plasmid encoding the rabbit IHH gene was constructed in vitro and transfected into rabbit BMSCs. Two large groups were used: conventional cell culture and induction model group and simulated microgravity environment group. Each large group was further divided into blank control group, GFP transfection group, and IHH transfection group. During differentiation induction, the expression levels of cartilage-related and cartilage hypertrophy-related genes and proteins in each group were determined. In the conventional model, the IHH transfection group expressed high levels of cartilage-related factors (Coll2 and ANCN) at the early stage of differentiation induction and expressed high levels of cartilage hypertrophy-related factors (Coll10, annexin 5, and ALP) at the late stage. Under the simulated microgravity environment, the IHH transfection group expressed high levels of cartilage-related factors and low levels of cartilage hypertrophy-related factors at all stages of differentiation induction. Under the simulated microgravity environment, transfection of the IHH gene into BMSCs effectively promoted the generation of cartilage and inhibited cartilage aging and osteogenesis. Therefore, this technique is suitable for cartilage tissue engineering.

  5. Enhancement of ultraviolet-DNA repair in denV gene transfectants and T4 endonuclease V-liposome recipients

    International Nuclear Information System (INIS)

    Kibitel, J.T.; Yee, V.; Yarosh, D.B.

    1991-01-01

    The phage T4 denV gene, coding for the pyrimidine-dimer specific T4 endonuclease V, was transfected into human repair-proficient fibroblasts, repair-deficient xeroderma pigmentosum fibroblasts, and wild type CHO hamster cells. Transfectants maintained denV DNA and expressed denV mRNA. Purified T4 endonuclease V encapsulated in liposomes was also used to treat repair-proficient and -deficient human cells. The denV transfected clones and liposome-treated cells showed increased unscheduled DNA synthesis and enhanced removal of pyrimidine dimers compared to controls. Both denV gene transfection and endonuclease V liposome treatment enhanced post-UV survival in xeroderma pigmentosum cells but had no effect on survival in repair-proficient human or hamster cells. The results demonstrate that an exogenous DNA repair enzyme can correct the DNA repair defect in xeroderma pigmentosum cells and enhance DNA repair in normal cells. (author)

  6. Differential transfection efficiency rates of the GM-CSF gene into human renal cell carcinoma lines by lipofection.

    Science.gov (United States)

    Hernández, A; Zöller, K; Enczmann, J; Ebert, T; Schmitz-Draeger, B; Ackermann, R; Wernet, P

    1997-01-01

    One of the major questions in any gene therapy approach is the selection of the appropriate vector system. Here, the optimization of a gene transfer protocol for renal cell carcinoma using lipofection as a nonviral gene transduction system was evaluated. To select the promoter which gives the highest expression, different plasmids which are able to express Escherichia coli beta-galactosidase gene as a reporter gene under the control of different promoters were tested: human cytomegalovirus promoter (pCMVbeta), simian virus 40 promoter (pSVbeta), adenovirus promoter (ADbeta), and herpes simplex virus thymidine kinase promoter (TKbeta). The pCMVbeta revealed the highest expression of the beta-gal gene in the renal cell carcinoma (RCC) lines. Thus this CMV promoter was selected for the expression of the granulocyte-macrophage colony stimulator factor (GM-CSF) gene. Three different lipids (LipofectAmine, LipofectAce, and Lipofectin) were compared for their transduction efficiency, and the optimal conditions for quantitatively high lipofection rates were established. The consistently best results regarding gene expression as well as viability of the RCC lines were obtained when Lipofectin was used. Gene expression was monitored by a specific enzyme-linked immunosorbent assay and functionally validated by a cell proliferation test. The GM-CSF expression profile showed a peak at 48 hours after transfection and was still detectable after 5 days. Here the feasibility of efficient lipofection of the GM-CSF gene into RCC lines is demonstrated. Most importantly, considerable differences in the relative quantity of GM-CSF gene transfer into the different RCC lines was observed here. This may be of critical relevance for the design of any clinical gene transduction protocol in tumor cell vaccination attempts.

  7. Inhibition of human colorectal adenocarcinoma cells with AdCMV-p53 gene transfection induced by irradiation

    International Nuclear Information System (INIS)

    Liu Bing; Min Fengling; Xie Yi; Zhou Qingming; Duan Xin; Chinese Academy of Sciences, Beijing; Zhang Hong; Li Wenjian; Hao Jifang; Zhou Guangming; Gao Qingxiang

    2006-01-01

    The effect of AdCMV-p53 gene transfection induced by γ-ray irradiation on human colorectal adenocarcinoma cells was investigated. The HT-29 cells were irradiated by 0.5, 1.0, 2.0 Gy 60 Co γ-rays, then were transfected with AdCMV-GFP (a replication of deficient recombinant adenoviral vector containing a CMV promoter and green fluorescent protein) or AdCMV-p53 (a replication of deficient recombinant adenoviral vector containing a CMV promoter and carrying human wild p53 gene). Cytotoxity was measured by clonogenic survival assay; apoptosis and the p53 expression were determined by flow cytometry. The results show that the pre-exposure of 0.5 Gy 60 Co γ-rays significantly enhanced the inhibition of HT-29 cells with AdCMV-53 transfection and promoted cell apoptosis. The inhibition rates for the groups of pre-exposure with 0.5 Gy and transfection with 40 and 80 MOI AdCMV-p53 were 50% and 20% higher than those for the groups of the mere transfection, and 40% more than the mere irradiation group. In the case of higher than 0.5 Gy pre-exposure, no significant difference was found between the pre-exposure with transfection group and the mere irradiation group. So 0.5 Gy pre-irradiation and AdCMV-p53 transfection obviously increases the inhibition of HT-29 cells with AdCMV-p53 transfection. The optimum condition is the lower than 1.0 Gy pre-exposure combined with the lower than 80 MOI AdCMV-p53 transfection. (authors)

  8. Transfection of wild type ADVP53 gene into human brain tumor cell lines has a radiosensitizing effect independent of apoptosis

    International Nuclear Information System (INIS)

    Geng, L.; Walter, S; Vaughan, A.T.M.

    1997-01-01

    Purpose: Despite attempts with a variety of therapeutic approaches there has been little impact on the survival of patients with Glioblastoma multiforme, with median survivals reported of approximately 12 months. In this study a replication restricted adenovirus vector is used to transfer the wild type p53 gene into two cell lines derived from a human astrocytoma U87MG or glioblastoma T98G, to determine its ability to act as a radiosensitizer in conjunction with conventional radiotherapy. Methods: An adenovirus vector containing the human wild type p53 (Advp53) gene was used in addition to a control vector containing the β-galactosidase (Advγgal) reporter gene. To achieve cellular incorporation both vectors were incubated with cells for 30 minutes - washed and returned to culture. The successful incorporation of each vector was determined by either a p53 assay using either a western blotting or flow cytometry techniques, or specific staining for β-galactosidase activity. The presence of each vector was assayed until the constructs were eliminated from the cell. To determine the effects of these vectors on cell survival sufficient vector was added to produce a measurable reduction in clonogenic survival and this value was used in subsequent irradiation experiments. To determine the ability of wild type p53 to induce apoptosis the cells were examined from 1 to 5 days after irradiation by H and E staining for the characteristic morphology indicating an apoptotic process. Results: Both the Advp53 and Advβgal vectors were successfully incorporated into each cell line. Expression of each gene was reduced to approximately half by 5 days and virtually eliminated by 15 days after transfection in both lines. At the doses used the wild type Advp53 adenovirus was toxic to both cell lines giving surviving fractions between 39-74%. When this toxicity was taken into account the presence of the Advp53 gene had a radiosensitizing effect in each cell line. To determine the

  9. Size effect on transfection and cytotoxicity of nanoscale plasmid DNA/polyethyleneimine complexes for aerosol gene delivery

    Energy Technology Data Exchange (ETDEWEB)

    Hoon Byeon, Jeong, E-mail: jbyeon@purdue.edu [Department of Chemistry, Purdue University, West Lafayette, Indiana 47907 (United States); Kim, Jang-Woo, E-mail: jwkim@hoseo.edu [Department of Digital Display Engineering, Hoseo University, Asan 336-795 (Korea, Republic of)

    2014-02-03

    Nanoscale plasmid DNA (pDNA)/polyethyleneimine (PEI) complexes were fabricated in the aerosol state using a nebulization system consisting of a collison atomizer and a cool-walled diffusion dryer. The aerosol fabricated nanoscale complexes were collected and employed to determine fundamental properties of the complexes, such as size, structure, surface charge, and in vitro gene transfection efficiency and cytotoxicity. The results showed that mass ratio between pDNA and PEI should be optimized to enhance gene transfection efficiency without a significant loss of cell viability. These findings may support practical advancements in the field of nonviral gene delivery.

  10. A convenient method of preparing gene vector for real time monitoring transfection process based on the quantum dots

    International Nuclear Information System (INIS)

    Zhang, Hai-Li; Zhang, Ming-Zhen; Li, Xiang-Yong; Wan, Min; Li, Yong-Qiang; Zhang, Rong-Ying; Zhao, Yuan-Di

    2012-01-01

    Highlights: ► An easy and direct way to prepare QDs–DNA complexes was developed. ► Surface charge of QDs was tuned with different ratio of amino and glycolate. ► Transfection efficiency was dependent on the surface zeta potentials of QDs. ► Cellular toxicity of this gene vectors is much lower than commercial liposome. ► Whole intracellular behavior of QDs–DNA complexes can be monitored in real time. -- Abstract: Nanoparticle carrier has been developed by combining water-soluble quantum dots and plasmid DNA expressed enhanced green fluorescent protein (EGFP) in a convenient and direct way. First the QDs with different surface charges were obtained by coating with amino and carboxyl terminals at different ratios. Then plasmid DNA was conjugated to QDs via electrostatic interaction. The resultant QDs–DNA complexes showed enhanced resistance to DNase I digestion. The following transfection experiments demonstrated that the transfection efficiency was dependent on the surface charges on QDs. The real time imaging of the transfection process showed that the nanoparticles experienced binding, penetrating the cell membrane and entering cytoplasm in the first 6 h of transfection. The green fluorescence of EGFP began to appear after 18 h transfection and plasmid DNA was fully expressed in the following 6 h. This new QDs–DNA platform showed great potential as new gene delivery carrier.

  11. A convenient method of preparing gene vector for real time monitoring transfection process based on the quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hai-Li; Zhang, Ming-Zhen; Li, Xiang-Yong [Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China); Key Laboratory of Biomedical Photonics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China); Wan, Min [Key Laboratory of Biomedical Photonics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China); Li, Yong-Qiang [Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China); Key Laboratory of Biomedical Photonics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China); Zhang, Rong-Ying [Key Laboratory of Biomedical Photonics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China); Zhao, Yuan-Di, E-mail: zydi@mail.hust.edu.cn [Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China); Key Laboratory of Biomedical Photonics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan 430074 (China)

    2012-11-15

    Highlights: ► An easy and direct way to prepare QDs–DNA complexes was developed. ► Surface charge of QDs was tuned with different ratio of amino and glycolate. ► Transfection efficiency was dependent on the surface zeta potentials of QDs. ► Cellular toxicity of this gene vectors is much lower than commercial liposome. ► Whole intracellular behavior of QDs–DNA complexes can be monitored in real time. -- Abstract: Nanoparticle carrier has been developed by combining water-soluble quantum dots and plasmid DNA expressed enhanced green fluorescent protein (EGFP) in a convenient and direct way. First the QDs with different surface charges were obtained by coating with amino and carboxyl terminals at different ratios. Then plasmid DNA was conjugated to QDs via electrostatic interaction. The resultant QDs–DNA complexes showed enhanced resistance to DNase I digestion. The following transfection experiments demonstrated that the transfection efficiency was dependent on the surface charges on QDs. The real time imaging of the transfection process showed that the nanoparticles experienced binding, penetrating the cell membrane and entering cytoplasm in the first 6 h of transfection. The green fluorescence of EGFP began to appear after 18 h transfection and plasmid DNA was fully expressed in the following 6 h. This new QDs–DNA platform showed great potential as new gene delivery carrier.

  12. A method to detect transfected chloramphenicol acetyltransferase gene expression in intact animals

    International Nuclear Information System (INIS)

    Narayanan, R.; Jastreboff, M.M.; Chiu, Chang Fang; Ito, Etsuro; Bertino, J.R.

    1988-01-01

    A rapid procedure is described for assaying chloramphenicol acetyltransferase enzyme activity in intact animals following transfection of the RSV CAT plasmid into mouse bone marrow cells by electroporation. The reconstituted mice were injected with [ 14 C]chloramphenicol and ethyl acetate extracts of 24-h urine samples were analyzed by TLC autoradiography for the excretion of 14 C-labeled metabolites. CAT expression in vivo can be detected by the presence of acetylated 14 C-labeled metabolites in the urine within 1 week after bone marrow transplantation and, under the conditions described, these metabolites can be detected for at least 3 months. CAT expression in intact mice as monitored by the urine assay correlates with the CAT expression in the hematopoietic tissues assayed in vitro. This method offers a quick mode of screening for introduced CAT gene expression in vivo without sacrificing the mice

  13. Gene-carried hepatoma targeting complex induced high gene transfection efficiency with low toxicity and significant antitumor activity

    Directory of Open Access Journals (Sweden)

    Zhao QQ

    2012-06-01

    Full Text Available Qing-Qing Zhao,1,2 Yu-Lan Hu,1 Yang Zhou,3 Ni Li,1 Min Han,1 Gu-Ping Tang,4 Feng Qiu,2 Yasuhiko Tabata,5 Jian-Qing Gao,11Institute of Pharmaceutics, Zhejiang University, Hangzhou, China; 2Department of Pharmacy, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China; 3Institute of Biochemistry, Iowa State University, Ames, IA, USA; 4Institute of Chemical Biology and Pharmaceutical Chemistry, Zhejiang University, Hangzhou, China; 5Institute for Frontier Medical Sciences, Kyoto University, Kyoto, JapanBackground: The success of gene transfection is largely dependent on the development of a vehicle or vector that can efficiently deliver a gene to cells with minimal toxicity.Methods: A liver cancer-targeted specific peptide (FQHPSF sequence was successfully synthesized and linked with chitosan-linked polyethylenimine (CP to form a new targeted gene delivery vector called CPT (CP/peptide. The structure of CPT was confirmed by 1H nuclear magnetic resonance spectroscopy and ultraviolet spectrophotometry. The particle size of CPT/DNA complexes was measured using laser diffraction spectrometry and the cytotoxicity of the copolymer was evaluated by methylthiazol tetrazolium method. The transfection efficiency evaluation of the CP copolymer was performed using luciferase activity assay. Cellular internalization of the CP/DNA complex was observed under confocal laser scanning microscopy. The targeting specificity of the polymer coupled to peptide was measured by competitive inhibition transfection study. The liver targeting specificity of the CPT copolymer in vivo was demonstrated by combining the copolymer with a therapeutic gene, interleukin-12, and assessed by its abilities in suppressing the growth of ascites tumor in mouse model.Results: The results showed that the liver cancer-targeted specific peptide was successfully synthesized and linked with CP to form a new targeted gene delivery vector called CPT. The composition of CPT

  14. Acceleration of gene transfection efficiency in neuroblastoma cells through polyethyleneimine/poly(methyl methacrylate core-shell magnetic nanoparticles

    Directory of Open Access Journals (Sweden)

    Tencomnao T

    2012-06-01

    Full Text Available Tewin Tencomnao,1,* Kewalin Klangthong,2,* Nuttaporn Pimpha,3 Saowaluk Chaleawlert-umpon,3 Somsak Saesoo,3 Noppawan Woramongkolchai,3 Nattika Saengkrit,31Center for Excellence in Omics-Nano Medical Technology Development Project, 2Graduate Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, 3National Nanotechnology Center, National Science and Technology Development Agency, Pathumthani, Thailand*Both authors contributed equally to this workBackground: The purpose of this study was to demonstrate the potential of magnetic poly(methyl methacrylate (PMMA core/polyethyleneimine (PEI shell (mag-PEI nanoparticles, which possess high saturation magnetization for gene delivery. By using mag-PEI nanoparticles as a gene carrier, this study focused on evaluation of transfection efficiency under magnetic induction. The potential role of this newly synthesized nanosphere for therapeutic delivery of the tryptophan hydroxylase-2 (TPH-2 gene was also investigated in cultured neuronal LAN-5 cells.Methods: The mag-PEI nanoparticles were prepared by one-step emulsifier-free emulsion polymerization, generating highly loaded and monodispersed magnetic polymeric nanoparticles bearing an amine group. The physicochemical properties of the mag-PEI nanoparticles and DNA-bound mag-PEI nanoparticles were investigated using the gel retardation assay, atomic force microscopy, and zeta size measurements. The gene transfection efficiencies of mag-PEI nanoparticles were evaluated at different transfection times. Confocal laser scanning microscopy confirmed intracellular uptake of the magnetoplex. The optimal conditions for transfection of TPH-2 were selected for therapeutic gene transfection. We isolated the TPH-2 gene from the total RNA of the human medulla oblongata and cloned it into an expression vector. The plasmid containing TPH-2 was subsequently bound onto the

  15. Mesoporous Silica Nanomaterials for Applications in Catalysis, Sensing, Drug Delivery and Gene Transfection

    Energy Technology Data Exchange (ETDEWEB)

    Radu, Daniela Rodica [Iowa State Univ., Ames, IA (United States)

    2004-01-01

    the surface of MSN and utilize them to complex cationic DNA. The p-EGFP-CI gene-coated MSN nanocomposite was able to transfect cancer cell lines, such as human HeLa and CHO cancer cell lines. The gene carrier ability of MSNs was further proved by transfecting primary cells and cotransfecting of two different genes in cancer cell lines. In sum, MSN are versatile partners in several types of applications.

  16. Thermal response of rat fibroblasts stably transfected with the human 70-kDa heat shock protein-encoding gene

    International Nuclear Information System (INIS)

    Li, G.C.; Li, Ligeng; Liu, Yunkang; Mak, J.Y.; Chen, Lili; Lee, W.M.F.

    1991-01-01

    The major heat shock protein hsp70 is synthesized by cells of a wide variety of organisms in response to heat shock or other environmental stresses and is assumed to play an important role in protecting cells from thermal stress. The authors have tested this hypothesis directly by transfecting a constitutively expressed recombinant human hsp70-encoding gene into rat fibroblasts and examining the relationship between the levels of human hsp70 expressed and thermal resistance of the stably transfected rat cells. Successful transfection and expression of the gene for human hsp70 were characterized by RNA hybridization analysis, low-dimensional gel electrophoresis, and immunoblot analysis. When individual cloned cell lines were exposed to 45C and their thermal survivals were determined by colony-formation assay, they found that the expression of human hsp70 conferred heat resistance to the rat cells. These results reinforce the hypothesis that hsp70 has a protective function against thermal stress

  17. Over-expression of brain-derived neurotrophic factor in mesenchymal stem cells transfected with recombinant lentivirus BDNF gene.

    Science.gov (United States)

    Zhang, X; Zhu, J; Zhang, K; Liu, T; Zhang, Z

    2016-12-30

    This study was aimed at investigating the expression of brain-derived neurotrophic factor (BDNF) in mesenchymal stem cells (MSCs) modified with recombinant lentivirus bearing BDNF gene. Lentivirus vectors bearing BDNF gene were constructed. MSCs were isolated from rats and cultured. The lentiviral vectors containing BDNF gene were transfected into the MSCs, and BDNF gene and protein expressions were monitored with enhanced green fluorescent protein (EGFP). RT-PCR and Western blot were used to measure gene and protein expressions, respectibvely in MSCs, MSCs-EGFP and MSCs-EGFP-BDNF groups. Green fluorescence assay confirmed successful transfection of BDNF gene recombinant lentivirus into MSCs. RT-PCR and Western blot revealed that BDNF gene and protein expressions in the MSCs-EGFP-BDNF group were significantly higher than that in MSCs group and MSCs-EGFP group. There were no statistically significant differences in gene expression between MSCs and MSCs-EGFP groups. MSCs can over-express BDNF when transfected with recombinant lentivirus bearing BDNF gene.

  18. Genetically engineered cardiac pacemaker: Stem cells transfected with HCN2 gene and myocytes-A model

    Energy Technology Data Exchange (ETDEWEB)

    Kanani, S. [Institut Genomique Fonctionelle, 141 Rue de la Cardonille, 34396 Montpellier (France); Institut Non Lineaire de Nice, CNRS and Universite de Nice, 1361 route des Lucioles, 06560 Valbonne (France); Pumir, A. [Institut Non Lineaire de Nice, CNRS and Universite de Nice, 1361 route des Lucioles, 06560 Valbonne (France); Laboratoire J.A. Dieudonne, CNRS and Universite de Nice, Parc Valrose, 06108 Nice (France)], E-mail: alain.pumir@unice.fr; Krinsky, V. [Institut Non Lineaire de Nice, CNRS and Universite de Nice, 1361 route des Lucioles, 06560 Valbonne (France)

    2008-01-07

    One of the successfully tested methods to design genetically engineered cardiac pacemaker cells consists in transfecting a human mesenchymal stem cell (hMSC) with a HCN2 gene and connecting it to a myocyte. We develop and study a mathematical model, describing a myocyte connected to a hMSC transfected with a HCN2 gene. The cardiac action potential is described both with the simple Beeler-Reuter model, as well as with the elaborate dynamic Luo-Rudy model. The HCN2 channel is described by fitting electrophysiological records, in the spirit of Hodgkin-Huxley. The model shows that oscillations can occur in a pair myocyte-stem cell, that was not observed in the experiments yet. The model predicted that: (1) HCN pacemaker channels can induce oscillations only if the number of expressed I{sub K1} channels is low enough. At too high an expression level of I{sub K1} channels, oscillations cannot be induced, no matter how many pacemaker channels are expressed. (2) At low expression levels of I{sub K1} channels, a large domain of values in the parameter space (n, N) exists, where oscillations should be observed. We denote N the number of expressed pacemaker channels in the stem cell, and n the number of gap junction channels coupling the stem cell and the myocyte. (3) The expression levels of I{sub K1} channels observed in ventricular myocytes, both in the Beeler-Reuter and in the dynamic Luo-Rudy models are too high to allow to observe oscillations. With expression levels below {approx}1/4 of the original value, oscillations can be observed. The main consequence of this work is that in order to obtain oscillations in an experiment with a myocyte-stem cell pair, increasing the values of n, N is unlikely to be helpful, unless the expression level of I{sub K1} has been reduced enough. The model also allows us to explore levels of gene expression not yet achieved in experiments, and could be useful to plan new experiments, aimed at improving the robustness of the oscillations.

  19. Genetically engineered cardiac pacemaker: Stem cells transfected with HCN2 gene and myocytes—A model

    Science.gov (United States)

    Kanani, S.; Pumir, A.; Krinsky, V.

    2008-01-01

    One of the successfully tested methods to design genetically engineered cardiac pacemaker cells consists in transfecting a human mesenchymal stem cell (hMSC) with a HCN2 gene and connecting it to a myocyte. We develop and study a mathematical model, describing a myocyte connected to a hMSC transfected with a HCN2 gene. The cardiac action potential is described both with the simple Beeler Reuter model, as well as with the elaborate dynamic Luo Rudy model. The HCN2 channel is described by fitting electrophysiological records, in the spirit of Hodgkin Huxley. The model shows that oscillations can occur in a pair myocyte-stem cell, that was not observed in the experiments yet. The model predicted that: (1) HCN pacemaker channels can induce oscillations only if the number of expressed I channels is low enough. At too high an expression level of I channels, oscillations cannot be induced, no matter how many pacemaker channels are expressed. (2) At low expression levels of I channels, a large domain of values in the parameter space (n, N) exists, where oscillations should be observed. We denote N the number of expressed pacemaker channels in the stem cell, and n the number of gap junction channels coupling the stem cell and the myocyte. (3) The expression levels of I channels observed in ventricular myocytes, both in the Beeler Reuter and in the dynamic Luo Rudy models are too high to allow to observe oscillations. With expression levels below ˜1/4 of the original value, oscillations can be observed. The main consequence of this work is that in order to obtain oscillations in an experiment with a myocyte-stem cell pair, increasing the values of n, N is unlikely to be helpful, unless the expression level of I has been reduced enough. The model also allows us to explore levels of gene expression not yet achieved in experiments, and could be useful to plan new experiments, aimed at improving the robustness of the oscillations.

  20. Targeted transfection increases siRNA uptake and gene silencing of primary endothelial cells in vitro--a quantitative study.

    Science.gov (United States)

    Asgeirsdóttir, Sigridur A; Talman, Eduard G; de Graaf, Inge A; Kamps, Jan A A M; Satchell, Simon C; Mathieson, Peter W; Ruiters, Marcel H J; Molema, Grietje

    2010-01-25

    Applications of small-interfering RNA (siRNA) call for specific and efficient delivery of siRNA into particular cell types. We developed a novel, non-viral targeting system to deliver siRNA specifically into inflammation-activated endothelial cells. This was achieved by conjugating the cationic amphiphilic lipid SAINT to antibodies recognizing the inflammatory cell adhesion molecule E-selectin. These anti-E-selectin-SAINT lipoplexes (SAINTarg) maintained antigen recognition capacity of the parental antibody in vitro, and ex vivo in human kidney tissue slices subjected to inflammatory conditions. Regular SAINT mediated transfection resulted in efficient gene silencing in human microvascular endothelial cells (HMEC-1) and conditionally immortalized glomerular endothelial cells (ciGEnC). However, primary human umbilical vein endothelial cells (HUVEC) transfected poorly, a phenomenon that we could quantitatively correlate with a cell-type specific capacity to facilitate siRNA uptake. Importantly, SAINTarg increased siRNA uptake and transfection specificity for activated endothelial cells. Transfection with SAINTarg delivered significantly more siRNA into activated HUVEC, compared to transfection with non-targeted SAINT. The enhanced uptake of siRNA was corroborated by improved silencing of both gene- and protein expression of VE-cadherin in activated HUVEC, indicating that SAINTarg delivered functionally active siRNA into endothelial cells. The obtained results demonstrate a successful design of a small nucleotide carrier system with improved and specific siRNA delivery into otherwise difficult-to-transfect primary endothelial cells, which in addition reduced considerably the amount of siRNA needed for gene silencing. Copyright 2009 Elsevier B.V. All rights reserved.

  1. Targeted retrograde transfection of adenovirus vector carrying brain-derived neurotrophic factor gene prevents loss of mouse (twy/twy) anterior horn neurons in vivo sustaining mechanical compression.

    Science.gov (United States)

    Xu, Kan; Uchida, Kenzo; Nakajima, Hideaki; Kobayashi, Shigeru; Baba, Hisatoshi

    2006-08-01

    Immunohistochemical analysis after adenovirus (AdV)-mediated BDNF gene transfer in and around the area of mechanical compression in the cervical spinal cord of the hyperostotic mouse (twy/twy). To investigate the neuroprotective effect of targeted AdV-BDNF gene transfection in the twy mouse with spontaneous chronic compression of the spinal cord motoneurons. Several studies reported the neuroprotective effects of neurotrophins on injured spinal cord. However, no report has described the effect of targeted retrograde neurotrophic gene delivery on motoneuron survival in chronic compression lesions of the cervical spinal cord resembling lesions of myelopathy. LacZ marker gene using adenoviral vector (AdV-LacZ) was used to evaluate retrograde delivery from the sternomastoid muscle in adult twy mice (16-week-old) and (control). Four weeks after the AdV-LacZ or AdV-BDNF injection, the compressed cervical spinal cord was removed en bloc for immunohistologic investigation of b-galactosidase activity and immunoreactivity and immunoblot analyses of BDNF. The number of anterior horn neurons was counted using Nissl, ChAT and AChE staining. Spinal accessory motoneurons between C1 and C3 segments were successfully transfected by AdV-LacZ in both twy and ICR mice after targeted intramuscular injection. Immunoreactivity to BDNF was significantly stronger in AdV-BDNF-gene transfected twy mice than in AdV-LacZ-gene transfected mice. At the cord level showing the maximum compression in AdV-BDNF-transfected twy mice, the number of anterior horn neurons was sinificantly higher in the topographic neuronal cell counting of Nissl-, ChAT-, and AChE-stained samples than in AdV-LacZ-injected twy mice. Targeted AdV-BDNF-gene delivery significantly increased Nissl-stained anterior horn neurons and enhanced cholinergic enzyme activities in the twy. Our results suggest that targeted retrograde AdV-BDNF-gene in vivo delivery may enhance neuronal survival even under chronic mechanical compression.

  2. Novel N,N '-diacyl-1,3-diaminopropyl-2-carbamoyl bivalent cationic lipids for gene delivery--synthesis, in vitro transfection activity, and physicochemical characterization.

    Science.gov (United States)

    Spelios, Michael; Savva, Michalakis

    2008-01-01

    Novel N,N'-diacyl-1,3-diaminopropyl-2-carbamoyl bivalent cationic lipids were synthesized and their physicochemical properties in lamellar assemblies with and without plasmid DNA were evaluated to elucidate the structural requirements of these double-chained pH-sensitive surfactants for potent non-viral gene delivery and expression. The highest in vitro transfection efficacies were induced at +/-4:1 by the dimyristoyl, dipalmitoyl and dioleoyl derivatives 1,3lb2, 1,3lb3 and 1,3lb5, respectively, without inclusion of helper lipids. Transfection activities were reduced in the presence of either 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine alone or in combination with cholesterol for all derivatives except 1,3lb5, which maintained reporter gene expression levels at +/-4:1 and yielded increased lipofection activity at a lower charge ratio of +/-2:1. Ethidium bromide displacement indicated efficient plasmid DNA binding and compaction by the transfection-competent analogs. Dynamic light-scattering and electrophoretic mobility studies revealed lipoplexes of the active lipids with large particle sizes (mean diameter>or=500 nm) and zeta potentials with positive values (low ionic strength) or below neutrality (high ionic strength). Langmuir film balance studies showed high in-plane elasticity of these derivatives in isolation. In agreement with the monolayer experiments, fluorescence polarization studies verified the fluid nature of the highly transfection-efficient amphiphiles, with gel-to-liquid crystalline phase transitions below physiological temperature. The active compounds also interacted with endosome-mimicking vesicles to a greater extent than the poorly active derivative 1,3lb4, as revealed by fluorescence resonance energy transfer experiments. Taken together, the results suggest that well-hydrated and highly elastic cationic lipids with increased acyl chain fluidity and minimal cytotoxicity elicit high transfection activity.

  3. Gene transfection mediated by polyethyleneimine-polyethylene glycol nanocarrier prevents cisplatin-induced spiral ganglion cell damage

    Directory of Open Access Journals (Sweden)

    Guan-gui Chen

    2015-01-01

    Full Text Available Polyethyleneimine-polyethylene glycol (PEI-PEG, a novel nanocarrier, has been used for transfection and gene therapy in a variety of cells. In our previous study, we successfully carried out PEI-PEG-mediated gene transfer in spiral ganglion cells. It remains unclear whether PEI-PEG could be used for gene therapy with X-linked inhibitor of apoptosis protein (XIAP in the inner ear. In the present study, we performed PEI-PEG-mediated XIAP gene transfection in the cochlea of Sprague-Dawley rats, via scala tympani fenestration, before daily cisplatin injections. Auditory brainstem reflex tests demonstrated the protective effects of XIAP gene therapy on auditory function. Immunohistochemical staining revealed XIAP protein expression in the cytoplasm of cells in the spiral ganglion, the organ of Corti and the stria vascularis. Reverse transcription-PCR detected high levels of XIAP mRNA expression in the cochlea. The present findings suggest that PEI-PEG nanocarrier-mediated XIAP gene transfection results in XIAP expression in the cochlea, prevents damage to cochlear spiral ganglion cells, and protects hearing.

  4. In vitro and in vivo gene delivery using chitosan/hyaluronic acid nanoparticles: Influences of molecular mass of hyaluronic acid and lyophilization on transfection efficiency.

    Science.gov (United States)

    Sato, Toshinori; Nakata, Mitsuhiro; Yang, Zhihong; Torizuka, Yu; Kishimoto, Satoko; Ishihara, Masayuki

    2017-08-01

    Lyophilization is an effective method for preserving nonviral gene vectors. To improve the stability and transgene expression of lyophilized plasmid DNA (pDNA) complexes, we coated the surfaces of pDNA/chitosan complexes with hyaluronic acid (HA) of varying molecular masses. The transgene expression of pDNA/chitosan/HA ternary complexes was characterized in vitro and in vivo. pDNA complexes were lyophilized overnight and the resultant products with spongy, porous consistencies were stored at -30, 4 or 25°C for 2 weeks. Rehydrated complexes were characterized using gel retardation assays, aiming to confirm complex formation, measure particle size and evaluate zeta potential, as well as conduct luciferase gene reporter assays. The anti-tumor effects of pDNA ternary complexes were evaluated using suicide gene (pTK) coding thymidine kinase in Huh7-implanted mice. Transfection efficiencies of pDNA/chitosan/HA ternary complexes were dependent on the average molecular masses of HA. The coating of pDNA/chitosan complexes with HA maintained the cellular transfection efficiencies of lyophilized pDNA ternary complexes. Furthermore, intratumoral injection of lyophilized, rehydrated pDNA ternary complexes into tumor-bearing mice showed a significant suppression of tumor growth. The coating of pDNA/chitosan complexes with high-molecular-weight HA augmented the stability and cellular transfection ability of the complexes after lyophilization-rehydration. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Cellular Injury of Cardiomyocytes during Hepatocyte Growth Factor Gene Transfection with Ultrasound-Triggered Bubble Liposome Destruction

    Directory of Open Access Journals (Sweden)

    Kazuo Komamura

    2011-01-01

    Full Text Available We transfected naked HGF plasmid DNA into cultured cardiomyocytes using a sonoporation method consisting of ultrasound-triggered bubble liposome destruction. We examined the effects on transfection efficiency of three concentrations of bubble liposome (1×106, 1×107, 1×108/mL, three concentrations of HGF DNA (60, 120, 180 μg/mL, two insonification times (30, 60 sec, and three incubation times (15, 60, 120 min. We found that low concentrations of bubble liposome and low concentrations of DNA provided the largest amount of the HGF protein expression by the sonoporated cardiomyocytes. Variation of insonification and incubation times did not affect the amount of product. Following insonification, cardiomyocytes showed cellular injury, as determined by a dye exclusion test. The extent of injury was most severe with the highest concentration of bubble liposome. In conclusion, there are some trade-offs between gene transfection efficiency and cellular injury using ultrasound-triggered bubble liposome destruction as a method for gene transfection.

  6. The effects of MicroRNA transfections on global patterns of gene expression in ovarian cancer cells are functionally coordinated

    Directory of Open Access Journals (Sweden)

    Shahab Shubin W

    2012-08-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are a class of small RNAs that have been linked to a number of diseases including cancer. The potential application of miRNAs in the diagnostics and therapeutics of ovarian and other cancers is an area of intense interest. A current challenge is the inability to accurately predict the functional consequences of exogenous modulations in the levels of potentially therapeutic miRNAs. Methods In an initial effort to systematically address this issue, we conducted miRNA transfection experiments using two miRNAs (miR-7, miR-128. We monitored the consequent changes in global patterns of gene expression by microarray and quantitative (real-time polymerase chain reaction. Network analysis of the expression data was used to predict the consequence of each transfection on cellular function and these predictions were experimentally tested. Results While ~20% of the changes in expression patterns of hundreds to thousands of genes could be attributed to direct miRNA-mRNA interactions, the majority of the changes are indirect, involving the downstream consequences of miRNA-mediated changes in regulatory gene expression. The changes in gene expression induced by individual miRNAs are functionally coordinated but distinct between the two miRNAs. MiR-7 transfection into ovarian cancer cells induces changes in cell adhesion and other developmental networks previously associated with epithelial-mesenchymal transitions (EMT and other processes linked with metastasis. In contrast, miR-128 transfection induces changes in cell cycle control and other processes commonly linked with cellular replication. Conclusions The functionally coordinated patterns of gene expression displayed by different families of miRNAs have the potential to provide clinicians with a strategy to treat cancers from a systems rather than a single gene perspective.

  7. Tissue-specific expression of transfected human insulin genes in pluripotent clonal rat insulinoma lines induced during passage in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, O.D.; Andersen, L.C.; Michelsen, B.; Owerbach, D.; Larsson, L.I.; Lernmark, A.; Steiner, D.F. (Hagedorn Research Laboratory, Gentofte (Denmark))

    1988-09-01

    The pluripotent rat islet tumor cell line MSL-G2 expresses primarily glucagon or cholecystokinin and not insulin in vitro but changes phenotype completely after prolonged in vivo cultivation to yield small-sized hypoglycemic tumors composed almost entirely of insulin-producing beta cells. When a genomic DNA fragment containing the coding and upstream regulatory regions of the human insulin gene was stably transfected into MSL-G2 cells no measurable amounts of insulin or insulin mRNA were detected in vitro. However, successive transplantation of two transfected clones resulted in hypoglycemic tumors that efficiently coexpressed human and rat insulin as determined by human C-peptide-specific immunoreagents. These results demonstrate that cis-acting tissue-specific insulin gene enhancer elements are conserved between rat and human insulin genes. The authors propose that the in vivo differentiation of MSL-G2 cells and transfected subclones into insulin-producing cells reflects processes of natural beta-cell ontogeny leading to insulin gene expression.

  8. Tissue-specific expression of transfected human insulin genes in pluripotent clonal rat insulinoma lines induced during passage in vivo

    International Nuclear Information System (INIS)

    Madsen, O.D.; Andersen, L.C.; Michelsen, B.; Owerbach, D.; Larsson, L.I.; Lernmark, A.; Steiner, D.F.

    1988-01-01

    The pluripotent rat islet tumor cell line MSL-G2 expresses primarily glucagon or cholecystokinin and not insulin in vitro but changes phenotype completely after prolonged in vivo cultivation to yield small-sized hypoglycemic tumors composed almost entirely of insulin-producing beta cells. When a genomic DNA fragment containing the coding and upstream regulatory regions of the human insulin gene was stably transfected into MSL-G2 cells no measurable amounts of insulin or insulin mRNA were detected in vitro. However, successive transplantation of two transfected clones resulted in hypoglycemic tumors that efficiently coexpressed human and rat insulin as determined by human C-peptide-specific immunoreagents. These results demonstrate that cis-acting tissue-specific insulin gene enhancer elements are conserved between rat and human insulin genes. The authors propose that the in vivo differentiation of MSL-G2 cells and transfected subclones into insulin-producing cells reflects processes of natural beta-cell ontogeny leading to insulin gene expression

  9. IL-1RA gene-transfected bone marrow-derived mesenchymal stem cells in APA microcapsules could alleviate rheumatoid arthritis.

    Science.gov (United States)

    Hu, Jianhua; Li, Hongjian; Chi, Guanhao; Yang, Zhao; Zhao, Yi; Liu, Wei; Zhang, Chao

    2015-01-01

    In order to investigate the encapsulation of interleukin 1 receptor antagonist (IL-RA) gene-modified mesenchymal stem cells (MSCs) in alginate-poly-L-lysine (APA) microcapsules for the persistent delivery of interleukin 1 receptor antagonist (IL-RA) to treat Rheumatoid arthritis (RA). We transfect mesenchymal stem cells with IL-RA gene, and quantify the IL-RA proteins released from the encapsulated cells followed by microencapsulation of recombinant mesenchymal stem cells, and thus observe the permeability of APA microcapsules and evaluate clinical effects after induction and treatment of collagen-induced arthritis (CIA). The concentration of IL-RA in the supernatant was determined by IL-RA ELISA kit by run in technical triplicates using samples from three separate mice. Encapsulated IL-RA gene-transfected cells were capable of constitutive delivery of IL-RA proteins for at least 30 days. Moreover, the APA microcapsules could inhibit the permeation of fluorescein isothiocyanate-conjuncted immunoglobulin G. Also, it has been found that the APA microcapsules can significantly attenuate collagen induced arthritis after delivering of APA microcapsules to rats. Our results demonstrated that the nonautologous IL-RA gene-transfected stem cells are of potential utility for RA therapy.

  10. DNA repair in human fibroblasts, as reflected by host-cell reactivation of a transfected UV-irradiated luciferase gene, is not related to donor age

    International Nuclear Information System (INIS)

    Merkle, Thomas J.; O'Brien, Katherine; Brooks, Philip J.; Tarone, Robert E.; Robbins, Jay H.

    2004-01-01

    The effect of donor age on the ability of mammalian cells to repair ultraviolet (UV)-induced DNA damage has been studied using several approaches, most recently via assays that measure the host-cell reactivation (HCR) of UV-irradiated reporter gene-containing plasmid vectors following their transfection into cells. Plasmid HCR assays indirectly quantify a cell line's ability to perform nucleotide excision repair (NER) by measuring the enzyme activity of the repaired reporter gene, e.g., chloramphenical acetyltransferase (cat) or luciferase (luc), and are useful in studies investigating whether increasing age may be a risk factor for the deficient repair of potentially cancer-causing, sunlight-induced, DNA lesions in skin cells. In our study, we quantified the DNA repair ability of cultured, nontransformed, human skin fibroblast lines through their HCR of a transfected UV-C-irradiated plasmid containing luc. HCR was measured at various times after transfection in five lines from normal donors of ages 21-96 years, and from one donor who had xeroderma pigmentosum (XP). The normal lines displayed increasing HCR at successive post-transfection time points and showed no significant correlation between HCR and donor age. The XP-A line, known to be markedly deficient in NER of UV-induced DNA damage, showed minimal evidence of HCR compared to the normal lines. To further assess potential variation in HCR with donor age, fibroblast lines from five old donors, ages 84-94 years, were compared with lines from five young donors, ages 17-26 years. While significant differences in HCR were found between some lines, no significant difference was found between the young and old age groups (P=0.44). Our study provides no indication that the higher incidence of skin cancer observed with increasing age is due to an age-related decrease in the ability to repair UV-induced DNA damage

  11. DNA repair in human fibroblasts, as reflected by host-cell reactivation of a transfected UV-irradiated luciferase gene, is not related to donor age

    Energy Technology Data Exchange (ETDEWEB)

    Merkle, Thomas J.; O' Brien, Katherine; Brooks, Philip J.; Tarone, Robert E.; Robbins, Jay H

    2004-10-04

    The effect of donor age on the ability of mammalian cells to repair ultraviolet (UV)-induced DNA damage has been studied using several approaches, most recently via assays that measure the host-cell reactivation (HCR) of UV-irradiated reporter gene-containing plasmid vectors following their transfection into cells. Plasmid HCR assays indirectly quantify a cell line's ability to perform nucleotide excision repair (NER) by measuring the enzyme activity of the repaired reporter gene, e.g., chloramphenical acetyltransferase (cat) or luciferase (luc), and are useful in studies investigating whether increasing age may be a risk factor for the deficient repair of potentially cancer-causing, sunlight-induced, DNA lesions in skin cells. In our study, we quantified the DNA repair ability of cultured, nontransformed, human skin fibroblast lines through their HCR of a transfected UV-C-irradiated plasmid containing luc. HCR was measured at various times after transfection in five lines from normal donors of ages 21-96 years, and from one donor who had xeroderma pigmentosum (XP). The normal lines displayed increasing HCR at successive post-transfection time points and showed no significant correlation between HCR and donor age. The XP-A line, known to be markedly deficient in NER of UV-induced DNA damage, showed minimal evidence of HCR compared to the normal lines. To further assess potential variation in HCR with donor age, fibroblast lines from five old donors, ages 84-94 years, were compared with lines from five young donors, ages 17-26 years. While significant differences in HCR were found between some lines, no significant difference was found between the young and old age groups (P=0.44). Our study provides no indication that the higher incidence of skin cancer observed with increasing age is due to an age-related decrease in the ability to repair UV-induced DNA damage.

  12. Biodegradable gadolinium-chelated cationic poly(urethane amide) copolymers for gene transfection and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Gao, Xiaolong; Wang, Gangmin; Shi, Ting; Shao, Zhihong; Zhao, Peng; Shi, Donglu; Ren, Jie; Lin, Chao; Wang, Peijun

    2016-01-01

    Theranostic nano-polyplexes containing gene and imaging agents hold a great promise for tumor diagnosis and therapy. In this work, we develop a group of new gadolinium (Gd)-chelated cationic poly(urethane amide)s for gene delivery and T 1 -weighted magnetic resonance (MR) imaging. Cationic poly(urethane amide)s (denoted as CPUAs) having multiple disulfide bonds, urethane and amide linkages were synthesized by stepwise polycondensation reaction between 1,4-bis(3-aminopropyl)piperazine and a mixture of di(4-nitrophenyl)-2, 2′-dithiodiethanocarbonate (DTDE-PNC) and diethylenetriaminepentaacetic acid (DTPA) dianhydride at varied molar ratios. Then, Gd-chelated CPUAs (denoted as GdCPUAs) were produced by chelating Gd(III) ions with DTPA residues of CPUAs. These GdCPUAs could condense gene into nanosized and positively-charged polyplexes in a physiological condition and, however, liberated gene in an intracellular reductive environment. In vitro transfection experiments revealed that the GdCPUA at a DTDE-PNC/DTPA residue molar ratio of 85/15 induced the highest transfection efficiency in different cancer cells. This efficiency was higher than that yielded with 25 kDa branched polyethylenimine as a positive control. GdCPUAs and their polyplexes exhibited low cytotoxicity when an optimal transfection activity was detected. Moreover, GdCPUAs may serve as contrast agents for T 1 -weighted magnetic resonance imaging. The results of this work indicate that biodegradable Gd-chelated cationic poly(urethane amide) copolymers have high potential for tumor theranostics. - Highlights: • Novel cationic gadolinium-chelated poly(urethane amide)s (GdCPUAs) are prepared. • GdCPUAs can induce a high transfection efficacy in different cancer cells. • GdCPUAs reveal good cyto-compatibility against cancer cells. • GdCPUAs may be applied as T 1 -contrast agents for magnetic resonance imaging. • GdCPUAs hold high potential for cancer theranostics.

  13. Mechanism of gene transfection by polyamidoamine (PAMAM) dendrimers modified with ornithine residues.

    Science.gov (United States)

    Kumar, Ajay; Yellepeddi, Venkata K; Vangara, Kiran K; Strychar, Kevin B; Palakurthi, Srinath

    2011-11-01

    The aim of this study was to prepare and investigate the mechanism of uptake of the dendriplexes prepared with ornithine-conjugated polyamidoamine (PAMAM) G4 dendrimers. Ornithine-conjugated PAMAMG4 dendrimers were prepared by Fmoc synthesis. A comparative transfection study in NCI H157G cells and polyamine transport-deficient cell line NCI H157R was performed to confirm the role of the polyamine transporter system (PAT) in the dendriplex uptake. Transfection efficiency significantly increased with increase in generation number and extent of ornithine conjugation. Transfection efficiency of the PAMAMG4-ORN60 dendrimers significantly decreased in presence of excess of ornithine (P dendrimers. Transfection efficiency of PAMAMG4-ORN60 was significantly low in NCI H157R (31.66 ± 3.95%, RFU: 17.87 ± 1.34) as compared to NCI H157G cell line (63.07 ± 6.8%, relative fluorescence units (RFU): 23.28 ± 0.66). Results indicate the role of PAT in addition to charge-mediated endocytosis in the internalization of ornithine-conjugated PAMAMG4 dendrimers. Cytotoxicity analysis (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay) in human embryonic kidney cell line (HEK) 293T cells showed that the dendriplexes were non-toxic at N/P 10.

  14. Biodegradable gadolinium-chelated cationic poly(urethane amide) copolymers for gene transfection and magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Xiaolong [Department of Radiology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065 (China); Wang, Gangmin [Department of Urology, Huashan Hospital, Fudan University, Shanghai 200040 (China); Shi, Ting [The Institute for Translational Nanomedicine, Shanghai East Hospital, Institute for Biomedical Engineering and Nanoscience, Tongji University School of Medicine, Shanghai 200092 (China); Shao, Zhihong [Department of Radiology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065 (China); Zhao, Peng; Shi, Donglu [The Institute for Translational Nanomedicine, Shanghai East Hospital, Institute for Biomedical Engineering and Nanoscience, Tongji University School of Medicine, Shanghai 200092 (China); Ren, Jie [Institute of Nano and Biopolymeric Materials, School of Materials Science and Engineering, Tongji University, 4800 Caoan Road, Shanghai 201804 (China); Lin, Chao, E-mail: chaolin@tongji.edu.cn [The Institute for Translational Nanomedicine, Shanghai East Hospital, Institute for Biomedical Engineering and Nanoscience, Tongji University School of Medicine, Shanghai 200092 (China); Wang, Peijun, E-mail: tjpjwang@sina.com [Department of Radiology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065 (China)

    2016-08-01

    Theranostic nano-polyplexes containing gene and imaging agents hold a great promise for tumor diagnosis and therapy. In this work, we develop a group of new gadolinium (Gd)-chelated cationic poly(urethane amide)s for gene delivery and T{sub 1}-weighted magnetic resonance (MR) imaging. Cationic poly(urethane amide)s (denoted as CPUAs) having multiple disulfide bonds, urethane and amide linkages were synthesized by stepwise polycondensation reaction between 1,4-bis(3-aminopropyl)piperazine and a mixture of di(4-nitrophenyl)-2, 2′-dithiodiethanocarbonate (DTDE-PNC) and diethylenetriaminepentaacetic acid (DTPA) dianhydride at varied molar ratios. Then, Gd-chelated CPUAs (denoted as GdCPUAs) were produced by chelating Gd(III) ions with DTPA residues of CPUAs. These GdCPUAs could condense gene into nanosized and positively-charged polyplexes in a physiological condition and, however, liberated gene in an intracellular reductive environment. In vitro transfection experiments revealed that the GdCPUA at a DTDE-PNC/DTPA residue molar ratio of 85/15 induced the highest transfection efficiency in different cancer cells. This efficiency was higher than that yielded with 25 kDa branched polyethylenimine as a positive control. GdCPUAs and their polyplexes exhibited low cytotoxicity when an optimal transfection activity was detected. Moreover, GdCPUAs may serve as contrast agents for T{sub 1}-weighted magnetic resonance imaging. The results of this work indicate that biodegradable Gd-chelated cationic poly(urethane amide) copolymers have high potential for tumor theranostics. - Highlights: • Novel cationic gadolinium-chelated poly(urethane amide)s (GdCPUAs) are prepared. • GdCPUAs can induce a high transfection efficacy in different cancer cells. • GdCPUAs reveal good cyto-compatibility against cancer cells. • GdCPUAs may be applied as T{sub 1}-contrast agents for magnetic resonance imaging. • GdCPUAs hold high potential for cancer theranostics.

  15. Real-time impedimetric monitoring of Poly(ethylenimine)s-mediated cytotoxicity during gene transfection

    DEFF Research Database (Denmark)

    Caviglia, Claudia; Carminati, Marco; Heiskanen, Arto

    Poly(ethylenimine)s (PEIs) are able to condense DNA and RNA into stable toroidal and globular nanostructures (polyplexes) and are among the most efficient and promising synthetic transfectants, but they induce severe cytotoxicity. The mechanisms of PEI-mediated cytotoxicity have not been fully...... delineated but PEI toxicity appears to predominantly depend on membrane perturbing effects in cellular compartments in which they accumulate. Electrochemical Impedance Spectroscopy (EIS) is used as a non-invasive biophysical approach for the investigation of the electrical properties of biological materials...

  16. Target gene expression levels and competition between transfected and endogenous microRNAs are strong confounding factors in microRNA high-throughput experiments

    Science.gov (United States)

    2012-01-01

    Background MicroRNA (miRNA) target genes tend to have relatively long and conserved 3' untranslated regions (UTRs), but to what degree these characteristics contribute to miRNA targeting is poorly understood. Different high-throughput experiments have, for example, shown that miRNAs preferentially regulate genes with both short and long 3' UTRs and that target site conservation is both important and irrelevant for miRNA targeting. Results We have analyzed several gene context-dependent features, including 3' UTR length, 3' UTR conservation, and messenger RNA (mRNA) expression levels, reported to have conflicting influence on miRNA regulation. By taking into account confounding factors such as technology-dependent experimental bias and competition between transfected and endogenous miRNAs, we show that two factors - target gene expression and competition - could explain most of the previously reported experimental differences. Moreover, we find that these and other target site-independent features explain about the same amount of variation in target gene expression as the target site-dependent features included in the TargetScan model. Conclusions Our results show that it is important to consider confounding factors when interpreting miRNA high throughput experiments and urge special caution when using microarray data to compare average regulatory effects between groups of genes that have different average gene expression levels. PMID:22325809

  17. Transfection of Eimeria mitis with yellow fluorescent protein as reporter and the endogenous development of the transgenic parasite.

    Directory of Open Access Journals (Sweden)

    Mei Qin

    Full Text Available BACKGROUND: Advancements have been made in the genetic manipulation of apicomplexan parasites. Both the in vitro transient and in vivo stable transfection of Eimeria tenella have been developed successfully. Herein, we report the transient and stable transfection of Eimeria mitis. METHODS AND FINDINGS: Sporozoites of E. mitis transfected with enhanced yellow fluorescent protein (EYFP expression plasmid were inoculated into chickens via the cloacal route. The recovered fluorescent oocysts were sorted by fluorescence activated cell sorting (FACS and then passaged 6 generations successively in chickens. The resulting population was analyzed by genome walking and Western blot. The endogenous development of the transgenic E. mitis was observed and its reproduction potential was tested. The stable transfection of E. mitis was developed. Genome walking confirmed the random integration of plasmid DNA into the genome; while Western blot analysis demonstrated the expression of foreign proteins. Constitutive expression of EYFP was observed in all stages of merogony, gametogony and sporogony. The peak of the transgenic oocyst output was delayed by 24 h and the total oocyst reproduction was reduced by 7-fold when compared to the parental strain. CONCLUSION: Stable transfection of E. mitis was successfully developed. The expression of foreign antigens in the transgenic parasites will facilitate the development of transgenic E. mitis as a vaccine vector.

  18. The effects of human TSH receptor gene transfection on iodide uptake and thyroid-specific gene expression in poorly differentiated thyroid carcinoma cell line

    International Nuclear Information System (INIS)

    Hou Shasha; Wang Hui; Feng Fang; Lin Ning; Fu Hongliang; Du Xueliang; Wu Jingchuan

    2011-01-01

    Objective: To investigate the changes of iodide uptake and the expression of thyroid-specific genes in poorly differentiated follicular thyroid carcinoma (FTC) cells after transfection of human TSH receptor (hTSHR) gene in vitro. Methods: The recombinant eukaryotic expression plasmid PcDNA3.1/hTSHR-cDNA was transformed into DH 5a bacterial for amplification and then the recombinant plasmid was extracted. The recombinant was identified with PCR amplifying, restriction enzyme digestion analysis and DNA sequencing. The recombinant plasmid pcDNA3.1/hTSHR was transfected into FTC-133 cell line by lipofectin method in vitro. Immunofluorescence, iodide uptake studies and real time-PCR were applied to detect target protein expression. Statistical analysis was performed with t-test using SPSS 13.0 software. Results: Kpn I and Xba I restriction enzyme digestion, PCR amplifying and DNA sequencing confirmed that pcDNA3.1/hTSHR was successfully constructed. After transfection of the recombinant plasmid pcDNA3.1/hTSHR-cDNA and the stimulation of hTSH, the tumor cells displayed the expression of hTSHR protein at cell surface and cytoplasm. The iodine uptake in pcDNA3.1/hTSHR transfected cells was 2.9 times higher than that of control(pcDNA3.1(+) transfected cells) group(t = 28.63, P<0.01). The expression of TSHR, NIS, TPO and Tg (mRNA levels) in pcDNA3.1/hTSHR transfected cells were also significantly elevated by 1.74 (t =5.959, P<0.01), 7.2 (t =3.807, P<0.05), 2.88 (t=4.769, P<0.01) and 2.67 times (t=6.388, P<0.01) respectively compared to those of the control group. Conclusion: The study demonstrates that iodide uptake may be reactivated by hTSHR receptor gene transfection in poorly differentiated FTC cell. (authors)

  19. Autologous glioma cell vaccine admixed with interleukin-4 gene transfected fibroblasts in the treatment of patients with malignant gliomas

    Directory of Open Access Journals (Sweden)

    Torres-Trejo Alejandro

    2007-12-01

    Full Text Available Abstract Background The prognosis for malignant gliomas remains dismal. We addressed the safety, feasibility and preliminary clinical activity of the vaccinations using autologous glioma cells and interleukin (IL-4 gene transfected fibroblasts. Methods In University of Pittsburgh Cancer Institute (UPCI protocol 95-033, adult participants with recurrent glioblastoma multiforme (GBM or anaplastic astrocytoma (AA received gross total resection (GTR of the recurrent tumors, followed by two vaccinations with autologous fibroblasts retrovirally transfected with TFG-IL4-Neo-TK vector admixed with irradiated autologous glioma cells. In UPCI 99-111, adult participants with newly diagnosed GBM or AA, following GTR and radiation therapy, received two intradermal vaccinations with the TFG-IL4-Neo-TK-transfected fibroblasts admixed with type-1 dendritic cells (DC loaded with autologous tumor lysate. The participants were evaluated for occurrence of adverse events, immune response, and clinical response by radiological imaging. Results and Discussion In UPCI 95-033, only 2 of 6 participants received the vaccinations. Four other participants were withdrawn from the trial because of tumor progression prior to production of the cellular vaccine. However, both participants who received two vaccinations demonstrated encouraging immunological and clinical responses. Biopsies from the local vaccine sites from one participant displayed IL-4 dose-dependent infiltration of CD4+ as well as CD8+ T cells. Interferon (IFN-γ Enzyme-Linked Immuno-SPOT (ELISPOT assay in another human leukocyte antigen (HLA-A2+ participant demonstrated systemic T-cell responses against an HLA-A2-restricted glioma-associated antigen (GAA epitope EphA2883–891. Moreover, both participants demonstrated clinical and radiological improvement with no evidence of allergic encephalitis, although both participants eventually succumbed with the tumor recurrence. In 99-111, 5 of 6 enrolled participants

  20. Multifunctional non-viral gene vectors with enhanced stability, improved cellular and nuclear uptake capability, and increased transfection efficiency

    Science.gov (United States)

    Yang, Zhe; Jiang, Zhaozhong; Cao, Zhong; Zhang, Chao; Gao, Di; Luo, Xingen; Zhang, Xiaofang; Luo, Huiyan; Jiang, Qing; Liu, Jie

    2014-08-01

    We have developed a new multifunctional, non-viral gene delivery platform consisting of cationic poly(amine-co-ester) (PPMS) for DNA condensation, PEG shell for nanoparticle stabilization, poly(γ-glutamic acid) (γ-PGA) and mTAT (a cell-penetrating peptide) for accelerated cellular uptake, and a nuclear localization signal peptide (NLS) for enhanced intracellular transport of DNA to the nucleus. In vitro study showed that coating of the binary PPMS/DNA polyplex with γ-PGA promotes cellular uptake of the polyplex particles, particularly by γ-glutamyl transpeptidase (GGT)-positive cells through the GGT-mediated endocytosis pathway. Conjugating PEG to the γ-PGA led to the formation of a ternary PPMS/DNA/PGA-g-PEG polyplex with decreased positive charges on the surface of the polyplex particles and substantially higher stability in serum-containing aqueous medium. The cellular uptake rate was further improved by incorporating mTAT into the ternary polyplex system. Addition of the NLS peptide was designed to facilitate intracellular delivery of the plasmid to the nucleus--a rate-limiting step in the gene transfection process. As a result, compared with the binary PPMS/LucDNA polyplex, the new mTAT-quaternary PPMS/LucDNA/NLS/PGA-g-PEG-mTAT system exhibited reduced cytotoxicity, remarkably faster cellular uptake rate, and enhanced transport of DNA to the nucleus. All these advantageous functionalities contribute to the remarkable gene transfection efficiency of the mTAT-quaternary polyplex both in vitro and in vivo, which exceeds that of the binary polyplex and commercial Lipofectamine™ 2000/DNA lipoplex. The multifunctional mTAT-quaternary polyplex system with improved efficiency and reduced cytotoxicity represents a new type of promising non-viral vectors for the delivery of therapeutic genes to treat tumors.We have developed a new multifunctional, non-viral gene delivery platform consisting of cationic poly(amine-co-ester) (PPMS) for DNA condensation, PEG shell

  1. Restoration of u.v.-induced excision repair in Xeroderma D cells transfected with the denV gene of bacteriophage T4

    International Nuclear Information System (INIS)

    Arrand, J.E.; Squires, S.; Bone, N.M.; Johnson, R.T.

    1987-01-01

    The heritable DNA repair defect in human Xeroderma D cells, resulting in failure to incise at u.v. light-induced pyrimidine dimers, has been partially but stably corrected by transfection of immortalised cells with the denV pyrimidine dimer glycosylase gene of bacteriophage T4. Transfectants selected either for a dominant marker on the mammalian vector carrying the prokaryotic gene or for dominant marker plus resistance to killing by u.v. light, were shown to express the denV gene to varying degrees. denV expression results in significant phenotypic change in the initially repair-deficient, u.v.-hypersensitive cells. Increased resistance to u.v. light and more rapid recovery of replicative DNA synthesis following u.v. irradiation were correlated with improved repair DNA synthesis and with a novel dimer incision capability present in denV transfected Xeroderma cells but not as evident in transfected normal cells. Most transfectants contain a single integrated copy of the denV gene; increase in denV copy number does not result in either increased gene expression or enhanced survival to u.v. light. Results show that expression of a heterologous prokaryotic repair gene can partially compensate for the genetic defect in a human Xeroderma D cell. (author)

  2. Identification of valid reference genes for the normalization of RT-qPCR expression studies in human breast cancer cell lines treated with and without transient transfection.

    Directory of Open Access Journals (Sweden)

    Lin-Lin Liu

    Full Text Available Reverse transcription-quantitative polymerase chain reaction (RT-qPCR is a powerful technique for examining gene expression changes during tumorigenesis. Target gene expression is generally normalized by a stably expressed endogenous reference gene; however, reference gene expression may differ among tissues under various circumstances. Because no valid reference genes have been documented for human breast cancer cell lines containing different cancer subtypes treated with transient transfection, we identified appropriate and reliable reference genes from thirteen candidates in a panel of 10 normal and cancerous human breast cell lines under experimental conditions with/without transfection treatments with two transfection reagents. Reference gene expression stability was calculated using four algorithms (geNorm, NormFinder, BestKeeper and comparative delta Ct, and the recommended comprehensive ranking was provided using geometric means of the ranking values using the RefFinder tool. GeNorm analysis revealed that two reference genes should be sufficient for all cases in this study. A stability analysis suggests that 18S rRNA-ACTB is the best reference gene combination across all cell lines; ACTB-GAPDH is best for basal breast cancer cell lines; and HSPCB-ACTB is best for ER+ breast cancer cells. After transfection, the stability ranking of the reference gene fluctuated, especially with Lipofectamine 2000 transfection reagent in two subtypes of basal and ER+ breast cell lines. Comparisons of relative target gene (HER2 expression revealed different expressional patterns depending on the reference genes used for normalization. We suggest that identifying the most stable and suitable reference genes is critical for studying specific cell lines under certain circumstances.

  3. Loss of retrovirus production in JB/RH melanoma cells transfected with H-2Kb and TAP-1 genes.

    Science.gov (United States)

    Li, M; Xu, F; Muller, J; Huang, X; Hearing, V J; Gorelik, E

    1999-01-20

    JB/RH1 melanoma cells, as well as other melanomas of C57BL/6 mice (B16 and JB/MS), express a common melanoma-associated antigen (MAA) encoded by an ecotropic melanoma-associated retrovirus (MelARV). JB/RH1 cells do not express the H-2Kb molecules due to down-regulation of the H-2Kb and TAP-1 genes. When JB/RH1 cells were transfected with the H-2Kb and cotransfected with the TAP-1 gene, it resulted in the appearance of H-2Kb molecules and an increase in their immunogenicity, albeit they lost expression of retrovirus-encoded MAA recognized by MM2-9B6 mAb. Loss of MAA was found to result from a complete and stable elimination of ecotropic MelARV production in the H-2Kb/TAP-1-transfected JB/RH1 cells. Northern blot analysis showed no differences in ecotropic retroviral messages in MelARV-producing and -nonproducing melanoma cells, suggesting that loss of MelARV production was not due to down-regulation of MelARV transcription. Southern blot analysis revealed several rearrangements in the proviral DNA of H-2Kb-positive JB/RH1 melanoma cells. Sequence analysis of the ecotropic proviral DNA from these cells showed numerous nucleotide substitutions, some of which resulted in the appearance of a novel intraviral PstI restriction site and the loss of a HindIII restriction site in the pol region. PCR amplification of the proviral DNAs indicates that an ecotropic provirus found in the H-2Kb-positive cells is novel and does not preexist in the parental H-2Kb-negative melanoma cells. Conversely, the ecotropic provirus of the parental JB/RH1 cells was not amplifable from the H-2Kb-positive cells. Our data indicate that stable loss of retroviral production in the H-2Kb/TAP-1-transfected melanoma cells is probably due to the induction of recombination between a productive ecotropic MelARV and a defective nonecotropic provirus leading to the generation of a defective ecotropic provirus and the loss of MelARV production and expression of the retrovirus-encoded MAA. Copyright 1999

  4. Single histidine residue in head-group region is sufficient to impart remarkable gene transfection properties to cationic lipids: evidence for histidine-mediated membrane fusion at acidic pH.

    Science.gov (United States)

    Kumar, V V; Pichon, C; Refregiers, M; Guerin, B; Midoux, P; Chaudhuri, A

    2003-08-01

    Presence of endosome-disrupting multiple histidine functionalities in the molecular architecture of cationic polymers, such as polylysine, has previously been demonstrated to significantly enhance their in vitro gene delivery efficiencies. Towards harnessing improved transfection property through covalent grafting of endosome-disrupting single histidine functionality in the molecular structure of cationic lipids, herein, we report on the design, the synthesis and the transfection efficiency of two novel nonglycerol-based histidylated cationic amphiphiles. We found that L-histidine-(N,N-di-n-hexadecylamine)ethylamide (lipid 1) and L-histidine-(N,N-di-n-hexadecylamine,-N-methyl)ethylamide (lipid 2) in combination with cholesterol gave efficient transfections into various cell lines. The transfection efficiency of Chol/lipid 1 lipoplexes into HepG2 cells was two order of magnitude higher than that of FuGENE(TM)6 and DC-Chol lipoplexes, whereas it was similar into A549, 293T7 and HeLa cells. A better efficiency was obtained with Chol/lipid 2 lipoplexes when using the cytosolic luciferase expression vector (pT7Luc) under the control of the bacterial T7 promoter. Membrane fusion activity measurements using fluorescence resonance energy transfer (FRET) technique showed that the histidine head-groups of Chol/lipid 1 liposomes mediated membrane fusion in the pH range 5-7. In addition, the transgene expression results using the T7Luc expression vector convincingly support the endosome-disrupting role of the presently described mono-histidylated cationic transfection lipids and the release of DNA into the cytosol. We conclude that covalent grafting of a single histidine amino acid residue to suitable twin-chain hydrophobic compounds is able to impart remarkable transfection properties on the resulting mono-histidylated cationic amphiphile, presumably via the endosome-disrupting characteristics of the histidine functionalities.

  5. Elucidating the interplay between DNA-condensing and free polycations in gene transfection through a mechanistic study of linear and branched PEI

    DEFF Research Database (Denmark)

    Dai, Zhuojun; Gjetting, Torben; Mattebjerg, Maria Ahlm

    2011-01-01

    In the present study we compare LPEI and BPEI characteristics related to DNA condensation and their role as free polycation chains in gene transfection. Using radioactive 32P labeled DNA, we investigated the effect of free PEI chains on the cellular uptake of polyplexes. Our investigations show d...

  6. A phagocytotic inducer from herbal constituent, pentagalloylglucose enhances lipoplex-mediated gene transfection in dendritic cells.

    Science.gov (United States)

    Kato, Shinichiro; Koizumi, Keiichi; Yamada, Miyuki; Inujima, Akiko; Takeno, Nobuhiro; Nakanishi, Tsuyoshi; Sakurai, Hiroaki; Nakagawa, Shinsaku; Saiki, Ikuo

    2010-01-01

    Antigen-presenting cells are key vehicles for delivering antigens in tumor immunotherapy, and the most potent of them are dendritic cells (DCs). Recent studies have demonstrated the usefulness of DCs genetically modified by lipofection in tumor immune therapy, although sufficient gene transduction into DCs is quite difficult. Here, we show that Paeoniae radix, herbal medicine, and the constituent, 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), have an attractive function to enhance phagocytosis in murine dendritic cell lines, DC2.4 cells. In particular, PGG in combination with lipofectin (LPF) enhanced phagocytic activity. Furthermore, PGG enhanced lipofection efficacy in DC2.4 cells, but not in colorectal carcinoma cell lines, Colon26. In other words, PGG synergistically enhanced the effect of lipofectin-dependent phagocytosis on phagocytic cells. Hence, according to our data, PGG could be an effective aid in lipofection using dendritic cells. Furthermore, these findings provide an expectation that constituents from herbal plant enhance lipofection efficacy.

  7. The effect of aloe emodin–encapsulated nanoliposome-mediated r-caspase-3 gene transfection and photodynamic therapy on human gastric cancer cells

    International Nuclear Information System (INIS)

    Li, Kai-Ting; Duan, Qin-Qin; Chen, Qing; He, Juan-Wen; Tian, Si; Lin, Hai-Dan; Gao, Qing; Bai, Ding-Qun

    2015-01-01

    Gastric carcinoma (GC) has high incidence and mortality rates in China. Surgery and chemotherapy are the main treatments. Photodynamic therapy (PDT) has become a new treatment modality, appearing in recent experimental studies and clinical trials in various tumors. This study explores the combined effect of gene transfection with PDT on GC cells using aloe emodin (AE)–encapsulated nanoliposomes, which acted as gene carrier as well as one photosensitizer (PS). AE-encapsulated nanoliposomes (nano-AE) were prepared by reverse evaporation method. Electron microscopy and nano-ZS90 analyzer were used to detect its morphology, size, and wavelength. Western blot was used to detect the expression of the caspase-3 after transfection. MTT assay and flow cytometry were employed to determine the cytotoxic and apoptotic rates, respectively. Hoechst 33342 staining was adopted to detect the morphological changes in death gastric cancer cells. Cellular reactive oxygen species (ROS) contents were measured by DCFH-DA staining. Outcomes demonstrated that the nano-AE has good properties as gene delivery carriers as well as a PS. The group in which the recombinant plasmid of r-caspase-3 was transfected had higher protein expression of the caspase-3 than controls, meanwhile the proliferation rates of the transfected cells were inhibited by the nano-AE-mediated PDT in an energy-dependent manner. In addition, in the transfected cells, the death rate increased to 77.3% as assessed 12 h after PDT (6.4 J/cm 2 ). Hochest 33342 staining also revealed that the death rate increased significantly in the transfected group compared with other groups. Compared to control groups, the production of ROS in nano-AE PDT group had quadrupled in SGC-7901 cells as early as 1 h after PDT, while it is similar to the group of nano-AE transfection and PDT. Nano-AE-mediated r-caspase-3 gene transfection coupled with PDT could inhibit the proliferation rate and increase the apoptotic rate remarkably in human

  8. Reverse Transfection Using Gold Nanoparticles

    Science.gov (United States)

    Yamada, Shigeru; Fujita, Satoshi; Uchimura, Eiichiro; Miyake, Masato; Miyake, Jun

    Reverse transfection from a solid surface has the potential to deliver genes into various types of cell and tissue more effectively than conventional methods of transfection. We present a method for reverse transfection using a gold colloid (GC) as a nanoscaffold by generating nanoclusters of the DNA/reagentcomplex on a glass surface, which could then be used for the regulation of the particle size of the complex and delivery of DNA into nuclei. With this method, we have found that the conjugation of gold nanoparticles (20 nm in particle size) to the pEGFP-N1/Jet-PEI complex resulted in an increase in the intensity of fluorescence of enhanced green fluorescent protein (EGFP) (based on the efficiency of transfection) from human mesenchymal stem cells (hMSCs), as compared with the control without GC. In this manner, we constructed a method for reverse transfection using GC to deliver genes into the cells effectively.

  9. Intracellular insulin-receptor dissociation and segregation in a rat fibroblast cell line transfected with a human insulin receptor gene

    International Nuclear Information System (INIS)

    Levy, J.R.; Olefsky, J.M.

    1988-01-01

    The cellular processing of insulin and insulin receptors was studied using a rat fibroblast cell line that had been transfected with a normal human insulin receptor gene, expressing approximately 500 times the normal number of native fibroblasts insulin receptors. These cells bind and internalize insulin normally. Biochemically assays based on the selective precipitation by polyethylene glycol of intact insulin-receptor complexes but not of free intracellular insulin were developed to study the time course of intracellular insulin-receptor dissociation. Fibroblasts were incubated with radiolabeled insulin at 4 0 C, and internalization of insulin-receptor complexes was initiated by warming the cells to 37 0 C. Within 2 min, 90% of the internalized radioactivity was composed of intact insulin-receptor complexes. The dissociation of insulin from internalized insulin-receptor complexes was markedly inhibited by monensin and chloroquine. Furthermore, chloroquine markedly increased the number of cross-linkable intracellular insulin-receptor complexes, as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis autoradiography. These findings suggest that acidification of intracellular vesicles is responsible for insulin-receptor dissociation. Physical segregation of dissociated intracellular insulin from its receptor was monitored. The results are consistent with the view that segregation of insulin and receptor occurs 5-10 min after initiation of dissociation. These studies demonstrate the intracellular itinerary of insulin-receptor complexes, including internalization, dissociation of insulin from the internalized receptor within an acidified compartment, segregation of insulin from the receptor, and subsequent ligand degradation

  10. Malignant transformation of diploid human fibroblasts by transfection of oncogenes: Progress report, July 1986--June 1989

    International Nuclear Information System (INIS)

    McCormick, J.J.; Maher, V.M.

    1989-01-01

    Although there is good evidence that carcinogen exposure is a major cause of human cancer, it has proven impossible to transform normal human fibroblasts or epithelial cells in culture into malignant cells by treating them with carcinogens. This failure may reflect an inability to identify and isolate cells containing one or more premalignant changes so that these can be expanded and exposed to carcinogens a second time to induce additional required changes. A second serious roadblock to the sequential introduction of changes and expansion of clonally-derived cells containing such premalignant changes in the finite life span of human cells in culture. Using transfection of specific human oncogenes in a series of specially-selected vectors, we have overcome these obstacles and have recently succeeded in generating an infinite life span diploid human cell strain MSU-1.0, which appears to be normal in all other characteristics. From that cell a second cell strain, MSU-1.1, was generated which we have been able to transform into a malignant state not only by transfecting the cells with oncogenes but also by treating them with chemical carcinogens. We now have evidence that there is not just a single linear process which results in malignant transformation. Rather, cells appear to progress to malignancy on a series of parallel, sometimes overlapping tracks. We now propose to carry out detailed studies of the specific mechanisms of malignant cell transformation using the cell strains available in this laboratory to achieve the goal of building relevant quantitative models of carcinogenesis. 29 refs

  11. Hyperbranched–dendrimer architectural copolymer gene delivery using hyperbranched PEI conjugated to poly(propyleneimine) dendrimers: synthesis, characterization, and evaluation of transfection efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Alavi, Seyyed Jamal [Ferdowsi University of Mashhad, Department of Chemistry, Faculty of Science (Iran, Islamic Republic of); Gholami, Leila [Mashhad University of Medical Sciences, Department of Modern Sciences and Technologies, School of Medicine (Iran, Islamic Republic of); Askarian, Saeedeh [Mashhad University of Medical Sciences, Department of Medical Biotechnology, School of Medicine (Iran, Islamic Republic of); Darroudi, Majid [Mashhad University of Medical Sciences, Nuclear Medicine Research Center (Iran, Islamic Republic of); Massoudi, Abdolhossein [University of Payam noor, Department of Chemistry (Iran, Islamic Republic of); Rezaee, Mehdi; Kazemi Oskuee, Reza, E-mail: Oskueekr@mums.ac.ir [Mashhad University of Medical Sciences, Department of Medical Biotechnology, School of Medicine (Iran, Islamic Republic of)

    2017-02-15

    The applications of dendrimer-based vectors seem to be promising in non-viral gene delivery because of their potential for addressing the problems with viral vectors. In this study, generation 3 poly(propyleneimine) (G3-PPI) dendrimers with 1, 4-diaminobutane as a core initiator was synthesized using a divergent growth approach. To increase the hydrophobicity and reduce toxicity, 10% of primary amines of G3-PPI dendrimers were replaced with bromoalkylcarboxylates with different chain lengths (6-bromohexanoic and 10-bromodecanoic). Then, to retain the overall buffering capacity and enhance transfection, the alkylcarboxylate–PPIs were conjugated to 10 kDa branched polyethylenimine (PEI). The results showed that the modified PPI was able to form complexes with the diameter of less than 60 nm with net-positive surface charge around 20 mV. No significant toxicity was observed in modified PPIs; however, the hexanoate conjugated PPI–PEI (PPI-HEX-10% PEI) and the decanoate conjugated PPI–PEI (PPI-DEC-10%-PEI) showed the best transfection efficiency in murine neuroblastoma (Neuro-2a) cell line, even PPI-HEX-10%-PEI showed transfection efficiency equal to standard PEI 25 kDa with reduced toxicity. This study suggested a new series of hyperbranched (PEI)–dendrimer (PPI) architectural copolymers as non-viral gene delivery vectors with high transfection efficiency and low toxicity.

  12. Hyperbranched-dendrimer architectural copolymer gene delivery using hyperbranched PEI conjugated to poly(propyleneimine) dendrimers: synthesis, characterization, and evaluation of transfection efficiency

    Science.gov (United States)

    Alavi, Seyyed Jamal; Gholami, Leila; Askarian, Saeedeh; Darroudi, Majid; Massoudi, Abdolhossein; Rezaee, Mehdi; Kazemi Oskuee, Reza

    2017-02-01

    The applications of dendrimer-based vectors seem to be promising in non-viral gene delivery because of their potential for addressing the problems with viral vectors. In this study, generation 3 poly(propyleneimine) (G3-PPI) dendrimers with 1, 4-diaminobutane as a core initiator was synthesized using a divergent growth approach. To increase the hydrophobicity and reduce toxicity, 10% of primary amines of G3-PPI dendrimers were replaced with bromoalkylcarboxylates with different chain lengths (6-bromohexanoic and 10-bromodecanoic). Then, to retain the overall buffering capacity and enhance transfection, the alkylcarboxylate-PPIs were conjugated to 10 kDa branched polyethylenimine (PEI). The results showed that the modified PPI was able to form complexes with the diameter of less than 60 nm with net-positive surface charge around 20 mV. No significant toxicity was observed in modified PPIs; however, the hexanoate conjugated PPI-PEI (PPI-HEX-10% PEI) and the decanoate conjugated PPI-PEI (PPI-DEC-10%-PEI) showed the best transfection efficiency in murine neuroblastoma (Neuro-2a) cell line, even PPI-HEX-10%-PEI showed transfection efficiency equal to standard PEI 25 kDa with reduced toxicity. This study suggested a new series of hyperbranched (PEI)-dendrimer (PPI) architectural copolymers as non-viral gene delivery vectors with high transfection efficiency and low toxicity.

  13. Effect of transfection and co-incubation of bovine sperm with exogenous DNA on sperm quality and functional parameters for its use in sperm-mediated gene transfer.

    Science.gov (United States)

    Arias, María Elena; Sánchez-Villalba, Esther; Delgado, Andrea; Felmer, Ricardo

    2017-02-01

    Sperm-mediated gene transfer (SMGT) is based on the capacity of sperm to bind exogenous DNA and transfer it into the oocyte during fertilization. In bovines, the progress of this technology has been slow due to the poor reproducibility and efficiency of the production of transgenic embryos. The aim of the present study was to evaluate the effects of different sperm transfection systems on the quality and functional parameters of sperm. Additionally, the ability of sperm to bind and incorporate exogenous DNA was assessed. These analyses were carried out by flow cytometry and confocal fluorescence microscopy, and motility parameters were also evaluated by computer-assisted sperm analysis (CASA). Transfection was carried out using complexes of plasmid DNA with Lipofectamine, SuperFect and TurboFect for 0.5, 1, 2 or 4 h. The results showed that all of the transfection treatments promoted sperm binding and incorporation of exogenous DNA, similar to sperm incorporation of DNA alone, without affecting the viability. Nevertheless, the treatments and incubation times significantly affected the motility parameters, although no effect on the integrity of DNA or the levels of reactive oxygen species (ROS) was observed. Additionally, we observed that transfection using SuperFect and TurboFect negatively affected the acrosome integrity, and TurboFect affected the mitochondrial membrane potential of sperm. In conclusion, we demonstrated binding and incorporation of exogenous DNA by sperm after transfection and confirmed the capacity of sperm to spontaneously incorporate exogenous DNA. These findings will allow the establishment of the most appropriate method [intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF)] of generating transgenic embryos via SMGT based on the fertilization capacity of transfected sperm.

  14. Gene expression profiles in primary duodenal chick cells following transfection with avian influenza virus H5 DNA plasmid encapsulated in silver nanoparticles

    Directory of Open Access Journals (Sweden)

    Jazayeri SD

    2013-02-01

    Full Text Available Seyed Davoud Jazayeri,1 Aini Ideris,1,2 Kamyar Shameli,3 Hassan Moeini,1 Abdul Rahman Omar1,21Institute of Bioscience, 2Faculty of Veterinary Medicine, 3Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor, MalaysiaAbstract: In order to develop a systemically administered safe and effective nonviral gene delivery system against avian influenza virus (AIV that induced cytokine expression, the hemagglutinin (H5 gene of AIV, A/Ck/Malaysia/5858/04 (H5N1 and green fluorescent protein were cloned into a coexpression vector pIRES (pIREGFP-H5 and formulated using green synthesis of silver nanoparticles (AgNPs with poly(ethylene glycol and transfected into primary duodenal cells taken from 18-day-old specific-pathogen-free chick embryos. The AgNPs were prepared using moderated temperature and characterized for particle size, surface charge, ultraviolet-visible spectra, DNA loading, and stability. AgNPs and AgNP-pIREGFP-H5 were prepared in the size range of 13.9 nm and 25 nm with a positive charge of +78 ± 0.6 mV and +40 ± 6.2 mV, respectively. AgNPs with a positive surface charge could encapsulate pIREGFP-H5 efficiently. The ultraviolet-visible spectra for AgNP-pIREGFP-H5 treated with DNase I showed that the AgNPs were able to encapsulate pIREGFP-H5 efficiently. Polymerase chain reaction showed that AgNP-pIREGFP-H5 entered into primary duodenal cells rapidly, as early as one hour after transfection. Green fluorescent protein expression was observed after 36 hours, peaked at 48 hours, and remained stable for up to 60 hours. In addition, green fluorescent protein expression generally increased with increasing DNA concentration and time. Cells were transfected using Lipocurax in vitro transfection reagent as a positive control. A multiplex quantitative mRNA gene expression assay in the transfected primary duodenal cells via the transfection reagent and AgNPs with pIREGFP-H5 revealed expression of interleukin (IL-18, IL-15, and IL-12

  15. Development of electrochemical reporter assay using HeLa cells transfected with vector plasmids encoding various responsive elements

    Energy Technology Data Exchange (ETDEWEB)

    Shiku, Hitoshi, E-mail: shiku@bioinfo.che.tohoku.ac.jp [Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki-Aoba, Sendai 980-8579 (Japan); Takeda, Michiaki; Murata, Tatsuya [Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki-Aoba, Sendai 980-8579 (Japan); Akiba, Uichi; Hamada, Fumio [Graduate School of Engineering and Resource Science, Akita University, 1-1 Tegata gakuen-machi, Akita 010-8502 (Japan); Matsue, Tomokazu, E-mail: matsue@bioinfo.che.tohoku.ac.jp [Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki-Aoba, Sendai 980-8579 (Japan)

    2009-04-27

    Electrochemical assay using HeLa cell lines transfected with various plasmid vectors encoding SEAP (secreted alkaline phosphatase) as the reporter has been performed by using SECM (scanning electrochemical microscopy). The plasmid vector contains different responsive elements that include GRE (glucocorticoid response elements), CRE (cAMP responsive elements), or {kappa}B (binding site for NF{kappa}B (nuclear factor kappa B)) upstream of the SEAP sequence. The transfected HeLa cells were patterned on a culture dish in a 4 x 4 array of circles of diameter 300 {mu}m by using the PDMS (poly(dimethylsiloxane)) stencil technique. The cellular array was first exposed to 100 ng mL{sup -1} dexamethasone, 10 ng mL{sup -1} forskolin, or 100 ng mL{sup -1} TNF-{alpha} (tumor necrosis factor {alpha}) after which it was further cultured in an RPMI culture medium for 6 h. After incubation, the cellular array was soaked in a measuring solution containing 4.7 mM PAPP (p-aminophenylphosphate) at pH 9.5, following which electrochemical measurements were performed immediately within 40 min. The SECM method allows parallel evaluation of different cell lines transfected with pGRE-SEAP, pCRE-SEAP, and pNF{kappa}B-SEAP patterned on the same solid support for detection of the oxidation current of PAP (p-aminophenol) flux produced from only 300 HeLa cells in each stencil pattern. The results of the SECM method were highly sensitive as compared to those obtained from the conventional CL (chemiluminescence) protocol with at least 5 x 10{sup 4} cells per well.

  16. Ultrasound-targeted transfection of tissue-type plasminogen activator gene carried by albumin nanoparticles to dog myocardium to prevent thrombosis after heart mechanical valve replacement

    Directory of Open Access Journals (Sweden)

    Ji J

    2012-06-01

    Full Text Available Ji Jun, Ji Shang-Yi, Yang Jian-An, He Xia, Yang Xiao-Han, Ling Wen-Ping, Chen Xiao-LingDepartment of Pathology and Cardiovascular Surgery, Shenzhen Sun Yat-Sen Cardiovascular Hospital, Shenzhen, Guangdong, People's Republic of ChinaBackground: There are more than 300,000 prosthetic heart valve replacements each year worldwide. These patients are faced with a higher risk of thromboembolic events after heart valve surgery and long-term or even life-long anticoagulative and antiplatelet therapies are necessary. Some severe complications such as hemorrhaging or rebound thrombosis can occur when the therapy ceases. Tissue-type plasminogen activator (t-PA is a thrombolytic agent. One of the best strategies is gene therapy, which offers a local high expression of t-PA over a prolonged time period to avoid both systemic hemorrhaging and local rebound thrombosis. There are some issues with t-PA that need to be addressed: currently, there is no up-to-date report on how the t-PA gene targets the heart in vivo and the gene vector for t-PA needs to be determined.Aims: To fabricate an albumin nano-t-PA gene ultrasound-targeted agent and investigate its targeting effect on prevention of thrombosis after heart mechanic valve replacement under therapeutic ultrasound.Methods: A dog model of mechanical tricuspid valve replacement was constructed. A highly expressive t-PA gene plasmid was constructed and packaged by nanoparticles prepared with bovine serum albumin. This nanopackaged t-PA gene plasmid was further cross-linked to ultrasonic microbubbles prepared with sucrose and bovine serum albumin to form the ultrasonic-targeted agent for t-PA gene transfection. The agent was given intravenously followed by a therapeutic ultrasound treatment (1 MHz, 1.5 w/cm2, 10 minutes of the heart soon after valve replacement had been performed. The expression of t-PA in myocardium was detected with multiclonal antibodies to t-PA by the indirect immunohistochemical method

  17. Immature transformed rat islet beta-cells differentially express C-peptides derived from the genes coding for insulin I and II as well as a transfected human insulin gene

    DEFF Research Database (Denmark)

    Blume, N; Petersen, J S; Andersen, L C

    1992-01-01

    is induced in the transformed heterogeneous rat islet cell clone, NHI-6F, by transient in vivo passage. During this process a transfected human insulin gene is coactivated with the endogenous nonallelic rat insulin I and II genes. Newly established cultures from NHI-6F insulinomas having a high frequency...

  18. Bone regeneration with active angiogenesis by basic fibroblast growth factor gene transfected mesenchymal stem cells seeded on porous beta-TCP ceramic scaffolds.

    Science.gov (United States)

    Guo, Xiaodong; Zheng, Qixin; Kulbatski, Iris; Yuan, Quan; Yang, Shuhua; Shao, Zengwu; Wang, Hong; Xiao, Baojun; Pan, Zhengqi; Tang, Shuo

    2006-09-01

    Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focused on combining gene transfer with tissue engineering techniques. Basic fibroblast growth factor (bFGF) is one of the most prominent osteogenic growth factors that has the potential to accelerate bone healing by promoting the proliferation and differentiation of mesenchymal stem cells (MSCs) and the regeneration of capillary vasculature. However, the short biological half-lives of growth factors may impose severe restraints on their clinical usefulness. Gene-based delivery systems provide a better way of achieving a sustained high concentration of growth factors locally in the defect and delivering a more biologically active product than that achieved by exogenous application of recombinant proteins. The objective of this experimental study was to investigate whether the bFGF gene modified MSCs could enhance the repair of large segmental bone defects. The pcDNA3-bFGF gene transfected MSCs were seeded on biodegradable porous beta tricalcium phosphate (beta-TCP) ceramics and allografted into the 15 mm critical-sized segmental bone defects in the radius of 18 New Zealand White rabbits. The pcDNA3 vector gene transfected MSCs were taken as the control. The follow-up times were 2, 4, 6, 8, 10 and 12 weeks. Scanning electron microscopic, roentgenographic, histologic and immunohistological studies were used to assess angiogenesis and bone regeneration. In vitro, the proliferation and differentiation of bFGF gene transfected MSCs were more active than that of the control groups. In vivo, significantly more new bone formation accompanied by abundant active capillary regeneration was observed in pores of the ceramics loaded with bFGF gene transfected MSCs, compared with control groups. Transfer of gene encoding bFGF to MSCs increases their osteogenic properties by enhancing capillary regeneration, thus providing a rich blood supply for new bone formation. This new b

  19. Bone regeneration with active angiogenesis by basic fibroblast growth factor gene transfected mesenchymal stem cells seeded on porous {beta}-TCP ceramic scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Guo Xiaodong [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Zheng Qixin [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Kulbatski, Iris [Division of Cellular and Molecular Biology, Toronto Western Research Institute, University of Toronto, Toronto, Ontario M5T 2S8 (Canada); Yuan Quan [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Yang Shuhua [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Shao Zengwu [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Wang Hong [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Xiao Baojun [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Pan Zhengqi [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China); Tang Shuo [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan 430022 (China)

    2006-09-15

    Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focused on combining gene transfer with tissue engineering techniques. Basic fibroblast growth factor (bFGF) is one of the most prominent osteogenic growth factors that has the potential to accelerate bone healing by promoting the proliferation and differentiation of mesenchymal stem cells (MSCs) and the regeneration of capillary vasculature. However, the short biological half-lives of growth factors may impose severe restraints on their clinical usefulness. Gene-based delivery systems provide a better way of achieving a sustained high concentration of growth factors locally in the defect and delivering a more biologically active product than that achieved by exogenous application of recombinant proteins. The objective of this experimental study was to investigate whether the bFGF gene modified MSCs could enhance the repair of large segmental bone defects. The pcDNA3-bFGF gene transfected MSCs were seeded on biodegradable porous {beta} tricalcium phosphate ({beta}-TCP) ceramics and allografted into the 15 mm critical-sized segmental bone defects in the radius of 18 New Zealand White rabbits. The pcDNA3 vector gene transfected MSCs were taken as the control. The follow-up times were 2, 4, 6, 8, 10 and 12 weeks. Scanning electron microscopic, roentgenographic, histologic and immunohistological studies were used to assess angiogenesis and bone regeneration. In vitro, the proliferation and differentiation of bFGF gene transfected MSCs were more active than that of the control groups. In vivo, significantly more new bone formation accompanied by abundant active capillary regeneration was observed in pores of the ceramics loaded with bFGF gene transfected MSCs, compared with control groups. Transfer of gene encoding bFGF to MSCs increases their osteogenic properties by enhancing capillary regeneration, thus providing a rich blood supply for new bone formation. This new

  20. Bone regeneration with active angiogenesis by basic fibroblast growth factor gene transfected mesenchymal stem cells seeded on porous β-TCP ceramic scaffolds

    International Nuclear Information System (INIS)

    Guo Xiaodong; Zheng Qixin; Kulbatski, Iris; Yuan Quan; Yang Shuhua; Shao Zengwu; Wang Hong; Xiao Baojun; Pan Zhengqi; Tang Shuo

    2006-01-01

    Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focused on combining gene transfer with tissue engineering techniques. Basic fibroblast growth factor (bFGF) is one of the most prominent osteogenic growth factors that has the potential to accelerate bone healing by promoting the proliferation and differentiation of mesenchymal stem cells (MSCs) and the regeneration of capillary vasculature. However, the short biological half-lives of growth factors may impose severe restraints on their clinical usefulness. Gene-based delivery systems provide a better way of achieving a sustained high concentration of growth factors locally in the defect and delivering a more biologically active product than that achieved by exogenous application of recombinant proteins. The objective of this experimental study was to investigate whether the bFGF gene modified MSCs could enhance the repair of large segmental bone defects. The pcDNA3-bFGF gene transfected MSCs were seeded on biodegradable porous β tricalcium phosphate (β-TCP) ceramics and allografted into the 15 mm critical-sized segmental bone defects in the radius of 18 New Zealand White rabbits. The pcDNA3 vector gene transfected MSCs were taken as the control. The follow-up times were 2, 4, 6, 8, 10 and 12 weeks. Scanning electron microscopic, roentgenographic, histologic and immunohistological studies were used to assess angiogenesis and bone regeneration. In vitro, the proliferation and differentiation of bFGF gene transfected MSCs were more active than that of the control groups. In vivo, significantly more new bone formation accompanied by abundant active capillary regeneration was observed in pores of the ceramics loaded with bFGF gene transfected MSCs, compared with control groups. Transfer of gene encoding bFGF to MSCs increases their osteogenic properties by enhancing capillary regeneration, thus providing a rich blood supply for new bone formation. This new b

  1. Transfection mediated by pH-sensitive sugar-based gemini surfactants; potential for in vivo gene therapy applications

    NARCIS (Netherlands)

    Wasungu, Luc; Scarzello, Marco; van Dam, Gooitzen; Molema, Grietje; Wagenaar, Anno; Engberts, Jan B. F. N.; Hoekstra, Dick

    In this study, the in vitro and in vivo transfection capacity of novel pH-sensitive sugar-based gemini surfactants was investigated. In an aqueous environment at physiological pH, these compounds form bilayer vesicles, but they undergo a lamellar-to-micellar phase transition in the endosomal pH

  2. Transfection of Chinese hamster ovary DHFR/sup -/ cells with the gene coding for heat shock protein 70 from drosophila melanogaster

    International Nuclear Information System (INIS)

    Duffy, J.J.; Carper, S.W.; Gerner, E.W.

    1987-01-01

    Chinese hamster ovary DHFR/sup -/ cells (CHO-DHFR/sup -/) were transfected with the plasmid pSV2-dhfr expressing the mouse gene coding for dhfr or with the same plasmid containing the gene coding for the Drosophila melanogaster heat shock protein 70 (hsp70), pSVd-hsp70. Three subcloned cell lines selected for expression of the dhfr gene were shown to contain either the vector sequence (G cells) or varying copies of pSVd-hsp70 (H cells). One line of H cells was shown to contain > 30 copies of the D. melanogaster hsp70 gene and to express the hsp70 RNA at significant levels. No difference between G and H cells was observed in the rate of growth, in the development of thermotolerance, or in the sensitivity of actin microfilament bundles to heat shock. However, H cells containing the transfected hsp70 gene had an altered morphology when compared to the G cells and the parental CHO-DHFR/sup -/ cells being more fibroblastic. The adhesion properties of the H cells was also decreased when compared to the G cells. These results show that insertion of the D. melanogaster gene into CHO cells does not effect growth rates or heat shock responses but may alter cell morphology and adhesion

  3. Repair of full-thickness articular cartilage defects by cultured mesenchymal stem cells transfected with the transforming growth factor {beta}{sub 1} gene

    Energy Technology Data Exchange (ETDEWEB)

    Guo Xiaodong [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Zheng Qixin [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Yang Shuhua [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Shao Zengwu [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Yuan Quan [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Pan Zhengqi [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Tang Shuo [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Liu Kai [Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Quan Daping [Institute of Polymer Science, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275 (China)

    2006-12-15

    Articular cartilage repair remains a clinical and scientific challenge with increasing interest focused on the combined techniques of gene transfer and tissue engineering. Transforming growth factor beta 1 (TGF-{beta}{sub 1}) is a multifunctional molecule that plays a central role in promotion of cartilage repair, and inhibition of inflammatory and alloreactive immune response. Cell mediated gene therapy can allow a sustained expression of TGF-{beta}{sub 1} that may circumvent difficulties associated with growth factor delivery. The objective of this study was to investigate whether TGF-{beta}{sub 1} gene modified mesenchymal stem cells (MSCs) could enhance the repair of full-thickness articular cartilage defects in allogeneic rabbits. The pcDNA{sub 3}-TGF-{beta}{sub 1} gene transfected MSCs were seeded onto biodegradable poly-L-lysine coated polylactide (PLA) biomimetic scaffolds in vitro and allografted into full-thickness articular cartilage defects in 18 New Zealand rabbits. The pcDNA{sub 3} gene transfected MSCs/biomimetic scaffold composites and the cell-free scaffolds were taken as control groups I and II, respectively. The follow-up times were 2, 4, 12 and 24 weeks. Macroscopical, histological and ultrastructural studies were performed. In vitro SEM studies found that abundant cartilaginous matrices were generated and completely covered the interconnected pores of the scaffolds two weeks post-seeding in the experimental groups. In vivo, the quality of regenerated tissue improved over time with hyaline cartilage filling the chondral region and a mixture of trabecular and compact bone filling the subchondral region at 24 weeks post-implantation. Joint repair in the experimental groups was better than that of either control group I or II, with respect to: (1) synthesis of hyaline cartilage specific extracellular matrix at the upper portion of the defect; (2) reconstitution of the subchondral bone at the lower portion of the defect and (3) inhibition of

  4. Repair of full-thickness articular cartilage defects by cultured mesenchymal stem cells transfected with the transforming growth factor β1 gene

    International Nuclear Information System (INIS)

    Guo Xiaodong; Zheng Qixin; Yang Shuhua; Shao Zengwu; Yuan Quan; Pan Zhengqi; Tang Shuo; Liu Kai; Quan Daping

    2006-01-01

    Articular cartilage repair remains a clinical and scientific challenge with increasing interest focused on the combined techniques of gene transfer and tissue engineering. Transforming growth factor beta 1 (TGF-β 1 ) is a multifunctional molecule that plays a central role in promotion of cartilage repair, and inhibition of inflammatory and alloreactive immune response. Cell mediated gene therapy can allow a sustained expression of TGF-β 1 that may circumvent difficulties associated with growth factor delivery. The objective of this study was to investigate whether TGF-β 1 gene modified mesenchymal stem cells (MSCs) could enhance the repair of full-thickness articular cartilage defects in allogeneic rabbits. The pcDNA 3 -TGF-β 1 gene transfected MSCs were seeded onto biodegradable poly-L-lysine coated polylactide (PLA) biomimetic scaffolds in vitro and allografted into full-thickness articular cartilage defects in 18 New Zealand rabbits. The pcDNA 3 gene transfected MSCs/biomimetic scaffold composites and the cell-free scaffolds were taken as control groups I and II, respectively. The follow-up times were 2, 4, 12 and 24 weeks. Macroscopical, histological and ultrastructural studies were performed. In vitro SEM studies found that abundant cartilaginous matrices were generated and completely covered the interconnected pores of the scaffolds two weeks post-seeding in the experimental groups. In vivo, the quality of regenerated tissue improved over time with hyaline cartilage filling the chondral region and a mixture of trabecular and compact bone filling the subchondral region at 24 weeks post-implantation. Joint repair in the experimental groups was better than that of either control group I or II, with respect to: (1) synthesis of hyaline cartilage specific extracellular matrix at the upper portion of the defect; (2) reconstitution of the subchondral bone at the lower portion of the defect and (3) inhibition of inflammatory and alloreactive immune responses. The

  5. Radionuclide reporter gene imaging

    International Nuclear Information System (INIS)

    Min, Jung Joon

    2004-01-01

    Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging biological research. These tools have been validated recently in variety of research models, and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene expression. This article reviews the principles, characteristics, categories and the use of radionuclide reporter gene imaging technologies as they have been used in imaging cell trafficking, imaging gene therapy, imaging endogenous gene expression and imaging molecular interactions. The studies published to date demonstrate that reporter gene imaging technologies will help to accelerate model validation as well as allow for clinical monitoring of human diseases

  6. Radionuclide reporter gene imaging

    Energy Technology Data Exchange (ETDEWEB)

    Min, Jung Joon [School of Medicine, Chonnam National Univ., Gwangju (Korea, Republic of)

    2004-04-01

    Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging biological research. These tools have been validated recently in variety of research models, and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene expression. This article reviews the principles, characteristics, categories and the use of radionuclide reporter gene imaging technologies as they have been used in imaging cell trafficking, imaging gene therapy, imaging endogenous gene expression and imaging molecular interactions. The studies published to date demonstrate that reporter gene imaging technologies will help to accelerate model validation as well as allow for clinical monitoring of human diseases.

  7. Co-transfection of decorin and interleukin-10 modulates pro-fibrotic extracellular matrix gene expression in human tenocyte culture

    Science.gov (United States)

    Abbah, Sunny A.; Thomas, Dilip; Browne, Shane; O'Brien, Timothy; Pandit, Abhay; Zeugolis, Dimitrios I.

    2016-02-01

    Extracellular matrix synthesis and remodelling are driven by increased activity of transforming growth factor beta 1 (TGF-β1). In tendon tissue repair, increased activity of TGF-β1 leads to progressive fibrosis. Decorin (DCN) and interleukin 10 (IL-10) antagonise pathological collagen synthesis by exerting a neutralising effect via downregulation of TGF-β1. Herein, we report that the delivery of DCN and IL-10 transgenes from a collagen hydrogel system supresses the constitutive expression of TGF-β1 and a range of pro-fibrotic extracellular matrix genes.

  8. Advances of reporter gene imaging monitoring stem cell therapy

    International Nuclear Information System (INIS)

    Pei Zhijun; Zhang Yongxue

    2010-01-01

    Stem cell transplantation in the treatment of various tissue damage or degenerative diseases are research hotspots both at home and abroad. However, ignorance of the homing, differentiation and functional expression of the stem cell in vivo influence the further development of stem cell therapy. As an important component of molecular imaging technology, reporter gene imaging dynamically monitors the change of stem cell in vivo via monitoring the expression of transfected reporter gene. This paper briefly describes the latest research progress and the future development trend of the monitoring of reporter gene imaging in stem cell therapy in vivo. (authors)

  9. Imaging reporter gene for monitoring gene therapy

    International Nuclear Information System (INIS)

    Beco, V. de; Baillet, G.; Tamgac, F.; Tofighi, M.; Weinmann, P.; Vergote, J.; Moretti, J.L.; Tamgac, G.

    2002-01-01

    Scintigraphic images can be obtained to document gene function at cellular level. This approach is presented here and the use of a reporter gene to monitor gene therapy is described. Two main ways are presented: either the use of a reporter gene coding for an enzyme the action of which will be monitored by radiolabeled pro-drug, or a cellular receptor gene, the action of which is documented by a radio labeled cognate receptor ligand. (author)

  10. Pathological study on the testis of mice irradiated by γ-rays after transfecting pprI gene by in vivo electroporation

    International Nuclear Information System (INIS)

    Lian Lixia; Chen Tingting; Zhang Yongqin; Wang Xiuzhen; Yang Zhanshan

    2011-01-01

    To investigate the effects of pprI gene from Deinococcus radiodurans transferred by in vivo electroporation on γ-ray injury of mice, the morphological changes of testis in the mice were observed. The pCMV-HA-pprI plasmid containing pprI gene was injected into the muscle of mice. The pprI gene was transfected into the cells by in vivo gene electroporation technology. Then the control group and the transferred pCMV-HA-pprI group were exposed to γ-ray radiation of 6 Gy. The muscle tissue at the site of the injection and the testis tissue were taken on days 1, 7, 14, 28 and 35 after radiation. Then total protein was extracted and used to test the expression of PprI with western blotting technology. The testis specimen prepared by hematoxylin-eosin staining was then examined by light microscopy. The expression of PprI is remarkable on the 1 st day after irradiation to prove that the pprI gene was successfully transfected into the mice. On the 1 st day after irradiation there was no obvious pathological change of the testis tissue of the control group. On the 7th day there was degeneration and necrosis of some spermatogonia and spermatocytes in sections of tubules. On the 14th day, the reduction of spermatogonia was generally marked, and there was considerable reduction in the number of primary spermatocytes associated with atrophy of the seminiferous tubules. On the 28th day there was complete depletion of spermatogenic epithelium when spermatocytes and spermatids had largely disappeared, with no regeneration of spermatogonia and only sertoli cells nuclei remaining along the basement membrane. On the 35th day, spermatogonia were actively regenerating in some of the tubules. Compared with the control group, there was also no significant difference on the 1 st after irradiation in the transgenic animal. On the 7th day the degeneration and necrosis of some spermatogonia and spermatocytes in sections of tubules was less than that of the control group. On the 14th day the

  11. Depletion of 4-hydroxynonenal in hGSTA4-transfected HLE B-3 cells results in profound changes in gene expression

    International Nuclear Information System (INIS)

    Patrick, Brad; Li Jie; Jeyabal, Prince V.S.; Reddy, Prasada M.R.V.; Yang Yusong; Sharma, Rajendra; Sinha, Mala; Luxon, Bruce; Zimniak, Piotr; Awasthi, Sanjay; Awasthi, Yogesh C.

    2005-01-01

    Previously, we have shown that overexpression of 4-hydroxy-2-nonenal (HNE)-detoxifying enzyme glutathione S-transferase A4-4 (hGSTA4-4) in human lens epithelial cells (HLE B-3) leads to pro-carcinogenic phenotypic transformation of these cells [R. Sharma, et al. Eur. J. Biochem. 271 (2004) 1960-1701]. We now demonstrate that hGSTA4-transfection also causes a profound change in the expression of genes involved in cell adhesion, cell cycle control, proliferation, cell growth, and apoptosis, which is consistent with phenotypic changes of the transformed cells. The expression of p53, p21, p16, fibronectin 1, laminin γ1, connexin 43, Fas, integrin α6, TGFα, and c-jun was down-regulated, while the expression of protein kinase C beta II (PKCβII), c-myc, cyclin-dependent kinase 2 (CDK2), and TGFβ was up-regulated in transfected cells. These results demonstrate that HNE serves as a crucial signaling molecule and, by modulating the expression of genes, can influence cellular functions

  12. Mechanistic evaluation of the transfection barriers involved in lipid-mediated gene delivery: Interplay between nanostructure and composition

    Science.gov (United States)

    Pozzi, D.; Marchini, C.; Cardarelli, F.; Salomone, F.; Coppola, S.; Montani, M.; Zabaleta, M. Elexpuru; Digman, M.A.; Gratton, E.; Colapicchioni, V.; Caracciolo, G.

    2014-01-01

    Here we present a quantitative mechanism-based investigation aimed at comparing the cell uptake, intracellular trafficking, endosomal escape and final fate of lipoplexes and lipid–protamine/deoxyribonucleic acid (DNA) (LPD) nanoparticles (NPs) in living Chinese hamster ovary (CHO) cells. As a model, two lipid formulations were used for comparison. The first formulation is made of the cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and the zwitterionic lipid dioleoylphosphocholine (DOPC), while the second mixture is made of the cationic 3β-[N-(N,N-dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol) and the zwitterionic helper lipid dioleoylphosphatidylethanolamine (DOPE). Our findings indicate that lipoplexes are efficiently taken up through fluid-phase macropinocytosis, while a less efficient uptake of LPD NPs occurs through a combination of both macropinocytosis and clathrin-dependent pathways. Inside the cell, both lipoplexes and LPD NPs are actively transported towards the cell nucleus, as quantitatively addressed by spatio-temporal image correlation spectroscopy (STICS). For each lipid formulation, LPD NPs escape from endosomes more efficiently than lipoplexes. When cells were treated with DOTAP–DOPC-containing systems the majority of the DNA was trapped in the lysosome compartment, suggesting that extensive lysosomal degradation was the rate-limiting factors in DOTAP–DOPC-mediated transfection. On the other side, escape from endosomes is large for DC-Chol–DOPE-containing systems most likely due to DOPE and cholesterol-like molecules, which are able to destabilize the endosomal membrane. The lipid-dependent and structure-dependent enhancement of transfection activity suggests that DNA is delivered to the nucleus synergistically: the process requires both the membrane-fusogenic activity of the nanocarrier envelope and the employment of lipid species with intrinsic endosomal rupture ability. PMID:24296066

  13. In vitro studies of magnetically enhanced transfection in COS-7 cells

    International Nuclear Information System (INIS)

    Ang, D.; Tay, C.Y.; Tan, L.P.; Preiser, P.R.; Ramanujan, R.V.

    2011-01-01

    In the magnetically enhanced gene delivery technique, DNA complexed with polymer coated aggregated magnetic nanoparticles (AMNPs) is used for effecting transfection. The aim of this study is to examine the relationship between transfection efficiency and the physical characteristics of the polymer coated AMNPs. In vitro studies of transfection efficiency in COS-7 cells were carried out using pEGFP-N1 and pMIR-REPORT complexed polyethylenimine (PEI) coated iron oxide magnetic nanoparticles. PEI coated AMNPs (PEI-AMNPs) with average individual particle diameters in the range of 8 nm to 30 nm were studied and characterized by transmission electron microscopy, vibrating sample magnetometry, X-ray diffractometry, thermal gravimetric analysis and photon correlation spectroscopy methods. PEI-A8MNP and PEI-A30MNP yielded higher transfection efficiency compared to commercial polyMAG particles as well as PEI of equivalent molar ratio of nitrogen/phosphorous (N/P ratio). The transfection efficiency was related to the physical characteristics of the PEI-AMNPs and its complexes: transfection efficiency was strongly positively correlated with saturation magnetization (Ms) and susceptibility (χ), strongly negatively correlated with N/P ratio, moderately positively correlated to zeta potential and moderately negatively correlated to hydrodynamic diameter of the complex. PEI-A8MNP and PEI-A30MNP possessing higher Ms, χ, lower N/P ratio and smaller complex size exhibited higher transfection efficiency compared to PEI-A16MNP which have weaker magnetic properties, higher N/P ratio and larger complex size. We have demonstrated that optimization of the physical properties of PEI-AMNPs is needed to maximize transfection efficiency. - Research highlights: →The transfection efficiency in magnetically enhanced gene delivery was studied. →Transfection efficiency was strongly positively correlated to magnetic properties. →Transfection efficiency was strongly negatively correlated with

  14. Serum as a modulator of lipoplex-mediated gene transfection : dependence of amphiphile, cell type and complex stability

    NARCIS (Netherlands)

    Audouy, S; Molema, G; de Leij, L; Hoekstra, D

    2000-01-01

    Background Cationic liposomes belong to the family of non-viral vectors for gene delivery. Despite several drawbacks, such as low efficiency compared to viruses and inactivation by serum, cationic liposomes remain a promising tool for gene therapy. Therefore further investigation of the mechanism of

  15. Combination of HIF-1α gene transfection and HIF-1-activated bone marrow-derived angiogenic cell infusion improves burn wound healing in aged mice.

    Science.gov (United States)

    Du, J; Liu, L; Lay, F; Wang, Q; Dou, C; Zhang, X; Hosseini, S M; Simon, A; Rees, D J; Ahmed, A K; Sebastian, R; Sarkar, K; Milner, S; Marti, G P; Semenza, G L; Harmon, J W

    2013-11-01

    Impaired burn wound healing in the elderly represents a major clinical problem. Hypoxia-inducible factor-1 (HIF-1) is a transcriptional activator that orchestrates the cellular response to hypoxia. Its actions in dermal wounds promote angiogenesis and improve healing. In a murine burn wound model, aged mice had impaired wound healing associated with reduced levels of HIF-1. When gene therapy with HIF-1 alone did not correct these deficits, we explored the potential benefit of HIF-1 gene therapy combined with the intravenous infusion of bone marrow-derived angiogenic cells (BMDACs) cultured with dimethyloxalylglycine (DMOG). DMOG is known to reduce oxidative degradation of HIF-1. The mice treated with a plasmid DNA construct expressing a stabilized mutant form of HIF-1α (CA5-HIF-1α)+BMDACs had more rapid wound closure. By day 17, there were more mice with completely closed wounds in the treated group (χ(2), P=0.05). The dermal blood flow measured by laser Doppler showed significantly increased wound perfusion on day 11. Homing of BMDACs to the burn wound was dramatically enhanced by CA5-HIF-1α gene therapy. HIF-1α mRNA expression in the burn wound was increased after transfection with CA5-HIF-1α plasmid. Our findings offer insight into the pathophysiology of burns in the elderly and point to potential targets for developing new therapeutic strategies.

  16. Pentablock copolymers of pluronic F127 and modified poly(2-dimethyl aminoethyl methacrylate for internalization mechanism and gene transfection studies

    Directory of Open Access Journals (Sweden)

    Huang SJ

    2013-05-01

    Full Text Available Shih-Jer Huang,1 Tzu-Pin Wang,1 Sheng-I Lue,2 Li-Fang Wang11Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan; 2Department of Physiology, Kaohsiung Medical University, Kaohsiung, TaiwanAbstract: Cationic polymers are one of the major nonviral gene delivery vectors investigated in the past decade. In this study, we synthesized several cationic copolymers using atom transfer radical polymerization (ATRP for gene delivery vectors: pluronic F127-poly(dimethylaminoethyl methacrylate (PF127-pDMAEMA, pluronic F127-poly (dimethylaminoethyl methacrylate-tert-butyl acrylate (PF127-p(DMAEMA-tBA, and pluronic F127-poly(dimethylaminoethyl methacrylate-acrylic acid (PF127-p(DMAEMA-AA. The copolymers showed high buffering capacity and efficiently complexed with plasmid deoxyribonucleic acid (pDNA to form nanoparticles 80–180 nm in diameter and with positive zeta potentials. In the absence of 10% fetal bovine serum, PF127-p(DMAEMA-AA showed the highest gene expression and the lowest cytotoxicity in 293T cells. After acrylic acid groups had been linked with a fluorescent dye, the confocal laser scanning microscopic image showed that PF127-p(DMAEMA-AA/pDNA could efficiently enter the cells. Both clathrin-mediated and caveolae-mediated endocytosis mechanisms were involved. Our results showed that PF127-p(DMAEMA-AA has great potential to be a gene delivery vector.Keywords: nonviral vector, pluronic F127, dimethylaminoethyl methacrylate, copolymer, atom transfer radical polymerization

  17. Nano-biolistics: a method of biolistic transfection of cells and tissues using a gene gun with novel nanometer-sized projectiles

    Directory of Open Access Journals (Sweden)

    Lummis Sarah CR

    2011-06-01

    Full Text Available Abstract Background Biolistic transfection is proving an increasingly popular method of incorporating DNA or RNA into cells that are difficult to transfect using traditional methods. The technique routinely uses 'microparticles', which are ~1 μm diameter projectiles, fired into tissues using pressurised gas. These microparticles are efficient at delivering DNA into cells, but cannot efficiently transfect small cells and may cause significant tissue damage, thus limiting their potential usefulness. Here we describe the use of 40 nm diameter projectiles - nanoparticles - in biolistic transfections to determine if they are a suitable alternative to microparticles. Results Examination of transfection efficiencies in HEK293 cells, using a range of conditions including different DNA concentrations and different preparation procedures, reveals similar behaviour of microparticles and nanoparticles. The use of nanoparticles, however, resulted in ~30% fewer damaged HEK293 cells following transfection. Biolistic transfection of mouse ear tissue revealed similar depth penetration for the two types of particles, and also showed that 20% in microparticle-transfected samples. Visualising details of small cellular structures was also considerably enhanced when using nanoparticles. Conclusions We conclude that nanoparticles are as efficient for biolistic transfection as microparticles, and are more appropriate for use in small cells, when examining cellular structures and/or where tissue damage is a problem.

  18. Processing of high-molecular-weight form adrenocorticotropin in human adrenocorticotropin-secreting tumor cell line (DMS-79) after transfection of prohormone convertase 1/3 gene.

    Science.gov (United States)

    Tateno, T; Kato, M; Tani, Y; Yoshimoto, T; Oki, Y; Hirata, Y

    2010-02-01

    Ectopic ACTH-producing tumors preferentially secrete biologically inactive ACTH precursors and ACTH-related fragments. DMS-79 is known to secrete unprocessed high-molecular-weight (HMW) form ACTH. To determine whether prohormone convertase (PC) 1/3 is involved in the abnormal processing of proopiomelanocortin (POMC), we studied whether PC1/3 and 2 genes are expressed in DMS-79, and whether overexpression of PC1/3 gene affects POMC processing pattern. Steady-state mRNA levels of PC1/3 and 2 were determined by real-time RT-PCR. Molecular weights of ACTH-related peptides were determined by chromatographical analyses coupled with ACTH and beta-endorphin (beta-END) radioimmunoassays. PC1/3 gene was transfected into DMS-79 by retrovirus transduction using pMX-IP vector encoding PC1/3 cDNA. The steady-state mRNA levels of PC1/3 and 2 in DMS-79 were lower than those in ACTH-secreting and nonfunctioning pituitary tumors. DMS-79 predominantly secreted HMW form with both ACTH and beta-END immunoreactivities by size-exclusion chromatography. After purification by immunoaffinity chromatography with anti-ACTH antibody, the apparent molecular weight of HMW form ACTH was estimated to be 16 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis with silver staining. After retroviral transfection of PC1/3 cDNA into DMS-79 and puromycin selection, PC1/3 stably-expressing cell line (DMS-79T) secreted two immunoreactive ACTH components, a major one coeluting with ACTH(1-39) and a minor one as a HMW form as well as two beta- END immunoreactive components coeluting with beta-lipotropic hormone and beta-END, respectively. Thus, we have established PC1/3 stably-expressing cell line (DMS-79T) capable of proteolytically processing ACTH precursor molecule(s) into mature ACTH and beta-END.

  19. Transfection of Platyhelminthes

    Directory of Open Access Journals (Sweden)

    Bárbara Moguel

    2015-01-01

    Full Text Available Flatworms are one of the most diverse groups within Lophotrochozoa with more than 20,000 known species, distributed worldwide in different ecosystems, from the free-living organisms in the seas and lakes to highly specialized parasites living in a variety of hosts, including humans. Several infections caused by flatworms are considered major neglected diseases affecting countries in the Americas, Asia, and Africa. For several decades, a particular interest on free-living flatworms was due to their ability to regenerate considerable portions of the body, implying the presence of germ cells that could be important for medicine. The relevance of reverse genetics for this group is clear; understanding the phenotypic characteristics of specific genes will shed light on developmental traits of free-living and parasite worms. The genetic manipulation of flatworms will allow learning more about the mechanisms for tissue regeneration, designing new and more effective anthelmintic drugs, and explaining the host-parasite molecular crosstalk so far partially inaccessible for experimentation. In this review, availability of transfection techniques is analyzed across flatworms, from the initial transient achievements to the stable manipulations now developed for free-living and parasite species.

  20. mRNA transfection of mouse and human neural stem cell cultures.

    Directory of Open Access Journals (Sweden)

    Samuel McLenachan

    Full Text Available The use of synthetic mRNA as an alternative gene delivery vector to traditional DNA-based constructs provides an effective method for inducing transient gene expression in cell cultures without genetic modification. Delivery of mRNA has been proposed as a safer alternative to viral vectors in the induction of pluripotent cells for regenerative therapies. Although mRNA transfection of fibroblasts, dendritic and embryonic stem cells has been described, mRNA delivery to neurosphere cultures has not been previously reported. Here we sought to establish an efficient method for delivering mRNA to primary neurosphere cultures. Neurospheres derived from the subventricular zone of adult mice or from human embryonic stem cells were transfected with EGFP mRNA by lipofection and electroporation. Transfection efficiency and expression levels were monitored by flow cytometry. Cell survival following transfection was examined using live cell counting and the MTT assay. Both lipofection and electroporation provided high efficiency transfection of neurospheres. In comparison with lipofection, electroporation resulted in increased transfection efficiencies, but lower expression per cell and shorter durations of expression. Additional rounds of lipofection renewed EGFP expression in neurospheres, suggesting this method may be suitable for reprogramming applications. In summary, we have developed a protocol for achieving high efficiency transfection rates in mouse and human neurosphere cell culture that can be applied for future studies of gene function studies in neural stem cells, such as defining efficient differentiation protocols for glial and neuronal linages.

  1. mRNA Transfection of Mouse and Human Neural Stem Cell Cultures

    Science.gov (United States)

    McLenachan, Samuel; Zhang, Dan; Palomo, Ana Belén Alvarez; Edel, Michael J.; Chen, Fred K.

    2013-01-01

    The use of synthetic mRNA as an alternative gene delivery vector to traditional DNA-based constructs provides an effective method for inducing transient gene expression in cell cultures without genetic modification. Delivery of mRNA has been proposed as a safer alternative to viral vectors in the induction of pluripotent cells for regenerative therapies. Although mRNA transfection of fibroblasts, dendritic and embryonic stem cells has been described, mRNA delivery to neurosphere cultures has not been previously reported. Here we sought to establish an efficient method for delivering mRNA to primary neurosphere cultures. Neurospheres derived from the subventricular zone of adult mice or from human embryonic stem cells were transfected with EGFP mRNA by lipofection and electroporation. Transfection efficiency and expression levels were monitored by flow cytometry. Cell survival following transfection was examined using live cell counting and the MTT assay. Both lipofection and electroporation provided high efficiency transfection of neurospheres. In comparison with lipofection, electroporation resulted in increased transfection efficiencies, but lower expression per cell and shorter durations of expression. Additional rounds of lipofection renewed EGFP expression in neurospheres, suggesting this method may be suitable for reprogramming applications. In summary, we have developed a protocol for achieving high efficiency transfection rates in mouse and human neurosphere cell culture that can be applied for future studies of gene function studies in neural stem cells, such as defining efficient differentiation protocols for glial and neuronal linages. PMID:24386231

  2. mRNA transfection of mouse and human neural stem cell cultures.

    Science.gov (United States)

    McLenachan, Samuel; Zhang, Dan; Palomo, Ana Belén Alvarez; Edel, Michael J; Chen, Fred K

    2013-01-01

    The use of synthetic mRNA as an alternative gene delivery vector to traditional DNA-based constructs provides an effective method for inducing transient gene expression in cell cultures without genetic modification. Delivery of mRNA has been proposed as a safer alternative to viral vectors in the induction of pluripotent cells for regenerative therapies. Although mRNA transfection of fibroblasts, dendritic and embryonic stem cells has been described, mRNA delivery to neurosphere cultures has not been previously reported. Here we sought to establish an efficient method for delivering mRNA to primary neurosphere cultures. Neurospheres derived from the subventricular zone of adult mice or from human embryonic stem cells were transfected with EGFP mRNA by lipofection and electroporation. Transfection efficiency and expression levels were monitored by flow cytometry. Cell survival following transfection was examined using live cell counting and the MTT assay. Both lipofection and electroporation provided high efficiency transfection of neurospheres. In comparison with lipofection, electroporation resulted in increased transfection efficiencies, but lower expression per cell and shorter durations of expression. Additional rounds of lipofection renewed EGFP expression in neurospheres, suggesting this method may be suitable for reprogramming applications. In summary, we have developed a protocol for achieving high efficiency transfection rates in mouse and human neurosphere cell culture that can be applied for future studies of gene function studies in neural stem cells, such as defining efficient differentiation protocols for glial and neuronal linages.

  3. A simple protocol for preparation of a liposomal vesicle with encapsulated plasmid DNA that mediate high accumulation and reporter gene activity in tumor tissue

    DEFF Research Database (Denmark)

    Gjetting, Torben; Andresen, Thomas Lars; Christensen, Camilla Laulund

    2011-01-01

    The systemic delivery of gene therapeutics by non-viral methods has proven difficult. Transfection systems that are performing well in vitro have been reported to have disadvantageous properties such as rapid clearance and short circulation time often resulting in poor transfection efficiency whe...

  4. A simple protocol for preparation of a liposomal vesicle with encapsulated plasmid DNA that mediate high accumulation and reporter gene activity in tumor tissue

    DEFF Research Database (Denmark)

    Gjetting, Torben; Andresen, Thomas Lars; Christensen, Camilla Laulund

    2011-01-01

    The systemic delivery of gene therapeutics by non-viral methods has proven dif¿cult. Transfection systems that are performing well in vitro have been reported to have disadvantageous properties such as rapid clearance and short circulation time often resulting in poor transfection ef¿ciency when ...

  5. Preparation, characterization, and efficient transfection of cationic liposomes and nanomagnetic cationic liposomes

    Directory of Open Access Journals (Sweden)

    Samadikhah HR

    2011-10-01

    Full Text Available Hamid Reza Samadikhah1,*, Asia Majidi2,*, Maryam Nikkhah2, Saman Hosseinkhani11Department of Biochemistry, 2Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran *These authors contributed equally to this work Purpose: Cationic liposomes (CLs are composed of phospholipid bilayers. One of the most important applications of these particles is in drug and gene delivery. However, using CLs to deliver therapeutic nucleic acids and drugs to target organs has some problems, including low transfection efficiency in vivo. The aim of this study was to develop novel CLs containing magnetite to overcome the deficiencies. Patients and methods: CLs and magnetic cationic liposomes (MCLs were prepared using the freeze-dried empty liposome method. Luciferase-harboring vectors (pGL3 were transferred into liposomes and the transfection efficiencies were determined by luciferase assay. Firefly luciferase is one of most popular reporter genes often used to measure the efficiency of gene transfer in vivo and in vitro. Different formulations of liposomes have been used for delivery of different kinds of gene reporters. Lipoplex (liposome–plasmid DNA complexes formation was monitored by gel retardation assay. Size and charge of lipoplexes were determined using particle size analysis. Chinese hamster ovary cells were transfected by lipoplexes (liposome-pGL3; transfection efficiency and gene expression level was evaluated by luciferase assay. Results: High transfection efficiency of plasmid by CLs and novel nanomagnetic CLs was achieved. Moreover, lipoplexes showed less cytotoxicity than polyethyleneimine and Lipofectamine™. Conclusion: Novel liposome compositions (1,2-dipalmitoyl-sn-glycero-3-phosphocholine [DPPC]/dioctadecyldimethylammonium bromide [DOAB] and DPPC/cholesterol/DOAB with high transfection efficiency can be useful in gene delivery in vitro. MCLs can also be used for targeted gene delivery, due to

  6. In vitro and in vivo effects of polyethylene glycol (PEG)-modified lipid in DOTAP/cholesterol-mediated gene transfection

    DEFF Research Database (Denmark)

    Gjetting, Torben; Arildsen, Nicolai Skovbjerg; Christensen, Camilla Laulund

    2010-01-01

    DOTAP/cholesterol-based lipoplexes are successfully used for delivery of plasmid DNA in vivo especially to the lungs, although low systemic stability and circulation have been reported. To achieve the aim of discovering the best method for systemic delivery of DNA to disseminated tumors we evalua...... evaluated the potential of formulating DOTAP/cholesterol lipoplexes with a polyethylene glycol (PEG)-modified lipid, giving the benefit of the shielding and stabilizing properties of PEG in the bloodstream....

  7. Toward establishing model organisms for marine protists: Successful transfection protocols for Parabodo caudatus (Kinetoplastida: Excavata).

    Science.gov (United States)

    Gomaa, Fatma; Garcia, Paulo A; Delaney, Jennifer; Girguis, Peter R; Buie, Cullen R; Edgcomb, Virginia P

    2017-09-01

    We developed protocols for, and demonstrated successful transfection of, the free-living kinetoplastid flagellate Parabodo caudatus with three plasmids carrying a fluorescence reporter gene (pEF-GFP with the EF1 alpha promoter, pUB-GFP with Ubiquitin C promoter, and pEYFP-Mitotrap with CMV promoter). We evaluated three electroporation approaches: (1) a square-wave electroporator designed for eukaryotes, (2) a novel microfluidic transfection system employing hydrodynamically-controlled electric field waveforms, and (3) a traditional exponential decay electroporator. We found the microfluidic device provides a simple and efficient platform to quickly test a wide range of electric field parameters to find the optimal set of conditions for electroporation of target species. It also allows for processing large sample volumes (>10 ml) within minutes, increasing throughput 100 times over cuvettes. Fluorescence signal from the reporter gene was detected a few hours after transfection and persisted for 3 days in cells transfected by pEF-GFP and pUB-GFP plasmids and for at least 5 days post-transfection for cells transfected with pEYFP-Mitotrap. Expression of the reporter genes (GFP and YFP) was also confirmed using reverse transcription-PCR (RT-PCR). This work opens the door for further efforts with this taxon and close relatives toward establishing model systems for genome editing. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  8. Differential adenoassociated virus vector-driven expression of a neuropeptide Y gene in primary rat brain astroglial cultures after transfection with Sendai virosomes versus Lipofectin.

    Science.gov (United States)

    de Fiebre, C M; Wu, P; Notabartolo, D; Millard, W J; Meyer, E M

    1994-06-01

    The ability of Sendai virosomes or Lipofectin to introduce an AAV vector into primary rat brain astroglial cultures was characterized. The pJDT95npy vector was constructed by inserting rat NPY cDNA downstream from the indigenous AAV p5, p19 and p40 promoters in pJDT95. Lipofectin-mediated transfection with pJDT95npy (10 micrograms) resulted in pronounced expression of several NPY mRNA species: p5-driven (3.3 kb), p19-driven (2.7 kb) and p40-driven (0.6, 0.8, 1.1, and 1.8 kb). Exposure to virosomally encapsulated pJDT95npy (50 or 100 ng) resulted in transient expression of some p40-driven mRNA species (0.8 and 1.8 kb). Neither method produced astroglia cells which synthesized mature NPY immunoreactivity. This demonstrates that an AAV-derived vector can drive gene expression in astroglia, that Sendai virosomes can infuse vectors into astroglia, but that the amount of DNA infused in this manner may limit long term expression.

  9. Synthesis and NMR characterization of dendrimers based on 2, 2-bis-(hydroxymethyl-propanoic acid (bis-HMPA containing peripheral amino acid residues for gene transfection

    Directory of Open Access Journals (Sweden)

    Silvana Alfei

    2017-08-01

    Full Text Available Dendrimers, the emerging man made, highly branched, star-shaped macromolecules with nanometer-scale dimensions are well known for their well defined and high controlled architecture, their versatility and high functionality and are of eminent interest in nanomedical applications such as drug delivery, gene transfection, and imaging. In this paper, versatile protocols for the synthesis of polyester-based, hydrolysable, polycationic dendrimers have been setup. A fourth generation dendrimer equipped with 48 peripheral hydroxyl groups was prepared from 2,2-bis(hydroxymethylpropanoic acid and was used for grafting BOC-amino acids or as “hypercores” on which dendrons functionalized with BOC-amino acids were attached. A library of 15 polycationic homo- and hetero-dendrimers in the form of hydrochloride was obtained. Their structures and composition were confirmed by NMR analysis and by experimental molecular weight computed by volumetric titration. Their buffer capacity and results obtained from cytotoxicity assays and tests of binding with both pDNA and siRNA were very satisfactory.

  10. Transfection of cultured cells of the cotton boll weevil, Anthonomus grandis, with a heat-shock-promoter-chloramphenicol-acetyltransferase construct.

    Science.gov (United States)

    Stiles, B; Heilmann, J; Sparks, R B; Santoso, A; Leopold, R A

    1992-01-01

    Expression of heat shock proteins (hsp) in the BRL-AG-3C cell line from the cotton boll weevil was examined. It was determined that the maximal expression of endogenous hsp occurred at 41 degrees C. Various transfection methods were then compared using this cell line in conjunction with a transiently expressed bacterial gene marker (chloramphenicol acetyltransferase) which was under the control of the Drosophila hsp 70 gene promoter. The cationic lipid preparation Lipofectin was found to be very efficient at transfecting the boll weevil cells. Polylysine and 20-hydroxyecdysone-conjugated polylysine were moderately effective, whereas polybrene and electroporation, under the conditions reported herein, were ineffective at transfecting this cell line.

  11. A small scale cell culture system to analyze mechanobiology using reporter gene constructs and polyurethane dishes

    DEFF Research Database (Denmark)

    Seefried, Lothar; Mueller-Deubert, Sigrid; Wentzer, Thomas Schwarz

    2010-01-01

    of mechanotransduction and its crosstalk with biochemically induced signal transduction, AP1 and SP1 luciferase reporter gene constructs were cloned and transfected into various cell lines and primary cells. A newly developed bioreactor and small-scale 24-well polyurethane dishes were used to apply cyclic stretching...

  12. Design, synthesis, and in vitro transfection biology of novel tocopherol based monocationic lipids: a structure-activity investigation.

    Science.gov (United States)

    Kedika, Bhavani; Patri, Srilakshmi V

    2011-01-27

    Herein, we report on the design, synthesis, and in vitro gene delivery efficacies of five novel tocopherol based cationic lipids (1-5) in transfecting CHO, B16F10, A-549, and HepG2 cells. The in vitro gene transfer efficiencies of lipids (1-5) were evaluated by both β-galactosidase reporter gene expression and inverted fluorescent microscopic experiments. The results of the present structure-activity investigation convincingly demonstrate that the tocopherol based lipid with three hydroxyl groups in its headgroup region showed 4-fold better transfection efficiency than the commercial formulation. The results also demonstrate that these tocopherol based lipids may be targeted to liver. Transfection efficiency of all the relevant lipids was maintained even when the serum was present during the transfection conditions. The results indicated that the designed systems are quite capable of transferring the DNA into all four types of cells studied with low or no toxicity.

  13. Gene delivery using calcium phosphate nanoparticles: Optimization of the transfection process and the effects of citrate and poly(l-lysine) as additives.

    Science.gov (United States)

    Khan, Mohammed A; Wu, Victoria M; Ghosh, Shreya; Uskoković, Vuk

    2016-06-01

    Despite the long history of nanoparticulate calcium phosphate (CaP) as a non-viral transfection agent, there has been limited success in attempts to optimize its properties for transfection comparable in efficiency to that of viral vectors. Here we focus on the optimization of: (a) CaP nanoparticle precipitation conditions, predominantly supersaturation and Ca/P molar ratios; (b) transfection conditions, mainly the concentrations of the carrier and plasmid DNA; (c) the presence of surface additives, including citrate anion and cationic poly(l-lysine) (PLL). CaP nanoparticles significantly improved transfection with plasmid DNA encoding enhanced green fluorescent protein (eGFP) in pre-osteoblastic MC3T3-E1 cells compared to a commercial non-viral carrier. At the same time they elicited significantly lesser cytotoxicity than the commercial carrier. Plasmid DNA acted as a nucleation promoter, decreasing the nucleation lag time of metastable CaP solutions and leading to a higher rate of nucleation and a lower size of the precipitated particles. The degree of supersaturation (DS) of 15 was found to be more optimal for transfection than that of 12.5 or 17.5 and higher. Because CaP particles precipitated at DS 15 were spherical, while DS 17.5 and 21 yielded acicular particles, it was concluded that spherical particle morphologies were more conducive to transfection than the anisotropic ones. Even though the yield at DS 15 was 10 and 100 times lower than that at DS 17.5 and 21, respectively, transfection rates were higher using CaP nanoparticle colloids prepared at DS 15 than using those made at higher or lower DS, indicating that the right particle morphology can outweigh the difference in the amount of the carrier, even when this difference is close to 100×. In contrast to the commercial carrier, the concentration of CaP-pDNA delivered to the cells was directly proportional to the transfection rate. Osteosarcoma K7M2 cells were four times more easily transfectable with

  14. Improved biolistic transfection of hair cells.

    Directory of Open Access Journals (Sweden)

    Hongyu Zhao

    Full Text Available Transient transfection of hair cells has proven challenging. Here we describe modifications to the Bio-Rad Helios Gene Gun that, along with an optimized protocol, improve transfection of bullfrog, chick, and mouse hair cells. The increased penetrating power afforded by our method allowed us to transfect mouse hair cells from the basal side, through the basilar membrane; this configuration protects hair bundles from damage during the procedure. We characterized the efficiency of transfection of mouse hair cells with fluorescently-tagged actin fusion protein using both the optimized procedure and a published procedure; while the efficiency of the two methods was similar, the morphology of transfected hair cells was improved with the new procedure. In addition, using the improved method, we were able to transfect hair cells in the bullfrog sacculus and chick cochlea for the first time. We used fluorescent-protein fusions of harmonin b (USH1C and PMCA2 (ATP2B2; plasma-membrane Ca(2+-ATPase isoform 2 to examine protein distribution in hair cells. While PMCA2-EGFP localization was similar to endogenous PMCA2 detected with antibodies, high levels of harmonin-EGFP were found at stereocilia tapers in bullfrog and chick, but not mouse; by contrast, harmonin-EGFP was concentrated in stereocilia tips in mouse hair cells.

  15. Aspects of nonviral gene therapy: correlation of molecular parameters with lipoplex structure and transfection efficacy in pyridinium-based cationic lipids.

    Science.gov (United States)

    Parvizi, Paria; Jubeli, Emile; Raju, Liji; Khalique, Nada Abdul; Almeer, Ahmed; Allam, Hebatalla; Manaa, Maryem Al; Larsen, Helge; Nicholson, David; Pungente, Michael D; Fyles, Thomas M

    2014-01-30

    This study seeks correlations between the molecular structures of cationic and neutral lipids, the lipid phase behavior of the mixed-lipid lipoplexes they form with plasmid DNA, and the transfection efficacy of the lipoplexes. Synthetic cationic pyridinium lipids were co-formulated (1:1) with the cationic lipid 1,2-dimyristoyl-sn-glycero-3-ethylphosphocholine (EPC), and these lipids were co-formulated (3:2) with the neutral lipids 1,2-dioleoyl-sn-glycero-3-phosphatidylethanolamine (DOPE) or cholesterol. All lipoplex formulations exhibited plasmid DNA binding and a level of protection from DNase I degradation. Composition-dependent transfection (beta-galactosidase and GFP) and cytotoxicity was observed in Chinese hamster ovarian-K1 cells. The most active formulations containing the pyridinium lipids were less cytotoxic but of comparable activity to a Lipofectamine 2000™ control. Molecular structure parameters and partition coefficients were calculated for all lipids using fragment additive methods. The derived shape parameter values correctly correlated with observed hexagonal lipid phase behavior of lipoplexes as derived from small-angle X-ray scattering experiments. A transfection index applicable to hexagonal phase lipoplexes derived from calculated parameters of the lipid mixture (partition coefficient, shape parameter, lipoplex packing) produced a direct correlation with transfection efficiency. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Recombinant carcinoembryonic antigen as a reporter gene for molecular imaging

    International Nuclear Information System (INIS)

    Kenanova, Vania; Barat, Bhaswati; Olafsen, Tove; Chatziioannou, Arion; Herschman, Harvey R.; Wu, Anna M.; Braun, Jonathan

    2009-01-01

    Reporter genes can provide a way of noninvasively assessing gene activity in vivo. However, current reporter gene strategies may be limited by the immunogenicity of foreign reporter proteins, endogenous expression, or unwanted biological activity. We have developed a reporter gene based on carcinoembryonic antigen (CEA), a human protein with limited normal tissue expression. To construct a CEA reporter gene for PET, a CEA minigene (N-A3) was fused to the extracellular and transmembrane domains of the human FcγRIIb receptor. The NA3-FcγRIIb recombinant gene, driven by a CMV promoter, was transfected in Jurkat (human T cell leukemia) cells. Expression was analyzed by flow cytometry, immunohistochemistry (IHC), and microPET imaging. Flow cytometry identified Jurkat clones stably expressing NA3-FcγRIIb at low, medium, and high levels. High and medium NA3-FcγRIIb expression could also be detected by Western blot. Reporter gene positive and negative Jurkat cells were used to establish xenografts in athymic mice. IHC showed staining of the tumor with high reporter gene expression; medium and low N-A3 expression was not detected. MicroPET imaging, using an anti-CEA 124 I-labeled single-chain Fv-Fc antibody fragment, demonstrated that only high N-A3 expression could be detected. Specific accumulation of activity was visualized at the N-A3 positive tumor as early as 4 h. MicroPET image quantitation showed tumor activity of 1.8 ± 0.2, 15.2 ± 1.3, and 4.6 ± 1.2 percent injected dose per gram (%ID/g) at 4, 20, and 48 h, respectively. Biodistribution at 48 h demonstrated tumor uptake of 4.8 ± 0.8%ID/g. The CEA N-A3 minigene has the potential to be used as a reporter gene for imaging cells in vivo. (orig.)

  17. Introduction of optical reporter gene into cancer and immune cells using lentiviral vector

    International Nuclear Information System (INIS)

    Min, Jung Joon; Le, Uyenchi N.; Moon, Sung Min; Heo, Young Jun; Song, Ho Chun; Bom, Hee Seung; Kim, Yeon Soo

    2004-01-01

    For some applications such as gene therapy or reporter gene imaging, a gene has to be introduced into the organism of interest. Adenoviral vectors are capable of transducing both replicating and non-dividing cells. The adenoviral vectors do not integrate their DNA into host DNA, but do lead to an immune response. Lentiviruses belong to the retrovirus family and are capable of infecting both dividing and non-dividing cells. The human immunodeficiency virus (HIV) is an example of a lentavirus. A disabled HIV virus has been developed and could be used for in vivo gene delivery. A portion of the viral genome which encodes for accessory proteins canbe deleted without affecting production of the vector and efficiency of infection. Lentiviral delivery into various rodent tissues shows sustained expression of the transgene of up to six months. Furthermore, there seems to be little or no immune response with these vectors. These lentiviral vectors hold significant promise for in vivo gene delivery. We constructed lentiviral vector encoding firefly luciferase (Fluc) and eGFP. Fluc-eGFP fusion gene was inserted into multiple cloning sites of pLentiM1.3 vector. Reporter gene (Fluc-eGFP) was designed to be driven by murine CMV promoter with enhanced efficacy of transgene expression as compared to human CMV promoter. We transfected pLenti1.3-Fluc into human cervix cancer cell line (HeLa) and murine T lymphocytes. We also constructed adenovirus encoding Fluc and transfected to HeLa and T cells. This LentiM1.3-Fluc was transfected into HeLa cells and murine T lymphocytes in vitro, showing consistent expression of eGFP under the fluorescence microscopy from the 2nd day of transfection. Firefly luciferase reporter gene was not expressed in immune cells when it is mediated by adenovirus. Lentivirus was validated as a useful vector for both immune and cancer cells

  18. Lipid-based Transfection Reagents Exhibit Cryo-induced Increase in Transfection Efficiency

    Directory of Open Access Journals (Sweden)

    Helena Sork

    2016-01-01

    Full Text Available The advantages of lipid-based transfection reagents have permitted their widespread use in molecular biology and gene therapy. This study outlines the effect of cryo-manipulation of a cationic lipid-based formulation, Lipofectamine 2000, which, after being frozen and thawed, showed orders of magnitude higher plasmid delivery efficiency throughout eight different cell lines, without compromising cell viability. Increased transfection efficiency with the freeze-thawed reagent was also seen with 2'-O-methyl phosphorothioate oligonucleotide delivery and in a splice-correction assay. Most importantly, a log-scale improvement in gene delivery using the freeze-thawed reagent was seen in vivo. Using three different methods, we detected considerable differences in the polydispersity of the different nucleic acid complexes as well as observed a clear difference in their surface spreading and sedimentation, with the freeze-thawed ones displaying substantially higher rate of dispersion and deposition on the glass surface. This hitherto overlooked elevated potency of the freeze-thawed reagent facilitates the targeting of hard-to-transfect cells, accomplishes higher transfection rates, and decreases the overall amount of reagent needed for delivery. Additionally, as we also saw a slight increase in plasmid delivery using other freeze-thawed transfection reagents, we postulate that freeze-thawing might prove to be useful for an even wider variety of transfection reagents.

  19. Malignant transformation of diploid human fibroblasts by transfection of oncogenes. Part 2, Progress report, July 1989--June 1992

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, J.J.

    1992-12-31

    This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.

  20. In vitro transfection of the hepatitis B virus PreS2 gene into the human hepatocarcinoma cell line HepG2 induces upregulation of human telomerase reverse transcriptase

    International Nuclear Information System (INIS)

    Liu Hua; Luan Fang; Ju Ying; Shen Hongyu; Gao Lifen; Wang Xiaoyan; Liu Suxia; Zhang Lining; Sun Wensheng; Ma Chunhong

    2007-01-01

    The preS2 domain is the minimal functional unit of transcription activators that is encoded by the Hepatitis B virus (HBV) surface (S) gene. It is present in more than one-third of the HBV-integrates in HBV induced hepatocarcinoma (HCC). To further understand the functional role of PreS2 in hepatocytes, a PreS2 expression plasmid, pcS2, was constructed and stably transfected into HepG2 cells. We conducted growth curve and colony-forming assays to study the impact of PreS2 expression on cell proliferation. Cells transfected with PreS2 proliferated more rapidly and formed colonies in soft agar. PreS2 expressing cells also induced upregulation of human telomerase reverse transcriptase (hTERT) and telomerase activation by RT-PCR and the modified TRAP assay. Blocking expression of hTERT with antisense oligonuleotide reversed the growth rate in cells stably transfected with PreS2. Our data suggest that PreS2 may increase the malignant transformation of human HCC cell line HepG2 by upregulating hTERT and inducing telomerase activation

  1. In vitro transfection of the hepatitis B virus PreS2 gene into the human hepatocarcinoma cell line HepG2 induces upregulation of human telomerase reverse transcriptase

    Energy Technology Data Exchange (ETDEWEB)

    Hua, Liu [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Fang, Luan [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Ying, Ju [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Hongyu, Shen [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Lifen, Gao [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Xiaoyan, Wang [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Suxia, Liu [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Lining, Zhang [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Wensheng, Sun [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Chunhong, Ma [Institute of Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan 250012 (China); Key Laboratory for Experimental Teratology, Ministry of Education (China)]. E-mail: machunhong@sdu.edu.cn

    2007-04-06

    The preS2 domain is the minimal functional unit of transcription activators that is encoded by the Hepatitis B virus (HBV) surface (S) gene. It is present in more than one-third of the HBV-integrates in HBV induced hepatocarcinoma (HCC). To further understand the functional role of PreS2 in hepatocytes, a PreS2 expression plasmid, pcS2, was constructed and stably transfected into HepG2 cells. We conducted growth curve and colony-forming assays to study the impact of PreS2 expression on cell proliferation. Cells transfected with PreS2 proliferated more rapidly and formed colonies in soft agar. PreS2 expressing cells also induced upregulation of human telomerase reverse transcriptase (hTERT) and telomerase activation by RT-PCR and the modified TRAP assay. Blocking expression of hTERT with antisense oligonuleotide reversed the growth rate in cells stably transfected with PreS2. Our data suggest that PreS2 may increase the malignant transformation of human HCC cell line HepG2 by upregulating hTERT and inducing telomerase activation.

  2. Radionuclide reporter gene imaging for cardiac gene therapy

    International Nuclear Information System (INIS)

    Inubushi, Masayuki; Tamaki, Nagara

    2007-01-01

    In the field of cardiac gene therapy, angiogenic gene therapy has been most extensively investigated. The first clinical trial of cardiac angiogenic gene therapy was reported in 1998, and at the peak, more than 20 clinical trial protocols were under evaluation. However, most trials have ceased owing to the lack of decisive proof of therapeutic effects and the potential risks of viral vectors. In order to further advance cardiac angiogenic gene therapy, remaining open issues need to be resolved: there needs to be improvement of gene transfer methods, regulation of gene expression, development of much safer vectors and optimisation of therapeutic genes. For these purposes, imaging of gene expression in living organisms is of great importance. In radionuclide reporter gene imaging, ''reporter genes'' transferred into cell nuclei encode for a protein that retains a complementary ''reporter probe'' of a positron or single-photon emitter; thus expression of the reporter genes can be imaged with positron emission tomography or single-photon emission computed tomography. Accordingly, in the setting of gene therapy, the location, magnitude and duration of the therapeutic gene co-expression with the reporter genes can be monitored non-invasively. In the near future, gene therapy may evolve into combination therapy with stem/progenitor cell transplantation, so-called cell-based gene therapy or gene-modified cell therapy. Radionuclide reporter gene imaging is now expected to contribute in providing evidence on the usefulness of this novel therapeutic approach, as well as in investigating the molecular mechanisms underlying neovascularisation and safety issues relevant to further progress in conventional gene therapy. (orig.)

  3. Enhancement of DNA-transfection frequency by X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, Ryota; Fushimi, Kazuo; Hiraki, Yoshio; Namba, Masayoshi [Okayama University Medical School (Japan). Institute of Cellular and Molecular Biology

    1997-02-01

    This study was conducted to evaluate the frequency of DNA transfection into human cells following X-ray irradiation. We transfected plasmid DNA (pSV2neo) into human cells, HeLa and PA-1, by either calcium phosphate precipitation or the lipofection method immediately after irradiating the cells with various doses of X-rays. The transfection frequency was evaluated by counting the number of G418-resistant colonies. When circular plasmid DNA was used, irradiation up to a dose of 2 Gy dose-dependently increased the transfection frequency, which reached a maximum of 5 to 10-fold that of the control unirradiated cells. When linear plasmid DNA was used, the transfection frequency was 2 times higher than that of circular DNA. All five of the clones that were randomly chosen expressed the transfected neo gene. In addition, the pSV2neo gene was randomly integrated into the genomic DNA of each clone. These findings indicate that X-ray treatment can facilitate foreign DNA transfer into human cells and that radiation-induced DNA breaks may promote the insertion of foreign DNA into host DNA. The enhancement of DNA transfection with X-rays may be instrumental in practicing gene therapy. (author)

  4. Enhancement of DNA-transfection frequency by X-rays

    International Nuclear Information System (INIS)

    Iwamoto, Ryota; Fushimi, Kazuo; Hiraki, Yoshio; Namba, Masayoshi

    1997-01-01

    This study was conducted to evaluate the frequency of DNA transfection into human cells following X-ray irradiation. We transfected plasmid DNA (pSV2neo) into human cells, HeLa and PA-1, by either calcium phosphate precipitation or the lipofection method immediately after irradiating the cells with various doses of X-rays. The transfection frequency was evaluated by counting the number of G418-resistant colonies. When circular plasmid DNA was used, irradiation up to a dose of 2 Gy dose-dependently increased the transfection frequency, which reached a maximum of 5 to 10-fold that of the control unirradiated cells. When linear plasmid DNA was used, the transfection frequency was 2 times higher than that of circular DNA. All five of the clones that were randomly chosen expressed the transfected neo gene. In addition, the pSV2neo gene was randomly integrated into the genomic DNA of each clone. These findings indicate that X-ray treatment can facilitate foreign DNA transfer into human cells and that radiation-induced DNA breaks may promote the insertion of foreign DNA into host DNA. The enhancement of DNA transfection with X-rays may be instrumental in practicing gene therapy. (author)

  5. Correlation between cationic lipid-based transfection and cell division

    Energy Technology Data Exchange (ETDEWEB)

    Kirchenbuechler, Inka; Kirchenbuechler, David; Elbaum, Michael, E-mail: michael@elbaum.ac.il

    2016-07-01

    We evaluate the temporal relation between protein expression by cationic lipid-mediated transfection and cell division using time lapse fluorescence microscopy. Detailed image analysis provides new insights on the single cell level while simultaneously achieving appropriate statistics. Earlier evidence by less direct methods such as flow cytometry indicates a primary route for transfection involving nuclear envelope breakdown, but also suggests the existence of a pathway independent of mitosis. We confirm and quantify both mechanisms. We found the timing for successful transfection to be unexpectedly flexible, contrary to assertions of a narrow time window. Specifically, cells dividing more than 24 h after exposure to the transfection medium express the probed protein at a comparable level to cells in a mitotic state during or shortly after transfection. This finding can have a profound impact on the guidance and development of non-viral gene delivery materials. - Highlights: • Cationic lipid-based transfection supports protein expression without cell division. • Protein expression is unrelated to cell cycle status at the time of transfection. • Time-lapse imaging provides direct evaluation without statistical averaging. • Lipoplex dissociation is a likely target for improvement of transfection efficiency.

  6. Combination therapy and evaluation of therapeutic effect in hepatocellular carcinoma cell using triple reporter genes; containing for NIS, HSV1-sr39tk and GFP

    Energy Technology Data Exchange (ETDEWEB)

    Lee, You La; Lee, Yong Jin; Ahn, Sohn Joo; Ahn, Byeong Cheol; Lee, Sang Woo; Yoo, Jeong Soo; Lee, Jae Tae [Kyungpook National University, Daegu (Korea, Republic of)

    2007-07-01

    To identify therapeutic effect after combine Sodium Iodine Symporter (NIS) and Mutant Herpes-simplex virus type 1 sr39tk (HSV1-sr39tk) expression in hepatocellular carcinoma cell, we transfected triple gene and investigated the properties of these gene ability in hepatocellular carcinoma cell line. After making vector with gene encoding a fusion protein comprised of HSV1-sr39tk and green florescence protein (GFP), to make triple reporter genes NIS gene was further fused to the vector using IRES vector. The vector expressing triple reporter gene was transfected to the Huh-7 cell line using liposome. Functions of hNIS and HSV1-sr39tk expression were confirmed by radio iodine uptake with and without perchlorate and [3H]-penciclovir (3-H PCV) uptake, respectively. To evaluate therapeutic effect in vitro, GCV and I-131 was treated in Huh-7/NTG cell and dual therapy performed. An animal imaging acquired using Optix and microPET in vivo. I-125 uptake was increased up to 100-fold compare to that of non-transfected cells. The transfected cell accumulated H-3 PCV up to 53 times higher at 2 hour than that of non-transfected cells. With fluorescence microscopy, green fluorescence was detected in the transfected cell. In cytotoxic studies, the cell viability of Huh-7/NTG cell was decreased to 41 % of control cell at 10ug/ml GCV concentrations. The survival rate of the Huh-7/NTG cell treated with I-131 decreased up to 16%. In I-131 and GCV dual therapy, Huh-7/NTG cell survival rate decreased up to 4%. In animal studies, Huh-7/NTG tumors showed higher uptake of 18F-FHBG and I-124 than Huh-7 tumors. GFP signal is also higher in Huh-7/NTG tumor than control. We successfully constructed a vector with delivery two therapeutic genes and one reporter gene and transfected the vector to a Huh-7 cell. The hepatocellular carcinoma cell transfected with the vector can be treated with GCV and I-131. The effect of dual gene therapy could be easily assessed by the optical reporter gene imaging.

  7. Immunoliposome-mediated delivery of neomycin phosphotransferase for the lineage-specific selection of differentiated/committed stem cell progenies: potential advantages over transfection with marker genes, fluorescence-activated and magnetic affinity cell-sorting.

    Science.gov (United States)

    Heng, Boon Chin; Cao, Tong

    2005-01-01

    A major challenge in the therapeutic application of stem cells in regenerative medicine is the lineage-specific selection of their committed/differentiated progenies for transplantation. This is necessary to avoid engraftment of undesired lineages at the transplantation site, i.e. fibroblastic scar tissue, as well as to enhance the efficacy of transplantation therapy. Commonly used techniques for lineage-specific selection of committed/differentiated stem cell progenies include marker gene transfection, fluorescence-activated (FACS) and magnetic-affinity (MACS) cell-sorting. Nevertheless, these have their disadvantages for therapeutic applications. Marker gene transfection invariably leads to permanent genetic modification of stem cells, which in turn limits their use in human clinical therapy due to overwhelming ethical and safety concerns. FACS requires expensive instrumentation and highly-skilled personnel, and is unsuited for handling bulk quantities of cells that would almost certainly be required for transplantation therapy. MACS is a cheaper alternative, but the level of purity attained is also reduced. A possible novel approach that has yet to be investigated is immunoliposome-mediated delivery of neomycin phosphotranferase (NPT) for lineage-specific selection of stem cell progenies. This would avoid permanent genetic modification to the cell, unlike recombinant NPT expression linked to activation of specific promoter sequences. Moreover, it could potentially provide a much more practical and cost-effective alternative for handling bulk quantities of cells that would be required for transplantation therapy, as compared to FACS or MACS. As such, this alternative approach needs to be rigorously investigated, in view of its potentially useful applications in stem cell therapeutics.

  8. A pH and Redox Dual Responsive 4-Arm Poly(ethylene glycol-block-poly(disulfide histamine Copolymer for Non-Viral Gene Transfection in Vitro and in Vivo

    Directory of Open Access Journals (Sweden)

    Kangkang An

    2014-05-01

    Full Text Available A novel 4-arm poly(ethylene glycol-b-poly(disulfide histamine copolymer was synthesized by Michael addition reaction of poly(ethylene glycol (PEG vinyl sulfone and amine-capped poly(disulfide histamine oligomer, being denoted as 4-arm PEG-SSPHIS. This copolymer was able to condense DNA into nanoscale polyplexes (<200 nm in average diameter with almost neutral surface charge (+(5–10 mV. Besides, these polyplexes were colloidal stable within 4 h in HEPES buffer saline at pH 7.4 (physiological environment, but rapidly dissociated to liberate DNA in the presence of 10 mM glutathione (intracellular reducing environment. The polyplexes also revealed pH-responsive surface charges which markedly increased with reducing pH values from 7.4–6.3 (tumor microenvironment. In vitro transfection experiments showed that polyplexes of 4-arm PEG-SSPHIS were capable of exerting enhanced transfection efficacy in MCF-7 and HepG2 cancer cells under acidic conditions (pH 6.3–7.0. Moreover, intravenous administration of the polyplexes to nude mice bearing HepG2-tumor yielded high transgene expression largely in tumor rather other normal organs. Importantly, this copolymer and its polyplexes had low cytotoxicity against the cells in vitro and caused no death of the mice. The results of this study indicate that 4-arm PEG-SSPHIS has high potential as a dual responsive gene delivery vector for cancer gene therapy.

  9. Development of an androgen reporter gene assay (AR-LUX) utilizing a human cell line with an endogenously regulated androgen receptor

    NARCIS (Netherlands)

    Blankvoort, B.M.G.; Groene, E.M. de; Meeteren-Kreikamp, A.P. van; Witkamp, R.F.; Rodenburg, R.J.T.; Aarts, J.M.M.J.G.

    2001-01-01

    The aim of the work described in this report is to develop and characterize a cell-based androgen reporter assay. For this purpose, the androgen receptor (AR) expressing human breast cancer cell line T47D was stably transfected with a luciferase gene under transcriptional control of the PB-ARE-2

  10. Feasibility of sodium/iodide symporter gene as a new imaging reporter gene: comparison with HSV1-tk

    International Nuclear Information System (INIS)

    Shin, Jae Hoon; Chung, June-Key; Lee, Yong Jin; Kim, Kwang Il; Kang, Joo Hyun; Jeong, Jae Min; Lee, Dong Soo; Kim, Chul Woo; Lee, Myung Chul

    2004-01-01

    Positron emission tomography (PET) imaging reporter genes, such as HSV1-tk and D 2 receptor genes, make it possible to visualise gene expression non-invasively and repetitively in vivo. However, these systems require the synthesis of complicated substrates and the availability of expensive PET equipment. Expression of the sodium/iodide symporter (NIS) gene can be easily monitored with radioiodines and technetium-99m using a gamma camera. To evaluate the possibility of using NIS as an imaging reporter gene, we compared its characteristics with those of the conventional HSV1-tk gene. The CM cell line was made by transfecting the HSV1-tk gene into CT-26 (mouse colon carcinoma cell line). The CTN and CMN cell lines were then made by transfecting the NIS gene into CT-26 and CM. We measured the uptake of iodine-125 iodovinyldeoxyuridine ([ 125 I]IVDU) and 125 I to evaluate the expression of the HSV1-tk and NIS genes, respectively. Each cell line was injected into four flank sites in Balb/c mice. The biodistribution study was performed after intravenously injecting [ 125 I]IVDU and 131 I, and 131 I scintigraphy was performed for the evaluation of NIS expression. In vitro studies indicated that CTN and CMN had 40- to 79-fold and 150- to 256-fold higher uptake of 125 I than CT-26 and CM, respectively. Furthermore, CM and CMN showed 57- to 69-fold higher uptake of [ 125 I]IVDU than CT-26 and CTN. NIS gene expression and 125 I accumulation were found to be directly correlated (R 2 =0.923), as were HSV1-tk gene expression and [ 125 I]IVDU accumulation (R 2 =0.956). Calculated signal per unit NIS and HSV1-tk mRNA expression was 23,240±3,755 cpm and 34,039±5,346 cpm, respectively. In vivo study indicated that CTN and CMN had 2.3- and 5.8-fold higher uptake of 131 I than CT-26 and CM, and 1.8- and 3.5-fold higher uptake of [ 125 I]IVDU than CT-26 and CTN. Scintigraphy using 131 I easily visualised CTN and CMN tumours. In conclusion, the NIS gene may be viewed as an imaging

  11. Molecular genetic transfection of the coccidian parasite Sarcocystis neurona.

    Science.gov (United States)

    Gaji, Rajshekhar Y; Zhang, Deqing; Breathnach, Cormac C; Vaishnava, Shipra; Striepen, Boris; Howe, Daniel K

    2006-11-01

    Sarcocystis neurona is an apicomplexan parasite that is the major cause of equine protozoal myeloencephalitis (EPM). The biology of this pathogen remains poorly understood in part due to unavailability of molecular genetic tools. Hence, with an objective to develop DNA transfection capabilities for S. neurona, the 5' flanking region of the SnSAG1 gene was isolated from a genomic library and used to construct expression plasmids. In transient assays, the reporter molecules beta-galactosidase (beta-gal) and yellow fluorescent protein (YFP) could be detected in electroporated S. neurona, thereby confirming the feasibility of transgene expression in this organism. Stable transformation of S. neurona was achieved using a mutant dihydrofolate reductase thymidylate synthase (DHFR-TS) gene of Toxoplasma gondii that confers resistance to pyrimethamine. This selection system was used to create transgenic S. neurona that stably express beta-gal and YFP. As shown in this study, these transgenic clones can be useful for analyzing growth rate of parasites in vitro and for assessing drug sensitivities. More importantly, the DNA transfection methods described herein should greatly facilitate studies examining intracellular parasitism by this important coccidian pathogen.

  12. Investigation progress of PET reporter gene imaging

    International Nuclear Information System (INIS)

    Chen Yumei; Huang Gang

    2006-01-01

    Molecular imaging for gene therapy and gene expression has been more and more attractive, while the use of gene therapy has been widely investigated and intense research have allowed it to the clinical setting in the last two-decade years. In vivo imaging with positron emission tomography (PET) by combination of appropriate PET reporter gene and PET reporter probe could provide qualitative and quantitative information for gene therapy. PET imaging could also obtain some valuable parameters not available by other techniques. This technology is useful to understand the process and development of gene therapy and how to apply it into clinical practice in the future. (authors)

  13. Protein kinase A inhibition modulates the intracellular routing of gene delivery vehicles in HeLa cells, leading to productive transfection

    NARCIS (Netherlands)

    Rehman, Zia Ur; Hoekstra, Dick; Zuhorn, Inge S.

    2011-01-01

    Cellular entry of nanoparticles for drug- and gene delivery relies on various endocytic pathways, including clathrin-and caveolae-mediated endocytosis. To improve delivery, i.e., the therapeutic and/or cell biological impact, current efforts are aimed at avoiding processing of the carriers along the

  14. MRI Reporter Genes for Noninvasive Molecular Imaging

    Directory of Open Access Journals (Sweden)

    Caixia Yang

    2016-05-01

    Full Text Available Magnetic resonance imaging (MRI is one of the most important imaging technologies used in clinical diagnosis. Reporter genes for MRI can be applied to accurately track the delivery of cell in cell therapy, evaluate the therapy effect of gene delivery, and monitor tissue/cell-specific microenvironments. Commonly used reporter genes for MRI usually include genes encoding the enzyme (e.g., tyrosinase and β-galactosidase, the receptor on the cells (e.g., transferrin receptor, and endogenous reporter genes (e.g., ferritin reporter gene. However, low sensitivity limits the application of MRI and reporter gene-based multimodal imaging strategies are common including optical imaging and radionuclide imaging. These can significantly improve diagnostic efficiency and accelerate the development of new therapies.

  15. The construction and identification of hypoxia-regulated recombinant plasmid with reporter gene hNIS

    International Nuclear Information System (INIS)

    Hu Qunchao; Wu Jinchang; Zhou Jundong; Gu Ke

    2011-01-01

    Objective: To construct pShuttle-5 × HRE-CMV-NIS recombinant plasmid regulated by hypoxia-responsive element, which can possibly by used to detect the expression of hypoxia induced factor-α (HIF-1α) gene under hypoxia condition. Methods: Artificially synthesize the nucleotide sequences of five copies of hypoxia response elements (HREs) were cloned into pGL3-promoter vector to construct pGL3-promoter-5 × HRE vector. Human sodium/iodide symporter (hNIS) gene cDNA was amplified from human genome by RT-PCR, and subcloned into pGL3-promoter-5 × HRE vector then was sequenced. After treated with CoCl 2 as hypoxia mimic, HEK293 cells were transfected with recombinant plasmid with hNIS gene, while cells treated with DMSO as the control. Meanwhile, pcDNA3.1-HIF-1α and recombinant hNIS gene vectors were transfected into HEK293 cells at the ratio of 3 to 1, while co-transfection with pcDNA3.1 and pShuttle-NIS vectors cells were taken as the control. NIS mRNA expression was analyzed by qRT-PCR while function of NIS protein was tested by 99m TcO 4 - -uptake. Results: The sequence data of hNIS gene in recombinant plasmid were in accordance with those reported in the literatures. Compared with control groups, HEK293 cells co-transfected with both pShuttle-5 × HRE-CMV-NIS and HIF-1α gene vectors and CoCl 2 -treated after pShuttle-NIS transfecting presented higher mRNA expressions of NIS and 99m TcO 4 - uptake (P<0.01). Conclusion: HIF-1α can be bound to and activate pShuttle-5 × HRE-CMV-NIS in cells to accumulate radioactive nuclide 99m TcO 4 - and this technique is potential for detection of expression and activity of HIF-1α, the indicator of cell hypoxia. (authors)

  16. Transfection of bone marrow derived cells with immunoregulatory proteins.

    Science.gov (United States)

    Khantakova, Julia N; Silkov, Alexander N; Tereshchenko, Valeriy P; Gavrilova, Elena V; Maksyutov, Rinat A; Sennikov, Sergey V

    2018-03-23

    In vitro electroporation gene transfer was first performed in 1982. Today, this technology has become one of the major vehicles for non-viral transfection of cells. All non-viral transfections, such as calcium phosphate precipitation, lipofection, and magnetic transfection, have been shown to achieve a transfection efficiency of up to 70% in commonly used cell lines, but not in primary cells. Here we describe the use of electroporation to transfect primary mouse bone marrow-derived cells, such as macrophages (Mφ) and dendritic cells (DCs) with high efficiencies (45%-72%) and minimal cell death. The transfection efficiencies and cell death varied depending on the culture duration of the DCs and Mφ. Moreover, the electroporation efficiency was increased when conditioning medium was used for culturing the cells. Furthermore, we demonstrated that measuring the plasmid-encoded secreted proteins is a highly sensitive method for determining the transfection efficiency. In summary, electroporation with plasmid vectors is an efficient method for producing DCs and Mφ with transient expression of immunoregulatory proteins. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Transfection of bovine spermatogonial stem cells in vitro.

    Science.gov (United States)

    Tajik, P; Hoseini Pajooh, Kh; Fazle Elahi, Z; Javdani Shahedin, G; Ghasemzadeh-Nava, H

    2017-01-01

    Spermatogonial stem cells (SSCs) are the only stem cells in adults that can transfer genetic information to the future generations. Considering the fact that a single SSC gives rise to a vast number of spermatozoa, genetic manipulation of these cells is a potential novel technology with feasible application to various animal species. The aim of this study was to evaluate enhanced green fluorescent protein (EGFP) gene transfection into bovine SSCs via liposome carrier and assess the best incubation day in uptake exogenous gene by SSCs. Transfection efficiency of EGFP gene with lipofectamine 2000 was determined in days following each three day of transfection (day 4, 6 and 8 of the culture) by fluorescent microscope. Results showed that the transfected cells through lipofection increased significantly (Ptransfection in comparison with those of the control groups. The transfected SSCs were higher in comparison with those of the free exogenous gene carrier groups (Ptransfection proceeds at day four. It was concluded that lipofectamine can be used safely for direct loading exogenous DNA to SSCs particularly during the fourth day of culture.

  18. SPECT imaging of cardiac reporter gene expression in living rabbits

    International Nuclear Information System (INIS)

    Liu Ying; Lan Xiaoli; Zhang Liang; Wu Tao; Jiang Rifeng; Zhang Yongxue

    2009-01-01

    This work is to demonstrate feasibility of imaging the expression of herpes simplex virus 1-thymidine kinase (HSVI-tk) reporter gene in rabbits myocardium by using the reporter probe 131 I-2'-fluoro-2'-deoxy-l-β-D-arabinofuranosyl-5-iodouracil ( 131 I-FIAU) and SPECT. Rabbits of the study group received intramyocardial injection of Ad5-tk and control group received aseptic saline injection. Two sets of experiments were performed on the study group. Rabbits of the 1st set were injected with 131 I-FIAU 600 μCi at Day 2 after intramyocardial transfection of Ad5-tk in 1xl0 9 , 5x10 8 , 1x10 8 , 5x10 7 and 1x10 7 pfu, and heart SPECT imaging was done at different hours. Rabbits of the 2nd were transferred various titers of Ad5-tk (1x10 9 , 5x10 8 , 1x10 8 , 5x10 7 , 1x10 7 pfu) to determine the threshold and optimal viral titer needed for detection of gene expression. Two days later, 131 I-FIAU was injected and heart SPECT imaging was performed at 6, 24 and 48 h, before killing them for gamma counting of the hearts. Reverse transcription-polymerase chain reaction (RT-PCR) was used to verify the transferred HSVI-tk gene expression. Semi-quantitative analysis derived of region of interest (ROI) of SPECT images and RT-PCR images was performed and the relationship of SPECT images with ex vivo gamma counting and mRNA level were evaluated. SPECT images conformed 131 I-FIAU accumulation in rabbits injected with Ad5-tk in the anterolateral wall. The optimal images quality was obtained at 24-48 h for different viral titers. The highest radioactivity in the focal myocardium was seen at 6 h, and then declined with time. The threshold was 5x10 7 pfu of virus titer. The result could be set better in 1-5x10 8 pfu by SPECT analysis and gamma counting. ROI-derived semi-quantitative study on SPECT images correlated well with ex vivo gamma counting and mRNA levels from RT-PCR analysis. The HSVI-tk/ 131 I-FIAU reporter gene/reporter probe system is feasible for cardiac SPECT reporter

  19. A versatile transfection assay system to evaluate the biological effects of diverse industrial chemicals.

    Science.gov (United States)

    Koizumi, Shinji; Ohno, Shotaro; Otsuka, Fuminori

    2012-01-01

    Gene expression processes are now recognized as important targets of the toxic effects exerted by industrial chemicals. The transient transfection assay is a powerful tool to evaluate such effects. Thus, we developed a versatile assay system by constructing a basic reporter plasmid in which the regulatory DNA sequence to be studied can easily be substituted. To verify the performance of this system, reporter plasmids carrying any of the three distinct regulatory sequences, estrogen responsive element (ERE), glucocorticoid responsive element (GRE) and xenobiotic responsive element (XRE) were constructed. After transfection of human cells, these plasmids successfully expressed the relevant reporter genes in response to specific inducers, β-estradiol, dexamethasone and 3-methylcholanthrene, respectively. Several industrial chemicals were assayed using these reporter plasmids, and the ability of p-dimethylaminoazobenzene to elevate GRE- and XRE-mediated transcription was detected. α-Naphthylamine and o-tolidine were also observed to increase the XRE-mediated response. The transfection assay system established here will be useful to evaluate the effects of a wide variety of industrial chemicals.

  20. Newly constructed stable reporter cell lines for mechanistic studies on electrophile-responsive element-mediated gene expression reveal a role for flavonoid planarity.

    NARCIS (Netherlands)

    Boerboom, A.M.A.; Vermeulen, M.; Woude, H. van der; Bremer, B.I.; Lee-Hilz, Y.Y.; Kampman, E.; Bladeren, P.J. van; Rietjens, I.M.C.M.; Aarts, J.

    2006-01-01

    The electrophile-responsive element (EpRE) is a transcriptional enhancer involved in cancer-chemoprotective gene expression modulation by certain food components. Two stably transfected luciferase reporter cell lines were developed, EpRE(hNQO1)-LUX and EpRE(mGST-Ya)-LUX, based on EpRE sequences from

  1. Newly constructed stable reporter cell lines for mechanistic studies on electrophile-responsive element-mediated gene expression reveal a role for flavonoid planarity

    NARCIS (Netherlands)

    Boerboom, A.M.J.F.; Vermeulen, M.; Woude, H. van der; Bremer, B.I.; Lee-Hilz, Y.Y.; Kampman, E.; Bladeren, P.J. van; Rietjens, I.M.C.M.; Aarts, J.M.M.J.G.

    2006-01-01

    The electrophile-responsive element (EpRE) is a transcriptional enhancer involved in cancer-chemoprotective gene expression modulation by certain food components. Two stably transfected luciferase reporter cell lines were developed, EpRE(hNQO1)-LUX and EpRE(mGST-Ya)-LUX, based on EpRE sequences from

  2. Lipophosphoramidate-based bipolar amphiphiles: their syntheses and transfection properties.

    Science.gov (United States)

    Berchel, Mathieu; Le Gall, Tony; Lozach, Olivier; Haelters, Jean-Pierre; Montier, Tristan; Jaffrès, Paul-Alain

    2016-03-14

    Six new cationic bolaamphiphiles (also called bipolar amphiphiles, bolaform amphiphiles, or bolalipids) were readily prepared by a thiol-ene click reaction that engaged a mercapto-alcohol (mercapto-ethanol or mercapto-hexanol) and a cationic based lipophosphoramidate. The cationic lipophosphoramidates contain two lipid chains that end in an alkene group and a selected cationic polar head group (trimethylammonium, dimethyl hydroxyethyl ammonium, or methylimidazolium). These compounds were formulated in water (with or without DOPE as a colipid) to produce supramolecular aggregates. These aggregates, before (i.e. bolasomes) and after (i.e. bolaplexes) mixing with plasmid DNA (pDNA) at various charge ratios, were characterized with regard to their sizes and zeta potentials. In the case of bolasomes, the suspensions were unstable since precipitation occurred after only a few hours at room temperature. On the other hand, bolaplex formulations exhibited clearly a better colloidal stability. Then, the gene delivery properties of the cationic bolasomes were investigated using two human-derived epithelial cell lines (A549 and 16HBE). Compared to the commercially available lipofection reagent (Lipofectamine), most of the cationic bolaamphiphiles were able to efficiently transfect these cells when they were formulated with DOPE in a 1 : 1 molar ratio. We report herein that bolaamphiphiles possessing a trimethylammonium or a dimethyl hydroxyethyl ammonium head group were the most efficient in terms of transfection efficiency while exhibiting no significant cytotoxicity.

  3. Feasibility of dual reporter gene in rat myoblast cell line using human sodium iodide symporter (hNIS) and enhanced green fluorescent protein (EGFP) gene

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Jin; Lee, You La; Ahn, Sohn Joo; Choi, Chang Ik; Lee, Sang Woo; Ahn, Byeong Cheol; Lee, Jae Tae [School of Medicine, Kyungpook National University, Daegu (Korea, Republic of)

    2007-07-01

    To develop a non-invasive combined imaging method of gamma camera and optical imaging to assess rat myoblast cell line, H9c2, we constructed retrovirus containing hNIS and EGFP gene, and transfected to rat myoblast cell and monitored hNIS and EGFP expression. Rat myoblast cell line, H9C2, was transfected with hNIS and EGFP gene using retrovirus (H9C2-NG). The expression of hNIS and EGFP gene was determined by RT-PCR and fluorescence microscopy, respectively. The uptake and efflux of I-125 were measured in the transfected and wild type cell lines. Each cell line was injected to 4 flank sites (H9c2: 1X107 or 2X107, H9C2-NG: 1X107 or 2X107) in nude mouse. Scintigraphic image was performed at 3h, 1 day after H9C2 and H9C2-NG cell inoculation. We performed gamma camera and animal PET imaging to evaluate NIS expression. Also, GFP image obtained using optical imaging system. The expression of hNIS and EGFP gene was confirmed by RT-PCR. In iodide uptake, H9C2-NG cells accumulated 274.52.2 pmol/ mg protein at 30 min. But wild type cell line did not uptake iodide. In fluorescent microscopy, H9C2-NG cells were highly fluorescent than that of H9C2 cells. In iodide efflux study, 50% of radioactivity flowed out during the first 10min. Scintigraphy showed increased uptake of Tc-99m in H9c2-NG than in H9C2 for 1 day. Also, H9C2-NG cells showed high signal-to-background fluorescent spots in animal body. In this study, NIS and EGFP reporter gene were successfully transfected by a retrovirus in myoblast cell line, and the transfected cell can be easily visualized in vivo. These results suggest that NIS and EGFP gene has an excellent feasibility as a reporter gene, and it can be used to monitor cell trafficking for monitoring.

  4. STRO-1 selected rat dental pulp stem cells transfected with adenoviral-mediated human bone morphogenetic protein 2 gene show enhanced odontogenic differentiation.

    NARCIS (Netherlands)

    Yang, X.; Kraan, P.M. van der; Dolder, J. van den; Walboomers, X.F.; Bian, Z.; Fan, M.; Jansen, J.A.

    2007-01-01

    Dental pulp stem cells harbor great potential for tissue-engineering purposes. However, previous studies have shown variable results, and some have reported only limited osteogenic and odontogenic potential.Because bone morphogenetic proteins (BMPs) are well-established agents to induce bone and

  5. Uptake of DNA by cancer cells without a transfection reagent

    Directory of Open Access Journals (Sweden)

    Yanping Kong

    Full Text Available Abstract Background Cancer cells exhibit elevated levels of glucose uptake and may obtain pre-formed, diet-derived fatty acids from the bloodstream to boost their rapid growth; they may also use nucleic acid from their microenvironment. The study of processing nucleic acid by cancer cells will help improve the understanding of the metabolism of cancer. DNA is commonly packaged into a viral or lipid particle to be transferred into cells; this process is called transfection in laboratory. Cancer cells are known for having gene mutations and the evolving ability of endocytosis. Their uptake of DNAs might be different from normal cells; they may take in DNAs directly from the environment. In this report, we studied the uptake of DNAs in cancer cells without a transfection reagent. Methods A group of DNA fragments were prepared with PCR and labeled with isotope phosphorous-32 to test their uptake by Huh 7 (liver cancer and THLE3 (normal liver cells after incubation overnight by counting radioactivity of the cells’ genomic DNA. Multiple cell lines including breast cancer and lung cancer were tested with the same method. DNA molecules were also labeled with fluorescence to test the location in the cells using a kit of “label it fluorescence in situ hybridization (FISH” from Mirus (USA. Results The data demonstrated that hepatocellular carcinoma cells possess the ability to take in large DNA fragments directly without a transfection reagent whereas normal liver cells cannot. Huh7 and MDA-MB231 cells displayed a significantly higher Rhodamine density in the cytoplasmic phagosomes and this suggests that the mechanism of uptake of large DNA by cancer cells is likely endocytosis. The efficacy of uptake is related to the DNA’s size. Some cell lines of lung cancer and breast cancer also showed similar uptake of DNA. Conclusions In the present study, we have revealed the evidence that some cancer cells, but not nontumorigenic cells, can take DNA

  6. Cationic lipids: molecular structure/ transfection activity relationships and interactions with biomembranes.

    Science.gov (United States)

    Koynova, Rumiana; Tenchov, Boris

    2010-01-01

    Abstract Synthetic cationic lipids, which form complexes (lipoplexes) with polyanionic DNA, are presently the most widely used constituents of nonviral gene carriers. A large number of cationic amphiphiles have been synthesized and tested in transfection studies. However, due to the complexity of the transfection pathway, no general schemes have emerged for correlating the cationic lipid chemistry with their transfection efficacy and the approaches for optimizing their molecular structures are still largely empirical. Here we summarize data on the relationships between transfection activity and cationic lipid molecular structure and demonstrate that the transfection activity depends in a systematic way on the lipid hydrocarbon chain structure. A number of examples, including a large series of cationic phosphatidylcholine derivatives, show that optimum transfection is displayed by lipids with chain length of approximately 14 carbon atoms and that the transfection efficiency strongly increases with increase of chain unsaturation, specifically upon replacement of saturated with monounsaturated chains.

  7. Reduced expression of Autographa californica nucleopolyhedrovirus ORF34, an essential gene, enhances heterologous gene expression

    International Nuclear Information System (INIS)

    Salem, Tamer Z.; Zhang, Fengrui; Thiem, Suzanne M.

    2013-01-01

    Autographa californica multiple nucleopolyhedrovirus ORF34 is part of a transcriptional unit that includes ORF32, encoding a viral fibroblast growth factor (FGF) and ORF33. We identified ORF34 as a candidate for deletion to improve protein expression in the baculovirus expression system based on enhanced reporter gene expression in an RNAi screen of virus genes. However, ORF34 was shown to be an essential gene. To explore ORF34 function, deletion (KO34) and rescue bacmids were constructed and characterized. Infection did not spread from primary KO34 transfected cells and supernatants from KO34 transfected cells could not infect fresh Sf21 cells whereas the supernatant from the rescue bacmids transfection could recover the infection. In addition, budded viruses were not observed in KO34 transfected cells by electron microscopy, nor were viral proteins detected from the transfection supernatants by western blots. These demonstrate that ORF34 is an essential gene with a possible role in infectious virus production.

  8. Reduced expression of Autographa californica nucleopolyhedrovirus ORF34, an essential gene, enhances heterologous gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Salem, Tamer Z. [Department of Entomology, Michigan State University, East Lansing, MI 48824 (United States); Department of Microbial Molecular Biology, AGERI, Agricultural Research Center, Giza 12619 (Egypt); Division of Biomedical Sciences, Zewail University, Zewail City of Science and Technology, Giza 12588 (Egypt); Zhang, Fengrui [Department of Entomology, Michigan State University, East Lansing, MI 48824 (United States); Thiem, Suzanne M., E-mail: smthiem@msu.edu [Department of Entomology, Michigan State University, East Lansing, MI 48824 (United States); Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824 (United States)

    2013-01-20

    Autographa californica multiple nucleopolyhedrovirus ORF34 is part of a transcriptional unit that includes ORF32, encoding a viral fibroblast growth factor (FGF) and ORF33. We identified ORF34 as a candidate for deletion to improve protein expression in the baculovirus expression system based on enhanced reporter gene expression in an RNAi screen of virus genes. However, ORF34 was shown to be an essential gene. To explore ORF34 function, deletion (KO34) and rescue bacmids were constructed and characterized. Infection did not spread from primary KO34 transfected cells and supernatants from KO34 transfected cells could not infect fresh Sf21 cells whereas the supernatant from the rescue bacmids transfection could recover the infection. In addition, budded viruses were not observed in KO34 transfected cells by electron microscopy, nor were viral proteins detected from the transfection supernatants by western blots. These demonstrate that ORF34 is an essential gene with a possible role in infectious virus production.

  9. Transfection in perfused microfluidic cell culture devices: A case study.

    Science.gov (United States)

    Raimes, William; Rubi, Mathieu; Super, Alexandre; Marques, Marco P C; Veraitch, Farlan; Szita, Nicolas

    2017-08-01

    Automated microfluidic devices are a promising route towards a point-of-care autologous cell therapy. The initial steps of induced pluripotent stem cell (iPSC) derivation involve transfection and long term cell culture. Integration of these steps would help reduce the cost and footprint of micro-scale devices with applications in cell reprogramming or gene correction. Current examples of transfection integration focus on maximising efficiency rather than viable long-term culture. Here we look for whole process compatibility by integrating automated transfection with a perfused microfluidic device designed for homogeneous culture conditions. The injection process was characterised using fluorescein to establish a LabVIEW-based routine for user-defined automation. Proof-of-concept is demonstrated by chemically transfecting a GFP plasmid into mouse embryonic stem cells (mESCs). Cells transfected in the device showed an improvement in efficiency (34%, n = 3) compared with standard protocols (17.2%, n = 3). This represents a first step towards microfluidic processing systems for cell reprogramming or gene therapy.

  10. Advances in study of reporter gene imaging for monitoring gene therapy

    International Nuclear Information System (INIS)

    Mu Chuanjie; Zhou Jiwen

    2003-01-01

    To evaluate the efficiency of gene therapy, it is requisite to monitor localization and expression of the therapeutic gene in vivo. Monitoring expression of reporter gene using radionuclide reporter gene technique is the best method. Adenoviral vectors expressing reporter gene are constructed using gene fusion, bicistronic, double promoter or bidirectional transcriptional recombination techniques, and transferred into target cells and tissues, then injected radiolabeled reporter probes which couple to the reporter genes. The reporter genes can be imaged invasively, repeatedly, quantitatively with γ-camera, PET and SPECT. Recently, several reporter gene and reporter probe systems have been used in studies of gene therapy. The part of them has been used for clinic trials

  11. Epizone: Interlaboratory Ring Trial to Compare Dna Transfection Efficiencies

    DEFF Research Database (Denmark)

    Dory, Daniel; Albina, Emmanuel; Kwiatek, Olivier

    Chemical-based transfection of DNA into cultured cells is routinely used to study for example viral or cellular gene functions involved in virus replication, to analyse cellular defence mechanisms or develop specific strategies to interfere with virus replication. Other applications include rescu...

  12. Enhanced transfection efficiency and reduced cytotoxicity of novel lipid-polymer hybrid nanoplexes

    DEFF Research Database (Denmark)

    Jain, Sanyog; Kumar, Sandeep; Agrawal, Ashish Kumar

    2013-01-01

    The present study reports the development, characterization, and evaluation of novel polyelectrolytes stabilized lipoplexes as a nonviral vector for gene delivery. In order to achieve the advantage of both DOTAP (1,2-dioleoyl-3-trimethylammonium propane) and PEI (high transfection efficiency...... uptake and nuclear colocalization in comparison with DOTAP/PC, DOTAP/DOPE lipoplexes, and PEI polyplexes. Nanoplexes also exhibited 50-80, 11-12, 6-7, and 5-6 fold higher transfection efficiency in comparison with DOTAP/PC-lipoplexes, DOTAP/DOPE-lipoplexes, PEI-polyplexes, and lipofectamine, respectively......, and significantly lower toxicity in comparison with DOTAP/PC, DOTAP/DOPE lipoplexes, PEI polyplexes, and commercial lipofectamine....

  13. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    International Nuclear Information System (INIS)

    Wu Xuewen; Ding Dalian; Jiang Haiyan; XingXiaowei; Huang, Suping; Liu Hong; Chen Zhedong; Sun Hong

    2012-01-01

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI–nHAT, diameter = 73.09 ± 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2–NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector–gene complex (PEI–nHAT–pEGFPC2–NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector–gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector–gene complexes. Considering the high transfection efficiency in the vestibular system, PEI–nHAT may be a potential vector for

  14. Transfection using hydroxyapatite nanoparticles in the inner ear via an intact round window membrane in chinchilla

    Energy Technology Data Exchange (ETDEWEB)

    Wu Xuewen; Ding Dalian [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Jiang Haiyan [State University of New York at Buffalo, Center for Hearing and Deafness (United States); XingXiaowei [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Huang, Suping [Central South University, State Key Laboratory of Powder Metallurgy (China); Liu Hong [Central South University, Department of Otolaryngology Head and Neck Surgery, The Third Xiangya Hospital (China); Chen Zhedong [Central South University, State Key Laboratory of Powder Metallurgy (China); Sun Hong, E-mail: shjhaj@vip.163.com [Central South University, Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital (China)

    2012-01-15

    Hydroxyapatite nanoparticles (nHAT) are known to have excellent biocompatibility, and have attracted increasing attention as new candidates of non-viral vectors for gene therapy. In our previous studies, nHAT carrying a therapeutic gene and a reporter gene were successfully transfected into the spiral ganglion neurons in the inner ear of guinea pigs in vivo as well as in the cultured cell lines, although the transfection efficiencies were never higher than 30%. In this study, the surface modification of nHAT with polyethylenimine (PEI) was made (PEI-nHAT, diameter = 73.09 {+-} 27.32 nm) and a recombinant plasmid carrying enhanced green fluorescent protein (EGFP) gene and neurotrophin-3 (NT-3) gene was constructed as pEGFPC2-NT3. The PEI modified nHAT and the recombinant plasmid was then connected to form the nHAT-based vector-gene complex (PEI-nHAT-pEGFPC2-NT3). This complex was then placed onto the intact round window membranes of the chinchillas for inner ear transfection. Auditory brainstem response (ABR) was tested to evaluate auditory function. Green fluorescence of EGFP was observed using confocal microscopy 48 h after administering vector-gene complexes. There was no significant threshold shift in tone burst-evoked ABR at any tested frequency. Abundant, condensed green fluorescence was found in dark cells on both sides of the crista and around the macula of the utricle. Scattered EGFP signals were also detected in vestibular hair cells, some Schwann cells in the cochlear spiral ganglion region, some outer pillar cells in the organ of Corti, and a few cells in the stria vascularis. The density of green fluorescence-marked cells was obviously higher in the vestibular dark cell area than in other areas of the inner ear, suggesting that vestibular dark cells may have the ability to actively engulf the nHAT-based vector-gene complexes. Considering the high transfection efficiency in the vestibular system, PEI-nHAT may be a potential vector for gene therapy of

  15. Isolation of antigenic substances from HIV-1 envelope gp160 gene transfectants by mild acid elution and X-irradiation treatment. For the development of CTL-based immunotherapy

    International Nuclear Information System (INIS)

    Fujimoto, Chiaki; Nakagawa, Yohko; Shimizu, Masumi; Ohara, Kunitoshi; Takahashi, Hidemi

    2003-01-01

    Cytotoxic T lymphocytes (CTLs) play a central role in a broad spectrum of tumor immunity. Such CTLs generally recognize processed antigenic fragments in association with class I major histocompatibility complex (MHC) molecules. Thus, it is important to identify naturally processed antigens associated with class I MHC molecules to generate and activate antigen-specific CTLs. Those processed antigens fitted in the groove of class I MHC molecules are fixed by the β2-microglobulin. Mild acid elution is one method used to isolate antigenic fragments from class I MHC molecules on tumor cells by unfastening a clasp of β2-microglobulin, a critical component for stabilizing class I MHC molecules on the cell surface. Indeed, after the mild acid treatment, the expression of class I MHC molecules was temporarily down-modulated and a strong antigenic fraction for CTL recognition was obtained. To our surprise, such down-modulation of class I MHC molecule expression was also observed when the tumor cells were irradiated. Therefore, using human immunodeficiency virus type I (HIV-1) gp160 env gene transfectants, we examined the effect of X-irradiation on releasing the loaded antigenic fragments. Functional extracts were obtained from X-irradiated cell supernatants that sensitized syngeneic fibroblasts for specific CTL recognition, suggesting that X-irradiation extracts would also contain known antigenic epitopes. These results indicate that, in addition to the conventional mild acid elution treatment, X-irradiation method shown in this paper may provide a new approach for CTL-based vaccine development via isolating antigenic molecules from various tumors or virally infected cells. (author)

  16. Cell transfection as a tool to study growth hormone action

    DEFF Research Database (Denmark)

    Norstedt, G; Enberg, B; Francis, S

    1994-01-01

    The isolation of growth hormone receptor (GHR) cDNA clones has made possible the transfection of GHRs into cultured cells. Our aim in this minireview is to show how the application of such approaches have benefited GHR research. GH stimulation of cells expressing GHR cDNAs can cause an alteration...... is important in GH action. The GH signals are transmitted to the nucleus and GH regulated genes have now begun to be characterized. The ability to use cell transfection for mechanistic studies of GH action will be instrumental to define domains within the receptor that are of functional importance...

  17. Reporter gene assay for the quantification of the activity and neutralizing antibody response to TNFα antagonists

    DEFF Research Database (Denmark)

    Lallemand, Christophe; Kavrochorianou, Nadia; Steenholdt, Casper

    2011-01-01

    A cell-based assay has been developed for the quantification of the activity of TNFα antagonists based on human erythroleukemic K562 cells transfected with a NFκB regulated firefly luciferase reporter-gene construct. Both drug activity and anti-drug neutralizing antibodies can be quantified...... with a high degree of precision within 2h, and without interference from cytokines and other factors known to activate NFκB. The assay cells also contain the Renilla luciferase reporter gene under the control of a constitutive promoter that allows TNFα-induced firefly luciferase activity to be normalized...... relative to Renilla luciferase expression. Thus, results are independent of cell number or differences in cell viability, resulting in intra and inter assay coefficients of variation of 10% or less. Normalization of results relative to the expression of an internal standard also provides a means...

  18. Efficient transfection of Xenobiotic Responsive Element-biosensor plasmid using diether lipid and phosphatidylcholine liposomes in differentiated HepaRG cells.

    Science.gov (United States)

    Demazeau, Maxime; Quesnot, Nicolas; Ripoche, Nicolas; Rauch, Claudine; Jeftić, Jelena; Morel, Fabrice; Gauffre, Fabienne; Benvegnu, Thierry; Loyer, Pascal

    2017-05-30

    In this study, we evaluated cationic liposomes prepared from diether-NH 2 and egg phosphatidylcholine (EPC) for in vitro gene delivery. The impact of the lipid composition, i.e. the EPC and Diether-NH 2 molar ratio, on in vitro transfection efficiency and cytotoxicity was investigated using the human HEK293T and hepatoma HepaRG cells known to be permissive and poorly permissive cells for liposome-mediated gene transfer, respectively. Here, we report that EPC/Diether-NH 2 -based liposomes enabled a very efficient transfection with low cytotoxicity compared to commercial transfection reagents in both HEK293T and proliferating progenitor HepaRG cells. Taking advantage of these non-toxic EPC/Diether-NH 2 -based liposomes, we developed a method to efficiently transfect differentiated hepatocyte-like HepaRG cells and a biosensor plasmid containing a Xenobiotic Responsive Element and a minimal promoter driving the transcription of the luciferase reporter gene. We demonstrated that the luciferase activity was induced by a canonical inducer of cytochrome P450 genes, the benzo[a]pyrene, and two environmental contaminants, the fluoranthene, a polycyclic aromatic hydrocarbon, and the endosulfan, an organochlorine insecticide, known to induce toxicity and genotoxicity in differentiated HepaRG cells. In conclusion, we established a new efficient lipofection-mediated gene transfer in hepatocyte-like HepaRG cells opening new perspectives in drug evaluation relying on xenobiotic inducible biosensor plasmids. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Reporter gene imaging: potential impact on therapy

    International Nuclear Information System (INIS)

    Serganova, Inna; Blasberg, Ronald

    2005-01-01

    Positron emission tomography (PET)-based molecular-genetic imaging in living organisms has enjoyed exceptional growth over the past 5 years; this is particularly striking since it has been identified as a new discipline only within the past decade. Positron emission tomography is one of three imaging technologies (nuclear, magnetic resonance and optical) that has begun to incorporate methods that are established in molecular and cell biology research. The convergence of these disciplines and the wider application of multi-modality imaging are at the heart of this success story. Most current molecular-genetic imaging strategies are 'indirect,' coupling a 'reporter gene' with a complimentary 'reporter probe.' Reporter gene constructs can be driven by constitutive promoter elements and used to monitor gene therapy vectors and the efficacy of trans gene targeting and transduction, as well as to monitor adoptive cell-based therapies. Inducible promoters can be used as 'sensors' to regulate the magnitude of reporter gene expression and can be used to provide information about endogenous cell processes. Reporter systems can also be constructed to monitor mRNA stabilization and specific protein-protein interactions. Promoters can be cell specific and restrict transgene expression to certain tissue and organs. The translation of reporter gene imaging to specific clinical applications is discussed. Several examples that have potential for patient imaging studies in the near future include monitoring adenoviral-based gene therapy, oncolytic herpes virus therapy, adoptive cell-based therapies and Salmonella-based tumor-targeted cancer therapy and imaging. The primary translational applications of noninvasive in vivo reporter gene imaging are likely to be (a) quantitative monitoring of the gene therapy vector and the efficacy of transduction in clinical protocols, by imaging the location, extent and duration of transgene expression; (b) monitoring cell trafficking, targeting

  20. Specific transfection of inflamed brain by macrophages: a new therapeutic strategy for neurodegenerative diseases.

    Directory of Open Access Journals (Sweden)

    Matthew J Haney

    Full Text Available The ability to precisely upregulate genes in inflamed brain holds great therapeutic promise. Here we report a novel class of vectors, genetically modified macrophages that carry reporter and therapeutic genes to neural cells. Systemic administration of macrophages transfected ex vivo with a plasmid DNA (pDNA encoding a potent antioxidant enzyme, catalase, produced month-long expression levels of catalase in the brain resulting in three-fold reductions in inflammation and complete neuroprotection in mouse models of Parkinson's disease (PD. This resulted in significant improvements in motor functions in PD mice. Mechanistic studies revealed that transfected macrophages secreted extracellular vesicles, exosomes, packed with catalase genetic material, pDNA and mRNA, active catalase, and NF-κb, a transcription factor involved in the encoded gene expression. Exosomes efficiently transfer their contents to contiguous neurons resulting in de novo protein synthesis in target cells. Thus, genetically modified macrophages serve as a highly efficient system for reproduction, packaging, and targeted gene and drug delivery to treat inflammatory and neurodegenerative disorders.

  1. Biological Education of IVFRU and FIAU for HSV1-TK Reporter Gene Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Su Hee; Kim, Eun Jung; Lee, Eun Ah; Lee, Jong Chan; Choi, Tae Hyun; Lee, Kyo Chul; An, Gwang Il; Cheon, Gi Jeong [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2006-07-01

    The Herpes Simplex Virus Type1-thymidine kinase (HSV1-TK) system is a useful gene therapy monitoring method. HSV1-TK is one of the most widely used effector gene systems used for imaging gene expression, in association with its use as a reporter gene. It has resulted the development of a number of radiolabeled HSV1-TK substrates for the non-invasive detection of HSV1-TK expression. In non-invasive imaging of the HSV1-TK system, many nucleoside derivatives have been developed as prodrugs for tumor proliferation imaging or as anti-viral drugs. Prodrug activation or sucide gene therapy has been shown to be successful in potentiating the therapeutic index by sensitizing genetically modified tumor cells to various prodrugs or enhancing the action of commonly used chemotherapeutic agents. The most studied prodrug activation approaches involve transfection of tumors with HSV1-TK gene. (Z)-5-(2-iodovinyl)-2'-fluoro- 2'-deoxyuridine (IVFRU) possesses a 2'-fluoro substituent in the ribose configuration, is considered to protect IVFRU from enzyme mediated degradation in vivo. It is obviously potential substrates for HSV1-TK imaging. 2'-Fiuoro-2'-deoxy-1-{beta}-D-arabinofuranosyl- 5-iodo-uridine (FIAU), an anticancer drug widely used in clinical practice, is an analogue of thymidine. In a series of studies using adenovirus vector for gene transfer described the appropriate combination of exogenously introduced HSV1-TK as a 'marker/reporter gene' and radiolabelled FIAU as a 'marker substrate/reporter probe' for monitoring gene therapy and gene expression.

  2. Biological Education of IVFRU and FIAU for HSV1-TK Reporter Gene Monitoring

    International Nuclear Information System (INIS)

    Hong, Su Hee; Kim, Eun Jung; Lee, Eun Ah; Lee, Jong Chan; Choi, Tae Hyun; Lee, Kyo Chul; An, Gwang Il; Cheon, Gi Jeong

    2006-01-01

    The Herpes Simplex Virus Type1-thymidine kinase (HSV1-TK) system is a useful gene therapy monitoring method. HSV1-TK is one of the most widely used effector gene systems used for imaging gene expression, in association with its use as a reporter gene. It has resulted the development of a number of radiolabeled HSV1-TK substrates for the non-invasive detection of HSV1-TK expression. In non-invasive imaging of the HSV1-TK system, many nucleoside derivatives have been developed as prodrugs for tumor proliferation imaging or as anti-viral drugs. Prodrug activation or sucide gene therapy has been shown to be successful in potentiating the therapeutic index by sensitizing genetically modified tumor cells to various prodrugs or enhancing the action of commonly used chemotherapeutic agents. The most studied prodrug activation approaches involve transfection of tumors with HSV1-TK gene. (Z)-5-(2-iodovinyl)-2'-fluoro- 2'-deoxyuridine (IVFRU) possesses a 2'-fluoro substituent in the ribose configuration, is considered to protect IVFRU from enzyme mediated degradation in vivo. It is obviously potential substrates for HSV1-TK imaging. 2'-Fiuoro-2'-deoxy-1-β-D-arabinofuranosyl- 5-iodo-uridine (FIAU), an anticancer drug widely used in clinical practice, is an analogue of thymidine. In a series of studies using adenovirus vector for gene transfer described the appropriate combination of exogenously introduced HSV1-TK as a 'marker/reporter gene' and radiolabelled FIAU as a 'marker substrate/reporter probe' for monitoring gene therapy and gene expression

  3. Advances in study of molecular imaging reporte gene systems

    International Nuclear Information System (INIS)

    Wu Tao; An Rui

    2010-01-01

    The use of molecular imaging reporter gene systems has allowed gene therapy to move from the laboratory to the clinical application, which provides methodology to monitor the expression of therapeutic gene noninvasively and achieve quantitative outcome in vivo. Recently, the radionuclide reporter gene still is the focus many studies, but MRI and optical reporter gene have gradually played a important part in reporter gene systems. On the basis of combination of multi-subject, for example applied chemistry and molecular biology, more and more new modified reporter genes and molecular probes have spread out. This paper mainly introduces the advantages and disadvantages of reporter gene system and development trends. (authors)

  4. Rapid and sensitive reporter gene assays for detection of antiandrogenic and estrogenic effects of environmental chemicals

    DEFF Research Database (Denmark)

    Vinggaard, Anne; Jørgensen, E.C.B.; Larsen, John Christian

    1999-01-01

    Reports on increasing incidences in developmental abnormalities of the human male reproductive tract and the recent identifications of environmental chemicals with antiandrogenic activity necessitate the screening of a larger number of compounds in order to get an overview of potential antiandrog......Reports on increasing incidences in developmental abnormalities of the human male reproductive tract and the recent identifications of environmental chemicals with antiandrogenic activity necessitate the screening of a larger number of compounds in order to get an overview of potential...... antiandrogenic chemicals present in our environment. Thus, there is a great need for an effective in vitro screening method for (anti)androgenic chemicals. We have developed a rapid, sensitive, and reproducible reporter gene assay for detection of antiandrogenic chemicals. Chinese Hamster Ovary cells were...... calcium phosphate transfection method, this method has the advantage of being more feasible, as the assay can be scaled down to the microtiter plate format. Furthermore, the transfection reagent is noncytotoxic, allowing its addition together with the test compounds thereby reducing the hands...

  5. Biodegradable charged polyester-based vectors (BCPVs) as an efficient non-viral transfection nanoagent for gene knockdown of the BCR-ABL hybrid oncogene in a human chronic myeloid leukemia cell line

    Science.gov (United States)

    Yang, Chengbin; Panwar, Nishtha; Wang, Yucheng; Zhang, Butian; Liu, Maixian; Toh, Huiting; Yoon, Ho Sup; Tjin, Swee Chuan; Chong, Peter Han Joo; Law, Wing-Cheung; Chen, Chih-Kuang; Yong, Ken-Tye

    2016-04-01

    First-line therapy of chronic myelogenous leukemia (CML) has always involved the use of BCR-ABL tyrosine-kinase inhibitors which is associated with an abnormal chromosome called Philadelphia chromosome. Although the overall survival rate has been improved by the current therapeutic regime, the presence of resistance has resulted in limited efficacy. In this study, an RNA interference (RNAi)-based therapeutic regime is proposed with the aim to knockdown the BCR-ABL hybrid oncogene using small interfering RNA (siRNA). The siRNA transfection rates have usually been limited due to the declining contact probability among polyplexes and the non-adherent nature of leukemic cells. Our work aims at addressing this limitation by using a biodegradable charged polyester-based vector (BCPV) as a nanocarrier for the delivery of BCR-ABL-specific siRNA to the suspension culture of a K562 CML cell line. BCR-ABL siRNAs were encapsulated in the BCPVs by electrostatic force. Cell internalization was facilitated by the BCPV and assessed by confocal microscopy and flow cytometry. The regulation of the BCR-ABL level in K562 cells as a result of RNAi was analyzed by real-time polymerase chain reaction (RT-PCR). We observed that BCPV was able to form stable nanoplexes with siRNA molecules, even in the presence of fetal bovine serum (FBS), and successfully assisted in vitro siRNA transfection in the non-adherent K562 cells. As a consequence of downregulation of BCR-ABL, BCPV-siRNA nanoplexes inhibited cell proliferation and promoted cell apoptosis. All results were compared with a commercial transfection reagent, Lipofectamine2000™, which served as a positive control. More importantly, this class of non-viral vector exhibits biodegradable features and negligible cytotoxicity, thus providing a versatile platform to deliver siRNA to non-adherent leukemia cells with high transfection efficiency by effectively overcoming extra- and intra-cellular barriers. Due to the excellent in vitro

  6. a positive control plasmid for reporter gene assay

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-04

    Jul 4, 2008 ... qualification as a positive control for luciferase reporter gene assays. Key words: Reporter gene plasmid, luciferase assay, cytomegalovirus promoter/enhancer, human melanoma cell line. INTRODUCTION. Reporter genes, often called reporters, have become a precious tool in studies of gene expression ...

  7. Downstream reporter gene imaging for signal transduction pathway of dopamine type 2 receptor

    International Nuclear Information System (INIS)

    Le, Uyenchi N.; Min, Jung Joon; Moon, Sung Min; Bom, Hee Seung

    2004-01-01

    The Dopamine 2 receptor (D2R) signal pathway regulates gene expression by phosphorylation of proteins including cAMP reponse element-binding protein (CREB), a transcription factor. In this study, we developed a reporter strategy using the GAL4 fusion CREB to assess the phosphorylation of CREB, one of the targets of the D2R signal transduction pathway. We used three plasmids: GAL4 fusion transactivator (pCMV-CREB), firefly luciferase reporter with GAL4 binding sites (pG5-FLUC), and D2R plasmid (pCMV-D2R). Group 1 293T cells were transiently transfected with pCMV-CREB and pG5-FLUC, and group 2 cells were transfected with all three plasmids. Transfected cells were stimulated with different concentrations of dopamine (0-200 M). For animal studies, group 1 and 2 cells (1x10 6 ) were subcutaneously injected on the left and right thigh of six nude mice, respectively. Dopamine stimiulation was performed with intraperitoneal injection of L-DOPA incombination with carbidopa, a peripheral DOPA decarboxylase inhibitor. Bioluminescence optical imaging studies were performed before and after L-DOPA injection. In cell culture studies, group 1 cells showed strong luciferase activity which implies direct activation of the signaling pathway due to growth factors contained in culture medium. Group 2 cells showed strong luciferase activity and a further increase after administration of dopamine. In animal studies, group 1 and 2 cells showed bioluminescence signal before L-DOPA injection, but signal from group 2 cells significantly increased 12 h after L-DOPA injection. The signal from group 1 cells disappeared thereafter, but group 2 cells continued to show signal until 36 h of L-DOPA injection. This study demonstrates imaging of the D2R signal transduction pathway and should be useful for noninvasive imaging of downstream effects of G-coupled protein pathways

  8. Effects of Epigenetic Modulation on Reporter Gene Expression: Implications for Stem Cell Imaging

    Science.gov (United States)

    Krishnan, Manickam; Park, Jinha M.; Cao, Feng; Wang, Dongxu; Paulmurugan, Ramasay; Tseng, Jeffrey R.; Gonzalgo, Mark L.; Gambhir, Sanjiv S.; Wu, Joseph C.

    2013-01-01

    Tracking stem cell localization, survival, differentiation, and proliferation following transplantation in living subjects is essential for understanding stem cell biology and physiology. In this study, we investigated the long-term stability of reporter gene expression in an embryonic rat cardiomyoblast cell line and the role of epigenetic modulation on reversing reporter gene silencing. Cells were stably transfected with plasmids carrying cytomegalovirus promoter driving firefly luciferase reporter gene (CMV-Fluc) and passaged repeatedly for 3–8 months. Within the highest expressor clone, the firefly luciferase activity decreased progressively from passage-1 (843±28) to passage-20 (250±10) to passage-40 (44±3) to passage-60 (3±1 RLU/µg) (P<0.05 vs. passage-1). Firefly luciferase activity was maximally rescued by treatment with 5-azacytidine (DNA methyltransferase inhibitor) compared to trichostatin A (histone deacetylase inhibitor) and retinoic acid (transcriptional activator) (P<0.05). Increasing dosages of 5-azacytidine treatment led to higher levels of firefly luciferase mRNA (RT-PCR) and protein (Western blots) and inversely lower levels of methylation in the CMV promoter (DNA nucleotide sequence). These in vitro results were extended to in vivo bioluminescence imaging (BLI) of cell transplant in living animals. Cells treated with 5-azacytidine were monitored for 2 weeks compared to 1 week for untreated cells (P<0.05). These findings should have important implications for reporter gene-based imaging of stem cell transplantation. PMID:16246867

  9. A nonviral DNA delivery system based on surface modified silica-nanoparticles can efficiently transfect cells in vitro

    NARCIS (Netherlands)

    Kneuer, C; Sameti, M; Bakowsky, U; Schiestel, T; Schirra, H

    2000-01-01

    Diverse polycationic polymers have been used as nonviral transfection agents. Here we report the ability of colloidal silica particles with covalently attached cationic surface modifications to transfect plasmid DNA in vitro and make an attempt to describe the structure of the resulting transfection

  10. [Myocardial single photon emission tomography imaging of reporter gene expression in rabbits].

    Science.gov (United States)

    Liu, Ying; Lan, Xiao-li; Zhang, Liang; Wu, Tao; Jiang, Ri-feng; Zhang, Yong-xue

    2009-06-01

    To explore the feasibility of single photon emission computed tomography (SPECT) detection of heart reporter gene expression and observed the optimal transfecting titer and imaging time by using herpes simplex virus 1-thymidine kinase (HSV1-tk) as reporter gene and 131I-2'-fluoro-2'-deoxy-1-beta-D-arabinofuranosyl-5-iodouracil (131I-FIAU) as reporter probe in rabbit myocardium. The recombinant Ad-tk carrying HSV1-tk gene and adenovirus (Ad) as vector was constructed and intramyocardially injected to rabbits at various concentrations (1 x 10(9) pfu, 5 x 10(8) pfu, 1 x 10(8) pfu, 5 x 10(7) pfu, 1 x 10(7) pfu). Two days later, rabbits were injected with 600 microCi 131I-FIAU in ear-margin vein and then underwent SPECT myocardium imaging for detection of HSV1-tk expression at 6 h, 24 h, 48 h and 72 h after injection, rabbits with 1 x 10(9) pfu Ad-tk injection were imaged at 96 h and 120 h. Rabbits were sacrificed after imaging and the total myocardial 131I-FIAU accumulation was quantified in percent of injected dose per gram myocardium (% ID/g). The myocardial Ad-tk expression was determined with RT-PCR. Reporter gene was detected by SPECT imaging in the injection site while not detected in the control myocardium and site remote from injection. RT-PCR results also evidenced HSV1-tk express in the injection site. The SPECT target/nontarget ratio was correlated with ex vivo gamma-counting (r2 = 0.933, Ppfu by SPECT imaging. The cardiac SPECT reporter gene imaging with HSV1-tk as reporter gene and 131I-FIAU as reporter probe is feasible.

  11. Transfection in Primary Cultured Neuronal Cells.

    Science.gov (United States)

    Marwick, Katie F M; Hardingham, Giles E

    2017-01-01

    Transfection allows the introduction of foreign nucleic acid into eukaryotic cells. It is an important tool in understanding the roles of NMDARs in neurons. Here, we describe using lipofection-mediated transfection to introduce cDNA encoding NMDAR subunits into postmitotic rodent primary cortical neurons maintained in culture.

  12. Transfection of Primary Human Skin Fibroblasts for Peroxisomal Studies

    NARCIS (Netherlands)

    Koster, Janet; Waterham, Hans R.

    2017-01-01

    Functional studies with primary human skin fibroblasts from patients with a peroxisomal disorder often require efficient transfection with plasmids to correct the genetic defect or to express heterologous reporter proteins. Here, we describe a protocol we commonly use for efficient nonviral

  13. Optical sorting and photo-transfection of mammalian cells

    CSIR Research Space (South Africa)

    Mthunzi, P

    2010-02-01

    Full Text Available and that the scattering force can enable sorting through axial guiding onto laminin coated glass coverslips upon which the selected cells adhere. Following this, I report on transient photo-transfection of mammalian cells including neuroblastomas (rat/mouse and human...

  14. Transfection of normal human and Chinese hamster DNA corrects diepoxybutane-induced chromosomal hypersensitivity of Fanconi anemia fibroblasts

    International Nuclear Information System (INIS)

    Shaham, M.; Adler, B.; Ganguly, S.; Chaganti, R.S.K.

    1987-01-01

    Cultured cells from individuals affected with Fanconi anemia (FA) exhibit spontaneous chromosome breakage and hypersensitivity to the cell killing and clastogenic effects of the difunctional alkylating agent diepoxybutane (DEB). The authors report here the correction of both of these DEB-hypersensitivity phenotypes of FA cells achieved by cotransfection of normal placental of Chinese hamster lung cell DNA and the plasmid pSV2-neo-SVgpt. Transfectants were selected for clonogenic survival after treatment with DEB at a dose of 5 μgml. At this dose of DEB, the clonogenicity of normal fibroblasts was reduced to 50% and that of FA fibroblasts was reduced to zero. DEB-resistant (DEB/sup r/) colonies selected in this system exhibited a normal response to DEB-induced chromosome breakage and resistance to repeated DEB treatment. The neo and gpt sequences were detected by Southern blot analysis of DNA from one of four DEB/sup r/ colonies independently derived from transfection of human DNA and one of three DEB/sup r/ colonies independently derived from transfection of Chinese hamster DNA. The results demonstrate that DNA sequences that complement the two hallmark cellular phenotypes (cellular and chromosomal hypersensitivity to alkylating agents) of FA are present in human as well as Chinese hamster DNA. The cloning of these genes using transfection strategies can be expected to enable molecular characterization of FA

  15. A nonviral DNA delivery system based on surface modified silica-nanoparticles can efficiently transfect cells in vitro.

    Science.gov (United States)

    Kneuer, C; Sameti, M; Bakowsky, U; Schiestel, T; Schirra, H; Schmidt, H; Lehr, C M

    2000-01-01

    Diverse polycationic polymers have been used as nonviral transfection agents. Here we report the ability of colloidal silica particles with covalently attached cationic surface modifications to transfect plasmid DNA in vitro and make an attempt to describe the structure of the resulting transfection complexes. In analogy to the terms lipoplex and polyplex, we propose to describe the nanoparticle-DNA complexes by the term "nanoplex". Three batches, Si10E, Si100E, and Si26H, sized between 10 and 100 nm and with zeta potentials ranging from +7 to +31 mV at pH 7.4 were evaluated. The galactosidase expression plasmid DNA pCMVbeta was immobilized on the particle surface and efficiently transfected Cos-1 cells. The transfection activity was accompanied by very low cytotoxicity, with LD(50) values in the milligrams per milliliter range. The most active batch, Si26H, was produced by modification of commercially available silica particles with N-(6-aminohexyl)-3-aminopropyltrimethoxysilane, yielding spherical nanoparticles with a mean diameter of 26 nm and a zeta potential of +31 mV at pH 7.4. Complexes of Si26H and pCMVbeta plasmid DNA formed at w/w ratios of 10 were most effective in promoting transfection of Cos-1 cells in the absence of serum. At this ratio, >90% of the DNA was associated with the particles, yielding nanoplexes with a net negative surface charge. When the transfection medium was supplemented with 10% serum, maximum gene expression was observed at a w/w ratio of 30, at which the resulting particle-DNA complexes possessed a positive surface charge. Transfection was strongly increased in the presence of 100 microM chloroquine in the incubation medium and reached approximately 30% of the efficiency of a 60 kDa polyethylenimine. In contrast to polyethylenimine, no toxicity was observed at the concentrations required. Atomic force microscopy of Si26H-DNA complexes revealed a spaghetti-meatball-like structure. The surface of complexes prepared at a w/w ratio of

  16. Cyclin B1 Destruction Box-Mediated Protein Instability: The Enhanced Sensitivity of Fluorescent-Protein-Based Reporter Gene System

    Directory of Open Access Journals (Sweden)

    Chao-Hsun Yang

    2013-01-01

    Full Text Available The periodic expression and destruction of several cyclins are the most important steps for the exact regulation of cell cycle. Cyclins are degraded by the ubiquitin-proteasome system during cell cycle. Besides, a short sequence near the N-terminal of cyclin B called the destruction box (D-box; CDB is also required. Fluorescent-protein-based reporter gene system is insensitive to analysis because of the overly stable fluorescent proteins. Therefore, in this study, we use human CDB fused with both enhanced green fluorescent protein (EGFP at C-terminus and red fluorescent protein (RFP, DsRed at N-terminus in the transfected human melanoma cells to examine the effects of CDB on different fluorescent proteins. Our results indicated that CDB-fused fluorescent protein can be used to examine the slight gene regulations in the reporter gene system and have the potential to be the system for screening of functional compounds in the future.

  17. COBRA1 inhibits AP-1 transcriptional activity in transfected cells

    International Nuclear Information System (INIS)

    Zhong Hongjun; Zhu Jianhua; Zhang Hao; Ding Lihua; Sun Yan; Huang Cuifen; Ye Qinong

    2004-01-01

    Mutations in the breast cancer susceptibility gene (BRCA1) account for a significant proportion of hereditary breast and ovarian cancers. Cofactor of BRCA1 (COBRA1) was isolated as a BRCA1-interacting protein and exhibited a similar chromatin reorganizing activity to that of BRCA1. However, the biological role of COBRA1 remains largely unexplored. Here, we report that ectopic expression of COBRA1 inhibited activator protein 1 (AP-1) transcriptional activity in transfected cells in a dose-dependent manner, whereas reduction of endogenous COBRA1 with a small interfering RNA significantly enhanced AP-1-mediated transcriptional activation. COBRA1 physically interacted with the AP-1 family members, c-Jun and c-Fos, and the middle region of COBRA1 bound to c-Fos. Lack of c-Fos binding site in the COBRA1 completely abolished the COBRA1 inhibition of AP-1 trans-activation. These findings suggest that COBRA1 may directly modulate AP-1 pathway and, therefore, may play important roles in cell proliferation, differentiation, apoptosis, and oncogenesis

  18. Characterization of cell lines stably transfected with rubella virus replicons

    International Nuclear Information System (INIS)

    Tzeng, Wen-Pin; Xu, Jie; Frey, Teryl K.

    2012-01-01

    Rubella virus (RUBV) replicons expressing a drug resistance gene and a gene of interest were used to select cell lines uniformly harboring the replicon. Replicons expressing GFP and a virus capsid protein GFP fusion (C-GFP) were compared. Vero or BHK cells transfected with either replicon survived drug selection and grew into a monolayer. However, survival was ∼9-fold greater following transfection with the C-GFP-replicon than with the GFP-expressing replicon and while the C-GFP-replicon cells grew similarly to non-transfected cells, the GFP-replicon cells grew slower. Neither was due to the ability of the CP to enhance RNA synthesis but survival during drug selection was correlated with the ability of CP to inhibit apoptosis. Additionally, C-GFP-replicon cells were not cured of the replicon in the absence of drug selection. Interferon-alpha suppressed replicon RNA and protein synthesis, but did not cure the cells, explaining in part the ability of RUBV to establish persistent infections.

  19. Characterization of cell lines stably transfected with rubella virus replicons

    Energy Technology Data Exchange (ETDEWEB)

    Tzeng, Wen-Pin; Xu, Jie [Department of Biology, Georgia State University, P.O. Box 4010, Atlanta GA 30302-4010 (United States); Frey, Teryl K., E-mail: tfrey@gsu.edu [Department of Biology, Georgia State University, P.O. Box 4010, Atlanta GA 30302-4010 (United States)

    2012-07-20

    Rubella virus (RUBV) replicons expressing a drug resistance gene and a gene of interest were used to select cell lines uniformly harboring the replicon. Replicons expressing GFP and a virus capsid protein GFP fusion (C-GFP) were compared. Vero or BHK cells transfected with either replicon survived drug selection and grew into a monolayer. However, survival was {approx}9-fold greater following transfection with the C-GFP-replicon than with the GFP-expressing replicon and while the C-GFP-replicon cells grew similarly to non-transfected cells, the GFP-replicon cells grew slower. Neither was due to the ability of the CP to enhance RNA synthesis but survival during drug selection was correlated with the ability of CP to inhibit apoptosis. Additionally, C-GFP-replicon cells were not cured of the replicon in the absence of drug selection. Interferon-alpha suppressed replicon RNA and protein synthesis, but did not cure the cells, explaining in part the ability of RUBV to establish persistent infections.

  20. Spatial and Temporal Control of Cavitation Allows High In Vitro Transfection Efficiency in the Absence of Transfection Reagents or Contrast Agents

    Science.gov (United States)

    Chettab, Kamel; Roux, Stéphanie; Mathé, Doriane; Cros-Perrial, Emeline; Lafond, Maxime; Lafon, Cyril; Dumontet, Charles; Mestas, Jean-Louis

    2015-01-01

    Sonoporation using low-frequency high-pressure ultrasound (US) is a non-viral approach for in vitro and in vivo gene delivery. In this study, we developed a new sonoporation device designed for spatial and temporal control of ultrasound cavitation. The regulation system incorporated in the device allowed a real-time control of the cavitation level during sonoporation. This device was evaluated for the in vitro transfection efficiency of a plasmid coding for Green Fluorescent Protein (pEGFP-C1) in adherent and non-adherent cell lines. The transfection efficiency of the device was compared to those observed with lipofection and nucleofection methods. In both adherent and non-adherent cell lines, the sonoporation device allowed high rate of transfection of pEGFP-C1 (40–80%), as determined by flow cytometry analysis of GFP expression, along with a low rate of mortality assessed by propidium iodide staining. The transfection efficiency and toxicity of sonoporation on the non-adherent cell lines Jurkat and K562 were similar to those of nucleofection, while these two cell lines were resistant to transfection by lipofection. Moreover, sonoporation was used to produce three stably transfected human lymphoma and leukemia lines. Significant transfection efficiency was also observed in two fresh samples of human acute myeloid leukemia cells. In conclusion, we developed a user-friendly and cost-effective ultrasound device, well adapted for routine in vitro high-yield transfection experiments and which does not require the use of any transfection reagent or gas micro-bubbles. PMID:26274324

  1. Spatial and Temporal Control of Cavitation Allows High In Vitro Transfection Efficiency in the Absence of Transfection Reagents or Contrast Agents.

    Science.gov (United States)

    Chettab, Kamel; Roux, Stéphanie; Mathé, Doriane; Cros-Perrial, Emeline; Lafond, Maxime; Lafon, Cyril; Dumontet, Charles; Mestas, Jean-Louis

    2015-01-01

    Sonoporation using low-frequency high-pressure ultrasound (US) is a non-viral approach for in vitro and in vivo gene delivery. In this study, we developed a new sonoporation device designed for spatial and temporal control of ultrasound cavitation. The regulation system incorporated in the device allowed a real-time control of the cavitation level during sonoporation. This device was evaluated for the in vitro transfection efficiency of a plasmid coding for Green Fluorescent Protein (pEGFP-C1) in adherent and non-adherent cell lines. The transfection efficiency of the device was compared to those observed with lipofection and nucleofection methods. In both adherent and non-adherent cell lines, the sonoporation device allowed high rate of transfection of pEGFP-C1 (40-80%), as determined by flow cytometry analysis of GFP expression, along with a low rate of mortality assessed by propidium iodide staining. The transfection efficiency and toxicity of sonoporation on the non-adherent cell lines Jurkat and K562 were similar to those of nucleofection, while these two cell lines were resistant to transfection by lipofection. Moreover, sonoporation was used to produce three stably transfected human lymphoma and leukemia lines. Significant transfection efficiency was also observed in two fresh samples of human acute myeloid leukemia cells. In conclusion, we developed a user-friendly and cost-effective ultrasound device, well adapted for routine in vitro high-yield transfection experiments and which does not require the use of any transfection reagent or gas micro-bubbles.

  2. Spatial and Temporal Control of Cavitation Allows High In Vitro Transfection Efficiency in the Absence of Transfection Reagents or Contrast Agents.

    Directory of Open Access Journals (Sweden)

    Kamel Chettab

    Full Text Available Sonoporation using low-frequency high-pressure ultrasound (US is a non-viral approach for in vitro and in vivo gene delivery. In this study, we developed a new sonoporation device designed for spatial and temporal control of ultrasound cavitation. The regulation system incorporated in the device allowed a real-time control of the cavitation level during sonoporation. This device was evaluated for the in vitro transfection efficiency of a plasmid coding for Green Fluorescent Protein (pEGFP-C1 in adherent and non-adherent cell lines. The transfection efficiency of the device was compared to those observed with lipofection and nucleofection methods. In both adherent and non-adherent cell lines, the sonoporation device allowed high rate of transfection of pEGFP-C1 (40-80%, as determined by flow cytometry analysis of GFP expression, along with a low rate of mortality assessed by propidium iodide staining. The transfection efficiency and toxicity of sonoporation on the non-adherent cell lines Jurkat and K562 were similar to those of nucleofection, while these two cell lines were resistant to transfection by lipofection. Moreover, sonoporation was used to produce three stably transfected human lymphoma and leukemia lines. Significant transfection efficiency was also observed in two fresh samples of human acute myeloid leukemia cells. In conclusion, we developed a user-friendly and cost-effective ultrasound device, well adapted for routine in vitro high-yield transfection experiments and which does not require the use of any transfection reagent or gas micro-bubbles.

  3. Optical transfection using an endoscope-like system.

    Science.gov (United States)

    Ma, Nan; Gunn-Moore, Frank; Dholakia, Kishan

    2011-02-01

    Optical transfection is a powerful method for targeted delivery of therapeutic agents to biological cells. A tightly focused pulsed laser beam may transiently change the permeability of a cell membrane to facilitate the delivery of foreign genetic material into cells. We report the first realization of an endoscope-like integrated system for optical transfection. An imaging fiber (coherent optical fiber bundle) with ∼ 6000 cores (pixels) embedded in a fiber cladding of ∼ 300 μm in diameter, produces an image circle (area) of ∼ 270 μm diam. This imaging fiber, with an ordered axicon lens array chemically etched at its exit face, is used for the delivery of a femtosecond laser to the cell membrane for optical transfection along with subcellular resolution imaging. A microcapillary-based microfluidic system for localized drug delivery was also combined in this miniature, flexible system. Using this novel system, a plasmid transfection efficiency up to ∼ 72% was obtained for CHO-K1 cells. This endoscope-like system opens a range of exciting applications, in particular, in the targeted in vivo optical microsurgery area.

  4. Anchoring cationic amphiphiles for nucleotide delivery: significance of DNA release from cationic liposomes for transfection.

    Science.gov (United States)

    Hirashima, Naohide; Minatani, Kazuhiro; Hattori, Yoshifumi; Ohwada, Tomohiko; Nakanishi, Mamoru

    2007-06-01

    We have designed and synthesized lithocholic acid-based cationic amphiphile molecules as components of cationic liposomes for gene transfection (lipofection). To study the relationship between the molecular structures of those amphiphilic molecules, particularly the extended hydrophobic appendant (anchor) at the 3-hydroxyl group, and transfection efficiency, we synthesized several lithocholic and isolithocholic acid derivatives, and examined their transfection efficiency. We also compared the physico-chemical properties of cationic liposomes prepared from these derivatives. We found that isolithocholic acid derivatives exhibit higher transfection efficiency than the corresponding lithocholic acid derivatives. This result indicates that the orientation and extension of hydrophobic regions influence the gene transfection process. Isolithocholic acid derivatives showed a high ability to encapsulate DNA in a compact liposome-DNA complex and to protect it from enzymatic degradation. Isolithocholic acid derivatives also facilitated the release of DNA from the liposome-DNA complex, which is a crucial step for DNA entry into the nucleus. Our results show that the transfection efficiency is directly influenced by the ability of the liposome complex to release DNA, rather than by the DNA-encapsulating ability. Molecular modeling revealed that isolithocholic acid derivatives take relatively extended conformations, while the lithocholic acid derivatives take folded structures. Thus, the efficiency of release of DNA from cationic liposomes in the cytoplasm, which contributes to high transfection efficiency, appears to be dependent upon the molecular shape of the cationic amphiphiles.

  5. In Vivo Imaging of Retinoic Acid Receptor Activity using a Sodium/Iodide Symporter and Luciferase Dual Imaging Reporter Gene

    Directory of Open Access Journals (Sweden)

    Min Kyung So

    2004-07-01

    Full Text Available Retinoic acids are natural derivatives of vitamin A, and play important roles in modulating tumor cell growth by regulating differentiation, thus suggesting the potential use of these derivatives in cancer therapy and prevention. To visualize the intranuclear responses of functional retinoic acid receptors, we have developed a dual-imaging reporter gene system based on the use of sodium/iodide symporter (NIS and luciferase in cancer cell lines. NIS and luciferase genes were linked with an internal ribosome entry site, and placed under the control of an artificial cis-acting retinoic acid responsive element (pRARE/NL. After retinoic acid treatment, I-125 uptake by pRARE/NL transfected cells was found to have increased by up to about five times that of nontreated cells. The bioluminescence intensity of pRARE/NL transfected cells showed dose-dependency. In vivo luciferase images showed higher intensity in retinoic acid treated SK-RARE/NL tumors, and scintigraphic images of SK-RARE/NL tumors showed increased Tc-99m uptake after retinoic acid treatment. The NIS/luciferase imaging reporter system was sufficiently sensitive to allow the visualization of intranuclear retinoic acid receptor activity. This cis-enhancer imaging reporter system may be useful in vitro and in vivo for the evaluation of retinoic acid responses in such areas as cellular differentiation and chemoprevention.

  6. Reporter gene bioassays in environmental analysis.

    Science.gov (United States)

    Köhler, S; Belkin, S; Schmid, R D

    2000-01-01

    In parallel to the continuous development of increasingly more sophisticated physical and chemical analytical technologies for the detection of environmental pollutants, there is a progressively more urgent need also for bioassays which report not only on the presence of a chemical but also on its bioavailability and its biological effects. As a partial fulfillment of that need, there has been a rapid development of biosensors based on genetically engineered bacteria. Such microorganisms typically combine a promoter-operator, which acts as the sensing element, with reporter gene(s) coding for easily detectable proteins. These sensors have the ability to detect global parameters such as stress conditions, toxicity or DNA-damaging agents as well as specific organic and inorganic compounds. The systems described in this review, designed to detect different groups of target chemicals, vary greatly in their detection limits, specificity, response times and more. These variations reflect on their potential applicability which, for most of the constructs described, is presently rather limited. Nevertheless, present trends promise that additional improvements will make microbial biosensors an important tool for future environmental analysis.

  7. Tripartite polyionic complex (PIC) micelles as non-viral vectors for mesenchymal stem cell siRNA transfection.

    Science.gov (United States)

    Raisin, Sophie; Morille, Marie; Bony, Claire; Noël, Danièle; Devoisselle, Jean-Marie; Belamie, Emmanuel

    2017-08-22

    In the context of regenerative medicine, the use of RNA interference mechanisms has already proven its efficiency in targeting specific gene expression with the aim of enhancing, accelerating or, more generally, directing stem cell differentiation. However, achievement of good transfection levels requires the use of a gene vector. For in vivo applications, synthetic vectors are an interesting option to avoid possible issues associated with viral vectors (safety, production costs, etc.). Herein, we report on the design of tripartite polyionic complex micelles as original non-viral polymeric vectors suited for mesenchymal stem cell transfection with siRNA. Three micelle formulations were designed to exhibit pH-triggered disassembly in an acidic pH range comparable to that of endosomes. One formulation was selected as the most promising with the highest siRNA loading capacity while clearly maintaining pH-triggered disassembly properties. A thorough investigation of the internalization pathway of micelles into cells with tagged siRNA was made before showing an efficient inhibition of Runx2 expression in primary bone marrow-derived stem cells. This work evidenced PIC micelles as promising synthetic vectors that allow efficient MSC transfection and control over their behavior, from the perspective of their clinical use.

  8. Transfection effect of microbubbles on cells in superposed ultrasound waves and behavior of cavitation bubble.

    Science.gov (United States)

    Kodama, Tetsuya; Tomita, Yukio; Koshiyama, Ken-Ichiro; Blomley, Martin J K

    2006-06-01

    The combination of ultrasound and ultrasound contrast agents (UCAs) is able to induce transient membrane permeability leading to direct delivery of exogenous molecules into cells. Cavitation bubbles are believed to be involved in the membrane permeability; however, the detailed mechanism is still unknown. In the present study, the effects of ultrasound and the UCAs, Optison on transfection in vitro for different medium heights and the related dynamic behaviors of cavitation bubbles were investigated. Cultured CHO-E cells mixed with reporter genes (luciferase or beta-gal plasmid DNA) and UCAs were exposed to 1 MHz ultrasound in 24-well plates. Ultrasound was applied from the bottom of the well and reflected at the free surface of the medium, resulting in the superposition of ultrasound waves within the well. Cells cultured on the bottom of 24-well plates were located near the first node (displacement node) of the incident ultrasound downstream. Transfection activity was a function determined with the height of the medium (wave traveling distance), as well as the concentration of UCAs and the exposure time was also determined with the concentration of UCAs and the exposure duration. Survival fraction was determined by MTT assay, also changes with these values in the reverse pattern compared with luciferase activity. With shallow medium height, high transfection efficacy and high survival fraction were obtained at a low concentration of UCAs. In addition, capillary waves and subsequent atomized particles became significant as the medium height decreased. These phenomena suggested cavitation bubbles were being generated in the medium. To determine the effect of UCAs on bubble generation, we repeated the experiments using crushed heat-treated Optison solution instead of the standard microbubble preparation. The transfection ratio and survival fraction showed no additional benefit when ultrasound was used. These results suggested that cavitation bubbles created by the

  9. MR molecular imaging of tumours using ferritin heavy chain reporter gene expression mediated by the hTERT promoter

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yan [Third Military Medical University, Department of Radiology, XinQiao Hospital, ChongQing (China); The First Affiliated Hospital of ChengDu Medical College, Department of Radiology, ChengDu (China); Gong, Ming-fu; Yang, Hua; Zhang, Song; Wang, Guang-xian; Su, Tong-sheng; Wen, Li; Zhang, Dong [Third Military Medical University, Department of Radiology, XinQiao Hospital, ChongQing (China)

    2016-11-15

    Using the human telomerase reverse transcriptase (hTERT) promoter and the modified ferritin heavy chain (Fth) reporter gene, reporter gene expression for MRI was examined in telomerase positive and negative tumour cells and xenografts. Activity of the reporter gene expression vector Lenti-hTERT-Fth1-3FLAG-Puro was compared to constitutive CMV-driven expression and to the untransfected parental control in five tumour cell lines: A549, SKOV3, 293T, U2OS and HPDLF. In vitro, transfected cells were evaluated for FLAG-tagged protein expression, iron accumulation and transverse relaxation. In vivo, tumours transduced by lentiviral vector injection were imaged using T2*WI. Changes in tumour signal intensity were validated by histology. Only telomerase positive tumour cells expressed FLAG-tagged Fth and displayed an increase in R2* above the parental control, with a corresponding change in T2*WI. In addition, only telomerase positive tumours, transduced by injection of the reporter gene expression construct, exhibited a change in signal intensity on T2*WI. Tumour histology verified the expression of FLAG-tagged Fth and iron accumulation in telomerase positive tissue. Reporter gene expression for MRI, using the Fth reporter and the hTERT promoter, may be a useful strategy for the non-invasive diagnosis of many types of cancer. (orig.)

  10. Study of rNIS as a reporter gene monitoring rBMSC transplanted to rat myocardium

    International Nuclear Information System (INIS)

    Hu Shou; Lan Xiaoli; Cao Wei; Cao Guoxiang; Zhang Guopeng; Zhang Binqing; Wu Tao; Chang Wei; Zhang Yongxue

    2010-01-01

    Objective: To investigate the feasibility of rat sodium/iodide symporter (rNIS) as a reporter gene monitoring rat bone marrow mesenchymal cells (rBMSC) transplanted to rat myocardium in vivo. Methods: Recombinated adenovirus vector was constructed by rNIS/enhanced green fluorescence protein (EGFP) (Ad-rNIS/EGFP). rBMSC transfected by Ad-rNIS/EGFP were studied using fluorescence microscope. Fifteen rats were transplanted with rBMSC and randomly divided into three groups: rNIS group (with rNIS transfection), blocked group (with rNIS transfection) by oral intake of perchloric sodium before planar imaging (GE Millennium MPR SPECT), and control group (without rNIS transfection). All rats underwent 99 Tc m -pertechnetate planar imaging. The biological distribution of 99 Tc m -pertechnetate was studied. The expressions of rNIS gene and protein in myocardium were measured by real time polymerase chain reaction (PCR) and western blot, respectively. The expressions of CD 29 , CD 44 , CD 90 , CD 11 b, CD 34 and CD 45 were measured by immunohistochemistry. Results: rBMSC transfected by Ad-rNIS/EGFP showed EGFP expression under fluorescence microscope. The transplanted rat myocardium could be visualized on 99 Tc m -pertechnetate planar imaging in rNIS group. The relative uptake ratio (R heart /R hmb , RUR) was 6.7 ±0.4. RUR in control group (3.0 ±0.2) was lower than that in rNIS group (t =2.78, P=0.03). The percentage injection dose per gram of tissue (% ID/g) of the transplanted myocardium was 60.2 ± 20.8 in rNIS group, which was higher than that (2.5 ± 0.4) % ID/g of control group ( t = 7.13, P 29 , CD 44 and CD 90 were positive, CD 45 and CD 45 negative CD 11 b mildly positive in the myocardium transplanted with infective rBMSC. Conclusion: rNIS can efficiently monitor rBMSC transplanted to rat myocardium. (authors)

  11. Protocol for Lipid-Mediated Transient Transfection in A549 Epithelial Lung Cell Line.

    Science.gov (United States)

    Marcos-Vadillo, Elena; García-Sánchez, Asunción

    2016-01-01

    Trials of transfection in eukaryotic cells are essential tools for the study of gene and protein function. They have been used in a wide range of research fields. In this chapter, a method of transient transfection of the A549 cell line, human lung cells of alveolar epithelium, with an expression plasmid is described. In addition, the fundamental characteristics of this experimental procedure are addressed.

  12. Protein-free transfection of CHO host cells with an IgG-fusion protein: selection and characterization of stable high producers and comparison to conventionally transfected clones.

    Science.gov (United States)

    Lattenmayer, Christine; Loeschel, Martina; Schriebl, Kornelia; Steinfellner, Willibald; Sterovsky, Thomas; Trummer, Evelyn; Vorauer-Uhl, Karola; Müller, Dethardt; Katinger, Hermann; Kunert, Renate

    2007-04-15

    In order to improve the current techniques of cell cultivation in the absence of serum, we have developed a protein-free transfection protocol for CHO cells, based on the Nucleofector technology. After starting with a heterogeneous pool of primary transfectants which express the fusion protein EpoFc, we isolated single clones and compared them with parallel clones generated by lipofection in serum-dependent cultivation. Our intensive characterization program was based on determination of specific productivity (q(p)) and analysis of genetic parameters. In two nucleofection experiments, transfection with 5 microg of DNA resulted in best productivities of the primary cell pools. After subcloning, the q(p) could be raised up to 27 pg x cells(-1) x day(-1). While the serum-dependent transfectants exhibited specific productivities up to 57 pg x cells(-1) x day(-1) in serum-dependent cultivation, a significant decrease that resulted in the range of q(p) of the protein-free transfectants was observed after switching to protein-free conditions. Investigation of genetic parameters revealed higher mRNA levels and gene copy numbers (GCN) for the protein-free adapted serum-dependent transfectants. Therefore, we assume that problems during protein-free adaptation (PFA) lead to a less efficient translation machinery after serum deprivation. We describe the generation of stable-producing recombinant CHO clones by protein-free transfection of a protein-free adapted host cell line, which reduces the risk of adverse clonal changes after PFA. The main advantage of this approach is the earlier predictability of clone behavior, which makes the generation of production clones by protein-free transfection, a viable and highly efficient strategy for recombinant cell line development. (c) 2006 Wiley Periodicals, Inc.

  13. Developmentally regulated expression of reporter gene in adult ...

    Indian Academy of Sciences (India)

    pression of reporter gene in adult brain specific GAL4 enhancer traps of. Drosophila ... genes based on their expression pattern, thus enabling us to overcome the ... order association and storage centres of olfactory learning and memory, and ...

  14. Human reporter genes: potential use in clinical studies

    Energy Technology Data Exchange (ETDEWEB)

    Serganova, Inna [Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021 (United States); Ponomarev, Vladimir [Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021 (United States); Blasberg, Ronald [Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021 (United States); Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021 (United States)], E-mail: blasberg@neuro1.mskcc.org

    2007-10-15

    The clinical application of positron-emission-tomography-based reporter gene imaging will expand over the next several years. The translation of reporter gene imaging technology into clinical applications is the focus of this review, with emphasis on the development and use of human reporter genes. Human reporter genes will play an increasingly more important role in this development, and it is likely that one or more reporter systems (human gene and complimentary radiopharmaceutical) will take leading roles. Three classes of human reporter genes are discussed and compared: receptors, transporters and enzymes. Examples of highly expressed cell membrane receptors include specific membrane somatostatin receptors (hSSTrs). The transporter group includes the sodium iodide symporter (hNIS) and the norepinephrine transporter (hNET). The endogenous enzyme classification includes human mitochondrial thymidine kinase 2 (hTK2). In addition, we also discuss the nonhuman dopamine 2 receptor and two viral reporter genes, the wild-type herpes simplex virus 1 thymidine kinase (HSV1-tk) gene and the HSV1-tk mutant (HSV1-sr39tk). Initial applications of reporter gene imaging in patients will be developed within two different clinical disciplines: (a) gene therapy and (b) adoptive cell-based therapies. These studies will benefit from the availability of efficient human reporter systems that can provide critical monitoring information for adenoviral-based, retroviral-based and lenteviral-based gene therapies, oncolytic bacterial and viral therapies, and adoptive cell-based therapies. Translational applications of noninvasive in vivo reporter gene imaging are likely to include: (a) quantitative monitoring of gene therapy vectors for targeting and transduction efficacy in clinical protocols by imaging the location, extent and duration of transgene expression; (b) monitoring of cell trafficking, targeting, replication and activation in adoptive T-cell and stem/progenitor cell therapies

  15. Human reporter genes: potential use in clinical studies

    International Nuclear Information System (INIS)

    Serganova, Inna; Ponomarev, Vladimir; Blasberg, Ronald

    2007-01-01

    The clinical application of positron-emission-tomography-based reporter gene imaging will expand over the next several years. The translation of reporter gene imaging technology into clinical applications is the focus of this review, with emphasis on the development and use of human reporter genes. Human reporter genes will play an increasingly more important role in this development, and it is likely that one or more reporter systems (human gene and complimentary radiopharmaceutical) will take leading roles. Three classes of human reporter genes are discussed and compared: receptors, transporters and enzymes. Examples of highly expressed cell membrane receptors include specific membrane somatostatin receptors (hSSTrs). The transporter group includes the sodium iodide symporter (hNIS) and the norepinephrine transporter (hNET). The endogenous enzyme classification includes human mitochondrial thymidine kinase 2 (hTK2). In addition, we also discuss the nonhuman dopamine 2 receptor and two viral reporter genes, the wild-type herpes simplex virus 1 thymidine kinase (HSV1-tk) gene and the HSV1-tk mutant (HSV1-sr39tk). Initial applications of reporter gene imaging in patients will be developed within two different clinical disciplines: (a) gene therapy and (b) adoptive cell-based therapies. These studies will benefit from the availability of efficient human reporter systems that can provide critical monitoring information for adenoviral-based, retroviral-based and lenteviral-based gene therapies, oncolytic bacterial and viral therapies, and adoptive cell-based therapies. Translational applications of noninvasive in vivo reporter gene imaging are likely to include: (a) quantitative monitoring of gene therapy vectors for targeting and transduction efficacy in clinical protocols by imaging the location, extent and duration of transgene expression; (b) monitoring of cell trafficking, targeting, replication and activation in adoptive T-cell and stem/progenitor cell therapies

  16. Bio-Orthogonal Mediated Nucleic Acid Transfection of Cells via Cell Surface Engineering.

    Science.gov (United States)

    O'Brien, Paul J; Elahipanah, Sina; Rogozhnikov, Dmitry; Yousaf, Muhammad N

    2017-05-24

    The efficient delivery of foreign nucleic acids (transfection) into cells is a critical tool for fundamental biomedical research and a pillar of several biotechnology industries. There are currently three main strategies for transfection including reagent, instrument, and viral based methods. Each technology has significantly advanced cell transfection; however, reagent based methods have captured the majority of the transfection market due to their relatively low cost and ease of use. This general method relies on the efficient packaging of a reagent with nucleic acids to form a stable complex that is subsequently associated and delivered to cells via nonspecific electrostatic targeting. Reagent transfection methods generally use various polyamine cationic type molecules to condense with negatively charged nucleic acids into a highly positively charged complex, which is subsequently delivered to negatively charged cells in culture for association, internalization, release, and expression. Although this appears to be a straightforward procedure, there are several major issues including toxicity, low efficiency, sorting of viable transfected from nontransfected cells, and limited scope of transfectable cell types. Herein, we report a new strategy (SnapFect) for nucleic acid transfection to cells that does not rely on electrostatic interactions but instead uses an integrated approach combining bio-orthogonal liposome fusion, click chemistry, and cell surface engineering. We show that a target cell population is rapidly and efficiently engineered to present a bio-orthogonal functional group on its cell surface through nanoparticle liposome delivery and fusion. A complementary bio-orthogonal nucleic acid complex is then formed and delivered to which chemoselective click chemistry induced transfection occurs to the primed cell. This new strategy requires minimal time, steps, and reagents and leads to superior transfection results for a broad range of cell types

  17. Transfection of genetically encoded photoswitchable probes for STORM imaging.

    Science.gov (United States)

    Bates, Mark; Jones, Sara A; Zhuang, Xiaowei

    2013-06-01

    Conventional fluorescence microscopy is limited by its spatial resolution, leaving many biological structures too small to be studied in detail. Stochastic optical reconstruction microscopy (STORM) is a method for superresolution fluorescence imaging based on the high accuracy localization of individual fluorophores. It uses optically switchable fluorophores: molecules that can be switched between a nonfluorescent and a fluorescent state by exposure to light. This protocol describes the transfection of genetically encoded photoswitchable probes for STORM imaging. It includes a discussion of how to choose a photoswitchable fluorescent protein; standard molecular biology techniques should be used to generate a plasmid containing the sequence of the photoswitchable protein linked to the gene of interest. Once the plasmid has been generated and has been verified, it can be introduced into cells via any standard means of gene delivery, such as lipofection or electroporation. Optimal conditions will vary considerably for different cell lines and plasmids. Here, we present an example protocol for the transfection of BS-C-1 cells with an mEos2-vimentin plasmid using the lipid-based reagent FuGENE6.

  18. Green fluorescent protein as indicator of nonviral transient transfection efficiency in endometrial and testicular biopsies.

    Science.gov (United States)

    Zizzi, Antonio; Minardi, Daniele; Ciavattini, Andrea; Giantomassi, Federica; Montironi, Rodolfo; Muzzonigro, Giovanni; Di Primio, Roberto; Lucarini, Guendalina

    2010-03-01

    In the last years, physical and chemical methods of plasmid delivery have revolutionized the efficiency of nonviral gene transfer, and the success of gene therapy is largely dependent upon the development of gene-delivery methods. The nonviral techniques that lead to a direct transfer of DNA into tissue fragments, like electroporation (EP) and lipofection delivery systems are still insufficiently investigated. Our aim was to test the efficiency of EP and lipofection protocols in endometrial and testicular tissue fragments, using a naked plasmid DNA encoding green fluorescent protein (GFP). Because the transfection efficiency depends upon several factors, we tried to optimize the transfection conditions by testing different lipofectamine 2000 and plasmid ratios, electrical parameters, and culture after transfection. Our results show that these two nonviral methods of gene delivery are feasible and efficient in gene transfection of endometrial and testicular tissue biopsies. We found that the most performing ratio of plasmid:lipofectamine was 10:50 for transient lipofection, whereas two pulses for 10 s at 960 microF of capacitance, 200 V of voltage were the most favorable electrical parameters for EP efficiency in the presence of 5 microL of phMGFP plasmid. After lipofection and EP, the highest GFP intensity was observed respectively after 48 and 72 h of tissue fragment culturing. In conclusion, nonviral methods are attractive for an improvement of the gene therapy and our protocol could provide useful indications for in vivo gene therapy applications.

  19. Thiolated chitosan nanoparticles: transfection study in the Caco-2 differentiated cell culture

    International Nuclear Information System (INIS)

    Martien, Ronny; Loretz, Brigitta; Sandbichler, Adolf Michael; Schnuerch, Andreas Bernkop

    2008-01-01

    The aim of this study was to monitor the expression of secreted protein in differentiated Caco-2 cells after transfection with nanoparticles, in order to improve gene delivery. Based on unmodified chitosan and thiolated chitosan conjugates, nanoparticles with the gene reporter pSEAP (recombinant Secreted Alkaline Phosphatase) were generated at pH 4.0. Transfection studies of thiolated chitosan in Caco-2 cells during the exponential growth phase and differentiation growth phase of the cells led to a 5.0-fold and 2.0-fold increase in protein expression when compared to unmodified chitosan nanoparticles. The mean particle size for both unmodified chitosan and cross-linked thiolated chitosan nanoparticles is 212.2 ± 86 and 113.6 ± 40 nm, respectively. The zeta potential of nanoparticles was determined to be 7.9 ± 0.38 mV for unmodified chitosan nanoparticles and 4.3 ± 0.74 mV for cross-linked thiolated chitosan nanoparticles. Red blood cell lysis evaluation was used to evaluate the membrane damaging properties of unmodified and thiolated chitosan nanoparticles and led to 4.61 ± 0.36% and 2.29 ± 0.25% lysis, respectively. Additionally, cross-linked thiolated chitosan nanoparticles were found to exhibit higher stability toward degradation in gastric juices. Furthermore the reversible effect of thiolated chitosan on barrier properties was monitored by measuring the transepithelial electrical resistance (TEER) and is supported by immunohistochemical staining for the tight junction protein claudin. According to these results cross-linked thiolated chitosan nanoparticles have the potential to be used as a non-viral vector system for gene therapy

  20. Assays for noninvasive imaging of reporter gene expression

    International Nuclear Information System (INIS)

    Gambhir, S.S.; Barrio, J.R.; Herschman, H.R.; Phelps, M.E.

    1999-01-01

    Repeated, noninvasive imaging of reporter gene expression is emerging as a valuable tool for monitoring the expression of genes in animals and humans. Monitoring of organ/cell transplantation in living animals and humans, and the assessment of environmental, behavioral, and pharmacologic modulation of gene expression in transgenic animals should soon be possible. The earliest clinical application is likely to be monitoring human gene therapy in tumors transduced with the herpes simplex virus type 1 thymidine kinase (HSV1-tk) suicide gene. Several candidate assays for imaging reporter gene expression have been studied, utilizing cytosine deaminase (CD), HSV1-tk, and dopamine 2 receptor (D2R) as reporter genes. For the HSV1-tk reporter gene, both uracil nucleoside derivatives (e.g., 5-iodo-2'-fluoro-2'-deoxy-1-β-D-arabinofuranosyl-5-iodouracil [FIAU] labeled with 124 I, 131 I ) and acycloguanosine derivatives {e.g., 8-[ 18 F]fluoro-9-[[2-hydroxy-1-(hydroxymethyl)ethoxy]methyl]guanine (8-[ 18 F]-fluoroganciclovir) ([ 18 F]FGCV), 9-[(3-[ 18 F]fluoro-1-hydroxy-2-propoxy)methyl]guanine ([ 18 F]FHPG)} have been investigated as reporter probes. For the D2R reporter gene, a derivative of spiperone {3-(2'-[ 18 F]-Fluoroethyl)spiperone ([ 18 F]FESP)} has been used with positron emission tomography (PET) imaging. In this review, the principles and specific assays for imaging reporter gene expression are presented and discussed. Specific examples utilizing adenoviral-mediated delivery of a reporter gene as well as tumors expressing reporter genes are discussed

  1. Autoradiography study and SPECT imaging of reporter gene HSV1-tk expression in heart

    Energy Technology Data Exchange (ETDEWEB)

    Lan Xiaoli [Department of Nuclear Medicine, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Hubei Province Key Laboratory of Molecular Imaging, Wuhan, Hubei Province, 430022 (China)], E-mail: LXL730724@hotmail.com; Liu Ying; He Yong; Wu Tao; Zhang Binqing; Gao Zairong; An Rui [Department of Nuclear Medicine, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Hubei Province Key Laboratory of Molecular Imaging, Wuhan, Hubei Province, 430022 (China); Zhang Yongxue [Department of Nuclear Medicine, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Hubei Province Key Laboratory of Molecular Imaging, Wuhan, Hubei Province, 430022 (China)], E-mail: zhyx1229@163.com

    2010-04-15

    Aim: To demonstrate the feasibility and optimal conditions of imaging herpes simplex virus 1-thymidine kinase (HSV1-tk) gene transferred into hearts with {sup 131}I-2'-fluoro-2'-deoxy-1-{beta}-D-arabinofuranosyl-5-iodouracil ({sup 131}I-FIAU) using autoradiography (ARG) and single photon emission computed tomography (SPECT) in animal models. Methods: HSV1-tk inserted into adenovirus vector (Ad5-tk) and adenovirus (Ad5-null) was prepared. Rats or rabbits were divided into a study group receiving intramyocardial injection of Ad5-tk, and a control group receiving Ad-null injection. In the study group of rats, two sets of experiments, time-course study and dose-dependence study, were performed. In time-course experiments, rats were injected with {sup 131}I-FIAU on Days 1, 2, 3, 5 and 7, after transfection of 1x10{sup 8} pfu Ad5-tk, to study the feasibility and suitable time course for reporter gene imaging. In dose-dependence study, various titers of Ad5-tk (5x10{sup 8}, 1x10{sup 8}, 5x10{sup 7} and 1x10{sup 7} pfu) were used to determine the threshold and optimal viral titer needed for detection of gene expression. The gamma counts of hearts were measured. The rat myocardium was analyzed by ARG and reverse transcriptase-polymerase chain reaction (RT-PCR). SPECT whole-body planar imaging and cardiac tomographic imaging were performed in the rabbit models. Results: From the ARG images, rats injected with Ad5-tk showed significant {sup 131}I-FIAU activity in the anterolateral wall compared with background signals seen in the control Ad5-null rats. In time-course study, the highest radioactivity in the focal myocardium could be seen on Day 1, and then progressively declined with time. In dose-dependence study, the level of {sup 131}I-FIAU accumulation in the transfected myocardium declined with the decrease of Ad viral titers. From the ARG analysis and gamma counting, the threshold viral titer was 5x10{sup 7} pfu, and the optimal Ad titer was 1x10{sup 8} pfu

  2. An evolutionary conserved region (ECR in the human dopamine receptor D4 gene supports reporter gene expression in primary cultures derived from the rat cortex

    Directory of Open Access Journals (Sweden)

    Haddley Kate

    2011-05-01

    Full Text Available Abstract Background Detecting functional variants contributing to diversity of behaviour is crucial for dissecting genetics of complex behaviours. At a molecular level, characterisation of variation in exons has been studied as they are easily identified in the current genome annotation although the functional consequences are less well understood; however, it has been difficult to prioritise regions of non-coding DNA in which genetic variation could also have significant functional consequences. Comparison of multiple vertebrate genomes has allowed the identification of non-coding evolutionary conserved regions (ECRs, in which the degree of conservation can be comparable with exonic regions suggesting functional significance. Results We identified ECRs at the dopamine receptor D4 gene locus, an important gene for human behaviours. The most conserved non-coding ECR (D4ECR1 supported high reporter gene expression in primary cultures derived from neonate rat frontal cortex. Computer aided analysis of the sequence of the D4ECR1 indicated the potential transcription factors that could modulate its function. D4ECR1 contained multiple consensus sequences for binding the transcription factor Sp1, a factor previously implicated in DRD4 expression. Co-transfection experiments demonstrated that overexpression of Sp1 significantly decreased the activity of the D4ECR1 in vitro. Conclusion Bioinformatic analysis complemented by functional analysis of the DRD4 gene locus has identified a a strong enhancer that functions in neurons and b a transcription factor that may modulate the function of that enhancer.

  3. Antigen-presenting cells transfected with Hsp65 messenger RNA fail to treat experimental tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, C.D.; Trombone, A.P.F.; Lorenzi, J.C.C.; Almeida, L.P.; Gembre, A.F.; Padilha, E. [Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Ramos, S.G. [Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Silva, C.L.; Coelho-Castelo, A.A.M. [Departamento de Bioquímica e Imunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2012-09-21

    In the last several years, the use of dendritic cells has been studied as a therapeutic strategy against tumors. Dendritic cells can be pulsed with peptides or full-length protein, or they can be transfected with DNA or RNA. However, comparative studies suggest that transfecting dendritic cells with messenger RNA (mRNA) is superior to other antigen-loading techniques in generating immunocompetent dendritic cells. In the present study, we evaluated a new therapeutic strategy to fight tuberculosis using dendritic cells and macrophages transfected with Hsp65 mRNA. First, we demonstrated that antigen-presenting cells transfected with Hsp65 mRNA exhibit a higher level of expression of co-stimulatory molecules, suggesting that Hsp65 mRNA has immunostimulatory properties. We also demonstrated that spleen cells obtained from animals immunized with mock and Hsp65 mRNA-transfected dendritic cells were able to generate a mixed Th1/Th2 response with production not only of IFN-γ but also of IL-5 and IL-10. In contrast, cells recovered from mice immunized with Hsp65 mRNA-transfected macrophages were able to produce only IL-5. When mice were infected with Mycobacterium tuberculosis and treated with antigen-presenting cells transfected with Hsp65 mRNA (therapeutic immunization), we did not detect any decrease in the lung bacterial load or any preservation of the lung parenchyma, indicating the inability of transfected cells to confer curative effects against tuberculosis. In spite of the lack of therapeutic efficacy, this study reports for the first time the use of antigen-presenting cells transfected with mRNA in experimental tuberculosis.

  4. An Evaluation on Transfection Efficiency of pHRE-Egr1-EGFP in Hepatocellular Carcinoma Cells Bel-7402 Mediated by PEI-MZF-NPs

    Directory of Open Access Journals (Sweden)

    Mei Lin

    2011-01-01

    Full Text Available To improve transfection and expression efficiency of target gene, especially under cancer anoxic microenvironment, we have developed pHRE-Egr1-EGFP/PEI-MZF-NPs nanosystem, in which pHRE-Egr1-EGFP, eukaryotic gene expression plasmid, is constructed by combining radiation promoter Egr1 with anoxia induction components (HRE, forming anoxic radiation double sensitive HRE/Egr1 promoter to activate reporter gene EGFP expression. MZF-NPs (Mn0.5 Zn0.5 Fe2O4 magnetic nanoparticles, obtained by coprecipitation method, are coated with cation poly(ethylenimine (PEI. We transferred pHRE-Egr1-EGFP into hepatocellular carcinoma Bel-7402 cells, using PEI-MZF-NPs as the carrier and tested some relevant efficacy. The results show that PEI-MZF-NPs have good DNA-binding ability, protection ability, release ability, little toxicity, and high transfection efficiency, obviously superior to those of the liposome method and electricity perforation method. Moreover, the expression level of EGFP gene induced by anoxia and radiation was significantly higher than that of single radiation activation. It is therefore concluded that HRE/Egr1 can induce and improve target gene expression efficiency in cancer anoxic microenvironment, and that PEI-MZF-NPs can be used as a novel nonviral gene vector which offers a viable approach to the mediated radiation gene therapy of cancer.

  5. Transfection and imaging of diamond nanocrystals as scattering optical labels

    International Nuclear Information System (INIS)

    Smith, Bradley R.; Niebert, Marcus; Plakhotnik, Taras; Zvyagin, Andrei V.

    2007-01-01

    We report on the first demonstration of nanodiamond (ND) as a scattering optical label in a biological environment. NDs were efficiently transfected into cells using cationic liposomes, and imaged using differential interference and Hoffman modulation 'space' contrast microscopy techniques. We have shown that 55 nm NDs are biologically inert and produce a bright signal compared to the cell background. ND as a scattering label presents the possibility for extended biological imaging with relatively little thermal or biochemical perturbations due to the optical transparency and biologically inert nature of diamond

  6. Molecular studies of fibroblasts transfected with hepatitis B virus DNA

    International Nuclear Information System (INIS)

    Chen, M.L.; Hood, A.; Thung, S.N.; Gerber, M.A.

    1987-01-01

    Two subclones (D7 and F8) derived from an NIH 3T3 mouse fibroblast cell line after transfection with hepatitis B virus (HBV) genomes, secreted significantly different amounts of HBsAg and HBeAg. DNA extracted from the subclones revealed only integrated and no extrachromosomal HBV DNA sequences as determined by the Southern blot technique with a /sup 32/P-labeled full length HBV DNA probe. The amount and integration sites of HBV sequences were significantly different in the two subclones. HBV DNA sequences coding for HBsAg and HBcAg were detected by alkaline phosphatase-conjugated, single-stranded synthetic gene-specific oligonucleotide probes revealing a larger number of copies in D7 DNA than in F8 DNA. Using a biotinylated probe for in situ hybridization, HBV DNA was found in the nuclei of all D7 cells with predominant localization to a single chromsome, but only in 10-20% of F8 cells. These observations demonstrate different integration patterns of HBV and DNA in two subclones derived from a transfected cell line and suggest that the amount of integrated HBV DNA is proportional to the amount of HBV antigens produced

  7. Proteome alteration induced by hTERT transfection of human fibroblast cells.

    Science.gov (United States)

    Mazzucchelli, Gabriel D; Gabelica, Valérie; Smargiasso, Nicolas; Fléron, Maximilien; Ashimwe, Wilson; Rosu, Frédéric; De Pauw-Gillet, Marie-Claire; Riou, Jean-François; De Pauw, Edwin

    2008-04-17

    Telomerase confers cellular immortality by elongating telomeres, thereby circumventing the Hayflick limit. Extended-life-span cells have been generated by transfection with the human telomerase reverse transcriptase (hTERT) gene. hTERT transfected cell lines may be of outstanding interest to monitor the effect of drugs targeting the telomerase activity. The incidence of hTERT gene transfection at the proteome level is a prerequisite to that purpose. The effect of the transfection has been studied on the proteome of human fibroblast (WI38). Cytosolic and nuclear fractions of WI38 cells, empty vector transfected WI38 (WI38-HPV) and hTERT WI38 cells were submitted to a 2D-DIGE (Two-Dimensional Differential In-Gel Electrophoresis) analysis. Only spots that had a similar abundance in WI38 and WI38-HPV, but were differentially expressed in WI38 hTERT were selected for MS identification. This method directly points to the proteins linked with the hTERT expression. Number of false positive differentially expressed proteins has been excluded by using control WI38-HPV cells. The proteome alteration induced by hTERT WI38 transfection should be taken into account in subsequent use of the cell line for anti-telomerase drugs evaluation. 2D-DIGE experiment shows that 57 spots out of 2246 are significantly differentially expressed in the cytosolic fraction due to hTERT transfection, and 38 were confidently identified. In the nuclear fraction, 44 spots out of 2172 were selected in the differential proteome analysis, and 14 were identified. The results show that, in addition to elongating telomeres, hTERT gene transfection has other physiological roles, among which an enhanced ER capacity and a potent cell protection against apoptosis. We show that the methodology reduces the complexity of the proteome analysis and highlights proteins implicated in other processes than telomere elongation. hTERT induced proteome changes suggest that telomerase expression enhances natural cell repair

  8. Proteome alteration induced by hTERT transfection of human fibroblast cells

    Directory of Open Access Journals (Sweden)

    Riou Jean-François

    2008-04-01

    Full Text Available Abstract Background Telomerase confers cellular immortality by elongating telomeres, thereby circumventing the Hayflick limit. Extended-life-span cells have been generated by transfection with the human telomerase reverse transcriptase (hTERT gene. hTERT transfected cell lines may be of outstanding interest to monitor the effect of drugs targeting the telomerase activity. The incidence of hTERT gene transfection at the proteome level is a prerequisite to that purpose. The effect of the transfection has been studied on the proteome of human fibroblast (WI38. Cytosolic and nuclear fractions of WI38 cells, empty vector transfected WI38 (WI38-HPV and hTERT WI38 cells were submitted to a 2D-DIGE (Two-Dimensional Differential In-Gel Electrophoresis analysis. Only spots that had a similar abundance in WI38 and WI38-HPV, but were differentially expressed in WI38 hTERT were selected for MS identification. This method directly points to the proteins linked with the hTERT expression. Number of false positive differentially expressed proteins has been excluded by using control WI38-HPV cells. The proteome alteration induced by hTERT WI38 transfection should be taken into account in subsequent use of the cell line for anti-telomerase drugs evaluation. Results 2D-DIGE experiment shows that 57 spots out of 2246 are significantly differentially expressed in the cytosolic fraction due to hTERT transfection, and 38 were confidently identified. In the nuclear fraction, 44 spots out of 2172 were selected in the differential proteome analysis, and 14 were identified. The results show that, in addition to elongating telomeres, hTERT gene transfection has other physiological roles, among which an enhanced ER capacity and a potent cell protection against apoptosis. Conclusion We show that the methodology reduces the complexity of the proteome analysis and highlights proteins implicated in other processes than telomere elongation. hTERT induced proteome changes suggest

  9. Optimizing conditions for calcium phosphate mediated transient transfection

    Directory of Open Access Journals (Sweden)

    Ling Guo

    2017-03-01

    Conclusions: Calcium phosphate mediated transfection is the most low-cost approach to introduce recombinant DNA into culture cells. However, the utility of this procedure is limited in highly-differentiated cells. Here we describe the specific HBS-buffered saline, PH, glycerol shock, vortex strength, transfection medium, and particle concentrations conditions necessary to optimize this transfection method in highly differentiated cells.

  10. Transfection efficiency of chitosan and thiolated chitosan in retinal pigment epithelium cells: A comparative study

    Directory of Open Access Journals (Sweden)

    Ana V Oliveira

    2013-01-01

    Full Text Available Objective: Gene therapy relies on efficient vector for a therapeutic effect. Efficient non-viral vectors are sought as an alternative to viral vectors. Chitosan, a cationic polymer, has been studied for its gene delivery potential. In this work, disulfide bond containing groups were covalently added to chitosan to improve the transfection efficiency. These bonds can be cleaved by cytoplasmic glutathione, thus, releasing the DNA load more efficiently. Materials and Methods: Chitosan and thiolated chitosan nanoparticles (NPs were prepared in order to obtain a NH3 + :PO4− ratio of 5:1 and characterized for plasmid DNA complexation and release efficiency. Cytotoxicity and gene delivery studies were carried out on retinal pigment epithelial cells. Results: In this work, we show that chitosan was effectively modified to incorporate a disulfide bond. The transfection efficiency of chitosan and thiolated chitosan varied according to the cell line used, however, thiolation did not seem to significantly improve transfection efficiency. Conclusion: The apparent lack of improvement in transfection efficiency of the thiolated chitosan NPs is most likely due to its size increase and charge inversion relatively to chitosan. Therefore, for retinal cells, thiolated chitosan does not seem to constitute an efficient strategy for gene delivery.

  11. Nonbilayer phase of lipoplex-membrane mixture determines endosomal escape of genetic cargo and transfection efficiency

    NARCIS (Netherlands)

    Zuhorn, IS; Bakowsky, U; Polushkin, E; Visser, WH; Stuart, MCA; Engberts, JBFN; Hoekstra, D; Visser, Willy H.

    Cationic lipids are widely used for gene delivery, and inclusion of dioleoylphosphatidylethanolamine (DOPE) as a helper lipid in cationic lipid-DNA formulations often promotes transfection efficacy. To investigate the significance of DOPE's preference to adopt a hexagonal phase in the mechanism of

  12. Gene Electrotransfer to Skin; Review of Existing Literature and Clinical Perspectives

    DEFF Research Database (Denmark)

    Gothelf, A.; Gehl, Julie

    2010-01-01

    Gene electrotransfer, which designates the combination of gene transfer and electroporation, is a non-viral means for transfecting genes into cells and tissues. It is a safe and efficient method and reports regarding the use of this technique in a variety of animal models and organs have been...... to now more than 40 papers have been published in which gene electrotransfer was the technique used for gene transfection to skin in vivo. The aim of this review is to summarize which plasmids were injected and the electrical parameters applied. Furthermore an overview of the clinical perspectives...

  13. Differentiation of Odontoblast-Like Cells From Mouse Induced Pluripotent Stem Cells by Pax9 and Bmp4 Transfection.

    Science.gov (United States)

    Seki, Daisuke; Takeshita, Nobuo; Oyanagi, Toshihito; Sasaki, Shutaro; Takano, Ikuko; Hasegawa, Masakazu; Takano-Yamamoto, Teruko

    2015-09-01

    The field of tooth regeneration has progressed in recent years, and human tooth regeneration could become viable in the future. Because induced pluripotent stem (iPS) cells can differentiate into odontogenic cells given appropriate conditions, iPS cells are a potential cell source for tooth regeneration. However, a definitive method to induce iPS cell-derived odontogenic cells has not been established. We describe a novel method of odontoblast differentiation from iPS cells using gene transfection. We generated mouse iPS cell-derived neural crest-like cells (iNCLCs), which exhibited neural crest markers. Next, we differentiated iNCLCs into odontoblast-like cells by transfection of Pax9 and Bmp4 expression plasmids. Exogenous Pax9 upregulated expression of Msx1 and dentin matrix protein 1 (Dmp1) in iNCLCs but not bone morphogenetic protein 4 (Bmp4) or dentin sialophosphoprotein (Dspp). Exogenous Bmp4 upregulated expression of Msx1, Dmp1, and Dspp in iNCLCs, but not Pax9. Moreover, cotransfection of Pax9 and Bmp4 plasmids in iNCLCs revealed a higher expression of Pax9 than when Pax9 plasmid was used alone. In contrast, exogenous Pax9 downregulated Bmp4 overexpression. Cotransfection of Pax9 and Bmp4 synergistically upregulated Dmp1 expression; however, Pax9 overexpression downregulated exogenous Bmp4-induced Dspp expression. Together, these findings suggest that an interaction between exogenous Pax9- and Bmp4-induced signaling modulated Dmp1 and Dspp expression. In conclusion, transfection of Pax9 and Bmp4 expression plasmids in iNCLCs induced gene expression associated with odontoblast differentiation, suggesting that iNCLCs differentiated into odontoblast-like cells. The iPS cell-derived odontoblast-like cells could be a useful cell source for tooth regeneration. It has been reported that induced pluripotent stem (iPS) cells differentiate into odontogenic cells by administration of recombinant growth factors and coculture with odontogenic cells. Therefore, they can

  14. siRNA transfection in larvae of the barnacle Amphibalanus amphitrite

    KAUST Repository

    Zhang, G.

    2015-06-25

    RNA interference (RNAi) provides an efficient and specific technique for functional genomic studies. Yet, no successful application of RNAi has been reported in barnacles. In this study, siRNA against p38 MAPK was synthesized and then transfected into A. amphitrite larvae at either the nauplius or cyprid stage, or at both stages. Effects of siRNA transfection on the p38 MAPK level were hardly detectable in the cyprids when they were transfected at the nauplius stage. In contrast, larvae that were transfected at the cyprid stage showed lower levels of p38 MAPK than the blank and reagent controls. However, significantly decreased levels of phosphorylated p38 MAPK (pp38 MAPK) and reduced settlement rates were observed only in ‘double transfections’, in which larvae were exposed to siRNA solution at both the nauplius and cyprid stages. A relatively longer transfection time and more larval cells directly exposed to siRNA might explain the higher efficiency of double transfection experiments.

  15. siRNA transfection in larvae of the barnacle Amphibalanus amphitrite

    KAUST Repository

    Zhang, G.; He, L.-S.; Wong, Y. H.; Yu, L.; Qian, P.-Y.

    2015-01-01

    RNA interference (RNAi) provides an efficient and specific technique for functional genomic studies. Yet, no successful application of RNAi has been reported in barnacles. In this study, siRNA against p38 MAPK was synthesized and then transfected into A. amphitrite larvae at either the nauplius or cyprid stage, or at both stages. Effects of siRNA transfection on the p38 MAPK level were hardly detectable in the cyprids when they were transfected at the nauplius stage. In contrast, larvae that were transfected at the cyprid stage showed lower levels of p38 MAPK than the blank and reagent controls. However, significantly decreased levels of phosphorylated p38 MAPK (pp38 MAPK) and reduced settlement rates were observed only in ‘double transfections’, in which larvae were exposed to siRNA solution at both the nauplius and cyprid stages. A relatively longer transfection time and more larval cells directly exposed to siRNA might explain the higher efficiency of double transfection experiments.

  16. Cloning-free regulated monitoring of reporter and gene expression

    Directory of Open Access Journals (Sweden)

    Demirkaya Omer

    2009-03-01

    Full Text Available Abstract Background The majority of the promoters, their regulatory elements, and their variations in the human genome remain unknown. Reporter gene technology for transcriptional activity is a widely used tool for the study of promoter structure, gene regulation, and signaling pathways. Construction of transcriptional reporter vectors, including use of cis-acting sequences, requires cloning and time-demanding manipulations, particularly with introduced mutations. Results In this report, we describe a cloning-free strategy to generate transcriptionally-controllable linear reporter constructs. This approach was applied in common transcriptional models of inflammatory response and the interferon system. In addition, it was used to delineate minimal transcriptional activity of selected ribosomal protein promoters. The approach was tested for conversion of genes into TetO-inducible/repressible expression cassettes. Conclusion The simple introduction and tuning of any transcriptional control in the linear DNA product renders promoter activation and regulated gene studies simple and versatile.

  17. GAL4 enhancer trap strains with reporter gene expression during ...

    Indian Academy of Sciences (India)

    the development of adult brain in Drosophila melanogaster. C. R. VENKATESH ... vous system (CNS), at different time points during the pupal stage—a critical .... in frontal view, with further reduced reporter gene expression. Orthodenticle and ...

  18. New Transfection Agents Based on Liposomes Containing Biosurfactant MEL-A.

    Science.gov (United States)

    Nakanishi, Mamoru; Inoh, Yoshikazu; Furuno, Tadahide

    2013-08-16

    Nano vectors are useful tools to deliver foreign DNAs, oligonucleotides, and small interfering double-stranded RNAs (siRNAs) into mammalian cells with gene transfection and gene regulation. In such experiments we have found the liposomes with a biosurfacant mannosylerythriol lipid (MEL-A) are useful because of their high transfer efficiency, and their unique mechanism to transfer genes to target cells with the lowest toxicity. In the present review we will describe our current work, which may contribute to the great advance of gene transfer to target cells and gene regulations. For more than two decades, the liposome technologies have changed dramatically and various methods have been proposed in the fields of biochemistry, cell biology, biotechnology, and so on. In addition, they were towards to pharmaceutics and clinical applications. The liposome technologies were expected to use gene therapy, however, they have not reached a requested goal as of yet. In the present paper we would like to present an approach using a biosurfactant, MEL-A, which is a surface-active compound produced by microorganisms growing on water-insoluble substrates and increases efficiency in gene transfection. The present work shows new transfection agents based on liposomes containing biosurfactant MEL-A.

  19. New Transfection Agents Based on Liposomes Containing Biosurfactant MEL-A

    Directory of Open Access Journals (Sweden)

    Tadahide Furuno

    2013-08-01

    Full Text Available Nano vectors are useful tools to deliver foreign DNAs, oligonucleotides, and small interfering double-stranded RNAs (siRNAs into mammalian cells with gene transfection and gene regulation. In such experiments we have found the liposomes with a biosurfacant mannosylerythriol lipid (MEL-A are useful because of their high transfer efficiency, and their unique mechanism to transfer genes to target cells with the lowest toxicity. In the present review we will describe our current work, which may contribute to the great advance of gene transfer to target cells and gene regulations. For more than two decades, the liposome technologies have changed dramatically and various methods have been proposed in the fields of biochemistry, cell biology, biotechnology, and so on. In addition, they were towards to pharmaceutics and clinical applications. The liposome technologies were expected to use gene therapy, however, they have not reached a requested goal as of yet. In the present paper we would like to present an approach using a biosurfactant, MEL-A, which is a surface-active compound produced by microorganisms growing on water-insoluble substrates and increases efficiency in gene transfection. The present work shows new transfection agents based on liposomes containing biosurfactant MEL-A.

  20. Development of a New Reporter Gene System-dsRed/Xanthine Phosphoribosyltransferase-Xanthine for Molecular Imaging of Processes Behind the Intact Blood-Brain Barrier

    Directory of Open Access Journals (Sweden)

    Mikhail Doubrovin

    2003-04-01

    Full Text Available We report the development of a novel dual-modality fusion reporter gene system consisting of Escherichia coli xanthine phosphoribosyltransferase (XPRT for nuclear imaging with radiolabeled xanthine and Discosoma red fluorescent protein for optical fluorescent imaging applications. The dsRed/XPRT fusion gene was successfully created and stably transduced into RG2 glioma cells, and both reporters were shown to be functional. The level of dsRed fluorescence directly correlated with XPRT enzymatic activity as measured by ribophosphorylation of [14C]-xanthine was in vitro (Ki = 0.124 ± 0.008 vs. 0.00031 ± 0.00005 mL/min/g in parental cell line, and [*]-xanthine octanol/water partition coefficient was 0.20 at pH = 7.4 (logP = 0.69, meeting requirements for the blood-brain barrier (BBB penetrating tracer. In the in vivo experiment, the concentration of [* C]-xanthine in the normal brain varied from 0.20 to 0.16 + 0.05% dose/g under 0.87 + 0.24% dose/g plasma radiotracer concentration. The accumulation in vivo in the transfected flank tumor was to 2.4 ± 0.3% dose/g, compared to 0.78 ± 0.02% dose/g and 0.64 ± 0.05% dose/g in the control flank tumors and intact muscle, respectively. [14C]-Xanthine appeared to be capable of specific accumulation in the transfected infiltrative brain tumor (RG2-dsRed/XPRT, which corresponded to the 585 nm fluorescent signal obtained from the adjacent cryosections. The images of endogenous gene expression with the “sensory system” have to be normalized for the transfection efficiency based on the “beacon system” image data. Such an approach requires two different “reporter genes” and two different “reporter substrates.” Therefore, the novel dsRed/XPRT fusion gene can be used as a multimodality reporter system in the biological applications requiring two independent reporter genes, including the cells located behind the BBB.

  1. Transfection of brain capillary endothelial cells in primary culture with defined blood-brain barrier properties.

    Science.gov (United States)

    Burkhart, Annette; Thomsen, Louiza Bohn; Thomsen, Maj Schneider; Lichota, Jacek; Fazakas, Csilla; Krizbai, István; Moos, Torben

    2015-08-07

    Primary brain capillary endothelial cells (BCECs) are a promising tool to study the blood-brain barrier (BBB) in vitro, as they maintain many important characteristics of the BBB in vivo, especially when co-cultured with pericytes and/or astrocytes. A novel strategy for drug delivery to the brain is to transform BCECs into protein factories by genetic modifications leading to secretion of otherwise BBB impermeable proteins into the central nervous system. However, a huge challenge underlying this strategy is to enable transfection of non-mitotic BCECs, taking a non-viral approach. We therefore aimed to study transfection in primary, non-mitotic BCECs cultured with defined BBB properties without disrupting the cells' integrity. Primary cultures of BCECs, pericytes and astrocytes were generated from rat brains and used in three different in vitro BBB experimental arrangements, which were characterised based on a their expression of tight junction proteins and other BBB specific proteins, high trans-endothelial electrical resistance (TEER), and low passive permeability to radiolabeled mannitol. Recombinant gene expression and protein synthesis were examined in primary BCECs. The BCECs were transfected using a commercially available transfection agent Turbofect™ to express the red fluorescent protein HcRed1-C1. The BCECs were transfected at different time points to monitor transfection in relation to mitotic or non-mitotic cells, as indicated by fluorescence-activated cell sorting analysis after 5-and 6-carboxylfluorescein diacetate succinidyl ester incorporation. The cell cultures exhibited important BBB characteristics judged from their expression of BBB specific proteins, high TEER values, and low passive permeability. Among the three in vitro BBB models, co-culturing with BCECs and astrocytes was well suited for the transfection studies. Transfection was independent of cell division and with equal efficacy between the mitotic and non-mitotic BCECs. Importantly

  2. A two-cassette reporter system for assessing target gene translation and target gene product inclusion body formation

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a dual cassette reporter system capable of assessing target gene translation and target gene product folding. The present invention further relates to vectors and host cells comprising the dual cassette reporter system. In addition the invention relates to the use...... of the dual cassette reporter system for assessing target gene translation and target gene product folding....

  3. Transfection Agent Induced Nanoparticle Cell Loading

    Directory of Open Access Journals (Sweden)

    Karin Montet-Abou

    2005-07-01

    Full Text Available Loading cells with magnetic nanoparticles, and tracking their fate in vivo by high resolution MRI, is an attractive approach for enhancing the efficacy of cell-based therapies including those utilizing hematopoietic stem cells, neuroprogenitor cells, and T cells. The transfection agent (internalization agent assisted loading with the Feridex IV® nanoparticle is an attractive method of loading because of the low cost of materials, and possible low regulatory barriers for eventual clinical use. We therefore explored the interaction between Feridex IV® and three internalization agents protamine (PRO, polylysine (PLL, and lipofectamine (LFA. Feridex reacted with internalization agents to form aggregates, except when either the internalization agent or Feridex was present in large excess. When Jurkat T cells were incubated with Feridex/LFA or Feridex/PRO mixtures, and washed by centrifugation, nanoparticle aggregates co-purified with cells. With C17.2 cells large iron oxide particles adhered to the cell surface. At 30 μg/mL Feridex and 3 μg/mL LFA, internalization was largely mediated by LFA and was largely cytoplasmic. However, we found that the conditions used to label cells with Feridex and transfection agents need to be carefully selected to avoid the problems of surface adsorption and nanoparticle precipitation.

  4. Establishing malaria parasite transfection technology in South Africa.

    CSIR Research Space (South Africa)

    Van Brummelen, AC

    2010-01-01

    Full Text Available reported to have bidirectional promoter activity, was utilized to drive expression through two genes (i.e. the antibiotic-resistance gene, human dhfr and the reporter gene) in a head-to-head orientation. In addition, protocols were adjusted by including DNA...

  5. Transplantation of neurotrophin-3-transfected bone marrow mesenchymal stem cells for the repair of spinal cord injury

    OpenAIRE

    Dong, Yuzhen; Yang, Libin; Yang, Lin; Zhao, Hongxing; Zhang, Chao; Wu, Dapeng

    2014-01-01

    Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesenchymal stem cells in vivo remains a problem. Neurotrophin-3 promotes motor neuron survival and it is hypothesized that its transfection can enhance the therapeutic effect. We show that in vitro transfection of neurotrophin-3 gene increases the number of bone marrow mesenchymal stem cells in the region of spinal ...

  6. Development of the 5-HT2CR-Tango System Combined with an EGFP Reporter Gene.

    Science.gov (United States)

    Watanabe, Yoshihisa; Tsujimura, Atsushi; Aoki, Miku; Taguchi, Katsutoshi; Tanaka, Masaki

    2016-02-01

    The serotonin 2C receptor (5-HT2CR) is a G-protein-coupled receptor implicated in emotion, feeding, reward, and cognition. 5-HT2CRs are pharmacological targets for mental disorders and metabolic and reward system abnormalities, as alterations in 5-HT2CR expression, RNA editing, and SNPs are involved in these disturbances. To date, 5-HT2CR activity has mainly been measured by quantifying inositol phosphate production and intracellular Ca(2+) release, but these assays are not suitable for in vivo analysis. Here, we developed a 5-HT2CR-Tango assay system, a novel analysis tool of 5-HT2CR activity based on the G-protein-coupled receptor (GPCR)-arrestin interaction. With desensitization of activated 5-HT2CR by arrestin, this system converts the 5-HT2CR-arrestin interaction into EGFP reporter gene signal via the LexA transcriptional activation system. For validation of our system, we measured activity of two 5-HT2CR RNA-editing isoforms (INI and VGV) in HEK293 cells transfected with EGFP reporter gene. The INI isoform displayed both higher basal- and 5-HT-stimulated activities than the VGV isoform. Moreover, an inhibitory effect of 5-HT2CR antagonist SB242084 was also detected by 5-HT2CR-Tango system. This novel tool is useful for in vitro high-throughput targeted 5-HT2CR drug screening and can be applied to future in vivo brain function studies associated with 5-HT2CRs in transgenic animal models.

  7. Establishment of a hepatocellular carcinoma cell line expressing dual reporter genes: sodium iodide symporter (NIS) and enhanced green fluorescence protein (EGFP)

    International Nuclear Information System (INIS)

    Kwak, Won Jung; Koo, Bon Chul; Kwon, Mo Sun

    2007-01-01

    Dual reporter gene imaging has several advantages for more sophisticated molecular imaging studies such as gene therapy monitoring. Herein, we have constructed hepatoma cell line expressing dual reporter genes of sodium iodide symporter (NIS) and enhanced green fluorescence protein (EGFP), and the functionalities of the genes were evaluated in vivo by nuclear and optical imaging. A pRetro-PN vector was constructed after separating NIS gene from pcDNA-NIS. RSV-EGFP-WPRE fragment separated from pLNRGW was cloned into pRetro-PN vector. The final vector expressing dual reporter genes was named pRetro-PNRGW. A human hepatoma (HepG2) cells were transfected by the retrovirus containing NIS and EGFP gene (HepG2-NE). Expression of NIS gene was confirmed by RT-PCR, radioiodine uptake and efflux studies. Expression of EGFP was confirmed by RT-PCR and fluorescence microscope. The HepG2 and HepG2-NE cells were implanted in shoulder and hindlimb of nude mice, then fluorescence image, gamma camera image and I-124 microPET image were undertaken. The HepG2-NE cell was successfully constructed. RT-PCR showed NIS and EGFP mRNA expression. About 50% of cells showed fluorescence. The iodine uptake of NIS-expressed cells was about 9 times higher than control. In efflux study, T 1/2 of HepG2-NE cells was 9 min. HepG2-NE xenograft showed high signal-to-background fluorescent spots and higher iodine-uptake compared to those of HepG2 xenograft. A hepatoma cell line expressing NIS and EGFP dual reporter genes was successfully constructed and could be used as a potential either by therapeutic gene or imaging reporter gene

  8. mRNA transfection of mouse and human neural stem cell cultures

    OpenAIRE

    McLenachan, Samuel; Zhang, D.; Palomo, A.B.; Edel, Michael John; Chen, F.K.

    2013-01-01

    The use of synthetic mRNA as an alternative gene delivery vector to traditional DNA-based constructs provides an effective method for inducing transient gene expression in cell cultures without genetic modification. Delivery of mRNA has been proposed as a safer alternative to viral vectors in the induction of pluripotent cells for regenerative therapies. Although mRNA transfection of fibroblasts, dendritic and embryonic stem cells has been described, mRNA delivery to neurosphere cultures has ...

  9. Development of a universal RNA beacon for exogenous gene detection.

    Science.gov (United States)

    Guo, Yuanjian; Lu, Zhongju; Cohen, Ira Stephen; Scarlata, Suzanne

    2015-05-01

    Stem cell therapy requires a nontoxic and high-throughput method to achieve a pure cell population to prevent teratomas that can occur if even one cell in the implant has not been transformed. A promising method to detect and separate cells expressing a particular gene is RNA beacon technology. However, developing a successful, specific beacon to a particular transfected gene can take months to develop and in some cases is impossible. Here, we report on an off-the-shelf universal beacon that decreases the time and cost of applying beacon technology to select any living cell population transfected with an exogenous gene. ©AlphaMed Press.

  10. Rat embryo cells immortalized with transfected oncogenes are transformed by gamma irradiation.

    Science.gov (United States)

    Endlich, B; Salavati, R; Sullivan, T; Ling, C C

    1992-12-01

    Cesium-137 gamma rays were used to transform rat embryo cells (REC) which were first transfected with activated c-myc or c-Ha-ras oncogenes to produce immortal cell lines (REC:myc and REC:ras). When exposed to 6 Gy of 137Cs gamma rays, some cells became morphologically transformed with focus formation frequencies of approximately 3 x 10(-4) for REC:myc and approximately 1 x 10(-4) for REC:ras, respectively. Cells isolated from foci of gamma-ray-transformed REC:myc (REC:myc:gamma) formed anchorage-independent colonies and were tumorigenic in nude mice, but foci from gamma-ray-transformed REC:ras (REC:ras:gamma) did not exhibit either of these criteria of transformation. Similar to the results with gamma irradiation, we observed a sequence-dependent phenomenon when myc and ras were transfected into REC, one at a time. REC immortalized by ras transfection were not converted to a tumorigenic phenotype by secondary transfection with myc, but REC transfected with myc were very susceptible to transformation by subsequent ras transfection. This suggests that myc-immortalized cells are more permissive to transformation via secondary treatments. In sequentially transfected REC, myc expression was high whether it was transfected first or second, whereas ras expression was highest when the ras gene was transfected secondarily into myc-containing REC. Molecular analysis of REC:ras:gamma transformants showed no alterations in structure of the transfected ras or of the endogenous ras, myc, p53, or fos genes. The expression of ras and p53 was increased in some isolates of REC:ras:gamma, but myc and fos expression were not affected. Similarly, REC:myc:gamma transformants did not demonstrate rearrangement or amplification of the transfected or the endogenous myc genes, or of the potentially cooperating Ha-, Ki-, or N-ras genes. Northern hybridization analysis revealed increased expression of N-ras in two isolates, REC:myc:gamma 33 and gamma 41, but no alterations in the expression

  11. Tumor transfection after systemic injection of DNA lipid nanocapsules.

    Science.gov (United States)

    Morille, Marie; Passirani, Catherine; Dufort, Sandrine; Bastiat, Guillaume; Pitard, Bruno; Coll, Jean-Luc; Benoit, Jean-Pierre

    2011-03-01

    With the goal of generating an efficient vector for systemic gene delivery, a new kind of nanocarrier consisting of lipid nanocapsules encapsulating DOTAP/DOPE lipoplexes (DNA LNCs) was pegylated by the post-insertion of amphiphilic and flexible polymers. The aim of this surface modification was to create a long-circulating vector, able to circulate in the blood stream and efficient in transfecting tumoral cells after passive targeting by enhanced permeability and retention effect (EPR effect). PEG conformation, electrostatic features, and hydrophylicity are known to be important factors able to influence the pharmacokinetic behaviour of vectors. In this context, the surface structure characteristics of the newly pegylated DNA LNCs were studied by measuring electrophoretic mobility as a function of ionic strength in order to establish a correlation between surface properties and in vivo performance of the vector. Finally, thanks to this PEGylation, gene expression was measured up to 84-fold higher in tumor compared to other tested organs after intravenous injection. The present results indicate that PEGylated DNA LNCs are promising carriers for an efficient cancer gene therapy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. The progress of PET based reporter gene imaging

    International Nuclear Information System (INIS)

    Zhao Wei; Zhang Xiuli

    2005-01-01

    More than two decades of intense research have allowed gene therapy to move from the laboratory to the clinical setting, where its use for the treatment of human pathologies has been considerably increased in the last years. However, many crucial questions remain to be solved in this challenging field. In vivo imaging with positron emission tomography (PET) by combination of the appropriate PET reporter gene and PET reporter probe could provide invaluable qualitative and quantitative information to answer multiple unsolved questions about gene therapy. PET imaging could be used to define parameters not available by other techniques that are of substantial interest not only for the proper understanding of the gene therapy process, but also for its future development and clinical application in humans. (authors)

  13. Effects of Circular DNA Length on Transfection Efficiency by Electroporation into HeLa Cells.

    Science.gov (United States)

    Hornstein, Benjamin D; Roman, Dany; Arévalo-Soliz, Lirio M; Engevik, Melinda A; Zechiedrich, Lynn

    2016-01-01

    The ability to produce extremely small and circular supercoiled vectors has opened new territory for improving non-viral gene therapy vectors. In this work, we compared transfection of supercoiled DNA vectors ranging from 383 to 4,548 bp, each encoding shRNA against GFP under control of the H1 promoter. We assessed knockdown of GFP by electroporation into HeLa cells. All of our vectors entered cells in comparable numbers when electroporated with equal moles of DNA. Despite similar cell entry, we found length-dependent differences in how efficiently the vectors knocked down GFP. As vector length increased up to 1,869 bp, GFP knockdown efficiency per mole of transfected DNA increased. From 1,869 to 4,257 bp, GFP knockdown efficiency per mole was steady, then decreased with increasing vector length. In comparing GFP knockdown with equal masses of vectors, we found that the shorter vectors transfect more efficiently per nanogram of DNA transfected. Our results rule out cell entry and DNA mass as determining factors for gene knockdown efficiency via electroporation. The length-dependent effects we have uncovered are likely explained by differences in nuclear translocation or transcription. These data add an important step towards clinical applications of non-viral vector delivery.

  14. Non-viral bone morphogenetic protein 2 transfection of rat dental pulp stem cells using calcium phosphate nanoparticles as carriers.

    NARCIS (Netherlands)

    Yang, X.; Walboomers, X.F.; Dolder, J. van den; Yang, F.; Bian, Z.; Fan, M.; Jansen, J.A.

    2008-01-01

    Calcium phosphate nanoparticles have shown potential as non-viral vectors for gene delivery. The aim of this study was to induce bone morphogenetic protein (Bmp)2 transfection in rat dental pulp stem cells using calcium phosphate nanoparticles as a gene vector and then to evaluate the efficiency and

  15. Evaluation of transcriptional activity of the oestrogen receptor with sodium iodide symporter as an imaging reporter gene.

    Science.gov (United States)

    Kang, Joo Hyun; Chung, June-Key; Lee, Yong Jin; Kim, Kwang Il; Jeong, Jae Min; Lee, Dong Soo; Lee, Myung Chul

    2006-10-01

    Oestrogen receptors are ligand-dependent transcription factors whose activity is modulated either by oestrogens or by an alternative signalling pathway. Oestrogen receptors interact via a specific DNA-binding domain, the oestrogen responsive element (ERE), in the promoter region of sensitive genes. This binding leads to an initiation of gene expression and hormonal effects. To determine the transcriptional activity of the oestrogen receptor, we developed a molecular imaging system using sodium iodide symporter (NIS) as a reporter gene. The NIS reporter gene was placed under the control of an artificial ERE derived from pERE-TA-SEAP and named as pERE-NIS. pERE-NIS was transferred to MCF-7, human breast cancer cells, which highly expressed oestrogen receptor-alpha with lipofectamine. Stably expressing cells were generated by selection with G418 for 14 days. After treatment of 17beta-oestradiol and tamoxifen with serial doses, the (125)I uptake was measured for the determination of NIS expression. The inhibition of NIS activity was performed with 50 micromol x l(-1) potassium perchlorate. The MCF7/pERE-NIS treated with 17beta-oestradiol accumulated (125)I up to 70-80% higher than did non-treated cells. NIS expression was increased according to increasing doses of 17beta-oestradiol. MCF7/pERE-NIS treated with tamoxifen also accumulated (125)I up to 50% higher than did non-treated cells. Potassium perchlorate completely inhibited (125)I uptake. When MDA-MB231 cells, the oestrogen receptor-negative breast cancer cells, were transfected with pERE-NIS, (125)I uptake of MDA-MB-231/pERE-NIS did not increase. This pERE-NIS reporter system is sufficiently sensitive for monitoring transcriptional activity of the oestrogen receptor. Therefore, cis-enhancer reporter systems with ERE will be applicable to the development of a novel selective oestrogen receptor modulator with low toxicity and high efficacy.

  16. Covalently bound DNA on naked iron oxide nanoparticles: Intelligent colloidal nano-vector for cell transfection.

    Science.gov (United States)

    Magro, Massimiliano; Martinello, Tiziana; Bonaiuto, Emanuela; Gomiero, Chiara; Baratella, Davide; Zoppellaro, Giorgio; Cozza, Giorgio; Patruno, Marco; Zboril, Radek; Vianello, Fabio

    2017-11-01

    Conversely to common coated iron oxide nanoparticles, novel naked surface active maghemite nanoparticles (SAMNs) can covalently bind DNA. Plasmid (pDNA) harboring the coding gene for GFP was directly chemisorbed onto SAMNs, leading to a novel DNA nanovector (SAMN@pDNA). The spontaneous internalization of SAMN@pDNA into cells was compared with an extensively studied fluorescent SAMN derivative (SAMN@RITC). Moreover, the transfection efficiency of SAMN@pDNA was evaluated and explained by computational model. SAMN@pDNA was prepared and characterized by spectroscopic and computational methods, and molecular dynamic simulation. The size and hydrodynamic properties of SAMN@pDNA and SAMN@RITC were studied by electron transmission microscopy, light scattering and zeta-potential. The two nanomaterials were tested by confocal scanning microscopy on equine peripheral blood-derived mesenchymal stem cells (ePB-MSCs) and GFP expression by SAMN@pDNA was determined. Nanomaterials characterized by similar hydrodynamic properties were successfully internalized and stored into mesenchymal stem cells. Transfection by SAMN@pDNA occurred and GFP expression was higher than lipofectamine procedure, even in the absence of an external magnetic field. A computational model clarified that transfection efficiency can be ascribed to DNA availability inside cells. Direct covalent binding of DNA on naked magnetic nanoparticles led to an extremely robust gene delivery tool. Hydrodynamic and chemical-physical properties of SAMN@pDNA were responsible of the successful uptake by cells and of the efficiency of GFP gene transfection. SAMNs are characterized by colloidal stability, excellent cell uptake, persistence in the host cells, low toxicity and are proposed as novel intelligent DNA nanovectors for efficient cell transfection. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. BMP7 transfection induces in-vitro osteogenic differentiation of dental pulp mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Ka Po John Yau

    2013-01-01

    Full Text Available Objective: To assess whether in-vitro osteogenic differentiation of human dental pulp mesenchymal stem cells can be induced by transient transfection with the gene encoding human bone morphogenic protein 7 (BMP7. Materials and Methods: A mesenchymal stem cell population was isolated from the dental pulp of two extracted permanent premolars, expanded and characterized. The human BMP7 gene, as a recombinant pcDNA3.1/V5-His-TOPO-BMP7 plasmid, was transfected into the cells. Three negative controls were used: No plasmid, empty vector, and an unrelated vector encoding green fluorescent protein. After the interval of 24 and 48 h, mRNA levels of alkaline phosphatase and osteocalcin as markers of in-vitro osteogenic differentiation were measured by real-time polymerase chain reaction and standardized against β-actin mRNA levels. Results: The level of alkaline phosphatase mRNA was significantly higher for the BMP7 group than for all three negative controls 48 h after transfection (706.9 vs. 11.24 for untransfected cells, 78.05 for empty vector, and 73.10 for green fluorescent protein vector. The level of osteocalcin mRNA was significantly higher for the BMP7 group than for all three negative controls 24 h after transfection (1.0, however, decreased after another 24 h. Conclusions: In-vitro osteoblastic differentiation of human dental pulp mesenchymal stem cells, as indicated by expression of alkaline phosphatase and osteocalcin, can be induced by transient transfection with the BMP7 gene.

  18. Liposome-based vascular endothelial growth factor-165 transfection with skeletal myoblast for treatment of ischaemic limb disease.

    Science.gov (United States)

    Ye, Lei; Haider, Husnain Kh; Esa, Wahidah Bte; Su, Liping; Law, Peter K; Zhang, Wei; Lim, Yeanteng; Poh, Kian Keong; Sim, Eugene K W

    2010-01-01

    The study aims to use cholesterol (Chol) + DOTAP liposome (CD liposome) based human vascular endothelial growth factor-165 (VEGF(165)) gene transfer into skeletal myoblasts (SkMs) for treatment of acute hind limb ischaemia in a rabbit model. The feasibility and efficacy of CD liposome mediated gene transfer with rabbit SkMs were characterized using plasmid carrying enhanced green fluorescent protein (pEGFP) and assessed by flow cytometry. After optimization, SkMs were transfected with CD lipoplexes carrying plasmid-VEGF(165) (CD-pVEGF(165)) and transplanted into rabbit ischaemic limb. Animals were randomized to receive intramuscular injection of Medium199 (M199; group 1), non-transfected SkM (group 2) or CD-pVEGF(165) transfected SkM (group 3). Flow cytometry revealed that up to 16% rabbit SkMs were successfully transfected with pEGFP. Based on the optimized transfection condition, transfected rabbit SkM expressed VEGF(165) up to day 18 with peak at day 2. SkMs were observed in all cell-transplanted groups, as visualized with 6-diamidino-2-phenylindole and bromodeoxyuridine. Angiographic blood vessel score revealed increased collateral vessel development in group 3 (39.7 +/- 2.0) compared with group 2 (21.6 +/- 1.1%, P limb and may serve as a safe and new therapeutic modality for the repair of acute ischaemic limb disease.

  19. Advances of reporter gene monitoring stem cell therapy

    International Nuclear Information System (INIS)

    Zhou Xiang; Yin Hongyan; Zhang Yifan

    2010-01-01

    Stem cell therapy research has made great progress, demonstrating a broad application prospects. However, stem cell therapy as a new disease treatment, there are still many problems to be solved. Reporter gene imaging is a rapid development in recent years, a non-invasive, sensitive method of monitoring of stem cells, in particular radionuclide reporter gene imaging has high sensitivity and specificity of the advantages of strong and can carry out imaging of deep tissue and repeat imaging, is a tracer in vivo conditions, the most promising stem cell transplantation technique, showing good prospects for development. (authors)

  20. Repetitive Imaging of Reporter Gene Expression in the Lung

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Richard

    2003-10-01

    Full Text Available Positron emission tomographic imaging is emerging as a powerful technology to monitor reporter transgene expression in the lungs and other organs. However, little information is available about its usefulness for studying gene expression over time. Therefore, we infected 20 rats with a replication-deficient adenovirus containing a fusion gene encoding for a mutant Herpes simplex virus type-1 thymidine kinase and an enhanced green fluorescent protein. Five additional rats were infected with a control virus. Pulmonary gene transfer was performed via intratracheal administration of vector using a surfactant-based method. Imaging was performed 4–6 hr, and 4, 7, and 10 days after gene transfer, using 9-(4-[18F]-fluoro-3-hydroxymethylbutylguanine, an imaging substrate for the mutant kinase. Lung tracer uptake assessed with imaging was moderately but significantly increased 4–6 hr after gene transfer, was maximal after 4 days, and was no longer detectable by 10 days. The temporal pattern of transgene expression measured ex vivo with in vitro assays of thymidine kinase activity and green fluorescent protein was similar to imaging. In conclusion, positron emission tomography is a reliable new tool to evaluate the onset and duration of reporter gene expression noninvasively in the lungs of intact animals.

  1. Reconstructing Dynamic Promoter Activity Profiles from Reporter Gene Data

    DEFF Research Database (Denmark)

    Kannan, Soumya; Sams, Thomas; Maury, Jérôme

    2018-01-01

    activity despite the fact that the observed output may be dynamic and is a number of steps away from the transcription process. In fact, some promoters that are often thought of as constitutive can show changes in activity when growth conditions change. For these reasons, we have developed a system......Accurate characterization of promoter activity is important when designing expression systems for systems biology and metabolic engineering applications. Promoters that respond to changes in the environment enable the dynamic control of gene expression without the necessity of inducer compounds......, for example. However, the dynamic nature of these processes poses challenges for estimating promoter activity. Most experimental approaches utilize reporter gene expression to estimate promoter activity. Typically the reporter gene encodes a fluorescent protein that is used to infer a constant promoter...

  2. Construction of rat beta defensin-2 eukaryotic expression vector and expression in the transfected rat corneal epithelial cell

    Directory of Open Access Journals (Sweden)

    Jing Dan

    2017-03-01

    Full Text Available AIM: To construct a recombinant eukaryotic expression vector of rat beta defensin-2(rBD-2, transfect it into the rat corneal epithelial cells with lipofection, determine the expression of target gene in the transfected cells, and discuss the potentiality of recombinant plasmid expressed in corneal epithelial cells, hoping to provide an experimental foundation for further study on the antimicrobial activity of rBD-2 in vitro and in vivo and to assess the probability of defensins as a new application for infectious corneal diseases in the future. METHODS: The synthetic rBD-2 DNA fragment was inserted between the XhoI and BamHI restriction enzyme cutting sites of eukaryotic expression vector pIRES2-ZsGreen1 to construct the recombinant plasmid pIRES2-ZsGreen1-rBD-2, then transformed it into E.coli DH5α, positive clones were screened by kanamycin and identified with restriction endonucleases and sequencing analysis. Transfection into the rat corneal epithelial cells was performed by lipofection. Then the experiment was divided into three groups: rat corneal epithelial cell was transfected with the recombinant plasmid pIRES2- ZsGreen1-rBD-2, rat corneal epithelial cell was transfected with the empty plasmid pIRES2-ZsGreen1 and the non-transfected group. The inverted fluorescence microscope was used to observe the transfection process. At last, the level of rBD-2 mRNA expressed in the transfected cells and the control groups are compared by the real-time fluoresence relative quantitative PCR. RESULTS: The recombinant eukaryotic expression vector of pIRES2-ZsGreen1-rBD-2 was successfully constructed. The level of rBD-2 mRNA in transfected cells was significantly higher than that in control groups through the real-time fluorescence relative quantitative PCR. CONCLUSION: The recombinant eukaryotic expression vector pIRES2-ZsGreen1-rBD-2 could be transfected into rat corneal epithelial cells, and exogenous rBD-2 gene could be transcripted into mRNA in

  3. Lipofection of rabbit chondrocytes and long lasting expression of a lacZ reporter system in alginate beads.

    Science.gov (United States)

    Stöve, J; Fiedler, J; Huch, K; Günther, K-P; Puhl, W; Brenner, R

    2002-03-01

    Our aim was to investigate the maintenance of the transfection status of non-viral transfected chondrocytes in an alginate culture system. Chondrocytes harvested from rabbit knees were isolated by sequential digestion and cultivated in monolayer culture. At 60-70% cell density, chondrocytes were transfected with different transfection systems (FuGENE6, CaCl2, Lipofectin). A lac Z expression vector (pcDNA 3.1/Myc-His+ lacZ) was used as a reporter system. In order to improve transfection rates, hyaluronidase (4 U/ml) was used prior and during the transfection procedure. Thereafter, transfected cells were either kept in monolayer culture or embedded in alginate beads and kept in culture for up to the next 30 weeks. Transfection efficiency was maximal using FuGENE6TM/DNA at a ratio of 3:2 and hyaluronidase (4 U/ml). Transfection efficiency reached up to 40.8% (+/- 3.2%) after 36 h. In alginate beads lac Z positive cells declined to 8.5% +/- 3.3% after 4 weeks and to 4.6% +/- 3.2% after 12 weeks of culturing. After 30 weeks 3% of chondrocytes still expressed lac Z. In contrast, during culturing in monolayer, no lac Z expression was detectable after 4 weeks. Differentiation status of the chondrocytes was confirmed by histology and immunohistochemistry methods. After successful gene transfer to rabbit chondrocytes the alginate system made it possible to culture lipofected chondrocytes phenotypically stable. Genetically engineered chondrocytes express the lac Z reporter gene over a period of at least 30 weeks. This transfection and culture system provides a promising tool to further investigate the over-expression of growth factors and enzyme inhibitors. Copyright 2002 OsteoArthritis Research Society International.

  4. C-terminal KDEL-modified cystatin C is retained in transfected CHO cells

    DEFF Research Database (Denmark)

    Johansen, Teit Eliot; Vogel, Charlotte Katrine; Schwartz, Thue W.

    1990-01-01

    The significance of a C-terminal tetrapeptide, Lys-Asp-Glu-Leu (KDEL), as a retention signal for the endoplasmatic reticulum was studied using cystatin C, a general thiol protease inhibitor, as the reporter protein. Clones of CHO cells were analyzed after stable transfection with eukaryotic...

  5. Induction of PLSCR1 in a STING/IRF3-dependent manner upon vector transfection in ovarian epithelial cells.

    Directory of Open Access Journals (Sweden)

    Karthik M Kodigepalli

    Full Text Available Toll-like receptors (TLRs are the primary sensors of the innate immune system that recognize pathogenic nucleic acids including double-stranded plasmid DNA (dsDNA. TLR signaling activates multiple pathways including IRF3 which is involved in transcriptional induction of inflammatory cytokines (i.e. interferons (IFNs. Phospholipid scramblase 1, PLSCR1, is a highly inducible IFN-regulated gene mediating anti-viral properties of IFNs. Herein, we report a novel finding that dsDNA transfection in T80 immortalized normal ovarian surface epithelial cell line leads to a marked increase in PLSCR1 mRNA and protein. We also noted a comparable response in primary mammary epithelial cells (HMECs. Similar to IFN-2α treated cells, de novo synthesized PLSCR1 was localized predominantly to the plasma membrane. dsDNA transfection, in T80 and HMEC cells, led to activation of MAPK and IRF3. Although inhibition of MAPK (using U0126 did not modulate PLSCR1 mRNA and protein, IRF3 knockdown (using siRNA significantly ablated the PLSCR1 induction. In prior studies, the activation of IRF3 was shown to be mediated by cGAS-STING pathway. To investigate the contribution of STING to PLSCR1 induction, we utilized siRNA to reduce STING expression and observed that PLSCR1 protein was markedly reduced. In contrast to normal T80/HMECs, the phosphorylation of IRF3 as well as induction of STING and PLSCR1 were absent in ovarian cancer cells (serous, clear cell, and endometrioid suggesting that the STING/IRF3 pathway may be dysregulated in these cancer cells. However, we also noted induction of different TLR and IFN mRNAs between the T80 and HEY (serous epithelial ovarian carcinoma cell lines upon dsDNA transfection. Collectively, these results indicate that the STING/IRF3 pathway, activated following dsDNA transfection, contributes to upregulation of PLSCR1 in ovarian epithelial cells.

  6. Evaluation of potential regulatory elements identified as DNase I hypersensitive sites in the CFTR gene

    DEFF Research Database (Denmark)

    Phylactides, M.; Rowntree, R.; Nuthall, H.

    2002-01-01

    hypersensitive sites (DHS) within the locus. We previously identified at least 12 clusters of DHS across the CFTR gene and here further evaluate DHS in introns 2,3,10,16,17a, 18, 20 and 21 to assess their functional importance in regulation of CFTR gene expression. Transient transfections of enhancer/reporter...

  7. Development of a confocal ultrasound device using an inertial cavitation control for transfection in-vitro

    Science.gov (United States)

    Mestas, J. L.; Chettab, K.; Roux, S.; Prieur, F.; Lafond, M.; Dumontet, C.; Lafon, C.

    2015-12-01

    Sonoporation using low-frequency high-pressure ultrasound (US) is a non-viral approach for in vitro and in vivo gene delivery. We developed a new sonoporation device designed for spatial and temporal control of ultrasound cavitation. This device was evaluated for the in vitro transfection efficiency of a plasmid coding for Green Fluorescent Protein (peGFP- C1) in adherent and non-adherent cell lines. The frequency spectrum of the signal receive by a hydrophone is used to compute a cavitation index (CI) representative of the inertial cavitation activity. The influence of the CI on transfection efficiency, as well as reproducibility were determined. A real-time feedback loop control on CI was integrated in the process to regulate the cavitation level during sonoporation. In both adherent and non-adherent cell lines, the sonoporation device produced a highly efficient transfection of peGFP-C1 (40-80%), as determined by flow cytometry analysis of GFP expression, along with a low rate of mortality assessed by propidium iodide staining. Moreover, the sonoporation of non-adherent cell lines Jurkat and K562 was found to be equivalent to nucleofection in terms of efficiency and toxicity while these two cell lines were resistant to transfection with lipofection.

  8. Elevation of Transfection Efficiency by Conjugation of Poly(amindoamine)-diethylenetriamine (PAM-DET) with Dexamethasone

    International Nuclear Information System (INIS)

    Jeong, Yunseong; Park, Jihye; Jin, Geunwoo; Park, Jongsang

    2012-01-01

    We successfully conjugated hydrophobic group, dexamethasone onto the surface of PAM-DET to synthesize PAM-DET-DX to form polyplexes with enhanced stability against ionic strength. We evaluated its stability by measuring the size of its polyplexes; the conjugated PAM-DET polyplex showed decreased growth compared to the PAM-DET polyplex in an environment with increased ionic strength, which implies that the conjugated PAM-DET has enhanced stability against increased ionic strength. Furthermore, conjugation of hydrophobic group caused a slight increase in the transfection efficiency without inducing toxicity. Of course, it isn't a neglectable factor that nuclear localization effect of DX can drive the advanced transfection efficiency of PAM-DET-DX polyplex. It means that the hydrophobic moieties which have some other positive properties in transfection are good candidates that can be introduced to non-viral polymeric gene delivery carrier. This strongly indicates that the introduction of hydrophobic moiety on PAM-DET is a good method to enhance polyplex stability against ionic strength without diminishing its advantageous properties, such as high transfection efficiency and low cytotoxicity

  9. In vivo characterization of a reporter gene system for imaging hypoxia-induced gene expression.

    Science.gov (United States)

    Carlin, Sean; Pugachev, Andrei; Sun, Xiaorong; Burke, Sean; Claus, Filip; O'Donoghue, Joseph; Ling, C Clifton; Humm, John L

    2009-10-01

    To characterize a tumor model containing a hypoxia-inducible reporter gene and to demonstrate utility by comparison of reporter gene expression to the uptake and distribution of the hypoxia tracer (18)F-fluoromisonidazole ((18)F-FMISO). Three tumors derived from the rat prostate cancer cell line R3327-AT were grown in each of two rats as follows: (1) parental R3327-AT, (2) positive control R3327-AT/PC in which the HSV1-tkeGFP fusion reporter gene was expressed constitutively, (3) R3327-AT/HRE in which the reporter gene was placed under the control of a hypoxia-inducible factor-responsive promoter sequence (HRE). Animals were coadministered a hypoxia-specific marker (pimonidazole) and the reporter gene probe (124)I-2'-fluoro-2'-deoxy-1-beta-d-arabinofuranosyl-5-iodouracil ((124)I-FIAU) 3 h prior to sacrifice. Statistical analysis of the spatial association between (124)I-FIAU uptake and pimonidazole fluorescent staining intensity was then performed on a pixel-by-pixel basis. Utility of this system was demonstrated by assessment of reporter gene expression versus the exogenous hypoxia probe (18)F-FMISO. Two rats, each bearing a single R3327-AT/HRE tumor, were injected with (124)I-FIAU (3 h before sacrifice) and (18)F-FMISO (2 h before sacrifice). Statistical analysis of the spatial association between (18)F-FMISO and (124)I-FIAU on a pixel-by-pixel basis was performed. Correlation coefficients between (124)I-FIAU uptake and pimonidazole staining intensity were: 0.11 in R3327-AT tumors, -0.66 in R3327-AT/PC and 0.76 in R3327-AT/HRE, confirming that only in the R3327-AT/HRE tumor was HSV1-tkeGFP gene expression associated with hypoxia. Correlation coefficients between (18)F-FMISO and (124)I-FIAU uptakes in R3327-AT/HRE tumors were r=0.56, demonstrating good spatial correspondence between the two tracers. We have confirmed hypoxia-specific expression of the HSV1-tkeGFP fusion gene in the R3327-AT/HRE tumor model and demonstrated the utility of this model for the

  10. In vivo characterization of a reporter gene system for imaging hypoxia-induced gene expression

    International Nuclear Information System (INIS)

    Carlin, Sean; Pugachev, Andrei; Sun Xiaorong; Burke, Sean; Claus, Filip; O'Donoghue, Joseph; Ling, C. Clifton; Humm, John L.

    2009-01-01

    Purpose: To characterize a tumor model containing a hypoxia-inducible reporter gene and to demonstrate utility by comparison of reporter gene expression to the uptake and distribution of the hypoxia tracer 18 F-fluoromisonidazole ( 18 F-FMISO). Methods: Three tumors derived from the rat prostate cancer cell line R3327-AT were grown in each of two rats as follows: (1) parental R3327-AT, (2) positive control R3327-AT/PC in which the HSV1-tkeGFP fusion reporter gene was expressed constitutively, (3) R3327-AT/HRE in which the reporter gene was placed under the control of a hypoxia-inducible factor-responsive promoter sequence (HRE). Animals were coadministered a hypoxia-specific marker (pimonidazole) and the reporter gene probe 124 I-2'-fluoro-2'-deoxy-1-β-D-arabinofuranosyl-5-iodouracil ( 124 I-FIAU) 3 h prior to sacrifice. Statistical analysis of the spatial association between 124 I-FIAU uptake and pimonidazole fluorescent staining intensity was then performed on a pixel-by-pixel basis. Utility of this system was demonstrated by assessment of reporter gene expression versus the exogenous hypoxia probe 18 F-FMISO. Two rats, each bearing a single R3327-AT/HRE tumor, were injected with 124 I-FIAU (3 h before sacrifice) and 18 F-FMISO (2 h before sacrifice). Statistical analysis of the spatial association between 18 F-FMISO and 124 I-FIAU on a pixel-by-pixel basis was performed. Results: Correlation coefficients between 124 I-FIAU uptake and pimonidazole staining intensity were: 0.11 in R3327-AT tumors, -0.66 in R3327-AT/PC and 0.76 in R3327-AT/HRE, confirming that only in the R3327-AT/HRE tumor was HSV1-tkeGFP gene expression associated with hypoxia. Correlation coefficients between 18 F-FMISO and 124 I-FIAU uptakes in R3327-AT/HRE tumors were r=0.56, demonstrating good spatial correspondence between the two tracers. Conclusions: We have confirmed hypoxia-specific expression of the HSV1-tkeGFP fusion gene in the R3327-AT/HRE tumor model and demonstrated the utility of

  11. Enhanced transfection efficiency of human embryonic stem cells by the incorporation of DNA liposomes in extracellular matrix.

    Science.gov (United States)

    Villa-Diaz, Luis G; Garcia-Perez, Jose L; Krebsbach, Paul H

    2010-12-01

    Because human embryonic stem (hES) cells can differentiate into virtually any cell type in the human body, these cells hold promise for regenerative medicine. The genetic manipulation of hES cells will enhance our understanding of genes involved in early development and will accelerate their potential use and application for regenerative medicine. The objective of this study was to increase the transfection efficiency of plasmid DNA into hES cells by modifying a standard reverse transfection (RT) protocol of lipofection. We hypothesized that immobilization of plasmid DNA in extracellular matrix would be a more efficient method for plasmid transfer due to the affinity of hES cells for substrates such as Matrigel and to the prolonged exposure of cells to plasmid DNA. Our results demonstrate that this modification doubled the transfection efficiency of hES cells and the generation of clonal cell lines containing a piece of foreign DNA stably inserted in their genomes compared to results obtained with standard forward transfection. In addition, treatment with dimethyl sulfoxide further increased the transfection efficiency of hES cells. In conclusion, modifications to the RT protocol of lipofection result in a significant and robust increase in the transfection efficiency of hES cells.

  12. X-ray sensitive strains of CHO cells show decreased frequency of stable transfection

    International Nuclear Information System (INIS)

    Jeggo, P.; Smith, J.

    1987-01-01

    Six X-ray sensitive (xrs) strains of the Chinese hamster ovary cell line have previously been isolated and shown to have a defect in double strand break rejoining. In this study, these strains have been investigated for their ability to take up and integrate foreign DNA. All the xrs strains investigated so far have shown a decreased frequency of stable transfectants compared to their parent line, in experiments using the plasmid pSV2gpt, which contains the selectable bacterial gene, guanine phosphoribosyl transferase. This decreased frequency is observed over a wide range of DNA concentrations (0.1 to 20 μg DNA) but is more pronounced at higher DNA concentrations. In contrast, these xrs strains show the same level of transfection proficiency as the wild type parent using a transient transfection system with a plasmid containing the bacterial CAT (chloramphenicol acetyl transferase) gene. Since the level of CAT activity does not depend on integration of foreign DNA, this suggests that the xrs strains are able to take up the same amount of DNA as the parent strains, but have a defect in the integration of foreign DNA. Since this integration of foreign DNA probably occurs by non-homologous recombination, this may indicate a role of the xrs gene product in this process

  13. A trans-acting enhancer modulates estrogen-mediated transcription of reporter genes in osteoblasts.

    Science.gov (United States)

    Sasaki-Iwaoka, H; Maruyama, K; Endoh, H; Komori, T; Kato, S; Kawashima, H

    1999-02-01

    The presence of bone-specific estrogen agonists and discovery of the osteoblast-specific transcription factor (TF), Cbfa1, together with the discovery of synergism between a TF Pit-1 and estrogen receptor alpha (ERalpha) on rat prolactin gene, led to investigation of Cbfa1 in the modulation of osteoblast-specific actions of estrogen. Reverse transcribed-polymerase chain reaction demonstrated expression of Cbfa1 in the osteoblastic cell lines, MG63, ROS17/2.8, and MC3T3E1, but not in nonosteoblastic cell lines, MCF7, C3H10T1/2, and HeLa. An ER expression vector and a series of luciferase (Luc) reporter plasmids harboring the Cbfa1 binding site OSE2 (the osteoblast-specific cis element in the osteocalcin promoter) and palindromic estrogen response elements (EREs) were cotransfected into both osteoblastic and nonosteoblastic cells. OSE2 worked as a cis- acting element in osteoblastic cells but not nonosteoblastic cells, whereas EREs were cis- acting in all cell lines. Synergistic transactivation was observed in osteoblastic cells only when both ERE and OSE2 were placed in juxtaposition to the promoter. Forced expression of Cbfa1 in C3H10T1/2 cells also induced synergism. Tamoxifen, a partial agonist/antagonist of estrogen, acted as an osteoblast-specific agonist in cells transfected with a promoter containing ERE and acted synergistically with a promoter containing the ERE-OSE2 enhancer combination. These results support the idea that bone-specific TFs modulate the actions of estrogen in a tissue-specific manner.

  14. Complementation of the UV-sensitive phenotype of a xeroderma pigmentosum human cell line by transfection with a cDNA clone library

    International Nuclear Information System (INIS)

    Teitz, T.; Naiman, T.; Avissar, S.S.; Bar, S.; Okayama, H.; Canaani, D.

    1987-01-01

    In previous work, a xeroderma pigmentosum cell line belonging to complementation group C was established by transformation with origin-defective simian virus 40. We now report the complementation of the UV sensitivity of this cell line by gene transfer. A human cDNA clone library constructed in a mammalian expression vector, and itself incorporated in a lambda phage vector, was introduced into the cells as a calcium phosphate precipitate. Following selection to G418 resistance, provided by the neo gene of the vector, transformants were selected for UV resistance. Twenty-one cell clones were obtained with UV-resistance levels typical of normal human fibroblasts. All transformants contained vector DNA sequences in their nuclei. Upon further propagation in the absence of selection for G418 resistance, about half of the primary transformants remained UV-resistant. Secondary transformants were generated by transfection with a partial digest of total chromosomal DNA from one of these stable transformants. This resulted in 15 G418-resistant clones, 2 of which exhibited a UV-resistant phenotype. The other primary clones lost UV resistance rapidly when subcultured in the absence of G418. Importantly, several retained UV resistance under G418 selection pressure. The acquisition of UV resistance by secondary transformants derived by transfection of DNA from a stable primary transformant, and the linkage between G418 and UV resistances in the unstable primary transformants, strongly suggests that the transformants acquired UV resistance through DNA-mediated gene transfer and not by reversion

  15. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with SV40 T-antigen mutants defective in RB and P53 binding domains

    International Nuclear Information System (INIS)

    LingNah Su; Little, J.B.

    1992-01-01

    A series of human diploid fibroblast cell clones were developed by DNA transfection with either wild-type SV40 T-antigen (SV40T) or T-antigen mutants defective in its various functional domains. Cell clones expressing the wild-type SV40 T were significantly radioresistant as compared with clones transfected with the neo gene only (D o 192 ± 13 vs 127 ± 19). This radioresistance persisted in post-crisis, immortalized cell lines. A series of mutants with point or deletion mutations within each functionally active domain of SV40 T were also examined for their ability to alter radiosensitivity and induce morphological transformation. Cell clones transfected with T-antigen mutants defective in nuclear localization or origin binding showed increased radioresistance similar to clones transfected with wild-type T-antigen, and expressed morphological changes characteristic of SV40 T-transfected cells. (author)

  16. Mechanism of attenuation of a chimeric influenza A/B transfectant virus.

    Science.gov (United States)

    Luo, G; Bergmann, M; Garcia-Sastre, A; Palese, P

    1992-08-01

    The ribonucleoprotein transfection system for influenza virus allowed us to construct an influenza A virus containing a chimeric neuraminidase (NA) gene in which the noncoding sequence is derived from the NS gene of influenza B virus (T. Muster, E. K. Subbarao, M. Enami, B. P. Murphy, and P. Palese, Proc. Natl. Acad. Sci. USA 88:5177-5181, 1991). This transfectant virus is attenuated in mice and grows to lower titers in tissue culture than wild-type virus. Since such a virus has characteristics desirable for a live attenuated vaccine strain, attempts were made to characterize this virus at the molecular level. Our analysis suggests that the attenuation of the virus is due to changes in the cis signal sequences, which resulted in a reduction of transcription and replication of the chimeric NA gene. The major finding concerns a sixfold reduction in NA-specific viral RNA in the virion, causing a reduction in the ratio of infectious particles to physical particles compared with the ratio in wild-type virus. Although the NA-specific mRNA level is also reduced in transfectant virus-infected cells, it does not appear to contribute to the attenuation characteristics of the virus. The levels of the other RNAs and their expression appear to be unchanged for the transfectant virus. It is suggested that downregulation of the synthesis of one viral RNA segment leads to the generation of defective viruses during each replication cycle. We believe that this represents a general principle for attenuation which may be applied to other segmented viruses containing either single-stranded or double-stranded RNA.

  17. Infectious alphavirus production from a simple plasmid transfection+

    Directory of Open Access Journals (Sweden)

    Olson Ken E

    2011-07-01

    Full Text Available Abstract We have developed a new method for producing infectious double subgenomic alphaviruses from plasmids transfected into mammalian cells. A double subgenomic Sindbis virus (TE3'2J was transcribed from a cytomegalovirus PolII promoter, which results in the production of infectious virus. Transfection of as little as 125 ng of plasmid is able to produce 1 × 108 plaque forming units/ml (PFU/ml of infectious virus 48 hours post-transfection. This system represents a more efficient method for producing recombinant Sindbis viruses.

  18. In vivo imaging of induction of heat-shock protein-70 gene expression with fluorescence reflectance imaging and intravital confocal microscopy following brain ischaemia in reporter mice.

    Science.gov (United States)

    de la Rosa, Xavier; Santalucía, Tomàs; Fortin, Pierre-Yves; Purroy, Jesús; Calvo, Maria; Salas-Perdomo, Angélica; Justicia, Carles; Couillaud, Franck; Planas, Anna M

    2013-02-01

    Stroke induces strong expression of the 72-kDa heat-shock protein (HSP-70) in the ischaemic brain, and neuronal expression of HSP-70 is associated with the ischaemic penumbra. The aim of this study was to image induction of Hsp-70 gene expression in vivo after brain ischaemia using reporter mice. A genomic DNA sequence of the Hspa1b promoter was used to generate an Hsp70-mPlum far-red fluorescence reporter vector. The construct was tested in cellular systems (NIH3T3 mouse fibroblast cell line) by transient transfection and examining mPlum and Hsp-70 induction under a challenge. After construct validation, mPlum transgenic mice were generated. Focal brain ischaemia was induced by transient intraluminal occlusion of the middle cerebral artery and the mice were imaged in vivo with fluorescence reflectance imaging (FRI) with an intact skull, and with confocal microscopy after opening a cranial window. Cells transfected with the Hsp70-mPlum construct showed mPlum fluorescence after stimulation. One day after induction of ischaemia, reporter mice showed a FRI signal located in the HSP-70-positive zone within the ipsilateral hemisphere, as validated by immunohistochemistry. Live confocal microscopy allowed brain tissue to be visualized at the cellular level. mPlum fluorescence was observed in vivo in the ipsilateral cortex 1 day after induction of ischaemia in neurons, where it is compatible with penumbra and neuronal viability, and in blood vessels in the core of the infarction. This study showed in vivo induction of Hsp-70 gene expression in ischaemic brain using reporter mice. The fluorescence signal showed in vivo the induction of Hsp-70 in penumbra neurons and in the vasculature within the ischaemic core.

  19. A baculovirus (Bombyx mori nuclear polyhedrosis virus) repeat element functions as a powerful constitutive enhancer in transfected insect cells.

    Science.gov (United States)

    Lu, M; Farrell, P J; Johnson, R; Iatrou, K

    1997-12-05

    It has been previously reported that baculovirus homologous regions, the regions of baculovirus genomes that contain the origins of DNA replication, can augment the expression of a small number of baculovirus genes in vitro. We are now reporting that a region of the genome of Bombyx mori nuclear polyhedrosis virus (BmNPV) containing the homologous region 3 (HR3) acts as an enhancer for the promoter of a nonviral gene, the cytoplasmic actin gene of the silkmoth B. mori. Incorporation of the HR3 sequences of BmNPV into an actin promoter-based expression cassette results in an augmentation of transgene expression in transfected cells by two orders of magnitude relative to the control recombinant expression cassette. This increase is due to a corresponding increase in the rate of transcription from the actin promoter and not to replication of the expression cassette and occurs only when the HR3 element is linked to the expression cassette in cis. A comparable degree of enhancement in the activity of the silkworm actin promoter occurs also in heterologous lepidopteran cells. Concomitant supplementation of transfected cells with the BmIE1 trans-activator, which was previously shown to be capable of functioning in vitro as a transcriptional co-activator of the cytoplasmic actin gene promoter, results in more than a 1,000-fold increase in the level of expression of recombinant proteins placed under the control of the actin gene promoter. These findings provide the foundation for the development of a nonlytic insect cell expression system for continuous high-level expression of recombinant proteins. Such a system should provide levels of expression of recombinant proteins comparable to those obtained from baculovirus expression systems and should also have the additional advantage of continuous production in a cellular environment that, in contrast to that generated by a baculovirus infection, supports continuously proper posttranslational modifications of recombinant

  20. Upregulation of cellular glutathione levels in human ABCB5- and murine Abcb5-transfected cells.

    Science.gov (United States)

    Kondo, Shingo; Hongama, Keita; Hanaya, Kengo; Yoshida, Ryota; Kawanobe, Takaaki; Katayama, Kazuhiro; Noguchi, Kohji; Sugimoto, Yoshikazu

    2015-12-15

    Previously, we have demonstrated that human ABCB5 is a full-sized ATP-binding cassette transporter that shares strong homology with ABCB1/P-glycoprotein. ABCB5-transfected cells showed resistance to taxanes and anthracyclines. Herein, we further screened ABCB5 substrates, and explored the mechanism of resistance. Sensitivity of the cells to test compounds was evaluated using cell growth inhibition assay. Cellular levels of buthionine sulfoximine (BSO), glutathione and amino acids were measured using HPLC and an enzyme-based assay. Cellular and vesicular transport of glutathione was evaluated by a radiolabeled substrate. Expression levels of glutathione-metabolizing enzymes were assessed by RT-PCR. Human ABCB5-transfected 293/B5-11 cells and murine Abcb5-transfected 293/mb5-8 cells showed 6.5- and 14-fold higher resistance to BSO than the mock-transfected 293/mock cells, respectively. BSO is an inhibitor of gamma-glutamylcysteine ligase (GCL), which is a key enzyme of glutathione synthesis. 293/B5-11 and 293/mb5-8 cells also showed resistance to methionine sulfoximine, another GCL inhibitor. A cellular uptake experiment revealed that BSO accumulation in 293/B5-11 and 293/mb5-8 cells was similar to that in 293/mock cells, suggesting that BSO is not an ABCB5 substrate. The cellular glutathione content in 293/B5-11 and 293/mb5-8 cells was significantly higher than that in 293/mock cells. Evaluation of the BSO effect on the cellular glutathione content showed that compared with 293/mock cells the BSO concentration required for a 50 % reduction in glutathione content in 293/B5-11 and 293/mb5-8 cells was approximately 2- to 3-fold higher. This result suggests that the BSO resistance of the ABCB5- and Abcb5-transfected cells can be attributed to the reduced effect of BSO on the transfectants. Cellular and vesicular transport assays showed that the transport of radiolabeled glutathione in 293/B5-11 cells was similar to that in 293/mock cells. The mRNA expression of genes

  1. Experiment study of tyrosinase gene's expression in HEK293 cell by MR

    International Nuclear Information System (INIS)

    Yuan Jianpeng; Liang Biling; Zhong Jinglian; Xie Bangkun; Zhang Weidong; Zhang Lin

    2004-01-01

    Objective: To transfect the tyrosinase gene into HEK293 cell as a reporter gene, and to evaluate the tyrosinase gene's expression by using MRI based on the gene's property of synthesizing large amount of melanin, and to search a way for evaluating the results of gene expression by MR in vitro. Methods: The plasmid of pcDNA3tyr which carried the full-length cDNA of tyrosinase gene was transfected into HEK293 cell by lipofectin, and MR signals of expressed melanin was observed by scanning the transfected cells with MR sequences of T 1 WI, T 1 WI/SPIR, and T 2 WI. Fontana stain and electric microscopy were used to search for melanin granules in transfected cells, and RT-PCR method was used to search for cDNA of tyrosinase gene. Results: (1) Plasmids of pcDNA3tyr could be transfected into HEK293 cells and could synthesize a large amount of melanin in them. The synthetic melanin in 10 6 cells, which had been transfected with 5 μg, 10 μg, and 20 μg plasmids of pcDNA3tyr separately, were all sufficient to be detected by MR and appeared as high signal on MR T 1 WI, T 1 WI/SPIR, and T 2 WI sequences. The more the amounts of transfected plasmids, the higher the signal intensities of MR imaging. On the other hand, 6.25 x 10 4 cells with 20 μg-plasmid of pcDNA3tyr transfection could also be detected by MR; (2) The melanin granules could be found in HEK293 cells in Fontana stain; (3) The melanin granules and their front bodies could be found in intracytoplasm of HEK293 cell by electric microscopy. (4) The cDNA fragment of tyrosinase gene could be detected in transfected HEK293 cells by RT-PCR. Conclusion: The fact that MR could detect the synthetic melanin in HEK293 cells controlled by expression of exogenous gene demonstrated that medical imaging combined with molecular biology technology could evaluate the result of gene expression in vitro, and it also indicated that medical imaging could play an important role in the evaluation of gene therapy following the development

  2. siRNA Transfection and EMSA Analyses on Freshly Isolated Human Villous Cytotrophoblasts.

    Science.gov (United States)

    Lokossou, Adjimon Gatien; Toufaily, Chirine; Vargas, Amandine; Barbeau, Benoit

    2016-09-20

    Human primary villous cytotrophoblasts are a very useful source of primary cells to study placental functions and regulatory mechanisms, and to comprehend diseases related to pregnancy. In this protocol, human primary villous cytotrophoblasts freshly isolated from placentas through a standard DNase/trypsin protocol are microporated with small interfering RNA (siRNA). This approach provided greater efficiency for siRNA transfection when compared to a lipofection-based method. Transfected cells can subsequently be analyzed by standard Western blot within a time frame of 3-4 days post-transfection. In addition, using cultured primary villous cytotrophoblasts, Electrophoretic Mobility Shift Assay (EMSA) analysis was optimized and performed on extracts from days 1 to 4. The use of these cultured primary cells and the protocol described allow for an evaluation of the implication of specific genes and transcription factors in the process of villous cytotrophoblast differentiation into a syncytiotrophoblast-like cell layer. However, the limited time span allowable in culture precludes the use of methods requiring more time, such as generation of a stable cell population. Therefore testing of this cell population requires highly optimized gene transfer protocols.

  3. Ultrasound-targeted microbubble destruction enhances naked plasmid DNA transfection in rabbit Achilles tendons in vivo.

    Science.gov (United States)

    Qiu, L; Zhang, L; Wang, L; Jiang, Y; Luo, Y; Peng, Y; Lin, L

    2012-07-01

    The study was to investigate the probability of increasing the transfection of the gene in tendons by ultrasound-targeted microbubble destruction (UTMD), and to search for the most suitable transfection conditions. A mixture of microbubbles and enhanced green fluorescent protein (EGFP) plasmids was injected into rabbit Achilles tendons by different administration routes and the tendons were ultrasound pulse by different ultrasonic conditions in order to determine the most appropriate conditions. Then, the rabbits were divided into four groups: (1) ultrasound + microbubbles + plasmid; (2) ultrasound+ plasmid; (3) microbubble + plasmid; (4) plasmid only. EGFP expression in the tendons and other tissues, and the damage to tendon and paratenon were all observed. The results showed that EGFP expression in the tendon was higher by ultrasound pulse with 2 W cm(-2) of output intensity and a 20% duty cycle for 10 min. Local injection was determined to be the better administration route. Among the four groups, EGFP expression in Group 1 was higher than that in other groups. EGFP expression was highest on seventh day, then it gradually decrease over time, and lasted more than 56 days. EGFP expression was not found in other tissues. There was no obvious injury caused by UTMD. Under suitable conditions, it is feasible to use UTMD as a safe and effective gene transfection therapy for tendon injuries.

  4. Structural mediation on polycation nanoparticles by sulfadiazine to enhance DNA transfection efficiency and reduce toxicity.

    Science.gov (United States)

    Long, Xingwen; Zhang, Zhihui; Han, Shangcong; Tang, Minjie; Zhou, Junhui; Zhang, Jianhua; Xue, Zhenyi; Li, Yan; Zhang, Rongxin; Deng, Liandong; Dong, Anjie

    2015-04-15

    Reducing the toxicity while maintaining high transfection efficiency is an important issue for cationic polymers as gene carriers in clinical application. In this paper, a new zwitterionic copolymer, polycaprolactone-g-poly(dimethylaminoethyl methyacrylate-co-sulfadiazine methacrylate) (PC-SDZ) with unique pH-sensitivity, was designed and prepared. The incorporation of sulfadiazine into poly(dimethylaminoethyl methacrylate) (PDMAEMA) chains successfully mediates the surface properties including compacter shell structure, lower density of positive charges, stronger proton buffer capability, and enhanced hydrophobicity, which lead to reduction in toxicity and enhancements in stability, cellular uptake, endosome escape, and transfection efficiency for the PC-SDZ2 nanoparticles (NPs)/DNA complexes. Excellent transfection efficiency at the optimal N/P ratio of 10 was observed for PC-SDZ2 NPs/DNA complexes, which was higher than that of the commercial reagent-branched polyethylenimine (PEI). The cytotoxicity was evaluated by CCK8 measurement, and the results showed significant reduction in cytotoxicity even at high concentration of complexes after sulfadiazine modification. Therefore, this work may demonstrate a new way of structural mediation of cationic polymer carriers for gene delivery with high efficiency and low toxicity.

  5. Horizontal gene transfer from macrophages to ischemic muscles upon delivery of naked DNA with Pluronic block copolymers.

    Science.gov (United States)

    Mahajan, Vivek; Gaymalov, Zagit; Alakhova, Daria; Gupta, Richa; Zucker, Irving H; Kabanov, Alexander V

    2016-01-01

    Intramuscular administration of plasmid DNA (pDNA) with non-ionic Pluronic block copolymers increases gene expression in injected muscles and lymphoid organs. We studied the role of immune cells in muscle transfection upon inflammation. Local inflammation in murine hind limb ischemia model (MHLIM) drastically increased DNA, RNA and expressed protein levels in ischemic muscles injected with pDNA/Pluronic. The systemic inflammation (MHLIM or peritonitis) also increased expression of pDNA/Pluronic in the muscles. When pDNA/Pluronic was injected in ischemic muscles the reporter gene, Green Fluorescent Protein (GFP) co-localized with desmin(+) muscle fibers and CD11b(+) macrophages (MØs), suggesting transfection of MØs along with the muscle cells. P85 enhanced (∼ 4 orders) transfection of MØs with pDNA in vitro. Moreover, adoptively transferred MØs were shown to pass the transgene to inflamed muscle cells in MHLIM. Using a co-culture of myotubes (MTs) and transfected MØs expressing a reporter gene under constitutive (cmv-luciferase) or muscle specific (desmin-luciferase) promoter we demonstrated that P85 enhances horizontal gene transfer from MØ to MTs. Therefore, MØs can play an important role in muscle transfection with pDNA/Pluronic during inflammation, with both inflammation and Pluronic contributing to the increased gene expression. pDNA/Pluronic has potential for therapeutic gene delivery in muscle pathologies that involve inflammation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Optimizing the transient transfection process of HEK-293 suspension cells for protein production by nucleotide ratio monitoring

    DEFF Research Database (Denmark)

    de Los Milagros Bassani Molinas, Maria; Beer, Christiane; Hesse, F

    2014-01-01

    Large scale, transient gene expression (TGE) is highly dependent of the physiological status of a cell line. Therefore, intracellular nucleotide pools and ratios were used for identifying and monitoring the optimal status of a suspension cell line used for TGE. The transfection efficiency upon po...

  7. DyNAvectors: dynamic constitutional vectors for adaptive DNA transfection.

    Science.gov (United States)

    Clima, Lilia; Peptanariu, Dragos; Pinteala, Mariana; Salic, Adrian; Barboiu, Mihail

    2015-12-25

    Dynamic constitutional frameworks, based on squalene, PEG and PEI components, reversibly connected to core centers, allow the efficient identification of adaptive vectors for good DNA transfection efficiency and are well tolerated by mammalian cells.

  8. Reconstructing Dynamic Promoter Activity Profiles from Reporter Gene Data.

    Science.gov (United States)

    Kannan, Soumya; Sams, Thomas; Maury, Jérôme; Workman, Christopher T

    2018-03-16

    Accurate characterization of promoter activity is important when designing expression systems for systems biology and metabolic engineering applications. Promoters that respond to changes in the environment enable the dynamic control of gene expression without the necessity of inducer compounds, for example. However, the dynamic nature of these processes poses challenges for estimating promoter activity. Most experimental approaches utilize reporter gene expression to estimate promoter activity. Typically the reporter gene encodes a fluorescent protein that is used to infer a constant promoter activity despite the fact that the observed output may be dynamic and is a number of steps away from the transcription process. In fact, some promoters that are often thought of as constitutive can show changes in activity when growth conditions change. For these reasons, we have developed a system of ordinary differential equations for estimating dynamic promoter activity for promoters that change their activity in response to the environment that is robust to noise and changes in growth rate. Our approach, inference of dynamic promoter activity (PromAct), improves on existing methods by more accurately inferring known promoter activity profiles. This method is also capable of estimating the correct scale of promoter activity and can be applied to quantitative data sets to estimate quantitative rates.

  9. Efficient transfection of primarily cultured porcine embryonic fibroblasts using the Amaxa Nucleofection system.

    Science.gov (United States)

    Nakayama, Asuka; Sato, Masahiro; Shinohara, Mariko; Matsubara, Shyuichiro; Yokomine, Takaaki; Akasaka, Eri; Yoshida, Mitsutoshi; Takao, Sonshin

    2007-01-01

    Porcine embryonic fibroblasts (PEF) are important as donor cells for nuclear transfer for generation of genetically modified pigs. In this study, we determined an optimal protocol for transfection of PEF with the Amaxa Nucleofection system, which directly transfers DNA into the nucleus of cells, and compared its efficiency with conventional lipofection and electroporation. Cell survival and transfection efficiency were assessed using dye-exclusion assay and a green fluorescent protein (GFP) reporter construct, respectively. Our optimized nucleofection parameters yielded survival rates above 60%. Under these conditions, FACS analysis demonstrated that 79% of surviving cells exhibited transgene expression 48 h after nucleofection when program U23 was used. This efficiency was higher than that of transfection of PEFs with electroporation (ca. 3-53%) or lipofection (ca. 3-8%). Transfected cells could be expanded as stably transgene-expressing clones over a month. When porcine nuclear transfer (NT) was performed using stable transformant expressing GFP as a donor cell, 5-6% of reconstituted embryos developed to blastocysts, from which 30-50% of embryos exhibited NT-embryo-derived green fluorescence. Under the conditions evaluated, nucleofection exhibited higher efficiency than conventional electroporation and lipofection, and may be a useful alternative for generation of genetically engineered pigs through nuclear transfer.

  10. Flow-through electroporation based on constant voltage for large-volume transfection of cells.

    Science.gov (United States)

    Geng, Tao; Zhan, Yihong; Wang, Hsiang-Yu; Witting, Scott R; Cornetta, Kenneth G; Lu, Chang

    2010-05-21

    Genetic modification of cells is a critical step involved in many cell therapy and gene therapy protocols. In these applications, cell samples of large volume (10(8)-10(9)cells) are often processed for transfection. This poses new challenges for current transfection methods and practices. Here we present a novel flow-through electroporation method for delivery of genes into cells at high flow rates (up to approximately 20 mL/min) based on disposable microfluidic chips, a syringe pump, and a low-cost direct current (DC) power supply that provides a constant voltage. By eliminating pulse generators used in conventional electroporation, we dramatically lowered the cost of the apparatus and improved the stability and consistency of the electroporation field for long-time operation. We tested the delivery of pEFGP-C1 plasmids encoding enhanced green fluorescent protein into Chinese hamster ovary (CHO-K1) cells in the devices of various dimensions and geometries. Cells were mixed with plasmids and then flowed through a fluidic channel continuously while a constant voltage was established across the device. Together with the applied voltage, the geometry and dimensions of the fluidic channel determined the electrical parameters of the electroporation. With the optimal design, approximately 75% of the viable CHO cells were transfected after the procedure. We also generalize the guidelines for scaling up these flow-through electroporation devices. We envision that this technique will serve as a generic and low-cost tool for a variety of clinical applications requiring large volume of transfected cells. Copyright 2010 Elsevier B.V. All rights reserved.

  11. hNIS-IRES-eGFP Dual Reporter Gene Imaging

    Directory of Open Access Journals (Sweden)

    Jiantu Che

    2005-04-01

    Full Text Available The human and rodent sodium iodide symporters (NIS have recently been cloned and are being investigated as potential therapeutic and reporter genes. We have extended this effort by constructing an internal ribosomal entry site (IRES-linked human NIS (hNIS-enhanced green fluorescent protein (eGFP hybrid reporter gene for both nuclear and optical imaging. A self-inactivating retroviral vector, termed pQCNIG, containing hNIS-IRES-eGFP dual reporter gene, driven by a constitutive CMV promoter, was constructed and used to generate RG2-pQCNIG cells and RG2-pQCNIG tumors. 131I-iodide and 99mTcO4-pertechnetate accumulation studies plus fluorescence microscopy and intensity assays were performed in vitro, and gamma camera imaging studies in RG2-pQCNIG and RG2 tumor-bearing athymic rats were performed. RG2-pQCNIG cells expressed high levels of hNIS protein and showed high intensity of eGFP fluorescence compared with RG2 wild-type cells. RG2-pQCNIG cells accumulated Na131I and 99mTcO4– to a 50:1 and a 170:1 tissue/medium ratio at 10 min, compared with 0.8:1.2 tissue/medium ratio in wild-type RG2 cells. A significant correlation between radiotracer accumulation and eGFP fluorescence intensity was demonstrated. RG2-pQCNIG and RG2 tumors were readily differentiated by in vivo gamma camera imaging; radiotracer uptake increased in RG2-pQCNIG but declined in RG2 tumors over the 50-min imaging period. Stomach and thyroid were the major organs of radionuclide accumulation. The IRES-linked hNIS-eGFP dual reporter gene is functional and stable in transduced RG2-pQCNIG cells. Optical and nuclear imaging of tumors produced from these cell lines provides the opportunity to monitor tumor growth and response to therapy. These studies indicate the potential for a wider application of hNIS reporter imaging and translation into patient studies using radioisotopes that are currently available for human use for both SPECT and PET imaging.

  12. Multimodality imaging of reporter gene expression using a novel fusion vector in living cells and animals

    Science.gov (United States)

    Gambhir, Sanjiv [Portola Valley, CA; Pritha, Ray [Mountain View, CA

    2011-06-07

    Novel double and triple fusion reporter gene constructs harboring distinct imagable reporter genes are provided, as well as applications for the use of such double and triple fusion constructs in living cells and in living animals using distinct imaging technologies.

  13. Adenovirus-assisted lipofection: efficient in vitro gene transfer of luciferase and cytosine deaminase to human smooth muscle cells.

    Science.gov (United States)

    Kreuzer, J; Denger, S; Reifers, F; Beisel, C; Haack, K; Gebert, J; Kübler, W

    1996-07-01

    Smooth muscle cells (SMC) are a central cell type involved in multiple processes of coronary artery diseases including restenosis and therefore are major target cells for different aspects of gene transfer. Previous attempts to transfect primary arterial cells using different techniques like liposomes, CaPO4 and electroporation resulted in only low transfection efficiency. The development of recombinant adenoviruses dramatically improved the delivery of foreign genes into different cell types including SMC. However, cloning and identification of recombinants remain difficult and time-consuming techniques. The present study demonstrates that a complex consisting of reporter plasmid encoding firefly luciferase (pLUC), polycationic liposomes and replication-deficient adenovirus was able to yield very high in vitro transfection of primary human smooth muscle cells under optimized conditions. The technique of adenovirus-assisted lipofection (AAL) increases transfer and expression of plasmid DNA in human smooth muscle cells in vitro up to 1000-fold compared to lipofection. To verify the applicability of AAL for gene transfer into human smooth muscle cells we studied a gene therapy approach to suppress proliferation of SMC in vitro, using the prokaryotic cytosine deaminase gene (CD) which enables transfected mammalian cells to deaminate 5-fluorocytosine (5-FC) to the highly toxic 5-fluorouracil (5-FU). The effect of a transient CD expression on RNA synthesis was investigated by means of a cotransfection with a RSV-CD expression plasmid and the luciferase reporter plasmid. Western blot analysis demonstrated high expression of CD protein in transfected SMC. Cotransfected SMC demonstrated two-fold less luciferase activity in the presence of 5-FC (5 mmol/l) after 48 h compared to cells transfected with a non-CD coding plasmid. The data demonstrate that a transient expression of CD could be sufficient to reduce the capacity of protein synthesis in human SMC. This simple and

  14. Transfection of Babesia bovis by Double Selection with WR99210 and Blasticidin-S and Its Application for Functional Analysis of Thioredoxin Peroxidase-1.

    Directory of Open Access Journals (Sweden)

    Masahito Asada

    Full Text Available Genetic manipulation is an essential technique to analyze gene function; however, limited methods are available for Babesia bovis, a causative pathogen of the globally important cattle disease, bovine babesiosis. To date, two stable transfection systems have been developed for B. bovis, using selectable markers blasticidin-S deaminase (bsd or human dihydrofolate reductase (hdhfr. In this work, we combine these two selectable markers in a sequential transfection system. Specifically, a parent transgenic B. bovis line which episomally expresses green fluorescent protein (GFP and human dihydrofolate reductase (hDHFR, was transfected with a plasmid encoding a fusion protein consisting of red fluorescent protein (RFP and blasticidin-S deaminase (BSD. Selection with WR99210 and blasticidin-S resulted in the emergence of parasites double positive for GFP and RFP. We then applied this method to complement gene function in a parasite line in which thioredoxin peroxidase-1 (Bbtpx-1 gene was knocked out using hDHFR as a selectable marker. A plasmid was constructed harboring both RFP-BSD and Bbtpx-1 expression cassettes, and transfected into a Bbtpx-1 knockout (KO parasite. Transfectants were independently obtained by two transfection methods, episomal transfection and genome integration. Complementation of Bbtpx-1 resulted in full recovery of resistance to nitrosative stress, via the nitric oxide donor sodium nitroprusside, which was impaired in the Bbtpx-1 KO parasites. In conclusion, we developed a sequential transfection method in B. bovis and subsequently applied this technique in a gene complementation study. This method will enable broader genetic manipulation of Babesia toward enhancing our understanding of the biology of this parasite.

  15. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated RAS oncogene and SV40 T-antigen

    Energy Technology Data Exchange (ETDEWEB)

    Su, L.-N.; Little, J.B. (Harvard School of Public Health, Boston, MA (United States))

    1992-08-01

    Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself. (author).

  16. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated RAS oncogene and SV40 T-antigen

    International Nuclear Information System (INIS)

    Su, L.-N.; Little, J.B.

    1992-01-01

    Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself. (author)

  17. Cationic Phospholipids Forming Cubic Phases: Lipoplex Structure and Transfection Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Koynova, Rumiana; Wang, Li; MacDonald, Robert C. (NWU)

    2008-10-29

    The transfection activity and the phase behavior of two novel cationic O-alkyl-phosphatidylcholines, 1,2-dioleoyl-sn-glycero-3-hexylphosphocholine (C6-DOPC) and 1,2-dierucoyl-sn-glycero-3-ethylphosphocholine (di22:1-EPC), have been examined with the aim of more completely understanding the mechanism of lipid-mediated DNA delivery. Both lipids form cubic phases: C6-DOPC in the entire temperature range from -10 to 90 C, while di22:1-EPC exhibits an irreversible lamellar-cubic transition between 50 and 70 C on heating. The lipoplexes formed by C6-DOPC arrange into hexagonal phase, while the lipoplexes of di22:1-EPC are lamellar. Both lipids exhibit lower transfection activity than the lamellar-forming 1,2-dioleoyl-sn-glycero-3-ethylphosphocholine (EDOPC). Thus, for the studied cationic phospholipid-DNA systems, the lipoplex phase state is a factor that does not seem to correlate with transfection activity. The parameter that exhibits better correlation with the transfection activity within the present data set is the phase state of the lipid dispersion prior to the addition of DNA. Thus, the lamellar lipid dispersion (EDOPC) produces more efficient lipoplexes than the dispersion with coexisting lamellar and cubic aggregates (diC22:1-EPC), which is even more efficient than the purely cubic dispersions (C6-DOPC; diC22:1-EPC after heating). It could be inferred from these data and from previous research that cubic phase lipid aggregates are unlikely to be beneficial to transfection. The lack of correlation between the phase state of lipoplexes and their transfection activity observed within the present data set does not mean that lipid phase state is generally unimportant for lipofection: a viewpoint now emerging from our previous studies is that the critical factor in lipid-mediated transfection is the structural evolution of lipoplexes within the cell, upon interacting and mixing with cellular lipids.

  18. Cationic phospholipids forming cubic phases: lipoplex structure and transfection efficiency.

    Science.gov (United States)

    Koynova, Rumiana; Wang, Li; Macdonald, Robert C

    2008-01-01

    The transfection activity and the phase behavior of two novel cationic O-alkyl-phosphatidylcholines, 1,2-dioleoyl- sn-glycero-3-hexylphosphocholine (C6-DOPC) and 1,2-dierucoyl- sn-glycero-3-ethylphosphocholine (di22:1-EPC), have been examined with the aim of more completely understanding the mechanism of lipid-mediated DNA delivery. Both lipids form cubic phases: C6-DOPC in the entire temperature range from -10 to 90 degrees C, while di22:1-EPC exhibits an irreversible lamellar-cubic transition between 50 and 70 degrees C on heating. The lipoplexes formed by C6-DOPC arrange into hexagonal phase, while the lipoplexes of di22:1-EPC are lamellar. Both lipids exhibit lower transfection activity than the lamellar-forming 1,2-dioleoyl- sn-glycero-3-ethylphosphocholine (EDOPC). Thus, for the studied cationic phospholipid-DNA systems, the lipoplex phase state is a factor that does not seem to correlate with transfection activity. The parameter that exhibits better correlation with the transfection activity within the present data set is the phase state of the lipid dispersion prior to the addition of DNA. Thus, the lamellar lipid dispersion (EDOPC) produces more efficient lipoplexes than the dispersion with coexisting lamellar and cubic aggregates (diC22:1-EPC), which is even more efficient than the purely cubic dispersions (C6-DOPC; diC22:1-EPC after heating). It could be inferred from these data and from previous research that cubic phase lipid aggregates are unlikely to be beneficial to transfection. The lack of correlation between the phase state of lipoplexes and their transfection activity observed within the present data set does not mean that lipid phase state is generally unimportant for lipofection: a viewpoint now emerging from our previous studies is that the critical factor in lipid-mediated transfection is the structural evolution of lipoplexes within the cell, upon interacting and mixing with cellular lipids.

  19. Transformation and radiosensitivity of human diploid skin fibroblasts transfected with activated ras oncogene and SV40 T-antigen.

    Science.gov (United States)

    Su, L N; Little, J B

    1992-08-01

    Three normal human diploid cell strains were transfected with an activated Ha-ras oncogene (EJ ras) or SV40 T-antigen. Multiple clones were examined for morphological alterations, growth requirements, ability to grow under anchorage independent conditions, immortality and tumorigenicity in nude mice. Clones expressing SV40 T-antigen alone or in combination with ras protein p21 were significantly radioresistant as compared with their parent cells or clones transfected with the neo gene only. This radioresistant phenotype persisted in post-crisis, immortalized cell lines. Cells transfected with EJ ras alone showed no morphological alterations nor significant changes in radiosensitivity. Cell clones expressing ras and/or SV40 T-antigen showed a reduced requirement for serum supplements, an increase in aneuploidy and chromosomal aberrations, and enhanced growth in soft agar as an early cellular response to SV40 T-antigen expression. The sequential order of transfection with SV40 T-antigen and ras influenced radio-sensitivity but not the induction of morphological changes. These data suggest that expression of the SV40 T-antigen but not activated Ha-ras plays an important role in the radiosensitivity of human diploid cells. The radioresistant phenotype in SV40 T transfected cells was not related to the enhanced level of genetic instability seen in pre-crisis and newly immortalized cells, nor to the process of immortalization itself.

  20. A Novel ‘Gene Insertion/Marker Out’ (GIMO) Method for Transgene Expression and Gene Complementation in Rodent Malaria Parasites

    Science.gov (United States)

    Sajid, Mohammed; Chevalley-Maurel, Séverine; Ramesar, Jai; Klop, Onny; Franke-Fayard, Blandine M. D.; Janse, Chris J.; Khan, Shahid M.

    2011-01-01

    Research on the biology of malaria parasites has greatly benefited from the application of reverse genetic technologies, in particular through the analysis of gene deletion mutants and studies on transgenic parasites that express heterologous or mutated proteins. However, transfection in Plasmodium is limited by the paucity of drug-selectable markers that hampers subsequent genetic modification of the same mutant. We report the development of a novel ‘gene insertion/marker out’ (GIMO) method for two rodent malaria parasites, which uses negative selection to rapidly generate transgenic mutants ready for subsequent modifications. We have created reference mother lines for both P. berghei ANKA and P. yoelii 17XNL that serve as recipient parasites for GIMO-transfection. Compared to existing protocols GIMO-transfection greatly simplifies and speeds up the generation of mutants expressing heterologous proteins, free of drug-resistance genes, and requires far fewer laboratory animals. In addition we demonstrate that GIMO-transfection is also a simple and fast method for genetic complementation of mutants with a gene deletion or mutation. The implementation of GIMO-transfection procedures should greatly enhance Plasmodium reverse-genetic research. PMID:22216235

  1. In vitro expression of erythropoietin by transfected human mesenchymal stromal cells.

    Science.gov (United States)

    Mok, P-L; Cheong, S-K; Leong, C-F; Othman, A

    2008-01-01

    Mesenchymal stromal cells (MSC) are pluripotent progenitor cells that can be found in human bone marrow (BM). These cells have low immunogenicity and could suppress alloreactive T-cell responses. In the current study, MSC were tested for their capacity to carry and deliver the erythropoietin (EPO) gene in vitro. Expanded BM MSC was transfected with EPO-encoded plasmid pMCV1.2 and EPO-encoded MIDGE (minimalistic immunologically defined gene expression) vector by electroporation. The expressed EPO was used to induce hematopoietic stem cells (HSC) into erythroid colonies. The results showed that the MIDGE vector was more effective and stable than the plasmid (pMCV1.2) in delivering EPO gene into MSC. The supernatants containing EPO obtained from the transfected cell culture were able to induce the differentiation of HSC into erythroid colonies. MSC hold promise as a cell factory for the production of biologic molecules, and MIDGE vector is more effective and stable than the plasmid in nucleofection involving the EPO gene.

  2. Endocrine disruptive effects of chemicals eluted from nitrile-butadiene rubber gloves using reporter gene assay systems.

    Science.gov (United States)

    Satoh, Kanako; Nonaka, Ryouichi; Ohyama, Ken-ichi; Nagai, Fumiko; Ogata, Akio; Iida, Mitsuru

    2008-03-01

    Disposable gloves made of nitrile-butadiene rubber (NBR) are used for contact with foodstuffs rather than polyvinyl chloride gloves containing di(2-ethylhexyl)phthalate (DEHP), because endocrine-disruptive effects are suspected for phthalate diesters including DEHP. However, 4,4'-butylidenebis(6-t-butyl-m-cresol) (BBBC), 2,4-di-t-butylphenol, and 2,2,4-trimetyl-1,3-pentanediol diisobutyrate can be eluted from NBR gloves, and possibly also detected in food. In this study, we examined the endocrine-disrupting effects of these chemicals via androgen receptor (AR) and estrogen receptor (ER)-mediated pathways using stably transfected reporter gene cell lines expressing AR (AR-EcoScreen system) and ER (MVLN cells), respectively. We also examined the binding activities of these chemicals to AR and ER. The IC50 value of BBBC for antagonistic androgen was in the range of 10(-6)M. The strength of inhibition was about 5 times that of a known androgen antagonist, 1,1'-(2,2-dichloroethylidene)bis[4-chlorobenzene] (p,p'-DDE), and similar to that of bisphenol A. The IC50 value of BBBC for antagonistic estrogen was in the range of 10(-6)M. These results suggest that BBBC and its structural homologue, 4,4'-thiobis(6-t-butyl-m-cresol) are androgen and estrogen antagonists. It is therefore necessary to study these chemicals in vivo, and clarify their effect on the endocrine system.

  3. Nucleofection: A New Method for Cutaneous Gene Transfer?

    Directory of Open Access Journals (Sweden)

    Frank Jacobsen

    2006-01-01

    Full Text Available Background. Transfection efficacy after nonviral gene transfer in primary epithelial cells is limited. The aim of this study was to compare transfection efficacy of the recently available method of nucleofection with the established transfection reagent FuGENE6. Methods. Primary human keratinocytes (HKC, primary human fibroblasts (HFB, and a human keratinocyte cell line (HaCaT were transfected with reporter gene construct by FuGENE6 or Amaxa Nucleofector device. At corresponding time points, β-galactosidase expression, cell proliferation (MTT-Test, transduction efficiency (X-gal staining, cell morphology, and cytotoxicity (CASY were determined. Results. Transgene expression after nucleofection was significantly higher in HKC and HFB and detected earlier (3 h vs. 24 h than in FuGENE6. After lipofection 80%–90% of the cells remained proliferative without any influence on cell morphology. In contrast, nucleofection led to a decrease in keratinocyte cell size, with only 20%–42% proliferative cells. Conclusion. Related to the method-dependent increase of cytotoxicity, transgene expression after nucleofection was earlier and higher than after lipofection.

  4. Nucleofection: A New Method for Cutaneous Gene Transfer?

    Science.gov (United States)

    Jacobsen, Frank; Mertens-Rill, Janine; Beller, Juergen; Hirsch, Tobias; Daigeler, Adrien; Langer, Stefan; Lehnhardt, Marcus; Steinau, Hans-Ulrich; Steinstraesser, Lars

    2006-01-01

    Background. Transfection efficacy after nonviral gene transfer in primary epithelial cells is limited. The aim of this study was to compare transfection efficacy of the recently available method of nucleofection with the established transfection reagent FuGENE6. Methods. Primary human keratinocytes (HKC), primary human fibroblasts (HFB), and a human keratinocyte cell line (HaCaT) were transfected with reporter gene construct by FuGENE6 or Amaxa Nucleofector device. At corresponding time points, β-galactosidase expression, cell proliferation (MTT-Test), transduction efficiency (X-gal staining), cell morphology, and cytotoxicity (CASY) were determined. Results. Transgene expression after nucleofection was significantly higher in HKC and HFB and detected earlier (3 h vs. 24 h) than in FuGENE6. After lipofection 80%–90% of the cells remained proliferative without any influence on cell morphology. In contrast, nucleofection led to a decrease in keratinocyte cell size, with only 20%–42% proliferative cells. Conclusion. Related to the method-dependent increase of cytotoxicity, transgene expression after nucleofection was earlier and higher than after lipofection. PMID:17489014

  5. Femtosecond laser assisted photo-transfection and differentiation of mouse embryonic stem cells

    Science.gov (United States)

    Thobakgale, Lebogang; Manoto, Sello; Ombinda Lemboumba, Satuurnin; Maaza, Malik; Mthunzi-Kufa, Patience

    2018-02-01

    In tissue engineering research, stem cells have been used as starting material in the synthesis of mammalian cells for the treatment of various cell based diseases. This is done by manipulating the DNA content of the cells to induce a specific effect such as increased proliferation or developing a new cell type through the process of differentiation. Such controlled gene expression of stem cells is achieved by the method of transfection, where exogenous plasmid deoxyribonucleic acid (pDNA) is inserted into a stem cell using chemical, viral or physical methods. In this research, we used femtosecond (fs) laser pulses from a home-build microscope system to perforate the cellular membrane and allow entry of selected pDNA to alter the behaviour of mouse embryonic stem cells (mESCs). In one set of experiments, we induce fluorescence on mESCs using green fluorescence protein plasmid (pGFP) while in other tests; differentiation of mESCs into endoderm cells is performed using Sox-17 plasmid DNA (pSox-17). Primitive endoderm formation was thereafter confirmed using polymerase chain reactions (PCR) and the Sox-17 primer. Cell viability studies using adenosine triphosphate were also conducted. From the data, it was concluded that the photo-transfection method is biocompatible since it was able to induce fluorescence in mESCs. Secondly, it was confirmed that Sox-17 was photo-transfected successfully using 6 μW laser power, 128 fs pulses and 1kHz pulse repetition rate.

  6. Single-cell mRNA transfection studies: delivery, kinetics and statistics by numbers.

    Science.gov (United States)

    Leonhardt, Carolin; Schwake, Gerlinde; Stögbauer, Tobias R; Rappl, Susanne; Kuhr, Jan-Timm; Ligon, Thomas S; Rädler, Joachim O

    2014-05-01

    In artificial gene delivery, messenger RNA (mRNA) is an attractive alternative to plasmid DNA (pDNA) since it does not require transfer into the cell nucleus. Here we show that, unlike for pDNA transfection, the delivery statistics and dynamics of mRNA-mediated expression are generic and predictable in terms of mathematical modeling. We measured the single-cell expression time-courses and levels of enhanced green fluorescent protein (eGFP) using time-lapse microscopy and flow cytometry (FC). The single-cell analysis provides direct access to the distribution of onset times, life times and expression rates of mRNA and eGFP. We introduce a two-step stochastic delivery model that reproduces the number distribution of successfully delivered and translated mRNA molecules and thereby the dose-response relation. Our results establish a statistical framework for mRNA transfection and as such should advance the development of RNA carriers and small interfering/micro RNA-based drugs. This team of authors established a statistical framework for mRNA transfection by using a two-step stochastic delivery model that reproduces the number distribution of successfully delivered and translated mRNA molecules and thereby their dose-response relation. This study establishes a nice connection between theory and experimental planning and will aid the cellular delivery of mRNA molecules. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Transfection of mouse cytotoxic T lymphocyte with an antisense granzyme A vector reduces lytic activity.

    Science.gov (United States)

    Talento, A; Nguyen, M; Law, S; Wu, J K; Poe, M; Blake, J T; Patel, M; Wu, T J; Manyak, C L; Silberklang, M

    1992-12-15

    Murine CTL have seven serine proteases, known as granzymes, in their lytic granules. Despite considerable effort, convincing evidence that these enzymes play an obligatory role in the lytic process has not been presented. To investigate the function of one of these proteases, granzyme A (GA), we utilized an antisense expression vector to lower the level of the enzyme in the cells. An expression vector containing antisense cDNA for GA and the gene for hygromycin B resistance was constructed and electroporated into the murine CTL line, AR1. Transfectants were selected based on resistance to hygromycin B, and a number of stable lines were developed. One of the antisense lines had greatly reduced levels of GA mRNA, when compared to the parental cells or to control lines transfected with the vector lacking the antisense DNA. The message levels for two other CTL granule proteins, granzyme B and perforin, were unaffected by the antisense vector. The amount of GA, as measured by enzymatic activity, was 3- to 10-fold lower in the transfectant. Most significantly, this line also consistently showed 50 to 70% lower ability to lyse nucleated target cells and to degrade their DNA. Furthermore, it exhibited 90 to 95% lower lytic activity to anti-CD3-coated SRBC. Conjugate formation with target cells, however, was normal. These data provide strong evidence that GA plays an important role in the cytolytic cycle, and that the quantity of enzyme is a limiting factor in these cytolytic cells.

  8. Unexpected transcellular protein crossover occurs during canonical DNA transfection.

    Science.gov (United States)

    Arsenault, Jason; Cuijpers, Sabine A G; Niranjan, Dhevahi; Davletov, Bazbek

    2014-12-01

    Transfection of DNA has been invaluable for biological sciences, yet the effects upon membrane homeostasis are far from negligible. Here, we demonstrate that Neuro2A cells transfected using Lipofectamine LTX with the fluorescently coupled Botulinum serotype A holoenzyme (EGFP-LcA) cDNA express this SNAP25 protease that can, once translated, escape the transfected host cytosol and become endocytosed into untransfected cells, without its innate binding and translocation domains. Fluorescent readouts revealed moderate transfection rates (30-50%) while immunoblotting revealed a surprisingly total enzymatic cleavage of SNAP25; the transgenic protein acted beyond the confines of its host cell. Using intracellular dyes, no important cytotoxic effects were observed from reagent treatment alone, which excluded the possibility of membrane ruptures, though noticeably, intracellular acidic organelles were redistributed towards the plasma membrane. This drastic, yet frequently unobserved, change in protein permeability and endosomal trafficking following reagent treatment highlights important concerns for all studies using transient transfection. © 2014 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.

  9. Characterization of nanoparticle mediated laser transfection by femtosecond laser pulses for applications in molecular medicine.

    Science.gov (United States)

    Schomaker, Markus; Heinemann, Dag; Kalies, Stefan; Willenbrock, Saskia; Wagner, Siegfried; Nolte, Ingo; Ripken, Tammo; Murua Escobar, Hugo; Meyer, Heiko; Heisterkamp, Alexander

    2015-02-03

    In molecular medicine, the manipulation of cells is prerequisite to evaluate genes as therapeutic targets or to transfect cells to develop cell therapeutic strategies. To achieve these purposes it is essential that given transfection techniques are capable of handling high cell numbers in reasonable time spans. To fulfill this demand, an alternative nanoparticle mediated laser transfection method is presented herein. The fs-laser excitation of cell-adhered gold nanoparticles evokes localized membrane permeabilization and enables an inflow of extracellular molecules into cells. The parameters for an efficient and gentle cell manipulation are evaluated in detail. Efficiencies of 90% with a cell viability of 93% were achieved for siRNA transfection. The proof for a molecular medical approach is demonstrated by highly efficient knock down of the oncogene HMGA2 in a rapidly proliferating prostate carcinoma in vitro model using siRNA. Additionally, investigations concerning the initial perforation mechanism are conducted. Next to theoretical simulations, the laser induced effects are experimentally investigated by spectrometric and microscopic analysis. The results indicate that near field effects are the initial mechanism of membrane permeabilization. This methodical approach combined with an automated setup, allows a high throughput targeting of several 100,000 cells within seconds, providing an excellent tool for in vitro applications in molecular medicine. NIR fs lasers are characterized by specific advantages when compared to lasers employing longer (ps/ns) pulses in the visible regime. The NIR fs pulses generate low thermal impact while allowing high penetration depths into tissue. Therefore fs lasers could be used for prospective in vivo applications.

  10. Advances in study of perpes simplex virus type 1-thymidine kinase reporter gene imaging

    International Nuclear Information System (INIS)

    Liu Ying; Lan Xiaoli; Zhang Yongxue

    2007-01-01

    Radionuclide reporter gene imaging is an effect way to provide qualitative and quantitative information for gene therapy. There are three systems of reporter gene including kinase reporter gene. perpes simplex virus type 1-thymidine kinase (HSV1-tk) has perfect physical and chemical characteristic which is suit for imaging as reporter gene. It has been widely investigated and intensively researched. Two substrates of HSV1-tk are purine nucleosite derivant and acyclovir derivant, which can also be used as reporter probes of HSV1-tk. (authors)

  11. Promoter, transgene, and cell line effects in the transfection of mammalian cells using PDMAEMA-based nano-stars

    Directory of Open Access Journals (Sweden)

    Alexander Raup

    2016-09-01

    Full Text Available Non-viral transfection protocols are typically optimized using standard cells and reporter proteins, potentially underestimating cellular or transgene effects. Here such effects were studied for two human (Jurkat, HEK-293 and two rodent (CHO-K1, L929 cell lines and three fluorescent reporter proteins. Expression of the enhanced green fluorescent protein (EGFP was studied under the control of the human elongation factor 1 alpha promoter and three viral promoters (SV40, SV40/enhancer, CMV, that of ZsYellow1 (yellow fluorescence and mCherry (red fluorescence for the CMV promoter. Results varied with the cell line, in particular for the Jurkat cells. Pair-wise co-transfection of the CMV controlled transgenes resulted in a significant fraction of monochromatic cells (EGFP for EGFP/YFP and EGFP/RFP co-transfections, YFP in case of YFP/RFP co-transfections. Only Jurkat cells were almost incapable of expressing YFP. Dilution of the plasmid DNA with a non-expressed plasmid showed cell line dependent effects on transfection efficiency and/or expression levels.

  12. PET/CT imaging of human somatostatin receptor 2 (hsstr2) as reporter gene for gene therapy

    International Nuclear Information System (INIS)

    Hofmann, M.; Gazdhar, A.; Weitzel, T.; Schmid, R.; Krause, T.

    2006-01-01

    Localized information on region-selective gene expression in small animals is widely obtained by use of reporter genes inducing light emission. Using these reporter genes for imaging deep inside the human body fluorescent probes are hindered by attenuation, scattering and possible fluorescence quenching. This can be overcome by use of radio-peptide receptors as reporter genes. Therefore, the feasibility of the somatostatin receptor 2 expression vector system for expression imaging was checked against a control vector containing luciferase gene. For in vivo transduction of vector DNA into the rat forelimb muscles the in vivo electroporation technique was chosen because of its high regio-selectivity. The gene expression was imaged by high-sensitive CCD camera (luciferase activity) and by PET/CT using a Ga-68-DOTATOC as radio peptide probe. The relative sstr2 expression was enhanced by gene transduction at maximum to a factor of 15. The PET/CT images could be fully quantified. The above demonstrated feasibility of radio-peptide PET/CT reporter gene imaging may serve in the future as a tool for full quantitative understanding of regional gene expression, especially in large animals and humans

  13. PET/CT imaging of human somatostatin receptor 2 (hsstr2) as reporter gene for gene therapy

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, M. [Molecular Imaging and Therapy Group (MIT-Bern), Clinic of Nuclear Medicine, Inselspital, Medical School Bern (Switzerland)]. E-mail: Michael.Hofmann@insel.ch; Gazdhar, A. [Division of Pulmonary Medicine, University Hospital Bern (Switzerland); Weitzel, T. [Molecular Imaging and Therapy Group (MIT-Bern), Clinic of Nuclear Medicine, Inselspital, Medical School Bern (Switzerland); Schmid, R. [Division of Thoracic Surgery, University Hospital Bern (Switzerland); Krause, T. [Molecular Imaging and Therapy Group (MIT-Bern), Clinic of Nuclear Medicine, Inselspital, Medical School Bern (Switzerland)

    2006-12-20

    Localized information on region-selective gene expression in small animals is widely obtained by use of reporter genes inducing light emission. Using these reporter genes for imaging deep inside the human body fluorescent probes are hindered by attenuation, scattering and possible fluorescence quenching. This can be overcome by use of radio-peptide receptors as reporter genes. Therefore, the feasibility of the somatostatin receptor 2 expression vector system for expression imaging was checked against a control vector containing luciferase gene. For in vivo transduction of vector DNA into the rat forelimb muscles the in vivo electroporation technique was chosen because of its high regio-selectivity. The gene expression was imaged by high-sensitive CCD camera (luciferase activity) and by PET/CT using a Ga-68-DOTATOC as radio peptide probe. The relative sstr2 expression was enhanced by gene transduction at maximum to a factor of 15. The PET/CT images could be fully quantified. The above demonstrated feasibility of radio-peptide PET/CT reporter gene imaging may serve in the future as a tool for full quantitative understanding of regional gene expression, especially in large animals and human000.

  14. Peptide-enhanced mRNA transfection in cultured mouse cardiac fibroblasts and direct reprogramming towards cardiomyocyte-like cells

    Directory of Open Access Journals (Sweden)

    Lee K

    2015-03-01

    Full Text Available Kunwoo Lee,1,2 Pengzhi Yu,3 Nithya Lingampalli,1 Hyun Jin Kim,1 Richard Tang,1 Niren Murthy1,2 1Department of Bioengineering, University of California, Berkeley, CA, USA; 2UC Berkeley and UCSF Joint Graduate Program in Bioengineering, Berkeley/San Francisco, CA, USA; 3Gladstone Institute of Cardiovascular Disease, San Francisco, CA, USA Abstract: The treatment of myocardial infarction is a major challenge in medicine due to the inability of heart tissue to regenerate. Direct reprogramming of endogenous cardiac fibroblasts into functional cardiomyocytes via the delivery of transcription factor mRNAs has the potential to regenerate cardiac tissue and to treat heart failure. Even though mRNA delivery to cardiac fibroblasts has the therapeutic potential, mRNA transfection in cardiac fibroblasts has been challenging. Herein, we develop an efficient mRNA transfection in cultured mouse cardiac fibroblasts via a polyarginine-fused heart-targeting peptide and lipofectamine complex, termed C-Lipo and demonstrate the partial direct reprogramming of cardiac fibroblasts towards cardiomyocyte cells. C-Lipo enabled the mRNA-induced direct cardiac reprogramming due to its efficient transfection with low toxicity, which allowed for multiple transfections of Gata4, Mef2c, and Tbx5 (GMT mRNAs for a period of 2 weeks. The induced cardiomyocyte-like cells had α-MHC promoter-driven GFP expression and striated cardiac muscle structure from a-actinin immunohistochemistry. GMT mRNA transfection of cultured mouse cardiac fibroblasts via C-Lipo significantly increased expression of the cardiomyocyte marker genes, Actc1, Actn2, Gja1, Hand2, and Tnnt2, after 2 weeks of transfection. Moreover, this study provides the first direct evidence that the stoichiometry of the GMT reprogramming factors influence the expression of cardiomyocyte marker genes. Our results demonstrate that mRNA delivery is a potential approach for cardiomyocyte generation. Keywords: direct cardiac

  15. Nonviral transfection of adipose tissue stromal cells: an experimental study.

    Science.gov (United States)

    Lopatina, T V; Kalinina, N I; Parfyonova, E V

    2009-04-01

    Delivery of plasmid DNA and interfering RNA into adipose tissue stromal cells was carried out by the methods of lipofection, calcium phosphate method, and by electroporation. The percent of transfected cells after delivery of plasmid DNA by the calcium phosphate method and lipofection was 0 and 15%, respectively, vs. more than 50% after electroporation. Similar results were obtained for delivery of short-strand RNA into cells. These data indicate that electroporation is the most effective method of nonviral transfection of adipose tissue stromal cells.

  16. A BAC-bacterial recombination method to generate physically linked multiple gene reporter DNA constructs

    Directory of Open Access Journals (Sweden)

    Gong Shiaochin

    2009-03-01

    Full Text Available Abstract Background Reporter gene mice are valuable animal models for biological research providing a gene expression readout that can contribute to cellular characterization within the context of a developmental process. With the advancement of bacterial recombination techniques to engineer reporter gene constructs from BAC genomic clones and the generation of optically distinguishable fluorescent protein reporter genes, there is an unprecedented capability to engineer more informative transgenic reporter mouse models relative to what has been traditionally available. Results We demonstrate here our first effort on the development of a three stage bacterial recombination strategy to physically link multiple genes together with their respective fluorescent protein (FP reporters in one DNA fragment. This strategy uses bacterial recombination techniques to: (1 subclone genes of interest into BAC linking vectors, (2 insert desired reporter genes into respective genes and (3 link different gene-reporters together. As proof of concept, we have generated a single DNA fragment containing the genes Trap, Dmp1, and Ibsp driving the expression of ECFP, mCherry, and Topaz FP reporter genes, respectively. Using this DNA construct, we have successfully generated transgenic reporter mice that retain two to three gene readouts. Conclusion The three stage methodology to link multiple genes with their respective fluorescent protein reporter works with reasonable efficiency. Moreover, gene linkage allows for their common chromosomal integration into a single locus. However, the testing of this multi-reporter DNA construct by transgenesis does suggest that the linkage of two different genes together, despite their large size, can still create a positional effect. We believe that gene choice, genomic DNA fragment size and the presence of endogenous insulator elements are critical variables.

  17. A BAC-bacterial recombination method to generate physically linked multiple gene reporter DNA constructs.

    Science.gov (United States)

    Maye, Peter; Stover, Mary Louise; Liu, Yaling; Rowe, David W; Gong, Shiaochin; Lichtler, Alexander C

    2009-03-13

    Reporter gene mice are valuable animal models for biological research providing a gene expression readout that can contribute to cellular characterization within the context of a developmental process. With the advancement of bacterial recombination techniques to engineer reporter gene constructs from BAC genomic clones and the generation of optically distinguishable fluorescent protein reporter genes, there is an unprecedented capability to engineer more informative transgenic reporter mouse models relative to what has been traditionally available. We demonstrate here our first effort on the development of a three stage bacterial recombination strategy to physically link multiple genes together with their respective fluorescent protein (FP) reporters in one DNA fragment. This strategy uses bacterial recombination techniques to: (1) subclone genes of interest into BAC linking vectors, (2) insert desired reporter genes into respective genes and (3) link different gene-reporters together. As proof of concept, we have generated a single DNA fragment containing the genes Trap, Dmp1, and Ibsp driving the expression of ECFP, mCherry, and Topaz FP reporter genes, respectively. Using this DNA construct, we have successfully generated transgenic reporter mice that retain two to three gene readouts. The three stage methodology to link multiple genes with their respective fluorescent protein reporter works with reasonable efficiency. Moreover, gene linkage allows for their common chromosomal integration into a single locus. However, the testing of this multi-reporter DNA construct by transgenesis does suggest that the linkage of two different genes together, despite their large size, can still create a positional effect. We believe that gene choice, genomic DNA fragment size and the presence of endogenous insulator elements are critical variables.

  18. Development of a cell-based reporter assay for screening of inhibitors of hypoxia-inducible factor 2-induced gene expression.

    Science.gov (United States)

    Woldemichael, Girma M; Vasselli, James R; Gardella, Roberta S; McKee, Tawnya C; Linehan, W Marston; McMahon, James B

    2006-09-01

    Reporter cell lines have been developed for the identification of inhibitors of gene expression enhanced by hypoxia-inducible factor 2, which has been implicated as a transcription factor involved in the tumorigenesis of clear cell renal carcinoma. Stably transformed reporter clones of the human renal clear cell carcinoma cell line 786-O were generated by transfection or retroviral infection. Luciferase reporter expression in the vectors used was driven by either the natural human vascular endothelial growth factor (VEGF) promoter-enhancer or by the VEGF and the human endothelial nitric oxide synthase enhancers modulating minimal human cytomegalovirus promoter. Utility of the generated reporter cell lines was validated by introducing the von Hippel-Lindau protein complex and testing for reporter inducibility by hypoxia. The dynamic range in reporter activity under hypoxic stress was found to be at least 30- to 40-fold, with a signal-to-noise ratio of 60:1. Properties of the cell lines such as tolerance to up to 3% DMSO, signal stability with multiple in vitro passages, and utility in both 96- and 384-well plate formats indicated their suitability for use in a high-throughput screen. In addition, the potential use of these reporter lines in the evaluation of high-throughput screening hits in vivo in various mice models has been demonstrated.

  19. Establishment, characterization, virus susceptibility and transfection of cell lines from cobia, Rachycentron canadum (L.), brain and fin.

    Science.gov (United States)

    Cheng, T-C; Lai, Y-S; Lin, I-Y; Wu, C-P; Chang, S-L; Chen, T-I; Su, M-S

    2010-02-01

    Establishment and characterization of two cobia, Rachycentron canadum, cell lines derived from cobia brain (CB) and cobia fin (CF) are described. Caudal fin and brain from juvenile cobia were dissociated for 30 and 10 min, respectively, in phosphate-buffered saline containing 0.25% trypsin at 25 degrees C. The optimal culture condition for both dissociated cells (primary cell culture) was at 28 degrees C in Leibovitz-15 medium containing 10% foetal bovine serum. The cells have been sub-cultured at a ratio of 1:2 for more than 160 passages over a period of 3 years. Origin of the cultured cells was verified by comparison of their sequences of mitochondrial cytochrome oxidase subunit I genes (cox I) with the cox 1 sequence from cobia muscle tissue. The cell lines showed polyploidy. No mycoplasma contamination was detected. Susceptibility to grouper iridovirus was observed for the CB cell line but not the CF cell line. Both cell lines expressed green fluorescent protein after being transfected with green fluorescent reporter gene driven by the cytomegalovirus promoter.

  20. Comparative study of cellular kinetics of reporter probe [{sup 131}I]FIAU in neonatal cardiac myocytes after transfer of HSV1-tk reporter gene with two vectors

    Energy Technology Data Exchange (ETDEWEB)

    Lan Xiaoli [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Hubei Province Key Laboratory of Molecular Imaging, Wuhan 430022 (China)], E-mail: lxl730724@hotmail.com; Yin Xiaohua; Wang Ruihua; Liu Ying [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China); Hubei Province Key Laboratory of Molecular Imaging, Wuhan 430022 (China); Zhang Yongxue [Department of Nuclear Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022 (China) and Hubei Province Key Laboratory of Molecular Imaging, Wuhan 430022 (China)], E-mail: zhyx1229@163.com

    2009-02-15

    Aim: Reporter gene imaging is a promising approach for noninvasive monitoring of cardiac gene therapy. In this study, HSV1-tk (herpes simplex virus type 1 thymidine kinase) and FIAU (2'-fluoro-2'-deoxy-1-{beta}-D-arabinofuranosyl-5-iodouracil) were used as the reporter gene and probe, respectively. Cellular uptakes of radiolabeled FIAU of neonatal rat cardiac myocytes transferred with HSV1-tk were compared between two vectors, adenovirus and liposome. The aims of this study were to choose the better vector and to provide a theoretical basis for good nuclide images. Methods: Neonatal cardiac myocytes were obtained from rat heart by single collagenase digestion. HSV1-tk inserted into adenovirus vector (recombinant adenovirus type 5, Ad5-tk) and plasmid (pDC316-tk) coated with Lipofectamine 2000 (pDC316-tk/lipoplex) were developed; thus, HSV1-tk could be transferred into neonatal cardiac myocytes. FAU (2'-fluoro-2'-deoxy-1-{beta}-D-arabinofuranosyluracil) was labeled with {sup 131}I, and the product was assessed after purification with reversed-phase Sep-Pak C-18 column. The uptake rates of [{sup 131}I]FIAU in the transferred cardiac myocytes at different times (0.5, 1, 2, 3, 4 and 5 h) were detected. Furthermore, mRNA expression and protein expression of HSV1-tk were detected by semiquantitative reverse-transcriptase polymerase chain reaction and immunocytochemistry. Results: FAU could be labeled with {sup 131}I, and the labeling efficiency and radiochemical purity rates were 53.82{+-}2.05% and 94.85{+-}1.76%, respectively. Time-dependent increase of the accumulation of [{sup 131}I]FIAU was observed in both the Ad5-tk group and the pDC316/lipoplex group, and the highest uptake rate occurred at 5 h, with peak values of 12.55{+-}0.37% and 2.09{+-}0.34%, respectively. Greater uptakes of [{sup 131}I]FIAU in Ad5-tk-infected cells compared with pDC316/lipoplex-transfected ones occurred at all the time points (t=12.978-38.253, P<.01). The exogenous gene

  1. In Vitro and In Vivo Characterization of a Dual-Function Green Fluorescent Protein–HSV1-Thymidine Kinase Reporter Gene Driven by the Human Elongation Factor 1α Promoter

    Directory of Open Access Journals (Sweden)

    Gary D. Luker

    2002-04-01

    Full Text Available Toward the goal of monitoring activity of native mammalian promoters with molecular imaging techniques, we stably transfected DU145 prostate carcinoma cells with a fusion construct of enhanced green fluorescent protein (EGFP and wild-type herpes simplex virus-1 thymidine kinase (HSV1-TK as a reporter gene driven by the promoter for human elongation factor 1α (EF-1α-EGFP-TK. Using this model system, expression of EGFP was quantified by flow cytometry and fluorescence microscopy, while the HSV1-TK component of the reporter was quantified with 8-[3H]ganciclovir (8-[3H]GCV. As analyzed by flow cytometry, passage of EGFP-TK-DU145 transfected cells (ETK in vitro resulted in populations of cells with high and low expression of EGFP over time. High and low ETK cells retained 23-fold and 5-fold more GCV, respectively, than control. While differences in uptake and retention of GCV corresponded to relative expression of the reporter gene in each subpopulation of cells as determined by both flow cytometry (EGFP and quantitative RT-PCR, the correlation was not linear. Furthermore, in high ETK cells, net retention of various radiolabeled nucleoside analogues varied; the rank order was 8-[3H]GCV < 9-(4-fluoro-3-hydroxymethylbutylguanine ([18F]FHBG ≈ 8-[3H]penciclovir (8-[3H]PCV < 2′-fluoro-2′-deoxy-5-iodouracil-beta-d-arabinofuranoside (2-[14C]FIAU. Xenograft tumors of ETK cells in vivo accumulated 2.5-fold more 8-[3H]GCV per gram of tissue and showed greater fluorescence from EGFP than control DU145 cells, demonstrating that the reporter gene functioned in vivo. These data extend previous reports by showing that a human promoter can be detected in vitro and in vivo with a dual-function reporter exploiting optical and radiotracer techniques.

  2. Optimization of in vitro culture and transfection condition of bovine ...

    African Journals Online (AJOL)

    The present study aimed to optimize the in vitro culture and transfection efficiency of bovine primary spermatogonial stem cells (SSCs). To this end, SSCs were obtained from newborn Holstein bull calves by two-step enzymatic digestion. After enrichment and culture, SSCs were characterized by using alkaline phosphatase ...

  3. Establishing malaria parasite transfection technology in South Africa

    CSIR Research Space (South Africa)

    Van Brummelen, AC

    2010-01-01

    Full Text Available -richness and intracellular location of the organism. As a result such successful transfection often requires prolonged periods (up to 2-3 months) of constant and patient culturing and selection. In addition, plasmids usually have a complicated composition and require lengthy...

  4. Photo-transfection of mammalian cells via femtosecond laser pulses

    CSIR Research Space (South Africa)

    Mthunzi, P

    2009-06-01

    Full Text Available on transient photo-transfection of ovary (CHO-Kl), neuroblastoma (NG-I08 & SKN-SH) and embryonic kidney (HEK-293) as well as primary non-differentiated stem cells (EI4g2a) using a tightly focused titanium sapphire laser beam (1.1 urn diameter spot size...

  5. Transfected Babesia bovis Expressing a Tick GST as a Live Vector Vaccine

    Science.gov (United States)

    Oldiges, Daiane P.; Laughery, Jacob M.; Tagliari, Nelson Junior; Leite Filho, Ronaldo Viana; Davis, William C.; da Silva Vaz, Itabajara; Termignoni, Carlos; Knowles, Donald P.; Suarez, Carlos E.

    2016-01-01

    The Rhipicephalus microplus tick is a notorious blood-feeding ectoparasite of livestock, especially cattle, responsible for massive losses in animal production. It is the main vector for transmission of pathogenic bacteria and parasites, including Babesia bovis, an intraerythrocytic apicomplexan protozoan parasite responsible for bovine Babesiosis. This study describes the development and testing of a live B. bovis vaccine expressing the protective tick antigen glutathione-S-transferase from Haemaphysalis longicornis (HlGST). The B. bovis S74-T3B parasites were electroporated with a plasmid containing the bidirectional Ef-1α (elongation factor 1 alpha) promoter of B. bovis controlling expression of two independent genes, the selectable marker GFP-BSD (green fluorescent protein–blasticidin deaminase), and HlGST fused to the MSA-1 (merozoite surface antigen 1) signal peptide from B. bovis. Electroporation followed by blasticidin selection resulted in the emergence of a mixed B. bovis transfected line (termed HlGST) in in vitro cultures, containing parasites with distinct patterns of insertion of both exogenous genes, either in or outside the Ef-1α locus. A B. bovis clonal line termed HlGST-Cln expressing intracellular GFP and HlGST in the surface of merozoites was then derived from the mixed parasite line HlGST using a fluorescent activated cell sorter. Two independent calf immunization trials were performed via intravenous inoculation of the HlGST-Cln and a previously described control consisting of an irrelevant transfected clonal line of B. bovis designated GFP-Cln. The control GFP-Cln line contains a copy of the GFP-BSD gene inserted into the Ef-1α locus of B. bovis in an identical fashion as the HIGST-Cln parasites. All animals inoculated with the HlGST-Cln and GFP-Cln transfected parasites developed mild babesiosis. Tick egg fertility and fully engorged female tick weight was reduced significantly in R. microplus feeding on HlGST-Cln-immunized calves

  6. Transfected Babesia bovis Expressing a Tick GST as a Live Vector Vaccine.

    Directory of Open Access Journals (Sweden)

    Daiane P Oldiges

    2016-12-01

    Full Text Available The Rhipicephalus microplus tick is a notorious blood-feeding ectoparasite of livestock, especially cattle, responsible for massive losses in animal production. It is the main vector for transmission of pathogenic bacteria and parasites, including Babesia bovis, an intraerythrocytic apicomplexan protozoan parasite responsible for bovine Babesiosis. This study describes the development and testing of a live B. bovis vaccine expressing the protective tick antigen glutathione-S-transferase from Haemaphysalis longicornis (HlGST. The B. bovis S74-T3B parasites were electroporated with a plasmid containing the bidirectional Ef-1α (elongation factor 1 alpha promoter of B. bovis controlling expression of two independent genes, the selectable marker GFP-BSD (green fluorescent protein-blasticidin deaminase, and HlGST fused to the MSA-1 (merozoite surface antigen 1 signal peptide from B. bovis. Electroporation followed by blasticidin selection resulted in the emergence of a mixed B. bovis transfected line (termed HlGST in in vitro cultures, containing parasites with distinct patterns of insertion of both exogenous genes, either in or outside the Ef-1α locus. A B. bovis clonal line termed HlGST-Cln expressing intracellular GFP and HlGST in the surface of merozoites was then derived from the mixed parasite line HlGST using a fluorescent activated cell sorter. Two independent calf immunization trials were performed via intravenous inoculation of the HlGST-Cln and a previously described control consisting of an irrelevant transfected clonal line of B. bovis designated GFP-Cln. The control GFP-Cln line contains a copy of the GFP-BSD gene inserted into the Ef-1α locus of B. bovis in an identical fashion as the HIGST-Cln parasites. All animals inoculated with the HlGST-Cln and GFP-Cln transfected parasites developed mild babesiosis. Tick egg fertility and fully engorged female tick weight was reduced significantly in R. microplus feeding on Hl

  7. Intracellular ROS mediates gas plasma-facilitated cellular transfection in 2D and 3D cultures

    Science.gov (United States)

    Xu, Dehui; Wang, Biqing; Xu, Yujing; Chen, Zeyu; Cui, Qinjie; Yang, Yanjie; Chen, Hailan; Kong, Michael G.

    2016-01-01

    This study reports the potential of cold atmospheric plasma (CAP) as a versatile tool for delivering oligonucleotides into mammalian cells. Compared to lipofection and electroporation methods, plasma transfection showed a better uptake efficiency and less cell death in the transfection of oligonucleotides. We demonstrated that the level of extracellular aqueous reactive oxygen species (ROS) produced by gas plasma is correlated with the uptake efficiency and that this is achieved through an increase of intracellular ROS levels and the resulting increase in cell membrane permeability. This finding was supported by the use of ROS scavengers, which reduced CAP-based uptake efficiency. In addition, we found that cold atmospheric plasma could transfer oligonucleotides such as siRNA and miRNA into cells even in 3D cultures, thus suggesting the potential for unique applications of CAP beyond those provided by standard transfection techniques. Together, our results suggest that cold plasma might provide an efficient technique for the delivery of siRNA and miRNA in 2D and 3D culture models. PMID:27296089

  8. Induction of osteogenic differentiation of stem cells via a lyophilized microRNA reverse transfection formulation on a tissue culture plate

    Directory of Open Access Journals (Sweden)

    Wu K

    2013-05-01

    Full Text Available Kaimin Wu,1,* Jie Xu,2,* Mengyuan Liu,1 Wen Song,1 Jun Yan,1 Shan Gao,3 Lingzhou Zhao,2 Yumei Zhang1 1Department of Prosthetic Dentistry, 2Department of Periodontology and Oral Medicine, School of Stomatology, The Fourth Military Medical University, Xi’an, People’s Republic of China; 3The Interdisciplinary Nanoscience Center and Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark; School of Stomatology, Tianjin Medical University, Tianjin, People’s Republic of China*Both authors contributed equally to this workAbstract: MicroRNA (miRNA regulation is a novel approach to manipulating the fate of mesenchymal stem cells, but an easy, safe, and highly efficient method of transfection is required. In this study, we developed an miRNA reverse transfection formulation by lyophilizing Lipofectamine 2000-miRNA lipoplexes on a tissue culture plate. The lipoplexes can be immobilized on a tissue culture plate with an intact pseudospherical structure and lyophilization without any lyoprotectant. In this study, reverse transfection resulted in highly efficient cellular uptake of miRNA and enabled significant manipulation of the intracellular target miRNA level. Reverse transfection formulations containing Lipofectamine 2000 1 µL per well generated much higher transfection efficiency without obvious cytotoxicity compared with conventional and other transfection methods. Further, the transfection efficiency of the reverse transfection formulations did not deteriorate during 90 days of storage at 4°C and -20°C. We then assessed the efficiency of the miRNA reverse transfection formulation in promoting osteogenic differentiation of mesenchymal stem cells. We found that transfection with anti-miR-138 and miR-148b was efficient for enhancing osteogenic differentiation, as indicated by enhanced osteogenesis-related gene expression, amount of alkaline phosphatase present, production of collagen, and matrix mineralization. Overall

  9. Enhanced photo-transfection efficiency of mammalian cells on graphene coated substrates

    Science.gov (United States)

    Mthunzi, Patience; He, Kuang; Ngcobo, Sandile; Warner, Jamie W.

    2014-03-01

    Literature reports graphene, an atomic-thick sheet of carbon atoms as one of the promising biocompatible scaffolds that promotes cellular proliferation in human mesenchymal stem cells. On the other hand, different mammalian cell lines including the induced pluripotent stem cells exhibited an accelerated proliferation rate when cultured on graphene or graphene oxide coated substrates. These findings provide strong motivation to explore the full capability of graphene in further pluripotent stem cell research activities as there exists an urgent requirement to preserve their therapeutic potential. This therefore calls for non-invasive procedures for handling stem cells in-vitro. For example, resent literature has shown successful laser light driven transfection in both multipotent and pluripotent stem cells. In order to explore the non-invasive nature of optical transfection alongside biocompatible qualities of graphene, in this work we investigated the impact of optically transfecting mouse embryonic stem (mES) cells plated on graphene coated sample chambers. Using Chinese Hamster Ovary cells (CHO-K1), we further studied the influence of graphene on cell viability as well as cell cytotoxicity through assessing changes in levels of mitochondrial adenosine triphosphate (ATP) activity and the release of cytosolic lactate dehydrogenase (LHD) respectively. Our results showed that compared to those treated on plain glass, CHO-K1 cells optically treated while plated on graphene coated substrates exhibited a higher production of ATP and a milder release of LDH. In addition there was enhanced photo-transfection efficiency in both CHO-K1 and mES cells irradiated on graphene sample chambers.

  10. Development of porcine transgenic nuclear-transferred embryos derived from fibroblast cells transfected by the novel technique of nucleofection or standard lipofection.

    Science.gov (United States)

    Skrzyszowska, M; Samiec, M; Słomski, R; Lipiński, D; Mały, E

    2008-07-15

    The aim of our study was to determine the in vitro developmental potential of porcine nuclear-transferred (NT) embryos that had been reconstructed with Tg(pWAPhGH-GFPBsd) transgene-expressing fibroblast cells. The gene construct was introduced into fibroblast cells by the novel method of nucleofection or standard lipofection. NT oocytes derived from foetal and adult dermal fibroblast cells were stimulated by either simultaneous fusion and electrical activation (Groups IA and IB) or sequential electrical and chemical activation (Groups IIA and IIB). The percentages of cloned embryos that reached the morula and blastocyst stages were 152/254 (59.8%) and 77/254 (30.3%) or 139/276 (50.4%) and 45/276 (16.3%) in Groups IA or IB, respectively. The rates of NT embryos that developed to the morula and blastocyst stages were 103/179 (57.5%) and 41/179 (22.9%) or 84/193 (43.5%) and 27/193 (14.0%) in Groups IIA and IIB, respectively. In conclusion, the in vitro developmental competences of porcine transgenic NT embryos that had been reconstructed with the Tg(pWAPhGH-GFPBsd) gene-transfected fibroblast cells were relatively high. Further, the nucleofection efficiency of all the porcine fibroblast cell lines as estimated by intra-vitam fluorescent evaluation based on the index of reporter eGFP transgene expression was nearly 100%. However, PCR analysis for transgene screening confirmed the absence of Tg(pWAPhGH-GFPBsd) fusion gene in some of the nucleofected cell lines. To our knowledge, the novel method of nucleofection is the first to transfect nuclear donor cells in the production of transgenic cloned embryos.

  11. Using the 2A Protein Coexpression System: Multicistronic 2A Vectors Expressing Gene(s) of Interest and Reporter Proteins.

    Science.gov (United States)

    Luke, Garry A; Ryan, Martin D

    2018-01-01

    To date, a huge range of different proteins-many with cotranslational and posttranslational subcellular localization signals-have been coexpressed together with various reporter proteins in vitro and in vivo using 2A peptides. The pros and cons of 2A co-expression technology are considered below, followed by a simple example of a "how to" protocol to concatenate multiple genes of interest, together with a reporter gene, into a single gene linked via 2As for easy identification or selection of transduced cells.

  12. 99Tcm pertechnetate uptake by hepatoma cells induced by tissue specific hNIS gene expression

    International Nuclear Information System (INIS)

    Chen Libo; Luo Quanyong; Yu Yongli; Yuan Zhibin; Lu Hankui; Zhu Ruisen; Guo Lihe

    2007-01-01

    Objective: Human sodium/iodide symporter (hNIS) gene could be used both as an ideal reporter gene and promising therapeutic gene. Rather than radioiodine, 99 Tc m pertechnetate has been proven to be a better radiopharmaceutical for tracing and imaging purposes. Herein, the authors investigated the feasibility of monitoring hNIS gene expression in hepatoma cells using 99 Tc m pertechnetate as a tracer. Methods: Hepatoma cells MH3924A were stably transfected with recombinant retroviral vector in which hNIS cDNA was driven by murine albumin enhancer/promoter (mAlb) and coupled to hygromycin resistance gene. The uptake and efflux of 99 Tc m pertechnetate by transfected hepatoma cells were tested with 99 Tc m pertechnetate (74 kBq) solution adulterated into the culture media and counted after media suspension discharge at different intervals. In further tests, 50 μmol/L NaClO 4 and 500 μmol/L Ouabain were added into the media for 99 Tc m inhibition tests. For in vive studies, five ACI rats bearing NIS transfected hepatoma xenografts were injected with 99 Tc m pertechnetate (15.8 MBq) and followed by dynamic acquisition (0.57 1, 2 and 4 h) with small gamma camera to semi-quantitatively analyze the radioactivity distribution. Results: In vitro tests, the peak uptake of 99 Tc m pertechnetate by cultured transfected MH3924A cells was up to 254 folds higher than that by the wild type cells. 99 Tc m uptake by transfected cells were significantly inhibited by NaClO 4 down to 2.44% (P 99 Tc m pertechnetate out of cultured transfected cells became rapid immediately after renewal of culture media (half life 99 Tc m accumulations by hNIS transfected tumor xenografts were obvious in early phases of the acquisition with peak uptake at 12 min and gradually declining later on. Conclusions: hNIS transfected hepatoma cells can avidly uptake 99 Tc m pertechnetate both in vitro and in vive. It is feasible to utilize 99 Tc m pertechnetate for monitoring and even quantitatively analyzing

  13. A luciferase reporter gene assay and aryl hydrocarbon receptor 1 genotype predict the LD50 of polychlorinated biphenyls in avian species

    International Nuclear Information System (INIS)

    Manning, Gillian E.; Farmahin, Reza; Crump, Doug; Jones, Stephanie P.; Klein, Jeff; Konstantinov, Alex; Potter, Dave; Kennedy, Sean W.

    2012-01-01

    Birds differ in sensitivity to the embryotoxic effects of polychlorinated biphenyls (PCBs), which complicates environmental risk assessments for these chemicals. Recent research has shown that the identities of amino acid residues 324 and 380 in the avian aryl hydrocarbon receptor 1 (AHR1) ligand binding domain (LBD) are primarily responsible for differences in avian species sensitivity to selected dibenzo-p-dioxins and furans. A luciferase reporter gene (LRG) assay was developed in our laboratory to measure AHR1-mediated induction of a cytochrome P450 1A5 reporter gene in COS-7 cells transfected with different avian AHR1 constructs. In the present study, the LRG assay was used to measure the concentration-dependent effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and PCBs 126, 77, 105 and 118 on luciferase activity in COS-7 cells transfected with AHR1 constructs representative of 86 avian species in order to predict their sensitivity to PCB-induced embryolethality and the relative potency of PCBs in these species. The results of the LRG assay indicate that the identity of amino acid residues 324 and 380 in the AHR1 LBD are the major determinants of avian species sensitivity to PCBs. The relative potency of PCBs did not differ greatly among AHR1 constructs. Luciferase activity was significantly correlated with embryolethality data obtained from the literature (R 2 ≥ 0.87, p < 0.0001). Thus, the LRG assay in combination with the knowledge of a species' AHR1 LBD sequence can be used to predict PCB-induced embryolethality in potentially any avian species of interest without the use of lethal methods on a large number of individuals. -- Highlights: ► PCB embryolethality in birds can be predicted from a species' AHR1 genotype. ► The reporter gene assay is useful for predicting species sensitivity to PCBs. ► The relative potency of PCBs does not appear to differ between AHR1 genotypes. ► Contamination of PCB 105 and PCB 118 did not affect their relative

  14. A luciferase reporter gene assay and aryl hydrocarbon receptor 1 genotype predict the LD{sub 50} of polychlorinated biphenyls in avian species

    Energy Technology Data Exchange (ETDEWEB)

    Manning, Gillian E., E-mail: gmann017@uottawa.ca [Centre for Advanced Research in Environmental Genomics, Department of Biology, University of Ottawa, Ottawa, ON, Canada K1N 6N5 (Canada); Environment Canada, National Wildlife Research Centre, Ottawa, ON, Canada K1A 0H3 (Canada); Farmahin, Reza, E-mail: mfarm070@uottawa.ca [Centre for Advanced Research in Environmental Genomics, Department of Biology, University of Ottawa, Ottawa, ON, Canada K1N 6N5 (Canada); Environment Canada, National Wildlife Research Centre, Ottawa, ON, Canada K1A 0H3 (Canada); Crump, Doug, E-mail: doug.crump@ec.gc.ca [Environment Canada, National Wildlife Research Centre, Ottawa, ON, Canada K1A 0H3 (Canada); Jones, Stephanie P., E-mail: stephanie.jones@ec.gc.ca [Environment Canada, National Wildlife Research Centre, Ottawa, ON, Canada K1A 0H3 (Canada); Klein, Jeff, E-mail: jeffery@well-labs.com [Wellington Laboratories Inc., Research Division, Guelph, ON, Canada N1G 3M5 (Canada); Konstantinov, Alex, E-mail: alex@well-labs.com [Wellington Laboratories Inc., Research Division, Guelph, ON, Canada N1G 3M5 (Canada); Potter, Dave, E-mail: dpotter@well-labs.com [Wellington Laboratories Inc., Research Division, Guelph, ON, Canada N1G 3M5 (Canada); Kennedy, Sean W., E-mail: sean.kennedy@ec.gc.ca [Centre for Advanced Research in Environmental Genomics, Department of Biology, University of Ottawa, Ottawa, ON, Canada K1N 6N5 (Canada); Environment Canada, National Wildlife Research Centre, Ottawa, ON, Canada K1A 0H3 (Canada)

    2012-09-15

    Birds differ in sensitivity to the embryotoxic effects of polychlorinated biphenyls (PCBs), which complicates environmental risk assessments for these chemicals. Recent research has shown that the identities of amino acid residues 324 and 380 in the avian aryl hydrocarbon receptor 1 (AHR1) ligand binding domain (LBD) are primarily responsible for differences in avian species sensitivity to selected dibenzo-p-dioxins and furans. A luciferase reporter gene (LRG) assay was developed in our laboratory to measure AHR1-mediated induction of a cytochrome P450 1A5 reporter gene in COS-7 cells transfected with different avian AHR1 constructs. In the present study, the LRG assay was used to measure the concentration-dependent effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and PCBs 126, 77, 105 and 118 on luciferase activity in COS-7 cells transfected with AHR1 constructs representative of 86 avian species in order to predict their sensitivity to PCB-induced embryolethality and the relative potency of PCBs in these species. The results of the LRG assay indicate that the identity of amino acid residues 324 and 380 in the AHR1 LBD are the major determinants of avian species sensitivity to PCBs. The relative potency of PCBs did not differ greatly among AHR1 constructs. Luciferase activity was significantly correlated with embryolethality data obtained from the literature (R{sup 2} ≥ 0.87, p < 0.0001). Thus, the LRG assay in combination with the knowledge of a species' AHR1 LBD sequence can be used to predict PCB-induced embryolethality in potentially any avian species of interest without the use of lethal methods on a large number of individuals. -- Highlights: ► PCB embryolethality in birds can be predicted from a species' AHR1 genotype. ► The reporter gene assay is useful for predicting species sensitivity to PCBs. ► The relative potency of PCBs does not appear to differ between AHR1 genotypes. ► Contamination of PCB 105 and PCB 118 did not affect

  15. Mutant p53 transfection of astrocytic cells results in altered cell cycle control, radiation sensitivity, and tumorigenicity

    International Nuclear Information System (INIS)

    Kanady, Kirk E.; Mei Su; Proulx, Gary; Malkin, David M.; Pardo, Francisco S.

    1995-01-01

    Introduction: Alterations in the p53 tumor suppressor gene are one of the most frequent genetic alterations in malignant gliomas. An understanding of the molecular genetic events leading to glial tumor progression would aid in designing therapeutic vectors for controlling these challenging tumor types. We investigated whether mutations in coding exons of the p53 gene result in functional changes altering cell cycle 'checkpoint' control and the intrinsic radiation sensitivity of glial cells. Methods: An astrocytic cell line was derived from a low grade astrocytoma and characterized to be of human karyotype and GFAP positivity. Additionally, the cellular population has never formed tumors in immune-deficient mice. At early passage ( 2 as parameters. Cell kinetic analyses after 2, 5, and 10 Gy of ionizing radiation were conducted using propidium iodide FACS analyses. Results: Overall levels of p53 expression were increased 5-10 fold in the transfected cellular populations. Astrocytic cellular populations transfected with mutant p53 revealed a statistically significant increase in levels of resistance to ionizing radiation in vitro (2-tailed test, SF2, MID). Astrocytic cellular populations transfected with mutant p53, unlike the parental cells, were tumorigenic in SCID mice. Cell kinetic analyses indicated that the untransfected cell line demonstrated dose dependent G1 and G2 arrests. Following transfection, however, the resultant cellular population demonstrated a predominant G2 arrest. Conclusions: Astrocytic cellular populations derived from low grade astrocytomas, are relatively radiation sensitive, non-tumorigenic, and have intact cell cycle ''checkpoints.'' Cellular populations resulting upon transfection of parental cells with a dominant negative p53 mutation, are relatively radiation resistant, when compared to both parental and mock-transfected cells. Transfected cells demonstrate abnormalities of cell cycle control at the G1/S checkpoint, increases in levels

  16. Simulation of micro/nano electroporation for cell transfection

    Science.gov (United States)

    Zhang, Guocheng; Fan, Na; Jiang, Hai; Guo, Jian; Peng, Bei

    2018-03-01

    The 3D micro/nano electroporation for transfection has become a powerful biological cell research technique with the development of micro-nano manufacturing technology. The micro channels connected the cells with transfection reagents on the chip were important to the transmemnbrane potentical, which directly influences the electroporation efficiency. In this study, a two-dimensional model for electroporation of cells was designed to address the effects of channels’ sizes and number on transmembrane potential. The simulation results indicated that the transmembrane potential increased with increasing size of channels’ entrances. Moreover, compared with single channel entrance, the transmembrane potential was higher when the cells located at multiple channels entrances. These results suggest that it IS required to develop higher micro manufacturing technology to create channels as we expected size.

  17. Molecular MR imaging of cancer gene therapy. Ferritin transgene reporter takes the stage

    International Nuclear Information System (INIS)

    Hasegawa, Sumitaka; Furukawa, Takako; Saga, Tsuneo

    2010-01-01

    Molecular imaging using magnetic resonance (MR) imaging has been actively investigated and made rapid progress in the past decade. Applied to cancer gene therapy, the technique's high spatial resolution allows evaluation of gene delivery into target tissues. Because noninvasive monitoring of the duration, location, and magnitude of transgene expression in tumor tissues or cells provides useful information for assessing therapeutic efficacy and optimizing protocols, molecular imaging is expected to become a critical step in the success of cancer gene therapy in the near future. We present a brief overview of the current status of molecular MR imaging, especially in vivo reporter gene imaging using ferritin and other reporters, discuss its application to cancer gene therapy, and present our research of MR imaging detection of electroporation-mediated cancer gene therapy using the ferritin reporter gene. (author)

  18. A comparison of synthetic oligodeoxynucleotides, DNA fragments and AAV-1 for targeted episomal and chromosomal gene repair

    Directory of Open Access Journals (Sweden)

    Leclerc Xavier

    2009-04-01

    Full Text Available Abstract Background Current strategies for gene therapy of inherited diseases consist in adding functional copies of the gene that is defective. An attractive alternative to these approaches would be to correct the endogenous mutated gene in the affected individual. This study presents a quantitative comparison of the repair efficiency using different forms of donor nucleic acids, including synthetic DNA oligonucleotides, double stranded DNA fragments with sizes ranging from 200 to 2200 bp and sequences carried by a recombinant adeno-associated virus (rAAV-1. Evaluation of each gene repair strategy was carried out using two different reporter systems, a mutated eGFP gene or a dual construct with a functional eGFP and an inactive luciferase gene, in several different cell systems. Gene targeting events were scored either following transient co-transfection of reporter plasmids and donor DNAs, or in a system where a reporter construct was stably integrated into the chromosome. Results In both episomal and chromosomal assays, DNA fragments were more efficient at gene repair than oligonucleotides or rAAV-1. Furthermore, the gene targeting frequency could be significantly increased by using DNA repair stimulating drugs such as doxorubicin and phleomycin. Conclusion Our results show that it is possible to obtain repair frequencies of 1% of the transfected cell population under optimized transfection protocols when cells were pretreated with phleomycin using rAAV-1 and dsDNA fragments.

  19. Stem Cell Gene Therapy for Fanconi Anemia: Report from the 1st International Fanconi Anemia Gene Therapy Working Group Meeting

    Science.gov (United States)

    Tolar, Jakub; Adair, Jennifer E; Antoniou, Michael; Bartholomae, Cynthia C; Becker, Pamela S; Blazar, Bruce R; Bueren, Juan; Carroll, Thomas; Cavazzana-Calvo, Marina; Clapp, D Wade; Dalgleish, Robert; Galy, Anne; Gaspar, H Bobby; Hanenberg, Helmut; Von Kalle, Christof; Kiem, Hans-Peter; Lindeman, Dirk; Naldini, Luigi; Navarro, Susana; Renella, Raffaele; Rio, Paula; Sevilla, Julián; Schmidt, Manfred; Verhoeyen, Els; Wagner, John E; Williams, David A; Thrasher, Adrian J

    2011-01-01

    Survival rates after allogeneic hematopoietic cell transplantation (HCT) for Fanconi anemia (FA) have increased dramatically since 2000. However, the use of autologous stem cell gene therapy, whereby the patient's own blood stem cells are modified to express the wild-type gene product, could potentially avoid the early and late complications of allogeneic HCT. Over the last decades, gene therapy has experienced a high degree of optimism interrupted by periods of diminished expectation. Optimism stems from recent examples of successful gene correction in several congenital immunodeficiencies, whereas diminished expectations come from the realization that gene therapy will not be free of side effects. The goal of the 1st International Fanconi Anemia Gene Therapy Working Group Meeting was to determine the optimal strategy for moving stem cell gene therapy into clinical trials for individuals with FA. To this end, key investigators examined vector design, transduction method, criteria for large-scale clinical-grade vector manufacture, hematopoietic cell preparation, and eligibility criteria for FA patients most likely to benefit. The report summarizes the roadmap for the development of gene therapy for FA. PMID:21540837

  20. Development and Validation of a Novel Dual Luciferase Reporter Gene Assay to Quantify Ebola Virus VP24 Inhibition of IFN Signaling

    Directory of Open Access Journals (Sweden)

    Elisa Fanunza

    2018-02-01

    Full Text Available The interferon (IFN system is the first line of defense against viral infections. Evasion of IFN signaling by Ebola viral protein 24 (VP24 is a critical event in the pathogenesis of the infection and, hence, VP24 is a potential target for drug development. Since no drugs target VP24, the identification of molecules able to inhibit VP24, restoring and possibly enhancing the IFN response, is a goal of concern. Accordingly, we developed a dual signal firefly and Renilla luciferase cell-based drug screening assay able to quantify IFN-mediated induction of Interferon Stimulated Genes (ISGs and its inhibition by VP24. Human Embryonic Kidney 293T (HEK293T cells were transiently transfected with a luciferase reporter gene construct driven by the promoter of ISGs, Interferon-Stimulated Response Element (ISRE. Stimulation of cells with IFN-α activated the IFN cascade leading to the expression of ISRE. Cotransfection of cells with a plasmid expressing VP24 cloned from a virus isolated during the last 2014 outbreak led to the inhibition of ISRE transcription, quantified by a luminescent signal. To adapt this system to test a large number of compounds, we performed it in 96-well plates; optimized the assay analyzing different parameters; and validated the system by calculating the Z′- and Z-factor, which showed values of 0.62 and 0.53 for IFN-α stimulation assay and VP24 inhibition assay, respectively, indicative of robust assay performance.

  1. Ultraviolet light-resistant primary transfectants of xeroderma pigmentosum cells are also DNA repair-proficient

    International Nuclear Information System (INIS)

    Stark, M.; Naiman, T.; Canaani, D.

    1989-01-01

    In a previous work, an immortal xeroderma pigmentosum cell line belonging to complementation group C was complemented to a UV-resistant phenotype by transfection with a human cDNA clone library. We now report that the primary transformants selected for UV-resistance also acquired normal levels of DNA repair. This was assessed both by measurement of UV-induced [ 3 H]thymidine incorporation and by equilibrium sedimentation analysis of repair-DNA synthesis. Therefore, the transduced DNA element which confers normal UV-resistance also corrects the excision repair defect of the xeroderma pigmentosum group C cell line

  2. Two skin cell lines from wild-type and albino Japanese flounder (Paralichthys olivaceus): establishment, characterization, virus susceptibility, efficient transfection, and application to albinism study.

    Science.gov (United States)

    Wang, Ruoqing; Zhang, Nianwei; Wang, Renkai; Wang, Shengpeng; Wang, Na

    2017-12-01

    In order to provide an applicable cell platform to study fish pathology and skin pigmentation, two cell lines derived from skin tissues of wild-type and albino Japanese flounder were established and named JFSK_wt and JFSK_alb, respectively. These two cell lines were cultured for 45 passages within approximately 300 days. JFSK_wt and JFSK_alb cells were maintained in Dulbecco's Modified Eagle's Medium and Ham's F-12 Nutrient Mixture (DMEM/F12) supplemented with antibiotics, fetal bovine serum (FBS), 2-mercaptoethanol (2-Me), N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES), and basic fibroblast growth factor (bFGF). The optimal growth temperature for JFSK_wt and JFSK_alb cells was 24 °C, and microscopically, the two cell lines were composed of fibroblast-like cells. Chromosomal analysis revealed that JFSK_wt and JFSK_alb cells had an identical diploid karyotype with 2n = 48t. Results of viral inoculation assays revealed that both cell lines shared similar patterns of viral susceptibility to nervous necrosis virus (NNV). High transfection efficiency was observed in JFSK_wt and JFSK_alb cells transfected with a pEGFP-N3 reporter plasmid and Cy3-siRNA. The detection of dermal marker Dermo-1 showed that these two cells were both derived from the dermis. Finally, three genes involved in the melanogenesis pathway, including adenylate cyclase type 5 (adcy5), microphthalmia-associated transcription factor (mitf), and endothelin B receptor (ednrb), were downregulated in JFSK_alb versus JFSK_wt cells. Thus, the two cell lines, sampled from skin tissue of wild-type and albino Japanese flounder will be not only helpful for fish pathogen research but also beneficial for albinism-related gene function studies.

  3. Optimization of conditions for gene delivery system based on PEI

    Directory of Open Access Journals (Sweden)

    Roya Cheraghi

    2017-01-01

    Full Text Available Objective(s: PEI based nanoparticle (NP due to dual capabilities of proton sponge and DNA binding is known as powerful tool for nucleic acid delivery to cells. However, serious cytotoxicity and complicated conditions, which govern NPs properties and its interactions with cells practically, hindered achievement to high transfection efficiency. Here, we have tried to optimize the properties of PEI/ firefly luciferase plasmid complexes and cellular condition to improve transfection efficiency. Materials and Methods: For this purpose, firefly luciferase, as a robust gene reporter, was complexed with PEI to prepare NPs with different size and charge. The physicochemical properties of nanoparticles were evaluated using agarose gel retardation and dynamic light scattering.  MCF7 and BT474 cells at different confluency were also transfected with prepared nanoparticles at various concentrations for short and long times. Results: The branched PEI can instantaneously bind to DNA and form cationic NPs. The results demonstrated the production of nanoparticles with size about 100-500 nm dependent on N/P ratio. Moreover, increase of nanoparticles concentration on the cell surface drastically improved the transfection rate, so at a concentration of 30 ng/ìl, the highest transfection efficiency was achieved. On the other side, at confluency between 40-60%, the maximum efficiency was obtained. The result demonstrated that N/P ratio of 12 could establish an optimized ratio between transfection efficiency and cytotoxicity of PEI/plasmid nanoparticles. The increase of NPs N/P ratio led to significant cytotoxicity. Conclusion: Obtained results verified the optimum conditions for PEI based gene delivery in different cell lines.

  4. Visualization of ecdysteroid activity using a reporter gene in the crustacean, Daphnia.

    Science.gov (United States)

    Asada, Miki; Kato, Yasuhiko; Matsuura, Tomoaki; Watanabe, Hajime

    2014-02-01

    Ecdysone is a hormone known to play a pivotal role in crustaceans and insects. In order to evaluate the ecdysone activities in the environment and within the organism, we have developed a biomonitoring Daphnia strain by introducing a reporter gene. In this study, the ecdysone response element was inserted in the upstream region of a reporter gene, and the DNA construct was injected into Daphnia eggs. The expression of the reporter gene was detected during the early embryonic development stage. In addition, when the eggs expressing the reporter gene were exposed to ecdysone, there was enhanced expression of the reporter gene at detectable levels, while the presence of an antagonist led to its downregulation. These results suggested that this system could be potentially developed for monitoring ecdysone activities in media. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Fs-laser-induced Ca2+ concentration change during membrane perforation for cell transfection.

    Science.gov (United States)

    Baumgart, J; Bintig, W; Ngezahayo, A; Lubatschowski, H; Heisterkamp, A

    2010-02-01

    Fs-laser based opto-perforation is a gentle method for gene transfer into sensitive cells such as stem cells or primary cells. The high selectivity and the low damage to the cell lead to a high efficiency of transfection. However, there are side effects which induce stress to the cell due to the exchange of intra- and extracellular media as well as the disintegration of the structure of biomolecules resulting from the laser exposure. Moreover, the mechanisms of the optical transfection are still unclear. In this paper, we present our study on calcium (Ca(2+)) homeostasis during cell surgery, especially during laser induced membrane perforation. We show that the manipulation of cells can induce an increase in the cytosolic Ca(2+) concentration. This increase was not observed if the manipulation of the cells was performed in absence of the extracellular calcium indicating the importance of the Ca(2+) uptake. We found, that the uptake of extracellular Ca(2+) strongly depends on the repetition rate and the irradiation time of the laser pulses. The exposure for several seconds to kHz pulses even induces Ca(2+) induced Ca(2+) release. Dependent on the location of perforation, probably in the vicinity of an intracellular Ca(2+) stock, an instantaneous intracellular Ca(2+) release can be induced. Since Ca(2+) could be involved in negative side effect by cell surgery, we propose an application of the optoperforation technique in nominal Ca(2+)-free external solution.

  6. Cholesterol-conjugated supramolecular assemblies of low generations polyamidoamine dendrimers for enhanced EGFP plasmid DNA transfection

    Energy Technology Data Exchange (ETDEWEB)

    Golkar, Nasim; Samani, Soliman Mohammadi; Tamaddon, Ali Mohammad, E-mail: amtamadon@gmail.com [Shiraz University of Medical Sciences, Department of Pharmaceutics, School of Pharmacy (Iran, Islamic Republic of)

    2016-05-15

    Aimed to prepare an enhanced gene delivery system with low cytotoxicity and high transfection efficiency, various cholesterol-conjugated derivates of low generation polyamidoamine (PAMAM) dendrimers were prepared. The conjugates were characterized by TNBS assay, FTIR, and {sup 1}H-NMR spectroscopy. Self-assembly of the dendrimer conjugates (G1-Chol, G2-Chol, and G3-Chol) was investigated by pyrene assay. Following formation of the complexes between enhanced green fluorescence protein plasmid and the dendrimer conjugates at various N (primary amine)/P (phosphate) mole ratios, plasmid condensation, biologic stability, cytotoxicity, and protein expression were investigated. The conjugates self-assembled into micellar dispersions with the critical micelle concentration values (<50 µg/ml) depending on the dendrimer generation and cholesterol/amine mole ratio. Cholesterol conjugation resulted in higher resistance of the condensed plasmid DNA in a competition assay with heparin sulfate. Also, the transfection efficiency was determined higher for the cholesterol conjugates than unmodified dendrimers in HepG2 cells, showing the highest for G2-Chol at 40 % degree of cholesterol modification (G2-Chol{sub 40 %}) among various dendrimer generations. Interestingly, such conjugate showed a complete protection of plasmid against serum nucleases. Our results confirmed that the cholesterol conjugation to PAMAM dendrimers of low generations bearing little cytotoxicity improves their several physicochemical and biological characteristics required for an enhanced delivery of plasmid DNA into cells.

  7. In vitro non-viral murine pro-neurotrophin 3 gene transfer into rat bone marrow stromal cells.

    Science.gov (United States)

    Darabi, Shahram; Tiraihi, Taki; Delshad, AliReza; Sadeghizadeh, Majid; Khalil, Wisam; Taheri, Taher

    2017-04-15

    Neurotrophin 3 (NT-3) is an important factor for promoting prenatal neural development, as well as regeneration, axogenesis and plasticity in postnatal life. Therapy with NT-3 was reported to improve the condition of patients suffering from degenerative diseases and traumatic injuries, however, the disadvantage of NT-3 protein delivery is its short half-life, thus our alternative approach is the use of NT-3 gene therapy. In this study, the bone marrow stromal cells (BMSCs) were isolated from adult rats, cultured for 4 passages and transfected with either pEGFP-N1 or a constructed vector containing murine proNT-3 (pSecTag2/HygroB-murine proNT-3) using Lipofectamine 2000 followed by Hygromycin B (200mg/kg). The transfection efficiency of the transiently transfected BMSCs was evaluated using the green fluorescence protein containing vector (pEGFP-N1). A quantitative evaluation of the NT-3 expression of mRNA using real time qRT-PCR shows that there was double fold increase in NT-3 gene expression compared with non-transfected BMSCs, also, the culture supernatant yielded double fold increase in NT-3 using ELISA technique, the data were supported by immunoblotting technique. This suggests that the use of this transfection technique can be useful for gene therapy in different neurological disorders with neurodegenerative or traumatic origins. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Off-resonance plasmonic enhanced femtosecond laser optoporation and transfection of cancer cells.

    Science.gov (United States)

    Baumgart, Judith; Humbert, Laure; Boulais, Étienne; Lachaine, Rémi; Lebrun, Jean-Jaques; Meunier, Michel

    2012-03-01

    A femtosecond laser based transfection method using off-resonance plasmonic gold nanoparticles is described. For human cancer melanoma cells, the treatment leads to a very high perforation rate of 70%, transfection efficiency three times higher than for conventional lipofection, and very low toxicity (transfection for skin cancer treatment. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Microsphere-liposome complexes protect adenoviral vectors from neutralising antibody without losses in transfection efficiency, in-vitro.

    Science.gov (United States)

    Steel, Jason C; Cavanagh, Heather M A; Burton, Mark A; Kalle, Wouter H J

    2004-11-01

    Adenoviral vectors have been commonly used in gene therapy protocols but the success of their use is often limited by the induction of host immunity to the vector. Following exposure to the adenoviral vector, adenoviral-specific neutralising antibodies are produced, which limits further administration. This study examines the effectiveness of a novel combination of microspheres and liposomes for the shielding of adenovirus from neutralising antibodies in an in-vitro setting. We show that liposomes are effective in the protection of adenovirus from neutralising antibody and that the conjugation of these complexes to microspheres augments the level of protection. This study further reveals that previously neutralised adenovirus may still be transported into the cell via liposome-cell interactions and is still capable of expressing its genes, making this vector an effective tool for circumvention of the humoral immune response. We also looked at possible side effects of using the complexes, namely increases in cytotoxicity and reductions in transfection efficiency. Our results showed that varying the liposome:adenovirus ratio can reduce the cytotoxicity of the vector as well as increase the transfection efficiency. In addition, in cell lines that are adenoviral competent, transfection efficiencies on par with uncomplexed adenoviral vectors were achievable with the combination vector.

  10. Transplantation of neurotrophin-3-transfected bone marrow mesenchymal stem cells for the repair of spinal cord injury.

    Science.gov (United States)

    Dong, Yuzhen; Yang, Libin; Yang, Lin; Zhao, Hongxing; Zhang, Chao; Wu, Dapeng

    2014-08-15

    Bone marrow mesenchymal stem cell transplantation has been shown to be therapeutic in the repair of spinal cord injury. However, the low survival rate of transplanted bone marrow mesenchymal stem cells in vivo remains a problem. Neurotrophin-3 promotes motor neuron survival and it is hypothesized that its transfection can enhance the therapeutic effect. We show that in vitro transfection of neurotrophin-3 gene increases the number of bone marrow mesenchymal stem cells in the region of spinal cord injury. These results indicate that neurotrophin-3 can promote the survival of bone marrow mesenchymal stem cells transplanted into the region of spinal cord injury and potentially enhance the therapeutic effect in the repair of spinal cord injury.

  11. Gene gun bombardment-mediated expression and translocation of EGFP-tagged GLUT4 in skeletal muscle fibres in vivo

    DEFF Research Database (Denmark)

    Lauritzen, Hans P M M; Reynet, Christine; Schjerling, Peter

    2002-01-01

    the enhanced green fluorescent protein (EGFP) labelling technique with physical transfection methods in vivo: intramuscular plasmid injection or gene gun bombardment. During optimisation experiments with plasmid coding for the EGFP reporter alone EGFP-positive muscle fibres were counted after collagenase...... treatment of in vivo transfected flexor digitorum brevis (FDB) muscles. In contrast to gene gun bombardment, intramuscular injection produced EGFP expression in only a few fibres. Regardless of the transfection technique, EGFP expression was higher in muscles from 2-week-old rats than in those from 6-week......Cellular protein trafficking has been studied to date only in vitro or with techniques that are invasive and have a low time resolution. To establish a gentle method for analysis of glucose transporter-4 (GLUT4) trafficking in vivo in fully differentiated rat skeletal muscle fibres we combined...

  12. Structure-transfection activity relationships in a series of novel cationic lipids with heterocyclic head-groups.

    Science.gov (United States)

    Ivanova, Ekaterina A; Maslov, Mikhail A; Kabilova, Tatyana O; Puchkov, Pavel A; Alekseeva, Anna S; Boldyrev, Ivan A; Vlassov, Valentin V; Serebrennikova, Galina A; Morozova, Nina G; Zenkova, Marina A

    2013-11-07

    Cationic liposomes are promising candidates for the delivery of various therapeutic nucleic acids. Here, we report a convenient synthesis of carbamate-type cationic lipids with various hydrophobic domains (tetradecanol, dialkylglycerol, cholesterol) and positively charged head-groups (pyridinium, N-methylimidazolium, N-methylmorpholinium) and data on the structure-transfection activity relationships. It was found that single-chain lipids possess high surface activity, which correlates with high cytotoxicity due to their ability to disrupt the cellular membrane by combined hydrophobic and electrostatic interactions. Liposomes containing these lipids also display high cytotoxicity with respect to all cell lines. Irrespective of chemical structures, all cationic lipids form liposomes with similar sizes and surface potentials. The characteristics of complexes composed of cationic liposomes and nucleic acids depend mostly on the type of nucleic acid and P/N ratios. In the case of oligodeoxyribonucleotide delivery, the transfection activity depends on the type of cationic head-group regardless of the type of hydrophobic domain: all types of cationic liposomes mediate efficient oligonucleotide transfer into 80-90% of the eukaryotic cells, and liposomes based on lipids with N-methylmorpholinium cationic head-group display the highest transfection activity. In the case of plasmid DNA and siRNA, the type of hydrophobic domain determines the transfection activity: liposomes composed of cholesterol-based lipids were the most efficient in DNA transfer, while liposomes containing glycerol-based lipids exhibited reasonable activity in siRNA delivery under serum-free conditions.

  13. Terminator Operon Reporter: combining a transcription termination switch with reporter technology for improved gene synthesis and synthetic biology applications.

    Science.gov (United States)

    Zampini, Massimiliano; Mur, Luis A J; Rees Stevens, Pauline; Pachebat, Justin A; Newbold, C James; Hayes, Finbarr; Kingston-Smith, Alison

    2016-05-25

    Synthetic biology is characterized by the development of novel and powerful DNA fabrication methods and by the application of engineering principles to biology. The current study describes Terminator Operon Reporter (TOR), a new gene assembly technology based on the conditional activation of a reporter gene in response to sequence errors occurring at the assembly stage of the synthetic element. These errors are monitored by a transcription terminator that is placed between the synthetic gene and reporter gene. Switching of this terminator between active and inactive states dictates the transcription status of the downstream reporter gene to provide a rapid and facile readout of the accuracy of synthetic assembly. Designed specifically and uniquely for the synthesis of protein coding genes in bacteria, TOR allows the rapid and cost-effective fabrication of synthetic constructs by employing oligonucleotides at the most basic purification level (desalted) and without the need for costly and time-consuming post-synthesis correction methods. Thus, TOR streamlines gene assembly approaches, which are central to the future development of synthetic biology.

  14. Transient expression of β-glucuronidase reporter gene in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-18

    May 18, 2009 ... Therefore, special attention must be given to the use of genetic manipulation for .... of gus gene was used as a visual marker in transformation. Bacteria ... selective culture (SC) medium containing 200 mg/l carbenicillin and. 50 mg/l .... clones had caused the difference of host-plant response to bacterial ...

  15. [EFFECT OF RECOMBINANT ADENOVIRUS-BONE MORPHOGENETIC PROTEIN 12 TRANSFECTION ON DIFFERENTIATION OF PERIPHERAL BLOOD MESENCHYMAL STEM CELLS INTO TENDON/LIGAMENT CELLS].

    Science.gov (United States)

    Fu, Weili; Chen, Gang; Tang, Xin; Li, Qi; Ll, Jian

    2015-04-01

    To research the effect of recombinant adenovirus-bone morphogenetic protein 12 (Ad-BMP-12) transfection on the differentiation of peripheral blood mesenchymal stem cells (MSCs) into tendon/ligament cells. Peripheral blood MSCs were isolated from New Zealand rabbits (3-4 months old) and cultured in vitro until passage 3. The recombinant adenoviral vector system was prepared using AdEasy system, then transfected into MSCs at passage 3 (transfected group); untransfected MSCs served as control (untransfected group). The morphological characteristics and growth of transfected cells were observed under inverted phase contrast microscope. The transfection efficiency and green fluorescent protein (GFP) expression were detected by flow cytometry (FCM) and fluorescence microscopy. After cultured for 14 days in vitro, the expressions of tendon/ligament-specific markers were determined by immunohistochemistry and real-time fluorescent quantitative PCR. GFP expression could be observed in peripheral blood MSCs at 8 hours after transfection. At 24 hours after transfection, the cells had clear morphology and grew slowly under inverted phase contrast microscope and almost all expressed GFP at the same field under fluorescence microscopy. FCM analysis showed that the transfection efficiency of the transfected group was 99.57%, while it was 2.46% in the untransfected group. The immunohistochemistry showed that the expression of collagen type I gradually increased with culture time in vitro. Real-time fluorescent quantitative PCR results showed that the mRNA expressions of the tendon/ligament-specific genes (Tenomodulin, Tenascin-C, and Decorin) in the transfected group were significantly higher than those in untransfected group (0.061+/- 0.013 vs. 0.004 +/- 0.002, t = -7.700, P=0.031; 0.029 +/- 0.008 vs. 0.003 +/- 0.001, t = -5.741, P=0.020; 0.679 +/- 0.067 vs. 0.142 +/- 0.024, t = -12.998, P=0.000). Ad-BMP-12 can significantly promote differentiation of peripheral blood MSCs into

  16. Electrotransfer parameters as a tool for controlled and targeted gene expression in skin

    Directory of Open Access Journals (Sweden)

    Spela Kos

    2016-01-01

    Full Text Available Skin is an attractive target for gene electrotransfer. It consists of different cell types that can be transfected, leading to various responses to gene electrotransfer. We demonstrate that these responses could be controlled by selecting the appropriate electrotransfer parameters. Specifically, the application of low or high electric pulses, applied by multi-electrode array, provided the possibility to control the depth of the transfection in the skin, the duration and the level of gene expression, as well as the local or systemic distribution of the transgene. The influence of electric pulse type was first studied using a plasmid encoding a reporter gene (DsRed. Then, plasmids encoding therapeutic genes (IL-12, shRNA against endoglin, shRNA against melanoma cell adhesion molecule were used, and their effects on wound healing and cutaneous B16F10 melanoma tumors were investigated. The high-voltage pulses resulted in gene expression that was restricted to superficial skin layers and induced a local response. In contrast, the low-voltage electric pulses promoted transfection into the deeper skin layers, resulting in prolonged gene expression and higher transgene production, possibly with systemic distribution. Therefore, in the translation into the clinics, it will be of the utmost importance to adjust the electrotransfer parameters for different therapeutic approaches and specific mode of action of the therapeutic gene.

  17. [VEGF165 transfected endothelial progenitor cells mediated by lentivirus alleviated ALI in rats].

    Science.gov (United States)

    He, Zhaohui; He, Huiwei; Lu, Yuanhua; Chen, Zhi; Xu, Fanghua; Wang, Rongsheng; Yang, Chunli

    2017-11-01

    To investigate the protective effects of vascular endothelial growth factor-165 (VEGF165) transfected the endothelial progenitor cells (EPCs) mediated by lentivirus on acute lung injury (ALI) in rats. The mononuclear cells from the male Sprague-Dawley (SD) rats were isolated and cultured to get the EPCs for study. The lentivirus vector carrying the human VEGF165 gene was constructed. According to the random number table method, 90 male SD rats were divided into ALI model group, phosphate buffer solution (PBS) group, EPCs treatment group, none transfected EPCs treatment group and VEGF165 transfected EPCs treatment group, and the rats in each group were subdivided into 4, 12 and 48 hours subgroups, with 6 rats in each subgroup. The rat model of ALI was reproduced by intravenous injection of oleic acid (0.15 μL/g). Then each treatment group was given PBS, EPCs, none transfected EPCs and VEGF165 transfected EPCs respectively with the same volume of 0.2 mL. For the groups with cells, about 1×10 6 cells were contained. Abdominal aortic blood and lung tissue were harvested at 4, 12 and 48 hours. Arterial blood gas analysis was performed. The lung wet/dry weight ratio (W/D) was calculated. The expressions of induced nitric oxide synthase (iNOS), endothelin-1 (ET-1) and VEGF165 were determined by enzyme-linked immunosorbent assay (ELISA). After dyed with hematoxylin-eosin (HE), the lung tissue pathology was observed and the lung injury score was performed. Compared with the ALI model group, the arterial partial pressure of oxygen (PaO 2 ) in EPCs, none transfected EPCs and VEGF165 transfected EPCs treatment groups was significantly increased from 4 hours, and lung W/D, expressions of iNOS and ET-1 were significantly decreased, and VEGF165 expression was significantly increased. Compared with the EPCs treatment group, the increase in PaO 2 , the decrease in lung W/D and expressions of iNOS and ET-1, and the increase in VEGF165 expression in VEGF165 transfected EPCs

  18. Effect of secretory pathway gene overexpression on secretion of a fluorescent reporter protein in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Schalén, Martin; Anyaogu, Diana Chinyere; Hoof, Jakob Blæsbjerg

    2016-01-01

    roles in the process have been identified through transcriptomics. The assignment of function to these genes has been enabled in combination with gene deletion studies. In this work, 14 genes known to play a role in protein secretion in filamentous fungi were overexpressed in Aspergillus nidulans....... The background strain was a fluorescent reporter secreting mRFP. The overall effect of the overexpressions could thus be easily monitored through fluorescence measurements, while the effects on physiology were determined in batch cultivations and surface growth studies. Results: Fourteen protein secretion...... pathway related genes were overexpressed with a tet-ON promoter in the RFP-secreting reporter strain and macromorphology, physiology and protein secretion were monitored when the secretory genes were induced. Overexpression of several of the chosen genes was shown to cause anomalies on growth, micro...

  19. Effect of external and internal factors on the expression of reporter genes driven by the N resistance gene promoter.

    Science.gov (United States)

    Kathiria, Palak; Sidler, Corinne; Woycicki, Rafal; Yao, Youli; Kovalchuk, Igor

    2013-07-01

    The role of resistance (R) genes in plant pathogen interaction has been studied extensively due to its economical impact on agriculture. Interaction between tobacco mosaic virus (TMV) and the N protein from tobacco is one of the most widely used models to understand various aspects of pathogen resistance. The transcription activity governed by N gene promoter is one of the least understood elements of the model. In this study, the N gene promoter was cloned and fused with two different reporter genes, one encoding β-glucuronidase (N::GUS) and another, luciferase (N::LUC). Tobacco plants transformed with the N::GUS or N::LUC reporter constructs were screened for homozygosity and stable expression. Histochemical analysis of N::GUS tobacco plants revealed that the expression is organ specific and developmentally regulated. Whereas two week old plants expressed GUS in midveins only, 6-wk-old plants also expressed GUS in leaf lamella. Roots did not show GUS expression at any time during development. Experiments to address effects of external stress were performed using N::LUC tobacco plants. These experiments showed that N gene promoter expression was suppressed when plants were exposed to high but not low temperatures. Expression was also upregulated in response to TMV, but no changes were observed in plants treated with SA.

  20. Transient expression of β-glucuronidase reporter gene in ...

    African Journals Online (AJOL)

    Agrobacterium tumefaciens strain LBA4404 carrying the pBI.121 binary plasmid was used in transformation to introduce the gus (ß-glucuronidase/GUS) gene into teak shoot-tissues. In vitro regenerated shoots from various teak clones, i.e. the ITB, GT, P97, P96, P75, P20, and P108 clones were vacuum-infiltrated for 5 min in ...

  1. Transfection of primary brain capillary endothelial cells for protein synthesis and secretion of recombinant erythropoietin: a strategy to enable protein delivery to the brain

    DEFF Research Database (Denmark)

    Burkhart, Annette; Andresen, Thomas Lars; Aigner, Achim

    2017-01-01

    , as turning BCECs into recombinant protein factories by transfection could result in protein secretion further into the brain. The present study aims to investigate the possibility of transfecting primary rat brain endothelial cells (RBECs) for recombinant protein synthesis and secretion...... of the neuroprotective protein erythropoietin (EPO). We previously showed that 4% of RBECs with BBB properties can be transfected without disrupting the BBB integrity in vitro, but it can be questioned whether this is sufficient to enable protein secretion at therapeutic levels. The present study examined various......-derived neurotropic factor (BDNF). In conclusion, non-viral gene therapy to RBECs leads to protein secretion and signifies a method for therapeutic proteins to target cells inside the CNS otherwise omitted due to the BBB....

  2. Mechanisms of recombination and function of DNA in bacteria. Progress report, May 3, 1975--May 5, 1976

    International Nuclear Information System (INIS)

    Guild, W.R.

    1976-01-01

    Results of investigations on phages were obtained with regard to the finding of transfection and characterizing the mode of entry of transfecting DNA; the characterization of a DNAase-resistant gene transfer agent from phage-infected cells which has some of the properties of a generalized transducing phage; and the study of multiplicity reactivation of uv-irradiated phage in a uv-sensitive pneumococcal host. Progress is also reported on a new gene transfer process, cell mutants, fine structure mapping, and stimulated recombination

  3. Dual-therapeutic reporter genes fusion for enhanced cancer gene therapy and imaging.

    Science.gov (United States)

    Sekar, T V; Foygel, K; Willmann, J K; Paulmurugan, R

    2013-05-01

    Two of the successful gene-directed enzyme prodrug therapies include herpes simplex virus-thymidine kinase (HSV1-TK) enzyme-ganciclovir prodrug and the Escherichia coli nitroreductase (NTR) enzyme-CB1954 prodrug strategies; these enzyme-prodrug combinations produce activated cytotoxic metabolites of the prodrugs capable of tumor cell death by inhibiting DNA synthesis and killing quiescent cells, respectively. Both these strategies also affect significant bystander cell killing of neighboring tumor cells that do not express these enzymes. We have developed a dual-combination gene strategy, where we identified HSV1-TK and NTR fused in a particular orientation can effectively kill tumor cells when the tumor cells are treated with a fusion HSV1-TK-NTR gene- along with a prodrug combination of GCV and CB1954. In order to determine whether the dual-system demonstrate superior therapeutic efficacy than either HSV1-TK or NTR systems alone, we conducted both in vitro and in vivo tumor xenograft studies using triple negative SUM159 breast cancer cells, by evaluating the efficacy of cell death by apoptosis and necrosis upon treatment with the dual HSV1-TK genes-GCV-CB1954 prodrugs system, and compared the efficiency to HSV1-TK-GCV and NTR-CB1954. Our cell-based studies, tumor regression studies in xenograft mice, histological analyses of treated tumors and bystander studies indicate that the dual HSV1-TK-NTR-prodrug system is two times more efficient even with half the doses of both prodrugs than the respective single gene-prodrug system, as evidenced by enhanced apoptosis and necrosis of tumor cells in vitro in culture and xenograft of tumor tissues in animals.

  4. The experimental study of reporter probe 131I-FIAU in neonatal cardiac myocytes after transfer of herpes simplex virus type 1 thymidine kinase reporter gene by different vectors

    International Nuclear Information System (INIS)

    Yin Xiaohua; Lan Xiaoli; Wang Ruihua; Liu Ying; Zhang Yongxue

    2009-01-01

    accumulation of 131 I-F1AU for Ad5-tk infected cells compared with pDC316-tk/lipoplex transfected ones occurred for all the time points (t=12.978-38.253. all P<0.01). When 24h after transferred. the cardiac myocytes showed significant expression of HSVI-tk mRNA. while the control groups showed negative. Moreover, the exogenous gene expression in the adenovirus vector-infected cardiac. myocytes was significantly higher than in the pDC316-tk/lipoplex-transducted ones (3.11 ± 0.14 vs1.60 ± 0.05, t=17.663, P<0.01). Immunocytochemistry showed that the transferred cardiac myocytes successfully expressed the target protein, and the positive rate was (81.70 ± 0.40)% and (22.06 ± 0.32)% respectively, and there was also significant difference between them (t=23.237, P<0.01). Conclusions: Both vectors could transfer the reporter gene into the cardiac myocytes successfully, and the expressed exogenous protein could form a functional enzyme as to uptake the reporter probe much efficiently. But the transferred cardiac myocytes mediated by the adenovirus vector acted even more efficiently than the ones mediated by liposome-coated plasmid with higher uptake rate. Thus the adenovirus was competent for the gene transfer in cardiac reporter gene imaging. (authors)

  5. Combinatorial treatment with lithium chloride enhances recombinant antibody production in transiently transfected CHO and HEK293E cells

    DEFF Research Database (Denmark)

    Kim, Che Lin; Kwang Ha, Tae; Min Lee, Gyun

    2016-01-01

    Lithium chloride (LiCl), which induces cell cycle arrest at G2/M phase, is known as a specific production rate (qp)-enhancing additive in recombinant Chinese hamster ovary (CHO) cell culture. To determine the potential of LiCl as a chemical additive that enhances transient gene expression (TGE), Li......Cl was added to the CHO-NK and human embryonic kidney 293E (HEK293E) cell cultures before and/or after transfection with polyethylenimine as a transfection reagent. The effect of this addition on transfection efficiency (pre-treatment) and qp enhancement during TGE (post-treatment) was examined. For the TGE...... of monoclonal antibody (mAb) in CHO-NK cells, pretreatment alone with 10 mM LiCl and post-treatment alone with 5 mM LiCl resulted in 1.2- and 3.4-fold increase of maximum mAb concentration (MMC), respectively, compared with the TGE without LiCl treatment. Furthermore, combinatorial treatment with LiCl (10 m...

  6. Reduction of adenovirus E1A mRNA by RNAi results in enhanced recombinant protein expression in transiently transfected HEK293 cells.

    Science.gov (United States)

    Hacker, David L; Bertschinger, Martin; Baldi, Lucia; Wurm, Florian M

    2004-10-27

    Human embryonic kidney 293 (HEK293) cells, a widely used host for large-scale transient expression of recombinant proteins, are transformed with the adenovirus E1A and E1B genes. Because the E1A proteins function as transcriptional activators or repressors, they may have a positive or negative effect on transient transgene expression in this cell line. Suspension cultures of HEK293 EBNA (HEK293E) cells were co-transfected with a reporter plasmid expressing the GFP gene and a plasmid expressing a short hairpin RNA (shRNA) targeting the E1A mRNAs for degradation by RNA interference (RNAi). The presence of the shRNA in HEK293E cells reduced the steady state level of E1A mRNA up to 75% and increased transient GFP expression from either the elongation factor-1alpha (EF-1alpha) promoter or the human cytomegalovirus (HCMV) immediate early promoter up to twofold. E1A mRNA depletion also resulted in a twofold increase in transient expression of a recombinant IgG in both small- and large-scale suspension cultures when the IgG light and heavy chain genes were controlled by the EF-1alpha promoter. Finally, transient IgG expression was enhanced 2.5-fold when the anti-E1A shRNA was expressed from the same vector as the IgG light chain gene. These results demonstrated that E1A has a negative effect on transient gene expression in HEK293E cells, and they established that RNAi can be used to enhance recombinant protein expression in mammalian cells.

  7. Naturally occurring mutations in the human 5-lipoxygenase gene promoter that modify transcription factor binding and reporter gene transcription.

    Science.gov (United States)

    In, K H; Asano, K; Beier, D; Grobholz, J; Finn, P W; Silverman, E K; Silverman, E S; Collins, T; Fischer, A R; Keith, T P; Serino, K; Kim, S W; De Sanctis, G T; Yandava, C; Pillari, A; Rubin, P; Kemp, J; Israel, E; Busse, W; Ledford, D; Murray, J J; Segal, A; Tinkleman, D; Drazen, J M

    1997-03-01

    Five lipoxygenase (5-LO) is the first committed enzyme in the metabolic pathway leading to the synthesis of the leukotrienes. We examined genomic DNA isolated from 25 normal subjects and 31 patients with asthma (6 of whom had aspirin-sensitive asthma) for mutations in the known transcription factor binding regions and the protein encoding region of the 5-LO gene. A family of mutations in the G + C-rich transcription factor binding region was identified consisting of the deletion of one, deletion of two, or addition of one zinc finger (Sp1/Egr-1) binding sites in the region 176 to 147 bp upstream from the ATG translation start site where there are normally 5 Sp1 binding motifs in tandem. Reporter gene activity directed by any of the mutant forms of the transcription factor binding region was significantly (P < 0.05) less effective than the activity driven by the wild type transcription factor binding region. Electrophoretic mobility shift assays (EMSAs) demonstrated the capacity of wild type and mutant transcription factor binding regions to bind nuclear extracts from human umbilical vein endothelial cells (HUVECs). These data are consistent with a family of mutations in the 5-LO gene that can modify reporter gene transcription possibly through differences in Sp1 and Egr-1 transactivation.

  8. Development and evaluation of an efficient heterologous gene knock-in reporter system in Lactococcus lactis.

    Science.gov (United States)

    Lu, Yifei; Yan, Hongxiang; Deng, Jiezhong; Huang, Zhigang; Jin, Xurui; Yu, Yanlan; Hu, Qiwen; Hu, Fuquan; Wang, Jing

    2017-09-18

    Lactococcus lactis is a food grade probiotics and widely used to express heterologous proteins. Generally, target genes are knocked into the L. lactis genome through double-crossover recombination to express heterologous proteins stably. However, creating marker-less heterologous genes knocked-in clones is laborious. In this study, an efficient heterologous gene knock-in reporter system was developed in L. lactis NZ9000. Our knock-in reporter system consists of a temperature-sensitive plasmid pJW and a recombinant L. lactis strain named NZB. The pJW contains homologous arms, and was constructed to knock-in heterologous genes at a fixed locus of NZ9000 genome. lacZ (β-galactosidase) gene was knocked into the chromosome of NZ9000 as a counter-selective marker through the plasmid pJW to generate NZB. The engineered NZB strain formed blue colonies on X-Gal plate. The desired double-crossover mutants formed white colonies distinctive from the predominantly blue colonies (parental and plasmid-integrated clones) when the embedded lacZ was replaced with the target heterologous genes carried by pJW in NZB. By using the system, the heterologous gene knocked-in clones are screened by colony phenotype change rather than by checking colonies individually. Our new knock-in reporter system provides an efficient method to create heterologous genes knocked-in clones.

  9. A novel binary T-vector with the GFP reporter gene for promoter characterization.

    Directory of Open Access Journals (Sweden)

    Shu-Ye Jiang

    Full Text Available Several strategies have been developed to clone PCR fragments into desired vectors. However, most of commercially available T-vectors are not binary vectors and cannot be directly used for Agrobacterium-mediated plant genetic transformation. In this study, a novel binary T-vector was constructed by integrating two AhdI restriction sites into the backbone vector pCAMBIA 1300. The T-vector also contains a GFP reporter gene and thus, can be used to analyze promoter activity by monitoring the reporter gene. On the other hand, identification and characterization of various promoters not only benefit the functional annotation of their genes but also provide alternative candidates to be used to drive interesting genes for plant genetic improvement by transgenesis. More than 1,000 putative pollen-specific rice genes have been identified in a genome-wide level. Among them, 67 highly expressed genes were further characterized. One of the pollen-specific genes LOC_Os10g35930 was further surveyed in its expression patterns with more details by quantitative real-time reverse-transcription PCR (qRT-PCR analysis. Finally, its promoter activity was further investigated by analyzing transgenic rice plants carrying the promoter::GFP cassette, which was constructed from the newly developed T-vector. The reporter GFP gene expression in these transgenic plants showed that the promoter was active only in mature but not in germinated pollens.

  10. Functionalization with C-terminal cysteine enhances transfection efficiency of cell-penetrating peptides through dimer formation

    Energy Technology Data Exchange (ETDEWEB)

    Amand, Helene L., E-mail: helene.amand@chalmers.se [Chalmers University of Technology, Department of Chemical and Biological Engineering/Physical Chemistry, SE-412 96 Gothenburg (Sweden); Norden, Bengt, E-mail: norden@chalmers.se [Chalmers University of Technology, Department of Chemical and Biological Engineering/Physical Chemistry, SE-412 96 Gothenburg (Sweden); Fant, Kristina, E-mail: kristina.fant@sp.se [Chalmers University of Technology, Department of Chemical and Biological Engineering/Physical Chemistry, SE-412 96 Gothenburg (Sweden)

    2012-02-17

    Highlights: Black-Right-Pointing-Pointer Reversible CPP dimerisation is a simple yet efficient strategy to improve delivery. Black-Right-Pointing-Pointer Dimer formation enhances peptiplex stability, resulting in increased transfection. Black-Right-Pointing-Pointer By dimerisation, the CPP EB1 even gain endosomal escape properties while lowering cytotoxicity. -- Abstract: Cell-penetrating peptides have the ability to stimulate uptake of macromolecular cargo in mammalian cells in a non-toxic manner and therefore hold promise as efficient and well tolerated gene delivery vectors. Non-covalent peptide-DNA complexes ('peptiplexes') enter cells via endocytosis, but poor peptiplex stability and endosomal entrapment are considered as main barriers to peptide-mediated delivery. We explore a simple, yet highly efficient, strategy to improve the function of peptide-based vectors, by adding one terminal cysteine residue. This allows the peptide to dimerize by disulfide bond formation, increasing its affinity for nucleic acids by the 'chelate effect' and, when the bond is reduced intracellularly, letting the complex dissociate to deliver the nucleic acid. By introducing a single C-terminal cysteine in the classical CPP penetratin and the penetratin analogs PenArg and EB1, we show that this minor modification greatly enhances the transfection capacity for plasmid DNA in HEK293T cells. We conclude that this effect is mainly due to enhanced thermodynamic stability of the peptiplexes as endosome-disruptive chloroquine is still required for transfection and the effect is more pronounced for peptides with lower inherent DNA condensation capacity. Interestingly, for EB1, addition of one cysteine makes the peptide able to mediate transfection in absence of chloroquine, indicating that dimerisation can also improve endosomal escape properties. Further, the cytotoxicity of EB1 peptiplexes is considerably reduced, possibly due to lower concentration of free peptide

  11. Functionalization with C-terminal cysteine enhances transfection efficiency of cell-penetrating peptides through dimer formation

    International Nuclear Information System (INIS)

    Åmand, Helene L.; Nordén, Bengt; Fant, Kristina

    2012-01-01

    Highlights: ► Reversible CPP dimerisation is a simple yet efficient strategy to improve delivery. ► Dimer formation enhances peptiplex stability, resulting in increased transfection. ► By dimerisation, the CPP EB1 even gain endosomal escape properties while lowering cytotoxicity. -- Abstract: Cell-penetrating peptides have the ability to stimulate uptake of macromolecular cargo in mammalian cells in a non-toxic manner and therefore hold promise as efficient and well tolerated gene delivery vectors. Non-covalent peptide-DNA complexes (“peptiplexes”) enter cells via endocytosis, but poor peptiplex stability and endosomal entrapment are considered as main barriers to peptide-mediated delivery. We explore a simple, yet highly efficient, strategy to improve the function of peptide-based vectors, by adding one terminal cysteine residue. This allows the peptide to dimerize by disulfide bond formation, increasing its affinity for nucleic acids by the “chelate effect” and, when the bond is reduced intracellularly, letting the complex dissociate to deliver the nucleic acid. By introducing a single C-terminal cysteine in the classical CPP penetratin and the penetratin analogs PenArg and EB1, we show that this minor modification greatly enhances the transfection capacity for plasmid DNA in HEK293T cells. We conclude that this effect is mainly due to enhanced thermodynamic stability of the peptiplexes as endosome-disruptive chloroquine is still required for transfection and the effect is more pronounced for peptides with lower inherent DNA condensation capacity. Interestingly, for EB1, addition of one cysteine makes the peptide able to mediate transfection in absence of chloroquine, indicating that dimerisation can also improve endosomal escape properties. Further, the cytotoxicity of EB1 peptiplexes is considerably reduced, possibly due to lower concentration of free peptide dimer resulting from its stronger binding to DNA.

  12. Immune monitoring using mRNA-transfected dendritic cells

    DEFF Research Database (Denmark)

    Borch, Troels Holz; Svane, Inge Marie; Met, Özcan

    2016-01-01

    Dendritic cells are known to be the most potent antigen presenting cell in the immune system and are used as cellular adjuvants in therapeutic anticancer vaccines using various tumor-associated antigens or their derivatives. One way of loading antigen into the dendritic cells is by m......RNA electroporation, ensuring presentation of antigen through major histocompatibility complex I and potentially activating T cells, enabling them to kill the tumor cells. Despite extensive research in the field, only one dendritic cell-based vaccine has been approved. There is therefore a great need to elucidate...... and understand the immunological impact of dendritic cell vaccination in order to improve clinical benefit. In this chapter, we describe a method for performing immune monitoring using peripheral blood mononuclear cells and autologous dendritic cells transfected with tumor-associated antigen-encoding mRNA....

  13. The E-screen test and the MELN gene-reporter assay used for determination of estrogenic activity in fruits and vegetables in relation to pesticide residues.

    Science.gov (United States)

    Schilirò, Tiziana; Porfido, Arianna; Longo, Annalisa; Coluccia, Sara; Gilli, Giorgio

    2013-12-01

    Endocrine-disrupting chemicals (EDCs) may lead to adverse systemic effects by interfering with normal hormone homeostasis, and diet is considered to be among the main routes of EDC exposure. The present study investigated the total estrogenic activity of fruits and vegetables by calculating the 17-β-estradiol equivalent quantity (EEQ) using two in vitro tests: the human breast cancer cell line (MCF-7 BUS) proliferation assay (E-screen test) and the luciferase-transfected human breast cancer cell line (MELN) gene-reporter assay. Of the 24 analyzed fruits and vegetables, 14 contained from 1 to 4 pesticide residues in concentrations ranging from 0.02 to 1.19 ppm, whereas the other 10 did not contain any pesticide residues. The EEQ values for all positive samples ranged from 0.010 to 0.616 μg/100g for the above in vitro tests. Our study demonstrates that estrogenic activity was present in fruits and vegetables and that the concentration of allowable pesticide residues and EEQ values were positively correlated; however, no correlation was found by comparing the estrogenic activity and the intrinsic content of phytoestrogens obtained from the available literature. A theoretical adult dietary intake of 0.7-0.9 ng EEQ/L/day from fruits and vegetables was calculated. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Structure-function relationships of new lipids designed for DNA transfection.

    Science.gov (United States)

    Dittrich, Matthias; Heinze, Martin; Wölk, Christian; Funari, Sergio S; Dobner, Bodo; Möhwald, Helmuth; Brezesinski, Gerald

    2011-08-22

    Cationic liposome/DNA complexes can be used as nonviral vectors for direct delivery of DNA-based biopharmaceuticals to damaged cells and tissues. To obtain more effective and safer liposome-based gene transfection systems, two cationic lipids with identical head groups but different chain structures are investigated with respect to their in vitro gene-transfer activity, their cell-damaging characteristics, and their physicochemical properties. The gene-transfer activities of the two lipids are very different. Differential scanning calorimetry and synchrotron small- and wide-angle X-ray scattering give valuable structural insight. A subgel-like structure with high packing density and high phase-transition temperature from gel to liquid-crystalline state are found for lipid 7 (N'-2-[(2,6-diamino-1-oxohexyl)amino]ethyl-2,N-bis(hexadecyl)propanediamide) containing two saturated chains. Additionally, an ordered head-group lattice based on formation of a hydrogen-bond network is present. In contrast, lipid 8 (N'-2-[(2,6-diamino-1-oxohexyl)amino]ethyl-2-hexadecyl-N-[(9Z)-octadec-9-enyl]propanediamide) with one unsaturated and one saturated chain shows a lower phase-transition temperature and a reduced packing density. These properties enhance incorporation of the helper lipid cholesterol needed for gene transfection. Both lipids, either pure or in mixtures with cholesterol, form lamellar phases, which are preserved after addition of DNA. However, the system separates into phases containing DNA and phases without DNA. On increasing the temperature, DNA is released and only a lipid phase without intercalated DNA strands is observed. The conversion temperatures are very different in the two systems studied. The important parameter seems to be the charge density of the lipid membranes, which is a result of different solubility of cholesterol in the two lipid membranes. Therefore, different binding affinities of the DNA to the lipid mixtures are achieved. Copyright © 2011

  15. Non-invasive imaging using reporter genes altering cellular water permeability

    Science.gov (United States)

    Mukherjee, Arnab; Wu, Di; Davis, Hunter C.; Shapiro, Mikhail G.

    2016-12-01

    Non-invasive imaging of gene expression in live, optically opaque animals is important for multiple applications, including monitoring of genetic circuits and tracking of cell-based therapeutics. Magnetic resonance imaging (MRI) could enable such monitoring with high spatiotemporal resolution. However, existing MRI reporter genes based on metalloproteins or chemical exchange probes are limited by their reliance on metals or relatively low sensitivity. Here we introduce a new class of MRI reporters based on the human water channel aquaporin 1. We show that aquaporin overexpression produces contrast in diffusion-weighted MRI by increasing tissue water diffusivity without affecting viability. Low aquaporin levels or mixed populations comprising as few as 10% aquaporin-expressing cells are sufficient to produce MRI contrast. We characterize this new contrast mechanism through experiments and simulations, and demonstrate its utility in vivo by imaging gene expression in tumours. Our results establish an alternative class of sensitive, metal-free reporter genes for non-invasive imaging.

  16. Transfection of primary brain capillary endothelial cells for protein synthesis and secretion of recombinant erythropoietin: a strategy to enable protein delivery to the brain.

    Science.gov (United States)

    Burkhart, Annette; Andresen, Thomas Lars; Aigner, Achim; Thomsen, Louiza Bohn; Moos, Torben

    2017-07-01

    Treatment of chronic disorders affecting the central nervous system (CNS) is complicated by the inability of drugs to cross the blood-brain barrier (BBB). Non-viral gene therapy applied to brain capillary endothelial cells (BCECs) denotes a novel approach to overcome the restraints in this passage, as turning BCECs into recombinant protein factories by transfection could result in protein secretion further into the brain. The present study aims to investigate the possibility of transfecting primary rat brain endothelial cells (RBECs) for recombinant protein synthesis and secretion of the neuroprotective protein erythropoietin (EPO). We previously showed that 4% of RBECs with BBB properties can be transfected without disrupting the BBB integrity in vitro, but it can be questioned whether this is sufficient to enable protein secretion at therapeutic levels. The present study examined various transfection vectors, with regard to increasing the transfection efficiency without disrupting the BBB integrity. Lipofectamine 3000™ was the most potent vector compared to polyethylenimine (PEI) and Turbofect. When co-cultured with astrocytes, the genetically modified RBECs secreted recombinant EPO into the cell culture medium both luminally and abluminally, and despite lower levels of EPO reaching the abluminal chamber, the amount of recombinant EPO was sufficient to evolve a biological effect on astrocytes cultured at the abluminal side in terms of upregulated gene expression of brain-derived neurotropic factor (BDNF). In conclusion, non-viral gene therapy to RBECs leads to protein secretion and signifies a method for therapeutic proteins to target cells inside the CNS otherwise omitted due to the BBB.

  17. Lethal effects of 32P decay on transfecting activity of Bacillus subtillis phage phie DNA

    International Nuclear Information System (INIS)

    Loveday, K.S.

    1979-01-01

    Disintegration of 32 P present in the DNA of Bacillus subtilis phage phie (a phage containing double-strand DNA) results in the loss of viability of intact phage as well as transfecting activity of isolated DNA. Only 1/12 of the 32 P disintegrations per phage DNA equivalent inactivities the intact phage while nearly every disintegration inactivates the transfecting DNA. This result provides evidence for a single-strand intermediate in the transfection of B. subtilis by phie DNA

  18. Combination of Heavy-ion radiotherapy and p53-gene therapy by radio-sensitizing promoter for glioma

    International Nuclear Information System (INIS)

    Oga, Masaru; Koshikawa, Nobuko; Takenaga, Keizo; Iwadate, Yasuo; Nojima, Kumie

    2005-01-01

    In this study we have investigated the anti-tumor effect of the combination of heavy-ion radiotherapy, inducing p53-independent apoptosis, and p53-gene therapy, inducing p53-dependent apoptosis for glioma. To enhance the p53-dependent apoptosis, we chose the strategy to utilize the heavy-ion irradiation itself as a ''trigger'' by using radio-sensitizing promoter-E9ns-2/CMV chimeric promoter (Scott et al:2003) in p53-gene therapy. First, EGFP reporter gene with E9ns-2/CMV chimeric promoter was transfected in C6 rat glioma cell-line and the transfected-cell bulk was irradiated at dose of 3, 5, 10 Gy respectively with charged carbon particle (290 MeV/nucleon). The light upregulation of EGFP was observed in 24 hours after 5 Gy irradiation. On the basis of this result, p53 gene with E9ns-2/CMV chimeric promoter was transfected in p53-mutant U373MG human glioma cell-line and the transfected-cell bulk was irradiated at dose of 5 Gy. There was, however, no obvious p53-upregulation at any time-point, so far. Further investigation is needed to clarify the appropriate experimental system. (author)

  19. Efficient transfection of DNA into primarily cultured rat sertoli cells by electroporation.

    Science.gov (United States)

    Li, Fuping; Yamaguchi, Kohei; Okada, Keisuke; Matsushita, Kei; Enatsu, Noritoshi; Chiba, Koji; Yue, Huanxun; Fujisawa, Masato

    2013-03-01

    The expression of exogenous DNA in Sertoli cells is essential for studying its functional genomics, pathway analysis, and medical applications. Electroporation is a valuable tool for nucleic acid delivery, even in primarily cultured cells, which are considered difficult to transfect. In this study, we developed an optimized protocol for electroporation-based transfection of Sertoli cells and compared its efficiency with conventional lipofection. Sertoli cells were transfected with pCMV-GFP plasmid by square-wave electroporation under different conditions. After transfection of plasmid into Sertoli cells, enhanced green fluorescent protein (EGFP) expression could be easily detected by fluorescent microscopy, and cell survival was evaluated by dye exclusion assay using Trypan blue. In terms of both cell survival and the percentage expressing EGFP, 250 V was determined to produce the greatest number of transiently transfected cells. Keeping the voltage constant (250 V), relatively high cell survival (76.5% ± 3.4%) and transfection efficiency (30.6% ± 5.6%) were observed with a pulse length of 20 μm. The number of pulses significantly affected cell survival and EGFP expression (P transfection methods, the transfection efficiency of electroporation (21.5% ± 5.7%) was significantly higher than those of Lipofectamine 2000 (2.9% ± 1.0%) and Effectene (1.9% ± 0.8%) in this experiment (P transfection of Sertoli cells.

  20. Evaluating the role of low-speed centrifugation towards transfecting human peripheral blood mononuclear cell culture.

    Science.gov (United States)

    Majumdar, M; Ratho, R; Chawla, Y; Singh, M P

    2014-01-01

    The conventional method of transfection of suspension cells by chemical has proven to be very difficult. We present a new transfection protocol, wherein, low-speed centrifugation of cell culture plates immediately after adding the lipid: DNA complex significantly enhances the transfection efficiency. Peripheral blood mononuclear cells (PBMCs) were transfected with BLOCK-iT™ Fluorescent Oligo (scrambled siRNA) and lipofectamine complex using conventional and low-speed centrifugation modified transfection protocols. The efficiency of transfection was determined using flowcytometer and cell viability was checked using MTT assay. Incorporation of low-speed centrifugation significantly enhances the transfection efficiency of BLOCK-iT™ in the suspension culture of PBMCs as compared to conventional transfection method (99.8% vs 28.3%; P Centrifugation enhanced transfection (CET) technique is simple, time-saving and novel application without compromising the cell viability in the context of recently popular RNA interference in suspension cultures of PBMCs. This undemanding modification might be applicable to a wide variety of cell lines and solve crucial problem of researchers working with RNA interference in suspension cultures.

  1. Evaluating the role of low-speed centrifugation towards transfecting human peripheral blood mononuclear cell culture

    Directory of Open Access Journals (Sweden)

    M Majumdar

    2014-01-01

    Full Text Available The conventional method of transfection of suspension cells by chemical has proven to be very difficult. We present a new transfection protocol, wherein, low-speed centrifugation of cell culture plates immediately after adding the lipid: DNA complex significantly enhances the transfection efficiency. Peripheral blood mononuclear cells (PBMCs were transfected with BLOCK-iT™ Fluorescent Oligo (scrambled siRNA and lipofectamine complex using conventional and low-speed centrifugation modified transfection protocols. The efficiency of transfection was determined using flowcytometer and cell viability was checked using MTT assay. Incorporation of low-speed centrifugation significantly enhances the transfection efficiency of BLOCK-iT™ in the suspension culture of PBMCs as compared to conventional transfection method (99.8% vs 28.3%; P < 0.0001, even at a low concentration of 40 picomoles without affecting the cell viability. Centrifugation enhanced transfection (CET technique is simple, time-saving and novel application without compromising the cell viability in the context of recently popular RNA interference in suspension cultures of PBMCs. This undemanding modification might be applicable to a wide variety of cell lines and solve crucial problem of researchers working with RNA interference in suspension cultures.

  2. Adenoviral gene delivery to primary human cutaneous cells and burn wounds.

    Science.gov (United States)

    Hirsch, Tobias; von Peter, Sebastian; Dubin, Grzegorz; Mittler, Dominik; Jacobsen, Frank; Lehnhardt, Markus; Eriksson, Elof; Steinau, Hans-Ulrich; Steinstraesser, Lars

    2006-01-01

    The adenoviral transfer of therapeutic genes into epidermal and dermal cells is an interesting approach to treat skin diseases and to promote wound healing. The aim of this study was to assess the in vitro and in vivo transfection efficacy in skin and burn wounds after adenoviral gene delivery. Primary keratinocytes (HKC), fibroblasts (HFB), and HaCaT cells were transfected using different concentrations of an adenoviral construct (eGFP). Transfection efficiency and cytotoxicity was determined up to 30 days. Expression was quantified by FACS analysis and fluorimeter. Cytotoxicity was measured using the trypan blue exclusion method. 45 male Sprague Dawley rats received 2x10(8) pfu of Ad5-CMV-LacZ or carrier control intradermally into either superficial partial thickness scald burn or unburned skin. Animals were euthanized after 48 h, 7 or 14 days posttreatment. Transgene expression was assessed using immunohistochemistry and bioluminescent assays. The highest transfection rate was observed 48 h posttransfection: 79% for HKC, 70% for HFB, and 48% for HaCaT. The eGFP expression was detectable in all groups over 30 days (P>0.05). Cytotoxic effects of the adenoviral vector were observed for HFB after 10 days and HaCaT after 30 days. Reporter gene expression in vivo was significantly higher in burned skin compared with unburned skin (P=0,004). Gene expression decreases from 2 to 7 days with no significant expression after 14 days. This study demonstrates that effective adenoviral-mediated gene transfer of epidermal primary cells and cell-lines is feasible. Ex vivo gene transfer in epithelial cells might have promise for the use in severely burned patients who receive autologous keratinocyte sheets. Transient cutaneous gene delivery in burn wounds using adenoviral vectors causes significant concentrations in the wound tissue for at least 1 week. Based on these findings, we hypothesize that transient cutaneous adenoviral gene delivery of wound healing promoting factors has

  3. Identification of a novel CLRN1 gene mutation in Usher syndrome type 3: two case reports.

    Science.gov (United States)

    Yoshimura, Hidekane; Oshikawa, Chie; Nakayama, Jun; Moteki, Hideaki; Usami, Shin-Ichi

    2015-05-01

    This study examines the CLRN1 gene mutation analysis in Japanese patients who were diagnosed with Usher syndrome type 3 (USH3) on the basis of clinical findings. Genetic analysis using massively parallel DNA sequencing (MPS) was conducted to search for 9 causative USH genes in 2 USH3 patients. We identified the novel pathogenic mutation in the CLRN1 gene in 2 patients. The missense mutation was confirmed by functional prediction software and segregation analysis. Both patients were diagnosed as having USH3 caused by the CLRN1 gene mutation. This is the first report of USH3 with a CLRN1 gene mutation in Asian populations. Validating the presence of clinical findings is imperative for properly differentiating among USH subtypes. In addition, mutation screening using MPS enables the identification of causative mutations in USH. The clinical diagnosis of this phenotypically variable disease can then be confirmed. © The Author(s) 2015.

  4. Oestrogenic activity of a textile industrial wastewater treatment plant effluent evaluated by the E-screen test and MELN gene-reporter luciferase assay

    Energy Technology Data Exchange (ETDEWEB)

    Schiliro, Tiziana, E-mail: tiziana.schiliro@unito.it [Department of Public Health and Microbiology, University of Torino, Via Santena 5bis, 10126 Torino (Italy); Porfido, Arianna [Department of Public Health and Microbiology, University of Torino, Via Santena 5bis, 10126 Torino (Italy); Spina, Federica; Varese, Giovanna Cristina [Department of Life Sciences and Systems Biology, University of Torino, Viale Mattioli 25, 10125 Torino (Italy); Gilli, Giorgio [Department of Public Health and Microbiology, University of Torino, Via Santena 5bis, 10126 Torino (Italy)

    2012-08-15

    This study quantified the biological oestrogenic activity in the effluent of a textile industrial wastewater treatment plant (IWWTP) in northwestern Italy. Samples of the IWWTP effluent were collected monthly, both before and after tertiary treatment (ozonation). After solid phase extraction, all samples were subjected to two in vitro tests of total estrogenic activity, the human breast cancer cell line (MCF-7 BUS) proliferation assay, or E-screen test, and the luciferase-transfected human breast cancer cell line (MELN) gene-reporter assay, to measure the 17{beta}-oestradiol equivalent quantity (EEQ). In the E-screen test, the mean EEQ values were 2.35 {+-} 1.68 ng/L pre-ozonation and 0.72 {+-} 0.58 ng/L post-ozonation; in the MELN gene-reporter luciferase assay, the mean EEQ values were 4.18 {+-} 3.54 ng/L pre-ozonation and 2.53 {+-} 2.48 ng/L post-ozonation. These results suggest that the post-ozonation IWWTP effluent had a lower oestrogenic activity (simple paired t-tests, p < 0.05). The average reduction of estrogenic activity of IWWTP effluent after ozonation was 67 {+-} 26% and 52 {+-} 27% as measured by E-screen test and MELN gene-reporter luciferase assay, respectively. There was a positive and significant correlation between the two tests (Rho S = 0.650, p = 0.022). This study indicates that the environmental risk is low because oestrogenic substances are deposited into the river via IWWTP at concentrations lower than those at which chronic exposure has been reported to affect the endocrine system of living organisms. -- Highlights: Black-Right-Pointing-Pointer The two in vitro tests are suited for oestrogenic activity assessment in textile WWTP. Black-Right-Pointing-Pointer There is a significant correlation between the results of the two in vitro tests. Black-Right-Pointing-Pointer The oestrogenic activity of the effluent is reduced by ozonation. Black-Right-Pointing-Pointer The input of estrogenic substances into the river via textile WWTP is low.

  5. WellReader: a MATLAB program for the analysis of fluorescence and luminescence reporter gene data.

    Science.gov (United States)

    Boyer, Frédéric; Besson, Bruno; Baptist, Guillaume; Izard, Jérôme; Pinel, Corinne; Ropers, Delphine; Geiselmann, Johannes; de Jong, Hidde

    2010-05-01

    Fluorescent and luminescent reporter gene systems in combination with automated microplate readers allow real-time monitoring of gene expression on the population level at high precision and sampling density. This generates large amounts of data for the analysis of which computer tools are missing to date. We have developed WellReader, a MATLAB program for the analysis of fluorescent and luminescent reporter gene data. WellReader allows the user to load the output files of microplate readers, remove outliers, correct for background effects and smooth and fit the data. Moreover, it computes biologically relevant quantities from the measured signals, notably promoter activities and protein concentrations, and compares the resulting expression profiles of different genes under different conditions. WellReader is available under a LGPL licence at http://prabi1.inrialpes.fr/trac/wellreader.

  6. High-Throughput Screening of a Luciferase Reporter of Gene Silencing on the Inactive X Chromosome.

    Science.gov (United States)

    Keegan, Alissa; Plath, Kathrin; Damoiseaux, Robert

    2018-01-01

    Assays of luciferase gene activity are a sensitive and quantitative reporter system suited to high-throughput screening. We adapted a luciferase assay to a screening strategy for identifying factors that reactivate epigenetically silenced genes. This epigenetic luciferase reporter is subject to endogenous gene silencing mechanisms on the inactive X chromosome (Xi) in primary mouse cells and thus captures the multilayered nature of chromatin silencing in development. Here, we describe the optimization of an Xi-linked luciferase reactivation assay in 384-well format and adaptation of the assay for high-throughput siRNA and chemical screening. Xi-luciferase reactivation screening has applications in stem cell biology and cancer therapy. We have used the approach described here to identify chromatin-modifying proteins and to identify drug combinations that enhance the gene reactivation activity of the DNA demethylating drug 5-aza-2'-deoxycytidine.

  7. Composites of malonic acid diamides and phospholipids--Impact of lipoplex stability on transfection efficiency.

    Science.gov (United States)

    Janich, Christopher; Wölk, Christian; Erdmann, Frank; Groth, Thomas; Brezesinski, Gerald; Dobner, Bodo; Langner, Andreas

    2015-12-28

    The use of cationic lipids as gene delivery systems is a basic method in gene therapy. Through ongoing research, lipofection is currently the leader of non-viral vectors in clinical trials. However, in order to unleash the full potential of lipofection further intensive investigations are indispensable. In this study, various lipoplex formulations were compared regarding their ability to bind DNA. To obtain information about a possible premature release of DNA at the cell surface, heparin and chondroitin dependent lipoplex destabilization experiments were carried out. Complementary investigations in cell culture were performed to quantify DNA outside the cell. Additionally, DNase I stability was investigated. In this regard a multitude of methods, namely confocal laser scanning microscopy (CLSM), polymerase chain reaction (PCR), cell culture experiments, ethidium bromide assay, gel electrophoresis, Langmuir-isotherm experiments, infrared reflection absorption spectroscopy (IRRAS), Brewster angle microscopy (BAM), zeta-(ζ)-potential measurements, and dynamic light scattering (DLS), were applied. Although the complexation of DNA is a fundamental step, we show that the DNA release by biological agents (proteoglycans) and an unsuccessful cell attachment are major transfection limiting parameters. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. A cell spot microarray method for production of high density siRNA transfection microarrays

    Directory of Open Access Journals (Sweden)

    Mpindi John-Patrick

    2011-03-01

    Full Text Available Abstract Background High-throughput RNAi screening is widely applied in biological research, but remains expensive, infrastructure-intensive and conversion of many assays to HTS applications in microplate format is not feasible. Results Here, we describe the optimization of a miniaturized cell spot microarray (CSMA method, which facilitates utilization of the transfection microarray technique for disparate RNAi analyses. To promote rapid adaptation of the method, the concept has been tested with a panel of 92 adherent cell types, including primary human cells. We demonstrate the method in the systematic screening of 492 GPCR coding genes for impact on growth and survival of cultured human prostate cancer cells. Conclusions The CSMA method facilitates reproducible preparation of highly parallel cell microarrays for large-scale gene knockdown analyses. This will be critical towards expanding the cell based functional genetic screens to include more RNAi constructs, allow combinatorial RNAi analyses, multi-parametric phenotypic readouts or comparative analysis of many different cell types.

  9. Alpha-fetoprotein-targeted reporter gene expression imaging in hepatocellular carcinoma.

    Science.gov (United States)

    Kim, Kwang Il; Chung, Hye Kyung; Park, Ju Hui; Lee, Yong Jin; Kang, Joo Hyun

    2016-07-21

    Hepatocellular carcinoma (HCC) is one of the most common cancers in Eastern Asia, and its incidence is increasing globally. Numerous experimental models have been developed to better our understanding of the pathogenic mechanism of HCC and to evaluate novel therapeutic approaches. Molecular imaging is a convenient and up-to-date biomedical tool that enables the visualization, characterization and quantification of biologic processes in a living subject. Molecular imaging based on reporter gene expression, in particular, can elucidate tumor-specific events or processes by acquiring images of a reporter gene's expression driven by tumor-specific enhancers/promoters. In this review, we discuss the advantages and disadvantages of various experimental HCC mouse models and we present in vivo images of tumor-specific reporter gene expression driven by an alpha-fetoprotein (AFP) enhancer/promoter system in a mouse model of HCC. The current mouse models of HCC development are established by xenograft, carcinogen induction and genetic engineering, representing the spectrum of tumor-inducing factors and tumor locations. The imaging analysis approach of reporter genes driven by AFP enhancer/promoter is presented for these different HCC mouse models. Such molecular imaging can provide longitudinal information about carcinogenesis and tumor progression. We expect that clinical application of AFP-targeted reporter gene expression imaging systems will be useful for the detection of AFP-expressing HCC tumors and screening of increased/decreased AFP levels due to disease or drug treatment.

  10. The first report of prion-related protein gene (PRNT) polymorphisms in goat.

    Science.gov (United States)

    Kim, Yong-Chan; Jeong, Byung-Hoon

    2017-06-01

    Prion protein is encoded by the prion protein gene (PRNP). Polymorphisms of several members of the prion gene family have shown association with prion diseases in several species. Recent studies on a novel member of the prion gene family in rams have shown that prion-related protein gene (PRNT) has a linkage with codon 26 of prion-like protein (PRND). In a previous study, codon 26 polymorphism of PRND has shown connection with PRNP haplotype which is strongly associated with scrapie vulnerability. In addition, the genotype of a single nucleotide polymorphism (SNP) at codon 26 of PRND is related to fertilisation capacity. These findings necessitate studies on the SNP of PRNT gene which is connected with PRND. In goat, several polymorphism studies have been performed for PRNP, PRND, and shadow of prion protein gene (SPRN). However, polymorphism on PRNT has not been reported. Hence, the objective of this study was to determine the genotype and allelic distribution of SNPs of PRNT in 238 Korean native goats and compare PRNT DNA sequences between Korean native goats and several ruminant species. A total of five SNPs, including PRNT c.-114G > T, PRNT c.-58A > G in the upstream of PRNT gene, PRNT c.71C > T (p.Ala24Val) and PRNT c.102G > A in the open reading frame (ORF) and c.321C > T in the downstream of PRNT gene, were found in this study. All five SNPs of caprine PRNT gene in Korean native goat are in complete linkage disequilibrium (LD) with a D' value of 1.0. Interestingly, comparative sequence analysis of the PRNT gene revealed five mismatches between DNA sequences of Korean native goats and those of goats deposited in the GenBank. Korean native black goats also showed 5 mismatches in PRNT ORF with cattle. To the best of our knowledge, this is the first genetic research of the PRNT gene in goat.

  11. Using reporter gene assays to identify cis regulatory differences between humans and chimpanzees.

    Science.gov (United States)

    Chabot, Adrien; Shrit, Ralla A; Blekhman, Ran; Gilad, Yoav

    2007-08-01

    Most phenotypic differences between human and chimpanzee are likely to result from differences in gene regulation, rather than changes to protein-coding regions. To date, however, only a handful of human-chimpanzee nucleotide differences leading to changes in gene regulation have been identified. To hone in on differences in regulatory elements between human and chimpanzee, we focused on 10 genes that were previously found to be differentially expressed between the two species. We then designed reporter gene assays for the putative human and chimpanzee promoters of the 10 genes. Of seven promoters that we found to be active in human liver cell lines, human and chimpanzee promoters had significantly different activity in four cases, three of which recapitulated the gene expression difference seen in the microarray experiment. For these three genes, we were therefore able to demonstrate that a change in cis influences expression differences between humans and chimpanzees. Moreover, using site-directed mutagenesis on one construct, the promoter for the DDA3 gene, we were able to identify three nucleotides that together lead to a cis regulatory difference between the species. High-throughput application of this approach can provide a map of regulatory element differences between humans and our close evolutionary relatives.

  12. Early Infantile Leigh-like Gene Defects Have a Poor Prognosis: Report and Review

    Directory of Open Access Journals (Sweden)

    Majid Alfadhel

    2017-10-01

    Full Text Available Solute carrier family 19 (thiamine transporter, member 3 ( SCL19A3 gene defect produces an autosomal recessive neurodegenerative disorder associated with different phenotypes and acronyms. One of the common presentations is early infantile lethal Leigh-like syndrome. We report a case of early infantile Leigh-like SLC19A3 gene defects of patients who died at 4 months of age with no response to a high dose of biotin and thiamine. In addition, we report a novel mutation that was not reported previously. Finally, we review the literature regarding early infantile Leigh-like SLC19A3 gene defects and compare the literature with our patient.

  13. Environmental Application of Reporter-Genes Based Biosensors for Chemical Contamination Screening

    Directory of Open Access Journals (Sweden)

    Matejczyk Marzena

    2014-12-01

    Full Text Available The paper presents results of research concerning possibilities of applications of reporter-genes based microorganisms, including the selective presentation of defects and advantages of different new scientific achievements of methodical solutions in genetic system constructions of biosensing elements for environmental research. The most robust and popular genetic fusion and new trends in reporter genes technology – such as LacZ (β-galactosidase, xylE (catechol 2,3-dioxygenase, gfp (green fluorescent proteins and its mutated forms, lux (prokaryotic luciferase, luc (eukaryotic luciferase, phoA (alkaline phosphatase, gusA and gurA (β-glucuronidase, antibiotics and heavy metals resistance are described. Reporter-genes based biosensors with use of genetically modified bacteria and yeast successfully work for genotoxicity, bioavailability and oxidative stress assessment for detection and monitoring of toxic compounds in drinking water and different environmental samples, surface water, soil, sediments.

  14. Differential polymer structure tunes mechanism of cellular uptake and transfection routes of poly(β-amino ester) polyplexes in human breast cancer cells.

    Science.gov (United States)

    Kim, Jayoung; Sunshine, Joel C; Green, Jordan J

    2014-01-15

    Successful gene delivery with nonviral particles has several barriers, including cellular uptake, endosomal escape, and nuclear transport. Understanding the mechanisms behind these steps is critical to enhancing the effectiveness of gene delivery. Polyplexes formed with poly(β-amino ester)s (PBAEs) have been shown to effectively transfer DNA to various cell types, but the mechanism of their cellular uptake has not been identified. This is the first study to evaluate the uptake mechanism of PBAE polyplexes and the dependence of cellular uptake on the end group and molecular weight of the polymer. We synthesized three different analogues of PBAEs with the same base polymer poly(1,4-butanediol diacrylate-co-4-amino-1-butanol) (B4S4) but with small changes in the end group or molecular weight. We quantified the uptake and transfection efficiencies of the pDNA polyplexes formulated from these polymers in hard-to-transfect triple negative human breast cancer cells (MDA-MB 231). All polymers formed positively charged (10-17 mV) nanoparticles of ∼200 nm in size. Cellular internalization of all three formulations was inhibited the most (60-90% decrease in cellular uptake) by blocking caveolae-mediated endocytosis. Greater inhibition was shown with polymers that had a 1-(3-aminopropyl)-4-methylpiperazine end group (E7) than the others with a 2-(3-aminopropylamino)-ethanol end group (E6) or higher molecular weight. However, caveolae-mediated endocytosis was generally not as efficient as clathrin-mediated endocytosis in leading to transfection. These findings indicate that PBAE polyplexes can be used to transfect triple negative human breast cancer cells and that small changes to the same base polymer can modulate their cellular uptake and transfection routes.

  15. Detection of anabolic androgenic steroid abuse in doping control using mammalian reporter gene bioassays.

    Science.gov (United States)

    Houtman, Corine J; Sterk, Saskia S; van de Heijning, Monique P M; Brouwer, Abraham; Stephany, Rainer W; van der Burg, Bart; Sonneveld, Edwin

    2009-04-01

    Anabolic androgenic steroids (AAS) are a class of steroid hormones related to the male hormone testosterone. They are frequently detected as drugs in sport doping control. Being similar to or derived from natural male hormones, AAS share the activation of the androgen receptor (AR) as common mechanism of action. The mammalian androgen responsive reporter gene assay (AR CALUX bioassay), measuring compounds interacting with the AR can be used for the analysis of AAS without the necessity of knowing their chemical structure beforehand, whereas current chemical-analytical approaches may have difficulty in detecting compounds with unknown structures, such as designer steroids. This study demonstrated that AAS prohibited in sports and potential designer AAS can be detected with this AR reporter gene assay, but that also additional steroid activities of AAS could be found using additional mammalian bioassays for other types of steroid hormones. Mixtures of AAS were found to behave additively in the AR reporter gene assay showing that it is possible to use this method for complex mixtures as are found in doping control samples, including mixtures that are a result of multi drug use. To test if mammalian reporter gene assays could be used for the detection of AAS in urine samples, background steroidal activities were measured. AAS-spiked urine samples, mimicking doping positive samples, showed significantly higher androgenic activities than unspiked samples. GC-MS analysis of endogenous androgens and AR reporter gene assay analysis of urine samples showed how a combined chemical-analytical and bioassay approach can be used to identify samples containing AAS. The results indicate that the AR reporter gene assay, in addition to chemical-analytical methods, can be a valuable tool for the analysis of AAS for doping control purposes.

  16. Transfection of small numbers of human endothelial cells by electroporation and synthetic amphiphiles

    NARCIS (Netherlands)

    van Leeuwen, E B; van der Veen, A Y; Hoekstra, D; Engberts, J B; Halie, M R; van der Meer, J; Ruiters, M H

    OBJECTIVES: This study compared the efficiency of electroporation and synthetic amphiphiles. (SAINT-2pp/DOPE) in transfecting small numbers of human endothelial cells. METHODS AND RESULTS: Optimal transfection conditions were tested and appeared to be 400 V and 960 microF for electroporation and a

  17. Targeted surface expression of an exogenous antigen in stably transfected babesia bovis

    Science.gov (United States)

    Babesia bovis is a tick-borne intraerythocytic protozoan responsible for acute disease in cattle which can be controlled by vaccination with attenuated B. bovis strains. Emerging B. bovis transfection technologies may increase the usefulness of these live vaccines. Here we propose using transfected ...

  18. Use of mariner transposases for one-step delivery and integration of DNA in prokaryotes and eukaryotes by transfection.

    Science.gov (United States)

    Trubitsyna, Maryia; Michlewski, Gracjan; Finnegan, David J; Elfick, Alistair; Rosser, Susan J; Richardson, Julia M; French, Christopher E

    2017-06-02

    Delivery of DNA to cells and its subsequent integration into the host genome is a fundamental task in molecular biology, biotechnology and gene therapy. Here we describe an IP-free one-step method that enables stable genome integration into either prokaryotic or eukaryotic cells. A synthetic mariner transposon is generated by flanking a DNA sequence with short inverted repeats. When purified recombinant Mos1 or Mboumar-9 transposase is co-transfected with transposon-containing plasmid DNA, it penetrates prokaryotic or eukaryotic cells and integrates the target DNA into the genome. In vivo integrations by purified transposase can be achieved by electroporation, chemical transfection or Lipofection of the transposase:DNA mixture, in contrast to other published transposon-based protocols which require electroporation or microinjection. As in other transposome systems, no helper plasmids are required since transposases are not expressed inside the host cells, thus leading to generation of stable cell lines. Since it does not require electroporation or microinjection, this tool has the potential to be applied for automated high-throughput creation of libraries of random integrants for purposes including gene knock-out libraries, screening for optimal integration positions or safe genome locations in different organisms, selection of the highest production of valuable compounds for biotechnology, and sequencing. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  19. Cationic lipid-mediated transfection in vitro and in vivo

    NARCIS (Netherlands)

    Audouy, S; Hoekstra, D

    2001-01-01

    Recent rapid developments in genomics will likely lead to a rapid expansion in identifying defective genes causing a variety of diseases, implying a vast increase in the number of therapeutic targets. Treatment of such diseases may include strategies ranging from gene delivery and replacement to

  20. Role of cholesterol on the transfection barriers of cationic lipid/DNA complexes

    Science.gov (United States)

    Pozzi, Daniela; Cardarelli, Francesco; Salomone, Fabrizio; Marchini, Cristina; Amenitsch, Heinz; Barbera, Giorgia La; Caracciolo, Giulio

    2014-08-01

    Most lipid formulations need cholesterol for efficient transfection, but the precise motivation remains unclear. Here, we have investigated the effect of cholesterol on the transfection efficiency (TE) of cationic liposomes made of 1,2-dioleoyl-3-trimethylammonium-propane and dioleoylphosphocholine in Chinese hamster ovary cells. The transfection mechanisms of cholesterol-containing lipoplexes have been investigated by TE, synchrotron small angle X-ray scattering, and laser scanning confocal microscopy experiments. We prove that cholesterol-containing lipoplexes enter the cells using different endocytosis pathways. Formulations with high cholesterol content efficiently escape from endosomes and exhibit a lamellar-nonlamellar phase transition in mixture with biomembrane mimicking lipid formulations. This might explain both the DNA release ability and the high transfection efficiency. These studies highlight the enrichment in cholesterol as a decisive factor for transfection and will contribute to the rational design of lipid nanocarriers with superior TE.

  1. The sustained-release behavior and in vitro and in vivo transfection of pEGFP-loaded core-shell-structured chitosan-based composite particles

    Directory of Open Access Journals (Sweden)

    Wang Y

    2014-10-01

    Full Text Available Yun Wang,1 Fu-xing Lin,2 Yu Zhao,1 Mo-zhen Wang,2 Xue-wu Ge,2 Zheng-xing Gong,1 Dan-dan Bao,1 Yu-fang Gu1 1Department of Plastic Surgery, First Affiliated Hospital of Anhui Medical University, 2CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China Abstract: Novel submicron core-shell-structured chitosan-based composite particles ­encapsulated with enhanced green fluorescent protein plasmids (pEGFP were prepared by complex coacervation method. The core was pEGFP-loaded thiolated N-alkylated chitosan (TACS and the shell was pH- and temperature-responsive hydroxybutyl chitosan (HBC. pEGFP-loaded TACS-HBC composite particles were spherical, and had a mean diameter of approximately 120 nm, as measured by transmission electron microscopy and particle size analyzer. pEGFP showed sustained release in vitro for >15 days. Furthermore, in vitro transfection in human embryonic kidney 293T and human cervix epithelial cells, and in vivo transfection in mice skeletal muscle of loaded pEGFP, were investigated. Results showed that the expression of loaded pEGFP, both in vitro and in vivo, was slow but could be sustained over a long period. pEGFP expression in mice skeletal muscle was sustained for >60 days. This work indicates that these submicron core-shell-structured chitosan-based composite particles could potentially be used as a gene vector for in vivo controlled gene transfection. Keywords: gene therapy, gene transfection, hydroxybutyl chitosan, thiolated N-alkylated chitosan, pEGFP, complex coacervation

  2. Expression of intracellular interferon-alpha confers antiviral properties in transfected bovine fetal fibroblasts and does not affect the full development of SCNT embryos.

    Directory of Open Access Journals (Sweden)

    Dawei Yu

    Full Text Available Foot-and-mouth disease, one of the most significant diseases of dairy herds, has substantial effects on farm economics, and currently, disease control measures are limited. In this study, we constructed a vector with a human interferon-α (hIFN-α (without secretory signal sequence gene cassette containing the immediate early promoter of human cytomegalovirus. Stably transfected bovine fetal fibroblasts were obtained by G418 selection, and hIFN-α transgenic embryos were produced by somatic cell nuclear transfer (SCNT. Forty-six transgenic embryos were transplanted into surrogate cows, and five cows (10.9% became pregnant. Two male cloned calves were born. Expression of hIFN-α was detected in transfected bovine fetal fibroblasts, transgenic SCNT embryos, and different tissues from a transgenic SCNT calf at two days old. In transfected bovine fetal fibroblasts, expression of intracellular IFN-α induced resistance to vesicular stomatitis virus infection, increased apoptosis, and induced the expression of double-stranded RNA-activated protein kinase gene (PKR and the 2'-5'-oligoadenylate synthetase gene (2'-5' OAS, which are IFN-inducible genes with antiviral activity. Analysis by qRT-PCR showed that the mRNA expression levels of PKR, 2'-5' OAS, and P53 were significantly increased in wild-type bovine fetal fibroblasts stimulated with extracellular recombinant human IFN-α-2b, showing that intracellular IFN-α induces biological functions similar to extracellular IFN-α. In conclusion, expression of intracellular hIFN-α conferred antiviral properties in transfected bovine fetal fibroblasts and did not significantly affect the full development of SCNT embryos. Thus, IFN-α transgenic technology may provide a revolutionary way to achieve elite breeding of livestock.

  3. Construction of a CD147 Lentiviral Expression Vector and Establishment of Its Stably Transfected A549 Cell Line

    Directory of Open Access Journals (Sweden)

    Shaoxing YANG

    2012-12-01

    Full Text Available Background and objective CD147, a type of transmembrane glycoprotein embedded on the surface of tumor cells, can promote tumor invasion and metastasis. This aim of this study is to construct a CD147 lentiviral expression vector, establish its stably transfected A549 cell line, and observe the effect of CD147 on MMP-9 proliferation as well as on the invasive ability of human lung adenocarcinoma cells. Methods Full-length CD147 gene was amplified by real-time polymerase chain reaction (RT-PCR, inserted into a pEGFP vector to construct pEGFP-CD147 and pEGFP vectors, and then transfected into 293FT cells to precede the lentivirus equipment package. Subsequently, we collected the lentivirus venom to infect the A549 cells and establish a stable, overexpressed cell line named A549-CD147. The mRNA expression of MMP-9 was examined by RT-PCR. The proliferation and invasive ability of the human lung cancer cells before and after transfection were examined by the CCK-8 and Transwell methods. Results A CD147 lentiviral expression vector (pEGFP-CD147 was successfully constructed by restrictive enzyme digestion and plasmid sequencing. RT-PCR and Western blot analyses revealed increased mRNA and protein expression of CD147 gene in cells transfected with pEGFP-CD147 compared with the control groups. Therefore, the A549-CD147 cell line was successfully established through the experiment. The mRNA expression of MMP-9 also significantly increased after the upregulation of CD147 expression. Meanwhile, CCK-8 and Transwell assays indicated that the proliferation and invasive ability significantly increased in the A549-CD147 cells. Conclusion A lentiviral CD147 expression vector and its A549 cell line (A549-CD14 were successfully constructed. CD147 overexpression upregulated the protein expression of MMP-9, and strengthened the proliferation and invasive ability of human lung adenocarcinoma cells.

  4. Identification and Functional Analysis of Gene Regulatory Sequences Interacting with Colorectal Tumor Suppressors

    DEFF Research Database (Denmark)

    Dahlgaard, Katja; Troelsen, Jesper

    2018-01-01

    Several tumor suppressors possess gene regulatory activity. Here, we describe how promoter and promoter/enhancer reporter assays can be used to characterize a colorectal tumor suppressor proteins’ gene regulatory activity of possible target genes. In the first part, a bioinformatic approach...... of the quick and efficient In-Fusion cloning method, and how to carry out transient transfections of Caco-2 colon cancer cells with the produced luciferase reporter plasmids using polyethyleneimine (PEI). A plan describing how to set up and carry out the luciferase expression assay is presented. The luciferase...... to identify relevant gene regulatory regions of potential target genes is presented. In the second part, it is demonstrated how to prepare and carry out the functional assay. We explain how to clone the bioinformatically identified gene regulatory regions into luciferase reporter plasmids by the use...

  5. Reducible cationic lipids for gene transfer.

    Science.gov (United States)

    Wetzer, B; Byk, G; Frederic, M; Airiau, M; Blanche, F; Pitard, B; Scherman, D

    2001-01-01

    One of the main challenges of gene therapy remains the increase of gene delivery into eukaryotic cells. We tested whether intracellular DNA release, an essential step for gene transfer, could be facilitated by using reducible cationic DNA-delivery vectors. For this purpose, plasmid DNA was complexed with cationic lipids bearing a disulphide bond. This reduction-sensitive linker is expected to be reduced and cleaved in the reducing milieu of the cytoplasm, thus potentially improving DNA release and consequently transfection. The DNA--disulphide-lipid complexation was monitored by ethidium bromide exclusion, and the size of complexes was determined by dynamic light scattering. It was found that the reduction kinetics of disulphide groups in DNA--lipid complexes depended on the position of the disulphide linker within the lipid molecule. Furthermore, the internal structure of DNA--lipid particles was examined by small-angle X-ray scattering before and after lipid reduction. DNA release from lipid complexes was observed after the reduction of disulphide bonds of several lipids. Cell-transfection experiments suggested that complexes formed with selected reducible lipids resulted in up to 1000-fold higher reporter-gene activity, when compared with their analogues without disulphide bonds. In conclusion, reduction-sensitive groups introduced into cationic lipid backbones potentially allow enhanced DNA release from DNA--lipid complexes after intracellular reduction and represent a tool for improved vectorization. PMID:11389682

  6. Improved transfection of HUVEC and MEF cells using DNA ...

    Indian Academy of Sciences (India)

    in stem cell research and endothelial cell physiology and pathology studies are ... gene delivery technique, which uses magnetic nanoparticles under the influence of an ..... The generation of iPS cells using non-viral magnetic nanoparticle.

  7. Detection of estrogenic activity in sediment-associated compounds using in vitro reporter gene assays

    NARCIS (Netherlands)

    Legler, J.; Dennekamp, M.; Vethaak, A.D.; Brouwer, A.; Koeman, J.H.; Burg, van der B.; Murk, A.J.

    2002-01-01

    Sediments may be the ultimate sink for persistent (xeno-) estrogenic compounds released into the aquatic environment. Sediment-associated estrogenic potency was measured with an estrogen receptor-mediated luciferase reporter gene (ER-CALUX) assay and compared with a recombinant yeast screen. The

  8. New in vitro reporter gene bioassays for screening of hormonal active compounds in the environment

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Kateřina; Cajthaml, Tomáš

    2010-01-01

    Roč. 88, č. 4 (2010), s. 839-847 ISSN 0175-7598 R&D Projects: GA ČR GAP503/10/0408 Institutional research plan: CEZ:AV0Z50200510 Keywords : endocrine disruptors * in vitro bioassays * reporter gene assays Subject RIV: EE - Microbiology, Virology Impact factor: 3.280, year: 2010

  9. A case report on ATP6V0A4 gene mutation: Forecast of familial ...

    African Journals Online (AJOL)

    The patient does not have hearing impairment. ATP6V0A4 gene ... This case report emphasizes the significance of early diagnosis and genetic screening of recessive forms of ... Buffer defect /low buffer type distal RTA also involves the loss of ... weight of 4 Kg with no emergency treatment at the time of birth. Afterwards, his ...

  10. Expression of bovine herpesvirus 1 glycoproteins gI and gIII in transfected murine cells

    International Nuclear Information System (INIS)

    Fitzpatrick, D.R.; Zamb, T.; Parker, M.D.; van Drunen Littel-van den Hurk, S.; Babiuk, L.A.; Lawman, M.J.P.

    1988-01-01

    Genes encoding two of the major glycoproteins of bovine herpesvirus 1 (BHV-1), gI and gIII, were cloned into the eucaryotic expression vectors pRSVcat and pSV2neo and transfected into murine LMTK - cells, and cloned cell lines were established. The relative amounts of gI or gIII expressed from the two vectors were similar. Expression of gI was cell associated and localized predominantly in the perinuclear region, but nuclear and plasma membrane staining was also observed. Expression of gI was additionally associated with cell fusion and the formation of polykaryons and giant cells. Expression of gIII was localized predominantly in the nuclear and plasma membranes. Radioimmunoprecipitation in the presence or absence of tunicamycin revealed that the recombinant glycoproteins were proteolytically processed and glycosylated and had molecular weights similar to those of the forms of gI and gIII expressed in BHV-1 infected bovine cells. However, both recombinant glycoproteins were glycosylated to a lesser extent than were the forms found in BHV-1 infected bovine cells. For gI, a deficiency in N-linked glycosylated of the amino-terminal half of the protein was identified; for gIII, a deficiency in O-linked glycosylation was implicated. The reactivity pattern of a panel of gI- and gIII-specific monoclonal antibodies, including six which recognize conformation-dependent epitopes, was found to be unaffected by the glycosylation differences and was identical for transfected of BHV-1-infected murine cells. Use of the transfected cells as targets in immune-mediated cytotoxicity assays demonstrated the functional recognition of recombinant gI and gIII by murine antibody and cytotoxic T lymphocytes

  11. Stable transfection of Eimeria intestinalis and investigation of its life cycle, reproduction and immunogenicity

    Directory of Open Access Journals (Sweden)

    Tuanyuan eShi

    2016-05-01

    Full Text Available Rabbit coccidiosis, caused by infection of Eimeria spp. is one of the most severe parasitic diseases in rabbits. E. intestinalis is one of the most immunogenic species in rabbit coccidia. Due to the lack of genomic information and unsuccessful in vitro cultivation, genetic manipulation of rabbit coccidia lagged behind other apicomplexan parasites. Using regulatory sequences from E. tenella, we obtained a transgenic line of E. intestinalis expressing yellow fluorescent protein (YFP. YFP was continuously expressed throughout the whole life cycle. Morphological features of E. intestinalis in the different developmental stages were dynamically observed with the transgenic line. Some important features in the endogenous development stages were observed. Trophozoites were found as early as 4 h post inoculation. Two-types of schizonts and merozoites were observed in first three of the four schizogonies. Beside jejunum and ileum, gametogony stage and oocysts were also found in the duodenum and vermiform appendix. In addition, the transgenic strain was highly immunogenic but less pathogenic than the wild type. Considering the high immunogenicity of E. intestinalis and amenability to transfection with foreign genes, transgenic E. intestinalis could be a promising oral eukaryotic vaccine vector.

  12. Exploration of new perspectives and limitations in Agrobacterium mediated gene transfer technology. Progress report, [June 1, 1992-- May 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Marton, L.

    1994-12-31

    This report describes progress aimed at constructing gene-transfer technology for Nicotiana plumbaginifolia. Most actual effort as described herein has so far been directed at exploring new perspectives and limitations in Agrobacterium mediated gene transfer. Accomplishments are described using a core homologous gene targeting vector.

  13. Gene

    Data.gov (United States)

    U.S. Department of Health & Human Services — Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes,...

  14. Development of a calcium phosphate co-precipitate/poly(lactide-co-glycolide) DNA delivery system: release kinetics and cellular transfection studies.

    Science.gov (United States)

    Kofron, Michelle D; Laurencin, Cato T

    2004-06-01

    One of the most common non-viral methods for the introduction of foreign deoxyribonucleic acid (DNA) into cultured cells is calcium phosphate co-precipitate transfection. This technique involves the encapsulation of DNA within a calcium phosphate co-precipitate, particulate addition to in vitro cell culture, endocytosis of the co-precipitate, and exogenous DNA expression by the transfected cell. In this study, we fabricated a novel non-viral gene transfer system by adsorbing DNA, encapsulated in calcium phosphate (DNA/Ca-P) co-precipitates, to biodegradable two- and three-dimensional poly(lactide-co-glycolide) matrices (2D-DNA/Ca-P/PLAGA, 3D-DNA/Ca-P/PLAGA). Co-precipitate release studies demonstrated an initial burst release over the first 48 h. By day 7, approximately 96% of the initially adsorbed DNA/Ca-P co-precipitate had been released. This was followed by low levels of co-precipitate release for 42 days. Polymerase chain reaction was used to demonstrate the ability of the released DNA containing co-precipitates to transfect SaOS-2 cells cultured in vitro on the 3D-DNA/Ca-P/PLAGA matrix and maintenance of the structural integrity of the exogenous DNA. In summary, a promising system for the incorporation and controlled delivery of exogenous genes encapsulated within a calcium phosphate co-precipitate from biodegradable polymeric matrices has been developed and may have applicability to the delivery of therapeutic genes and the transfection of other cell types.

  15. Transfection efficiency and uptake process of polyplexes in human lung endothelial cells: a comparative study in non-polarized and polarized cells.

    Science.gov (United States)

    Mennesson, Eric; Erbacher, Patrick; Piller, Véronique; Kieda, Claudine; Midoux, Patrick; Pichon, Chantal

    2005-06-01

    Following systemic administration, polyplexes must cross the endothelium barrier to deliver genes to the target cells underneath. To design an efficient gene delivery system into lung epithelium, we evaluated capture and transfection efficiencies of DNA complexed with either Jet-PEI (PEI-polyplexes) or histidylated polylysine (His-polyplexes) in human lung microvascular endothelial cells (HLMEC) and tracheal epithelial cells. After optimizing growth conditions to obtain a tight HLMEC monolayer, we characterized uptake of polyplexes by flow cytometry and evaluated their transfection efficiency. Polyplexes were formulated as small particles. YOYO-labelled plasmid fluorescence intensity and luciferase activity were used as readouts for uptake and gene expression, respectively. PEI-polyplexes were more efficiently taken up than His-polyplexes by both non-polarized (2-fold) and polarized HLMEC (10-fold). They were mainly internalized by a clathrin-dependent pathway whatever the cell state. In non-polarized cells, His-polyplexes entered also mainly via a clathrin-dependent pathway but with an involvement of cholesterol. The cell polarization decreased this way and a clathrin-independent pathway became predominant. PEI-polyplexes transfected more efficiently HLMEC than His-polyplexes (10(7) vs. 10(5) relative light units (RLU)/mg of proteins) with a more pronounced difference in polarized cells. In contrast, no negative effect of the cell polarization was observed with tracheal epithelial cells in which both polyplexes had comparable efficiency. We show that the efficiency of polyplex uptake by HLMEC and their internalization mechanism are polymer-dependent. By contrast with His-polyplexes, the HLMEC polarization has little influence on the uptake process and on the transfection efficiency of PEI-polyplexes. Copyright (c) 2005 John Wiley & Sons, Ltd.

  16. Peptide Dendrimer/Lipid Hybrid Systems Are Efficient DNA Transfection Reagents: Structure–Activity Relationships Highlight the Role of Charge Distribution Across Dendrimer Generations

    Science.gov (United States)

    2013-01-01

    Efficient DNA delivery into cells is the prerequisite of the genetic manipulation of organisms in molecular and cellular biology as well as, ultimately, in nonviral gene therapy. Current reagents, however, are relatively inefficient, and structure–activity relationships to guide their improvement are hard to come by. We now explore peptide dendrimers as a new type of transfection reagent and provide a quantitative framework for their evaluation. A collection of dendrimers with cationic and hydrophobic amino acid motifs (such as KK, KA, KH, KL, and LL) distributed across three dendrimer generations was synthesized by a solid-phase protocol that provides ready access to dendrimers in milligram quantities. In conjunction with a lipid component (DOTMA/DOPE), the best reagent, G1,2,3-KL ((LysLeu)8(LysLysLeu)4(LysLysLeu)2LysGlySerCys-NH2), improves transfection by 6–10-fold over commercial reagents under their respective optimal conditions. Emerging structure–activity relationships show that dendrimers with cationic and hydrophobic residues distributed in each generation are transfecting most efficiently. The trigenerational dendritic structure has an advantage over a linear analogue worth up to an order of magnitude. The success of placing the decisive cationic charge patterns in inner shells rather than previously on the surface of macromolecules suggests that this class of dendrimers significantly differs from existing transfection reagents. In the future, this platform may be tuned further and coupled to cell-targeting moieties to enhance transfection and cell specificity. PMID:23682947

  17. Complementation of radiation-sensitive Ataxia telangiectasia cells after transfection of cDNA expression libraries and cosmid clones from wildtype cells

    International Nuclear Information System (INIS)

    Fritz, E.

    1994-06-01

    In this Ph.D.-thesis, phenotypic complementation of AT-cells (AT5BIVA) by transfection of cDNA-expression-libraries was adressed: After stable transfection of cDNA-expression-libraries G418 resistant clones were selected for enhanced radioresistance by a fractionated X-ray selection. One surviving transfectant clone (clone 514) exhibited enhanced radiation resistance in dose-response experiments and further X-ray selections. Cell cycle analysis revealed complementation of untreated and irradiated 514-cells in cell cycle progression. The rate of DNA synthesis, however, is not diminished after irradiation but shows the reverse effect. A transfected cDNA-fragment (AT500-cDNA) was isolated from the genomic DNA of 514-cells and proved to be an unknown DNA sequence. A homologous sequence could be detected in genomic DNA from human cell lines, but not in DNA from other species. The cDNA-sequence could be localized to human chromosome 11. In human cells the cDNA sequence is part of two large mRNAs. 4 different cosmid clones containing high molecular genomic DNA from normal human cells could be isolated from a library, each hybridizing to the AT500-cDNA. After stable transfection into AT-cells, one cosmid-clone was able to confer enhanced radiation resistance both in X-ray selections and dose-response experiments. The results indicate that the cloned cDNA-fragment is based on an unknown gene from human chromosome 11 which partially complements the radiosensitivity and the defective cell cycle progression in AT5BIVA cells. (orig.) [de

  18. Splicing defect in FKBP10 gene causes autosomal recessive osteogenesis imperfecta disease: a case report.

    Science.gov (United States)

    Maghami, Fatemeh; Tabei, Seyed Mohammad Bagher; Moravej, Hossein; Dastsooz, Hassan; Modarresi, Farzaneh; Silawi, Mohammad; Faghihi, Mohammad Ali

    2018-05-25

    Osteogenesis imperfecta (OI) is a group of connective tissue disorder caused by mutations of genes involved in the production of collagen and its supporting proteins. Although the majority of reported OI variants are in COL1A1 and COL1A2 genes, recent reports have shown problems in other non-collagenous genes involved in the post translational modifications, folding and transport, transcription and proliferation of osteoblasts, bone mineralization, and cell signaling. Up to now, 17 types of OI have been reported in which types I to IV are the most frequent cases with autosomal dominant pattern of inheritance. Here we report an 8- year- old boy with OI who has had multiple fractures since birth and now he is wheelchair-dependent. To identify genetic cause of OI in our patient, whole exome sequencing (WES) was carried out and it revealed a novel deleterious homozygote splice acceptor site mutation (c.1257-2A > G, IVS7-2A > G) in FKBP10 gene in the patient. Then, the identified mutation was confirmed using Sanger sequencing in the proband as homozygous and in his parents as heterozygous, indicating its autosomal recessive pattern of inheritance. In addition, we performed RT-PCR on RNA transcripts originated from skin fibroblast of the proband to analyze the functional effect of the mutation on splicing pattern of FKBP10 gene and it showed skipping of the exon 8 of this gene. Moreover, Real-Time PCR was carried out to quantify the expression level of FKBP10 in the proband and his family members in which it revealed nearly the full decrease in the level of FKBP10 expression in the proband and around 75% decrease in its level in the carriers of the mutation, strongly suggesting the pathogenicity of the mutation. Our study identified, for the first time, a private pathogenic splice site mutation in FKBP10 gene and further prove the involvement of this gene in the rare cases of autosomal recessive OI type XI with distinguished clinical