scholarly journals Poly-L-ornithine-mediated transformation of mammalian cells.

1987 ◽  
Vol 7 (6) ◽  
pp. 2286-2293 ◽  
Author(s):  
V C Bond ◽  
B Wold
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
High Efficiency ◽  
Protein Product ◽  
Marker Genes ◽  
Recipient Mouse ◽  
L Cells ◽  
Dna And Rna ◽  
Selectable Marker Genes

Poly-L-ornithine has been used to introduce DNA and RNA into mammalian cells in culture. Ornithine-mediated DNA transfer has several interesting and potentially useful properties. The procedure is technically straightforward and is easily applied to either small or large numbers of recipient cells. The efficiency of transformation is high. Under optimal conditions, 1 to 2% of recipient mouse L cells take up and continue to express selectable marker genes. DNA content of transformants can be varied reproducibly, yielding cells with just one or two copies of the new gene under one set of conditions, while under a different set of conditions 25 to 50 copies are acquired. Cotransformation and expression of physically unlinked genes occur at high efficiency under conditions favoring multiple-copy transfer. Polyornithine promotes gene transfer into cell lines other than L cells. These include Friend erythroleukemia cells and NIH 3T3 cells. Both are transformed about 1 order of magnitude more efficiently by this procedure than by standard calcium phosphate products. However, the method does not abolish the large transformation efficiency differences between these cell lines that have been observed previously by other techniques. (vi) mRNA synthesized in vitro was also introduced into cells by this method. The RNA was translated resulting in a transient accumulation of the protein product.

scholarly journals Poly-L-ornithine-mediated transformation of mammalian cells

1987 ◽  
Vol 7 (6) ◽  
pp. 2286-2293
Author(s):  
V C Bond ◽  
B Wold
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
High Efficiency ◽  
Protein Product ◽  
Marker Genes ◽  
Recipient Mouse ◽  
L Cells ◽  
Dna And Rna ◽  
Selectable Marker Genes

Poly-L-ornithine has been used to introduce DNA and RNA into mammalian cells in culture. Ornithine-mediated DNA transfer has several interesting and potentially useful properties. The procedure is technically straightforward and is easily applied to either small or large numbers of recipient cells. The efficiency of transformation is high. Under optimal conditions, 1 to 2% of recipient mouse L cells take up and continue to express selectable marker genes. DNA content of transformants can be varied reproducibly, yielding cells with just one or two copies of the new gene under one set of conditions, while under a different set of conditions 25 to 50 copies are acquired. Cotransformation and expression of physically unlinked genes occur at high efficiency under conditions favoring multiple-copy transfer. Polyornithine promotes gene transfer into cell lines other than L cells. These include Friend erythroleukemia cells and NIH 3T3 cells. Both are transformed about 1 order of magnitude more efficiently by this procedure than by standard calcium phosphate products. However, the method does not abolish the large transformation efficiency differences between these cell lines that have been observed previously by other techniques. (vi) mRNA synthesized in vitro was also introduced into cells by this method. The RNA was translated resulting in a transient accumulation of the protein product.

scholarly journals RPNs Levels are Prognostic and Diagnostic Markers for Hepatocellular Carcinoma

2021 ◽  
Author(s):  
Wangyang zheng ◽  
Yuling Zheng ◽  
Xue Bai ◽  
Yongxu Zhou ◽  
Liang Yu ◽  
...  
Keyword(s):  
Western Blot ◽  
Cell Lines ◽  
Mammalian Cells ◽  
Tumor Grade ◽  
Ubiquitin Proteasome System ◽  
Functional Enrichment ◽  
Migration And Invasion ◽  
Regulatory Subunits ◽  
Hcc Cells

Abstract Background: Ribophorin family (RPNs) are important regulatory subunits of the proteasome. By influencing Ubiquitin-proteasome system activity, RPNs are responsible for almost all processes of physiology and pathology of mammalian cells. Nevertheless, little is known about the role of RPNs in HCC.Methods: In this work, using the online databases Oncomine, UCSC, Kaplan-Meier Plotter, UALCAN, cBioPortal, TIMER2, GeneMANIA,and STRING, we first evaluated the expression, diagnostic, prognostic, genetic alteration, immunity, gene network, and functional enrichment of RPNs in HCC. QPCR and western blot were used to detect RPN6 and RPN9 expressions in HCC tissues and cell lines. Then we performed studies to eveulated their functions in HCC cells proliferation, migration, and invasion in vitro. Results: All RPNs were surprisingly consistently upregulated in HCC tissues. Moreover, RPNs expression pattern is correlated with HCC tumor grade. RPN2, RPN3, RPN6, RPN9, RPN10, RPN11, and RPN12 have robust values in HCC diagnose. Then, survival analysis revealed that high expression of RPN1, RPN2, RPN4, RPN5, RPN6, RPN9, and RPN11were correlated with unfavorable HCC overall survival. Functional enrichment for RPNs, indicated that RPNs have many potential biosynthesis activities expert for UPS functions. Western blot, and qRT-PCR further verified these results in HCC tissues and cell lines. The silencing of RPN6 and RPN9 significantly influenced HCC cells' proliferation, migration, and invasion in vitro.Conclusions: RPN families functions as an important oncogene in HCC. RPN6 and RPN9 have the potential to be potential biomarkers and targets for HCC.

scholarly journals Development and Application of TK6-derived Cells Expressing Human Cytochrome P450s for Genotoxicity Testing

2020 ◽  
Vol 175 (2) ◽  
pp. 251-265 ◽  
Author(s):  
Xilin Li ◽  
Si Chen ◽  
Xiaoqing Guo ◽  
Qiangen Wu ◽  
Ji-Eun Seo ◽  
...  
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
Expression System ◽  
Cytochrome P450s ◽  
Mass Spectrometry Analysis ◽  
Established Cell Line ◽  
Micronucleus Formation ◽  
Tk6 Cells ◽  
Genotoxicity Testing

Abstract Metabolism plays a key role in chemical genotoxicity; however, most mammalian cells used for in vitro genotoxicity testing lack effective metabolizing enzymes. We recently developed a battery of TK6-derived cell lines that individually overexpress 1 of 8 cytochrome P450s (CYP1A1, 1A2, 1B1, 2A6, 2B6, 2C9, 2C19, and 3A4) using a lentiviral expression system. The increased expression and metabolic function of each individual CYP in each established cell line were confirmed using real-time PCR, Western blotting, and mass spectrometry analysis; the parental TK6 cells and empty vector (EV) transduced cells had negligible CYP levels. Subsequently, we evaluated these cell lines using 2 prototypical polyaromatic hydrocarbon mutagens, 7,12-dimethylbenz[a]anthracene (DMBA) and benzo[a]pyrene (B[a]P), that require metabolic activation to exert their genotoxicity. DMBA-induced cytotoxicity, phosphorylation of histone H2A.X, and micronucleus formation were significantly increased in TK6 cells with CYP1A1, 1B1, 2B6, and 2C19 expression as compared with EV controls. B[a]P significantly increased cytotoxicity, DNA damage, and chromosomal damage in TK6 cells overexpressing CYP1A1 and 1B1 when compared with EV controls. B[a]P also induced micronucleus formation in TK6 cells expressing CYP1A2. These results suggest that our CYP-expressing TK6 cell system can be used to detect the genotoxicity of compounds requiring metabolic transformation.

The Design and Synthesis of Novel Phenothiazine Derivatives as Potential Cytotoxic Agents

2019 ◽  
Vol 17 (1) ◽  
pp. 57-67
Author(s):  
Yepeng Luan ◽  
Jinyi Liu ◽  
Jianjun Gao ◽  
Jinhua Wang
Keyword(s):  
Cell Lines ◽  
High Efficiency ◽  
Human Cancer ◽  
Human Tumor ◽  
Cytotoxic Agents ◽  
Cancer Drug ◽  
Human Cancer Cell Lines ◽  
Incidence And Mortality ◽  
Anti Cancer

Background: Cancer incidence and mortality have been increasing and cancer is still the leading cause of death all over the world. Despite the enormous progress in cancer treatment, many patients died of ineffective chemotherapy and drug resistance. Therefore, the design and development of anti-cancer drugs with high efficiency and low toxicity is still one of the most challenging tasks. Tricyclic heterocycles, such as phenothiazine, are always important sources of scaffolds for anti-cancer drug discovery. Methods: In this work, ten new urea-containing derivatives of phenothiazine coupled with different kinds of amine motifs at the endpoint through a three carbon long spacer were designed and synthesized. The structures of the synthesized compounds were elucidated and confirmed by 1H NMR and HRMS. All the synthesized compounds were tested for their antitumor activity in vitro against the proliferation of PC-3 cells, and the compounds with best potency entered further cytotoxicity evaluations against other 22 human tumor cell lines. Mechanism was also studied. Results: From all data, it showed that among all 10 target compounds, TTi-2 showed the best effect in inhibiting the proliferation of 23 human cancer cell lines while TTi-2 without obvious inhibitory effect on normal cell. Furthermore, our results also showed that TTi-2 could inhibit migration, invasion and colony formation of MDA-MB-231 cells. Finally, TTi-2 can induce arrest of cell cycle at G0/G1 phase and cell apoptosis by activating the caspase 3 activity. Conclusion: All these results suggested that TTi-2 might be used as a promising lead compound for anticancer drug development.

scholarly journals Syncytin 1 dependent horizontal transfer of marker genes from retrovirally transduced cells

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Berna Uygur ◽  
Kamran Melikov ◽  
Anush Arakelyan ◽  
Leonid B. Margolis ◽  
Leonid V. Chernomordik
Keyword(s):  
Cell Lines ◽  
Membrane Vesicles ◽  
Retroviral Vectors ◽  
Extracellular Vesicle ◽  
Marker Genes ◽  
Target Cells ◽  
Retroviral Transduction ◽  
Gfp Gene ◽  
Safety Test

AbstractRetroviral transduction is routinely used to generate cell lines expressing exogenous non-viral genes. Here, we show that human cells transduced to stably express GFP transfer GFP gene to non-transduced cells. This horizontal gene transfer was mediated by a fraction of extracellular membrane vesicles that were released by the transduced cells. These vesicles carried endogenous retroviral envelope protein syncytin 1 and essentially acted as replication-competent retroviruses. The ability to transfer the GFP gene correlated with the levels of syncytin 1 expression in the transduced cells and depended on the fusogenic activity of this protein, substantiating the hypothesis that endogenous syncytin 1 mediates fusion stage in the delivery of extracellular vesicle cargo into target cells. Our findings suggest that testing for replication-competent retroviruses, a routine safety test for transduced cell products in clinical studies, should be also carried out for cell lines generated by retroviral vectors in in vitro studies.

Attachment of Salmonella to mammalian cells in vitro

1983 ◽  
Vol 29 (12) ◽  
pp. 1731-1735 ◽  
Author(s):  
Clifford S. Mintz ◽  
Dean O. Cliver ◽  
R. H. Deibel
Keyword(s):  
Cell Lines ◽  
Mammalian Cells ◽  
Culture Cell ◽  
Intestinal Cell ◽  
Tissue Culture Cell ◽  
Bacterial Cells ◽  
Intestinal Cell Line ◽  
Hela Cell Lines ◽  
High Concentrations

The attachment of Salmonella typhimurium strain PHL67342 to several mammalian tissue culture cell lines was investigated. Strain PHL67342 failed to attach in significant numbers to the Buffalo green monkey (BGM), swine testicular (ST), and HeLa cell lines. Significant attachment was observed with the Henle intestinal cell line. Log-phase cells of strain PHL67342 attached in greatest numbers to the Henle cells after 45 min of incubation at 37 °C. Attachment to the Henle cells was not affected by D-mannose or D-galactose, but was markedly inhibited by high concentrations of alpha-methyl-D-mannoside. Also, Salmonella lipopolysaccharide had no effect on the attachment of strain PHL67342 to the Henle cells. Fimbriae were not detected on the bacterial cells used in the adherence experiments. These results suggest that some bacterial factor(s) other than fimbriae and lipopolysaccharide mediate the attachment of strain PHL67342 to the Henle cells.

scholarly journals Establishment of fast-growing serum-free immortalised cells from Chinese hamster lung tissues for biopharmaceutical production

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Noriko Yamano-Adachi ◽  
Rintaro Arishima ◽  
Sukwattananipaat Puriwat ◽  
Takeshi Omasa
Keyword(s):  
Cell Line ◽  
Cho Cells ◽  
Mammalian Cells ◽  
High Efficiency ◽  
Chinese Hamster ◽  
Serum Free ◽  
Sterility Testing ◽  
Fast Growing ◽  
Defined Culture

Abstract Chinese hamster (Cricetulus griseus) ovary-derived Chinese hamster ovary (CHO) cells are the most commonly used mammalian hosts for the industrial production of recombinant therapeutics because of their ability to fold, assemble, and perform post-translational modifications, such as glycosylation, on proteins. They are also valuable for their ability to grow in serum-free suspension cultures. In this study, we established a cell line derived from lung tissue of Chinese hamsters, named Chinese hamster lung (CHL)-YN cells. The biosafety of CHL-YN cells was confirmed by in vitro sterility testing, mycoplasma detection, and reverse transcriptase assays. One of the key characteristics of CHL-YN cells was their doubling time of 8.1 h in chemically defined culture medium; thus, they proliferate much faster than conventional CHO cells and general mammalian cells. Transgenes could be introduced into CHL-YN cells with high efficiency. Finally, between 50% to > 100% of the amount of glycosylated immunoglobulin G (IgG)1 produced by CHO-K1 cells was produced by CHL-YN cells over a shorter period of time. In summary, fast-growing CHL-YN cells are a unique cell line for producing recombinant proteins.

scholarly journals Cytotoxic Phenanthrene, Dihydrophenanthrene, and Dihydrostilbene Derivatives and Other Aromatic Compounds from Combretum laxum

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3154
Author(s):  
Eder Bisoli ◽  
Talita Vilalva Freire ◽  
Nídia Cristiane Yoshida ◽  
Walmir Silva Garcez ◽  
Lyara Meira Marinho Queiróz ◽  
...  
Keyword(s):  
Cell Lines ◽  
Cancer Cell ◽  
Mammalian Cells ◽  
Human Cancer ◽  
Radical Scavenging ◽  
Cancer Cell Lines ◽  
In Vitro Cytotoxicity ◽  
Mass Spectrometry Data ◽  
Spectroscopic Techniques

The chemical investigation of the roots and stems of Combretum laxum yielded a new dihydrostilbene derivative, 4′-hydroxy-3,3′,4-trimethoxy-5-(3,4,5-trimethoxyphenoxy)-bibenzyl (1), two phenanthrenes (2–3), and three dihydrophenanthrenes (4–6), along with one lignan, three triterpenoids, one aurone, one flavone, one naphthoquinone, and two benzoic acid derivatives. Their structures were determined by 1D and 2D nuclear magnetic resonance (NMR) spectroscopic techniques and/or mass spectrometry data. The occurrence of dihydrostilbenoid, phenanthrene and dihydrophenanthrene derivatives is unprecedented in a Combretum species native to the American continent. 2,7-Dihydroxy-4,6-dimethoxyphenanthrene, 2,6-dihydroxy-4,7-dimethoxy-9,10-dihydrophenanthrene and 5-O-methyl apigenin are novel findings in the Combretaceae, as is the isolation of compounds belonging to the chemical classes of aurones and naphthoquinones, while (+)-syringaresinol is reported for the first time in the genus Combretum. Compounds 1–6 were also evaluated for their in vitro cytotoxicity against five human cancer cell lines, and radical-scavenging ability against 1,1-diphenyl-2-picryl-hydrazyl (DPPH). 6-Methoxycoelonin (4) was the most cytotoxic against melanoma cells (IC50 2.59 ± 0.11 µM), with a high selectivity index compared with its toxicity against nontumor mammalian cells (SI 25.1). Callosin (6), despite exhibiting the strongest DPPH-scavenging activity (IC50 17.7 ± 0.3 µM), proved marginally inhibitory to the five cancer cell lines tested, indicating that, at least for these cells, antioxidant potential is unrelated to antiproliferative activity.

Synthesis, Cytotoxicity, Antimicrobial and Docking Simulation of Novel Pyrazolo[3,4-d]pyrimidine and pyrazolo[4,3-e][1,2,4]triazolo[3,4-c] pyrimidine Derivatives

2019 ◽  
Vol 19 (8) ◽  
pp. 657-670 ◽  
Author(s):  
Hamdi M. Hassaneen ◽  
Fatma M. Saleh ◽  
Tayseer A. Abdallah ◽  
Magda F. Mohamed ◽  
Yasmin Sh. Mohamed ◽  
...  
Keyword(s):  
Cell Lines ◽  
High Efficiency ◽  
Docking Simulation ◽  
Breast Adenocarcinoma ◽  
Cyclization Reactions ◽  
Pyrimidine Derivatives ◽  
Gram Positive Bacteria ◽  
Antimicrobial Studies ◽  
Hct 116

Background:Isobutyrohydrazonoyl bromide 1 was used as a precursor for the synthesis of 4-imino-3-isopropyl-1-(4-nitrophenyl)-1,4-dihydro-5H-pyrazolo[3,4-d]pyrimidin-5-amine 4, which was converted into hydrazino derivative 5 by heating with hydrazine hydrate at reflux. Hydrazino, as well as imino-amino derivatives, underwent condensation and cyclization reactions to give pyrazolo[ 3,4-d]pyrimidine and pyrazolo[4,3-e][1,2,4]triazolo[3,4-c]pyrimidine derivatives, respectively.Method:Antimicrobial studies are performed using two-gram positive bacteria and two-gram negative bacteria.Results:Data revealed that compound 9a is the most promising antibacterial agent with high efficiency (low MIC value (48 μg/ml)). The cytotoxic assay was investigated for in vitro antitumor screening against Caucasian breast adenocarcinoma MCF7, hepatocellular carcinoma HepG2 and colon carcinoma HCT-116 cell lines.Conclusion:The results are compared with doxorubicin standard anticancer drugs as well as normal cell lines like MCF10 and MCF12. Molecular docking was carried out for the highest potent compound 8c with the binding site of dihydrofolate reductase enzyme DHFR PDB:ID (1DLS).

scholarly journals Nuclear Localization of Japanese Encephalitis Virus Core Protein Enhances Viral Replication

2005 ◽  
Vol 79 (6) ◽  
pp. 3448-3458 ◽  
Author(s):  
Yoshio Mori ◽  
Tamaki Okabayashi ◽  
Tetsuo Yamashita ◽  
Zijiang Zhao ◽  
Takaji Wakita ◽  
...  
Keyword(s):  
Japanese Encephalitis Virus ◽  
Cell Lines ◽  
Japanese Encephalitis ◽  
Nuclear Localization ◽  
Mammalian Cells ◽  
Core Protein ◽  
Encephalitis Virus ◽  
Wild Type ◽  
The Core

ABSTRACT Japanese encephalitis virus (JEV) core protein was detected in both the nucleoli and cytoplasm of mammalian and insect cell lines infected with JEV or transfected with the expression plasmid of the core protein. Mutation analysis revealed that Gly42 and Pro43 in the core protein are essential for the nuclear and nucleolar localization. A mutant M4243 virus in which both Gly42 and Pro43 were replaced by Ala was recovered by plasmid-based reverse genetics. In C6/36 mosquito cells, the M4243 virus exhibited RNA replication and protein synthesis comparable to wild-type JEV, whereas propagation in Vero cells was impaired. The mutant core protein was detected in the cytoplasm but not in the nucleus of either C6/36 or Vero cell lines infected with the M4243 virus. The impaired propagation of M4243 in mammalian cells was recovered by the expression of wild-type core protein in trans but not by that of the mutant core protein. Although M4243 mutant virus exhibited a high level of neurovirulence comparable to wild-type JEV in spite of the approximately 100-fold-lower viral propagation after intracerebral inoculation to 3-week-old mice of strain Jcl:ICR, no virus was recovered from the brain after intraperitoneal inoculation of the mutant. These results indicate that nuclear localization of JEV core protein plays crucial roles not only in the replication in mammalian cells in vitro but also in the pathogenesis of encephalitis induced by JEV in vivo.

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