scholarly journals Construction, Characterization and Application of Recombinant Porcine Deltacoronavirus Expressing Nanoluciferase

Viruses ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1991
Author(s):  
Puxian Fang ◽  
Huichang Zhang ◽  
He Sun ◽  
Gang Wang ◽  
Sijin Xia ◽  
...  
Keyword(s):  
Cell Lines ◽  
High Throughput Screening ◽  
Reverse Genetics ◽  
Infectious Clone ◽  
Artificial Chromosome ◽  
Antiviral Drugs ◽  
Reporter Virus ◽  
Suckling Piglets ◽  
One Step

Porcine deltacoronavirus (PDCoV), an emerging enteropathogenic coronavirus, causes diarrhoea in suckling piglets and has the potential for cross-species transmission. No effective PDCoV vaccines or antiviral drugs are currently available. Here, we successfully generated an infectious clone of PDCoV strain CHN-HN-2014 using a combination of bacterial artificial chromosome (BAC)-based reverse genetics system with a one-step homologous recombination. The recued virus (rCHN-HN-2014) possesses similar growth characteristics to the parental virus in vitro. Based on the established infectious clone and CRISPR/Cas9 technology, a PDCoV reporter virus expressing nanoluciferase (Nluc) was constructed by replacing the NS6 gene. Using two drugs, lycorine and resveratrol, we found that the Nluc reporter virus exhibited high sensibility and easy quantification to rapid antiviral screening. We further used the Nluc reporter virus to test the susceptibility of different cell lines to PDCoV and found that cell lines derived from various host species, including human, swine, cattle and monkey enables PDCoV replication, broadening our understanding of the PDCoV cell tropism range. Taken together, our reporter viruses are available to high throughput screening for antiviral drugs and uncover the infectivity of PDCoV in various cells, which will accelerate our understanding of PDCoV.

scholarly journals Development and Characterization of a cDNA-Launch Recombinant Simian Hemorrhagic Fever Virus Expressing Enhanced Green Fluorescent Protein: ORF 2b’ Is Not Required for In Vitro Virus Replication

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 632
Author(s):  
Yingyun Cai ◽  
Shuiqing Yu ◽  
Ying Fang ◽  
Laura Bollinger ◽  
Yanhua Li ◽  
...  
Keyword(s):  
Green Fluorescent Protein ◽  
Cell Lines ◽  
Enhanced Green Fluorescent Protein ◽  
Fluorescent Protein ◽  
Infectious Clone ◽  
Hemorrhagic Fever ◽  
Simian Hemorrhagic Fever Virus ◽  
Hemorrhagic Fever Virus ◽  
Green Fluorescent

Simian hemorrhagic fever virus (SHFV) causes acute, lethal disease in macaques. We developed a single-plasmid cDNA-launch infectious clone of SHFV (rSHFV) and modified the clone to rescue an enhanced green fluorescent protein-expressing rSHFV-eGFP that can be used for rapid and quantitative detection of infection. SHFV has a narrow cell tropism in vitro, with only the grivet MA-104 cell line and a few other grivet cell lines being susceptible to virion entry and permissive to infection. Using rSHFV-eGFP, we demonstrate that one cricetid rodent cell line and three ape cell lines also fully support SHFV replication, whereas 55 human cell lines, 11 bat cell lines, and three rodent cells do not. Interestingly, some human and other mammalian cell lines apparently resistant to SHFV infection are permissive after transfection with the rSHFV-eGFP cDNA-launch plasmid. To further demonstrate the investigative potential of the infectious clone system, we introduced stop codons into eight viral open reading frames (ORFs). This approach suggested that at least one ORF, ORF 2b’, is dispensable for SHFV in vitro replication. Our proof-of-principle experiments indicated that rSHFV-eGFP is a useful tool for illuminating the understudied molecular biology of SHFV.

scholarly journals Sequences in pol Are Required for Transfer of Human Foamy Virus-Based Vectors

1998 ◽  
Vol 72 (7) ◽  
pp. 5510-5516 ◽  
Author(s):  
Otto Erlwein ◽  
Paul D. Bieniasz ◽  
Myra O. McClure
Keyword(s):  
Cell Lines ◽  
Foamy Virus ◽  
Infectious Clone ◽  
Helper Virus ◽  
Kidney Cells ◽  
Human Foamy Virus ◽  
Vector Systems ◽  
Sequence Requirements ◽  
Baby Hamster Kidney Cells

ABSTRACT A series of vectors with heterologous genes was constructed from HSRV1, an infectious clone of human foamy virus (HFV), and transfected into baby hamster kidney cells to generate stably transfected vector cell lines. Two cis-acting sequences were required to achieve efficient rescue by helper virus. The first element was located at the 5′ end upstream of position 1274 of the proviral DNA. Interestingly, a mutation in the leader sequence which decreased the ability to dimerize in vitro inhibited transfer by helper HFV. A second element that was important for vector transfer was located in thepol gene between positions 5638 and 6317. Constructs lacking this element were only poorly transferred by helper HFV, even though their RNA was produced in the vector cell lines. This finding rules out the possibility that the observed lack of transfer was due to RNA instability. A minimal vector containing only these two elements could be successfully delivered by helper HFV, confirming that all essential cis-acting sequences were present. The presence of a sequence described as a second polypurine tract in HFV was not necessary for transfer. Our data identified the minimal sequence requirements for HFV vector transfer for the development of useful vector systems.

Influence of amide versus ester linkages on the anticancer properties of the new flavone–biotin conjugates

2019 ◽  
Vol 74 (7-8) ◽  
pp. 193-200
Author(s):  
Monika Stompor ◽  
Marta Świtalska ◽  
Agata Bajek ◽  
Joanna Wietrzyk
Keyword(s):  
Cell Lines ◽  
Amide Bond ◽  
Step Method ◽  
Fluorescent Reporter ◽  
Bifunctional Molecules ◽  
Anticancer Properties ◽  
One Step ◽  
3T3 Cell Lines ◽  
Mcf 7

Abstract Novel biotinylated C-6 substituted flavones were synthesised by a one-step method that connects biotin to 6-hydroxyflavone and 6-aminoflavone by esterification and amidation of hydroxyl and amino groups, respectively. The obtained compounds, 6-O-biotinylflavone and 6-biotinylamidoflavone, are the bifunctional molecules composed of a flavone moiety as a fluorescent reporter and biotin as a cancer-targeting unit. Antiproliferative activity was evaluated using SRB assays in MCF-7, MCF-10A, HepG2, MDA-MB-231, 4T1, and Balb/3T3 cell lines. In vitro evaluation revealed that compounds with biotin moiety displayed better cell selectivity between the cancer and normal cells than the parental substrates. These results indicate that anticancer effect is not related to the position of biotin moiety, but it is related to the presence of ester or amide bond. 6-O-Biotinylflavone was more active than 6-hydroxyflavone against human breast (MDA-MB-231) and liver (HepG2) cancer cells with IC50 (concentration of tested agent that inhibits proliferation of the cell population by 50%) values equal to 78.5 ± 18.8 μM and 133.2 ± 14.2 μM, respectively. Non biotinylated 6-aminoflavone was more active than 6-biotinylamidoflavone against all tested cell lines, with IC50 values between 34.3 ± 9.1 μM (4T1) and 173.86 ± 24.3 μM (MCF-7).

scholarly journals Recovery of NanoLuc Luciferase-Tagged Canine Distemper Virus for Facilitating Rapid Screening of Antivirals in vitro

2020 ◽  
Vol 7 ◽  
Author(s):  
Fuxiao Liu ◽  
Qianqian Wang ◽  
Yilan Huang ◽  
Ning Wang ◽  
Youming Zhang ◽  
...  
Keyword(s):  
High Throughput ◽  
High Throughput Screening ◽  
Canine Distemper Virus ◽  
Reverse Genetics ◽  
Rapid Screening ◽  
Canine Distemper ◽  
Virus Propagation ◽  
The Family ◽  
Conventional Methods

Canine distemper virus (CDV), belonging to the genus Morbillivirus in the family Paramyxoviridae, is a highly contagious pathogen, affecting various domestic, and wild carnivores. Conventional methods are too cumbersome to be used for high-throughput screening of anti-CDV drugs. In this study, a recombinant CDV was rescued using reverse genetics for facilitating screening of anti-CDV drug in vitro. The recombinant CDV could stably express the NanoLuc® luciferase (NLuc), a novel enzyme that was smaller and “brighter” than others. The intensity of NLuc-catalyzed luminescence reaction indirectly reflected the anti-CDV effect of a certain drug, due to a positive correlation between NLuc expression and virus propagation in vitro. Based on such a characteristic feature, the recombinant CDV was used for anti-CDV assays on four drugs (ribavirin, moroxydine hydrochloride, 1-adamantylamine hydrochloride, and tea polyphenol) via analysis of luciferase activity, instead of via conventional methods. The result showed that out of these four drugs, only the ribavirin exhibited a detectable anti-CDV effect. The NLuc-tagged CDV would be a rapid tool for high-throughput screening of anti-CDV drugs.

Flavoperidol as a novel therapeutic agent for bladder cancer.

2017 ◽  
Vol 35 (6_suppl) ◽  
pp. 357-357 ◽  
Author(s):  
Reema Railkar ◽  
Thomas Sanford ◽  
Spencer Krane ◽  
Q. Quentin Li ◽  
Piyush K. Agarwal
Keyword(s):  
Bladder Cancer ◽  
Cell Lines ◽  
High Throughput ◽  
High Throughput Screening ◽  
Molecular Size ◽  
Effective Inhibitor ◽  
Primary Bladder ◽  
New Treatments

357 Background: Bladder cancer (CaB) is the 4th most common cancer among men in the US but receives substantially less research resources than many other cancer types. There has been little change to the management of bladder cancer over the past 25 years. Quantitative high throughput screening (qHTS) of representative cancer lines with oncology drugs may identify new treatments or re-purpose already existing therapies for different disease. We utilized this technique to identify new therapies in three primary bladder lines (RT4, T24, and UMUC3) and their metastatic lines (T24T, SLT3 and FL3 for T24 and LUL-2 for UMUC3). Methods: We screened 8 bladder cancer cell lines (including RT4, T24, and UMUC3) against 1,912 oncology drugs using a 48 hour cell proliferation assay with an ATP−based readout to determine activity and potency of compounds in a dose response manner. One of the candidate drugs inhibitory in all cell lines tested is flavopiridol, a pan CDK inhibitor. We further characterized the mechanism of action and in vivo effects of flavopiridol using various cell based assays and mouse xenograft studies. Results: The initial screen identified 95 compounds active in 8 cell lines. The top 50 compounds were further analyzed for molecular size of >200 g/mol and TPSA<90. This identified mitomycin C and 8 novel compounds. Further testing revealed Flavopiridol to be most consistent with qHTS data having IC50 of 100-300nM in all the cell lines tested. Flavopiridol induces G2/M arrest; however, very little apoptosis was seen suggesting a cytostatic rather than a cytotoxic mechanism of flavopiridol action. Flavopiridol showed dose dependent inhibition of migration, invasion and colony formation in all cell lines tested. Xenograft studies in rapidly growing UMUC-3 cells showed slowing of tumor growth but not complete reduction indicating cytostatic mechanism of flavopiridol. Conclusions: A high throughput drug screen can identify novel compounds in bladder cancer. Flavopiridol seems to be a very effective inhibitor both in vitro and in vivo. Physical properties of Flavopiridol are most suited for intravesical use, which may lead to it being an effective inhibitor of CaB in the bladder at higher doses without any/few systemic toxicities.

scholarly journals The 164 K, 165 K, and 167 K residues of VP1 are vital for goose parvovirus proliferation in GEFs based on PCR-based reverse genetics system

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Peng Liu ◽  
Liqin Yang ◽  
Jingyue Zhang ◽  
Tao Wang ◽  
Yuanyuan Wu ◽  
...  
Keyword(s):  
Nuclear Import ◽  
Reverse Genetics ◽  
Clinical Sample ◽  
Infectious Clone ◽  
Progeny Virus ◽  
Infectious Clones ◽  
Goose Parvovirus ◽  
Growth Character ◽  
Full Length Genome

Abstract Background Goose parvovirus (GPV) is the etiological agent of Derzsy’s disease and is fatal for gosling. Research on the molecular basis of GPV pathogenicity has been hampered by the lack of a reliable reverse genetics system. At present, the GPV infectious clone has been rescued by transfection in the goose embryo, but the growth character of it is unclear in vitro. Methods In this study, we identified the full-length genome of GPV RC16 from the clinical sample, which was cloned into the pACYC177, generating the pIRC16. The recombinant virus (rGPV RC16) was rescued by the transfection of pIRC16 into goose embryo fibroblasts (GEFs). The rescued virus was characterized by whole genome sequencing, indirect immunofluorescence assays (IFA) and western blot (WB) using rabbit anti-GPV Rep polyclonal antibody as the primary antibody. Previously, we found the 164 K, 165 K, and 167 K residues in the 160YPVVKKPKLTEE171 are required for the nuclear import of VP1 (Chen S, Liu P, He Y, et al. Virology 519:17–22). According to that, the GPV infectious clones with mutated K164A, K165A, or K167A in VP1 were constructed, rescued and passaged. Results The rGPV RC16 has been successfully rescued by transfection of pIRC16 into the GEFs and can proliferate in vitro. Furthermore, the progeny virus produced by pIRC16 transfected cells was infectious in GEFs. Moreover, mutagenesis experiments showed that the rGPV RC16 with mutated 164 K, 165 K and 167 K in VP1 could not proliferate in GEFs based on the data of IFA and WB in parental virus and progeny virus. Conclusions The rGPV RC16 containing genetic maker and the progeny virus are infectious in GEFs. The 164 K, 165 K, and 167 K of VP1 are vital for the proliferation of rGPV RC16 in vitro.

Leishmania (V.) guyanensis: isolation and characterization of glucantime-resistant cell lines

1996 ◽  
Vol 42 (9) ◽  
pp. 944-949 ◽  
Author(s):  
K. C. Ferreira-Pinto ◽  
A. L. Miranda-Vilela ◽  
C. Anacleto ◽  
A. P. S. M. Fernandes ◽  
M. C. B. Abdo ◽  
...  
Keyword(s):  
Cell Lines ◽  
Blot Hybridization ◽  
Resistant Cell ◽  
Cross Resistance ◽  
Isolation And Characterization ◽  
Stability Of Resistance ◽  
One Step ◽  
The Stability ◽  
The One

A glucantime sensitive Leishmania (V.) guyanensis strain was used to obtain in vitro resistant cell lines, by increments in glucantime concentrations employing both one step and stepwise protocols. Whereas the effective concentration of drug that inhibited the growth of wild type cells by 50% (EC50 value) was 0.20 mg Sbv/mL, the resistant cells were able to grow in glucantime concentrations greater than 8.0 mg/mL. The resistant cell lines were partially characterized by their in vitro response to glucantime, the stability of resistance phenotype, cross resistance to a range of drugs, and also by the analysis of total DNA fragments generated by restriction endonucleases and blot hybridization. Amplified DNA sequence similar to a P-glycoprotein analog from Leishmania tarentolae (ltpgpA gene) was observed in all the resistant cell lines obtained through the one-step protocol. These cell lines showed cross resistance to heavy metals but were sensitive to puromycin, vinblastine, and pentostam.Key words: Leishmania, glucantime resistance, pentavalent antimony, gene amplification.

scholarly journals Establishment and Application of in Vitro Membrane Potential Assays in Cell Lines with Endogenous or Recombinant Expression of ATP-Sensitive Potassium Channels (Kir6.2/SUR1) Using a Fluorescent Probe Kit

2004 ◽  
Vol 9 (5) ◽  
pp. 382-390 ◽  
Author(s):  
Per Arkhammar ◽  
Philip Wahl ◽  
Berit Gerlach ◽  
Tinna Fremming ◽  
John B. Hansen
Keyword(s):  
Membrane Potential ◽  
Potassium Channel ◽  
Cell Lines ◽  
High Throughput Screening ◽  
Rank Order ◽  
Recombinant Expression ◽  
Whole Body ◽  
In Vitro Assays ◽  
Resting Membrane Potential

The flow of current through the adenosine triphosphate (ATP)-sensitive potassium channel (KATP) of the isoform Kir6.2/SUR1 regulates the resting membrane potential in the pancreatic β-cell. In combination with the cellular glucose metabolism, it is an important minute-to-minute regulator of insulin secretion and whole-body glucose homeostasis. The same KATP isoform is further reported to be present in glucagon-secreting α-cells, intestinal L-cells, and glucose-responsive neurons in the hypothalamus. All in all, this makes Kir6.2/SUR1 an interesting drug target. Using a commercially available fluorescent membrane potential probe kit and a conventional 96-well fluorescence plate reader, the authors have developed and established qualitative membrane potential assays used to screen for potassium channel closers (KCCs) and openers (KCOs) in insulin- and glucagon-secreting cell lines as well as in cells with recombinant expression of the human Kir6.2/SUR1 channel complex. Both glucose- and KCC-induced depolarization could be demonstrated. The magnitudes of these responses and KCO-induced repolarization at high glucose displayed some variation between the different cell lines but a similar rank order of test compounds. Some cell types required the presence of a KCC, such as tolbutamide, to display significant effects of KCOs. The authors find that robust and reliable functional in vitro assays compatible with medium-throughput screening and high-throughput screening can be developed as a base for finding new, more potent, and isoform-selective KCCs and KCOs.

scholarly journals Development of a Cell-Based Reporter Assay for Screening of Inhibitors of Hypoxia-Inducible Factor 2-Induced Gene Expression

2006 ◽  
Vol 11 (6) ◽  
pp. 678-687 ◽  
Author(s):  
Girma M. Woldemichael ◽  
James R. Vasselli ◽  
Roberta S. Gardella ◽  
Tawnya C. Mckee ◽  
W. Marston Linehan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Lines ◽  
High Throughput ◽  
High Throughput Screening ◽  
Dynamic Range ◽  
Clear Cell ◽  
Hypoxia Inducible Factor ◽  
Luciferase Reporter ◽  
Reporter Cell

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.

scholarly journals Recovery of Synthetic Zika Virus Based on Rio-U1 Isolate Using a Genetically Stable Two Plasmid System and cDNA Amplification

2021 ◽  
Vol 12 ◽  
Author(s):  
Iasmim Silva de Mello ◽  
Déberli Ruiz Fernandes ◽  
Nathália Dias Furtado ◽  
Alexandre Araújo Cunha dos Santos ◽  
Marta Pereira dos Santos ◽  
...  
Keyword(s):  
Reverse Genetics ◽  
Infectious Clone ◽  
Pcr Amplification ◽  
Functional Studies ◽  
Proliferation Capacity ◽  
Similar Disease ◽  
Stable Plasmid ◽  
Immunocompromised Mice

In 2016, the world experienced the unprecedented Zika epidemic. The ZIKV emerged as a major human pathogen due to its association with the impairment of perinatal development and Guillain–Barré syndrome. The occurrence of these severe cases of Zika points to the significance of studies for understanding the molecular determinants of flavivirus pathogenesis. Reverse genetics is a powerful method for studying the replication and determinants of pathogenesis, virulence, and viral attenuation of flaviviruses, facilitating the design of vaccines and therapeutics. However, the main hurdle in the development of infectious clones is the instability of full-length cDNA in Escherichia coli. Here, we described the development of a genetically stable and efficient infectious clone based on the ZIKV Rio-U1 isolated in the 2016 epidemic in Brazil. The employed strategy consisted of cloning the viral cDNA genome into two stable plasmid subclones and obtaining a high-quality cDNA template with increment in DNA mass for in vitro transcription by PCR amplification. The strategy for developing a ZIKV infectious cDNA clone designed in this study was successful, yielding a replicative and efficient clone-derived virus with high similarities with its parental virus, Rio-U1, by comparison of the proliferation capacity in mammal and insect cells. The infection of AG129 immunocompromised mice caused identical mortality rates, with similar disease progression and morbidity in the animals infected with the parental and the cDNA-derived virus. Histopathological analyses of mouse brains infected with the parental and the cDNA-derived viruses revealed a similar pathogenesis degree. We observed meningoencephalitis, cellular pyknosis, and neutrophilic invasion adjacent to the choroid plexus and perivascular cuffs with the presence of neutrophils. The developed infectious clone will be a tool for genetic and functional studies in vitro and in vivo to understand viral infection and pathogenesis better.

Sign in / Sign up

Export Citation Format

Share Document