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1

Chan, Eva, Gabrielle Heilek-Snyder, Nick Cammack, Surya Sankuratri, and Changhua Ji. "Development of a Moloney Murine Leukemia Virus-Based Pseudotype Anti-HIV Assay Suitable for Accurate and Rapid Evaluation of HIV Entry Inhibitors." Journal of Biomolecular Screening 11, no. 6 (June 7, 2006): 652–63. http://dx.doi.org/10.1177/1087057106288881.

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Анотація:
There has been increasing interest in the identification of novel HIV entry inhibitors. For the discovery of these entry inhibitors, robust surrogate anti-HIV assays are highly desired. The authors report a novel anti-HIV assay system using Moloney murine leukemia viruses (MMLVs) pseudotyped with cytoplasmic tail-truncated HIV envelope protein gp140. These pseudotyped MMLV-HIVgp140 viral particles carry luciferase transcripts; therefore, robust luciferase signal can be detected in cells infected by these pseudotypes. Polycationic agent polybrene and spinoculation markedly enhanced the infection efficiency of these pseudotypes. It was demonstrated that the tropism of these pseudotypes is dependent on the pseudotyped HIV envelope proteins. MMLV viruses pseudotyped with gp140 from an R5 HIV virus specifically infect CCR5-expressing cells, and viruses pseudotyped with gp140 from an X4 HIV virus specifically infect CXCR4-expressing cells. Furthermore, CCR5 antagonists inhibited only MMLV-gp140(R5) infections, and CXCR4 antagonists inhibited only MMLV-gp140(X4) infections. A variety of known HIV entry inhibitors were tested in both R5- and X4-dependent pseudotype antiviral assays, and the IC50 values generated were consistent with published results. The pseudotype antiviral assay was also used in the characterization of hundreds of novel CCR5 antagonists. The IC50 values determined in this assay were compared with those determined in HIV antiviral and cell-cell fusion (CCF) assays, and good correlation was found between pseudotype antiviral assay and HIV antiviral assay ( R2 = 0.9) or CCF assay ( R2 = 0.8).
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2

Bruett, Linda, and Janice E. Clements. "Functional Murine Leukemia Virus Vectors Pseudotyped with the Visna Virus Envelope Show Expanded Visna Virus Cell Tropism." Journal of Virology 75, no. 23 (December 1, 2001): 11464–73. http://dx.doi.org/10.1128/jvi.75.23.11464-11473.2001.

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Анотація:
ABSTRACT Pseudotype virus vectors serve as a powerful tool for the study of virus receptor usage and entry. We describe the development of murine leukemia virus (MuLV) particles pseudotyped with the visna virus envelope glycoprotein and encoding a green fluorescent protein reporter as a tool to study the expression of the visna virus receptor. Functional MuLV/visna virus pseudotypes were obtained when the cytoplasmic tail of the visna virus envelope TM protein was truncated to 3, 7, or 11 amino acids in length. MuLV/visna virus particles were used to transduce a panel of cell types from various organisms, including sheep, goat, human, hamster, mouse, monkey, and quail. The majority of the cells examined were susceptible to MuLV/visna pseudotype viruses, supporting the notion that the visna virus cellular receptor is a widely expressed protein found in many species. Of 16 different cell types tested, only mouse embryo fibroblast NIH 3T3 cells, hamster ovary CHO cells, and the human promonocyte cell line U937 cells were not susceptible to transduction by the pseudotyped virus. The production of functional MuLV/visna virus pseudotypes has provided a sensitive, biologically relevant system to study visna virus cell entry and envelope-receptor interactions.
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3

Poluri, Ananthalakshmi, Rebecca Ainsworth, Scott C. Weaver, and Richard E. Sutton. "Functional Pseudotyping of Human Immunodeficiency Virus Type 1 Vectors by Western Equine Encephalitis Virus Envelope Glycoprotein." Journal of Virology 82, no. 24 (October 8, 2008): 12580–84. http://dx.doi.org/10.1128/jvi.01503-08.

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Анотація:
ABSTRACT We investigated the ability of western equine encephalitis virus envelope glycoproteins (WEEV GP) to pseudotype lentiviral vectors. The titers of WEEV GP-pseudotyped human immunodeficiency virus type 1 (HIV) ranged as high as 8.0 × 104 IU/ml on permissive cells. Sera from WEEV-infected mice specifically neutralized these pseudotypes; cell transduction was also sensitive to changes in pH. The host range of the pseudotyped particles in vitro was somewhat limited, which is atypical for most alphaviruses. HIV vectors pseudotyped by WEEV GP may be a useful tool for characterizing WEEV cell binding and entry and screening for small-molecule inhibitors.
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4

Codran, Audrey, Cathy Royer, Daniel Jaeck, Michèle Bastien-Valle, Thomas F. Baumert, Marie Paule Kieny, Carlos Augusto Pereira, and Jean-Pierre Martin. "Entry of hepatitis C virus pseudotypes into primary human hepatocytes by clathrin-dependent endocytosis." Journal of General Virology 87, no. 9 (September 1, 2006): 2583–93. http://dx.doi.org/10.1099/vir.0.81710-0.

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Анотація:
Hepatitis C virus (HCV) is a major cause of chronic hepatitis worldwide. Studies of the early steps of HCV infection have been hampered by the lack of convenient in vitro or in vivo models. Although several cell-surface molecules that mediate the binding of HCV envelope proteins to target cells have been identified, mechanisms of viral entry into human hepatocytes are still poorly understood. Vesicular stomatitis virus/HCV pseudotyped viruses expressing the HCV envelope glycoproteins on the viral envelope were generated and it was found that their entry into human hepatocytes required co-expression of E1 and E2 on the pseudotype surface. Neutralization of pseudotype infection by anti-HCV antibodies suggested that cellular entry was mediated by HCV envelope glycoproteins and by previously characterized cell-surface molecules, including CD81. An entry assay based on the release of a fluorochrome from labelled HCV pseudotypes provided evidence for a pH-dependent fusion of the pseudotype envelope with a cellular compartment. By using a panel of endocytosis inhibitors, it is postulated that penetration of HCV into primary cultures of hepatocytes takes place by clathrin-mediated endocytosis.
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5

Kretschmer, Maibritt, Patrycja Kadlubowska, Daniel Hoffmann, Birco Schwalbe, Heidi Auerswald, and Michael Schreiber. "Zikavirus prME Envelope Pseudotyped Human Immunodeficiency Virus Type-1 as a Novel Tool for Glioblastoma-Directed Virotherapy." Cancers 12, no. 4 (April 18, 2020): 1000. http://dx.doi.org/10.3390/cancers12041000.

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Анотація:
Glioblastoma multiforme is the most lethal type of brain tumor that is not yet curable owing to its frequent resurgence after surgery. Resistance is mainly caused by the presence of a subpopulation of tumor cells, the glioma stem cells (GSCs), which are highly resistant to radiation and chemotherapy. In 2015, Zikavirus (ZIKV)-induced microcephaly emerged in newborns, indicating that ZIKV has a specific neurotropism. Accordingly, an oncolytic tropism for infecting GSCs was demonstrated in a murine tumor model. Like other flaviviruses, ZIKV is enveloped by two proteins, prM and E. The pME expression plasmid along with the HIV-1 vector pNL Luc AM generated prME pseudotyped viral particles. Four different prME envelopes, Z1 to Z4, were cloned, and the corresponding pseudotypes, Z1- to Z4-HIVluc, produced by this two-plasmid system, were tested for entry efficiency using Vero-B4 cells. The most efficient pseudotype, Z1-HIVluc, also infected glioma-derived cell lines U87 and 86HG39. The pseudotype system was then extended by using a three-plasmid system including pME-Z1, the HIV-1 packaging plasmid psPAX2, and the lentiviral vector pLenti-luciferase-P2A-Neo. The corresponding pseudotype, designated Z1-LENTIluc, also infected U87 and 86HG39 cells. Altogether, a pseudotyped virus especially targeting glioma-derived cells might be a promising candidate for a prospective glioblastoma-directed virotherapy.
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6

Spiegel, Martin, Michael Bitzer, Andrea Schenk, Heidi Rossmann, Wolfgang J. Neubert, Ursula Seidler, Michael Gregor, and Ulrich Lauer. "Pseudotype Formation of Moloney Murine Leukemia Virus with Sendai Virus Glycoprotein F." Journal of Virology 72, no. 6 (June 1, 1998): 5296–302. http://dx.doi.org/10.1128/jvi.72.6.5296-5302.1998.

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ABSTRACT Mixed infection of cells with both Moloney murine leukemia virus (MoMLV) and related or heterologous viruses produces progeny pseudotype virions bearing the MoMLV genome encapsulated by the envelope of the other virus. In this study, pseudotype formation between MoMLV and the prototype parainfluenza virus Sendai virus (SV) was investigated. We report for the first time that SV infection of MoMLV producer cells results in the formation of MoMLV(SV) pseudotypes, which display a largely extended host range compared to that of MoMLV particles. This could be associated with SV hemagglutinin-neuraminidase (SV-HN) glycoprotein incorporation into MoMLV envelopes. In contrast, solitary incorporation of the other SV glycoprotein, SV fusion protein (SV-F), resulted in a distinct and narrow extension of the MoMLV host range to asialoglycoprotein receptor (ASGP-R)-positive cells (e.g., cultured human hepatoma cells). Since stably ASGP-R cDNA-transfected MDCK cells, but not parental ASGP-R-negative MDCK cells, were found to be transduced by MoMLV(SV-F) pseudotypes and transduction of ASGP-R-expressing cells was found to be inhibited by ASGP-R antiserum, a direct proof for the ASGP-R-restricted tropism of MoMLV(SV-F) pseudotypes was provided. Cultivation of ASGP-R-positive HepG2 hepatoma cells on Transwell-COL membranes led to a significant enhancement of MoMLV(SV-F) titers in subsequent flowthrough transduction experiments, thereby suggesting the importance of ASGP-R accessibility at the basolateral domain for MoMLV(SV-F) pseudotype transduction. The availability of such ASGP-R-restricted MoMLV(SV-F)-pseudotyped vectors opens up new perspectives for future liver-restricted therapeutic gene transfer applications.
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7

Meyer, Keith, Aster Beyene, Terry L. Bowlin, Arnab Basu, and Ranjit Ray. "Coexpression of Hepatitis C Virus E1 and E2 Chimeric Envelope Glycoproteins Displays Separable Ligand Sensitivity and Increases Pseudotype Infectious Titer." Journal of Virology 78, no. 23 (December 1, 2004): 12838–47. http://dx.doi.org/10.1128/jvi.78.23.12838-12847.2004.

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ABSTRACT We have previously reported that a pseudotype virus generated by reconstitution of hepatitis C virus (HCV) chimeric envelope glycoprotein E1-G or E2-G on the surface of a temperature-sensitive mutant of vesicular stomatitis virus (VSVts045) interacts independently with mammalian cells to initiate infection. Here, we examined whether coexpression of both of the envelope glycoproteins on pseudotype particles would augment virus infectivity and/or alter the functional properties of the individual subunits. Stable transfectants of baby hamster kidney (BHK) epithelial cells expressing either one or both of the chimeric envelope glycoproteins of HCV on the cell surface were generated. The infectious titer of the VSV pseudotype, derived from a stable cell line incorporating both of the chimeric glycoproteins of HCV, was ∼4- to 5-fold higher than that of a pseudotype bearing E1-G alone or ∼25- to 30-fold higher than that of E2-G alone when assayed with a number of mammalian cell lines. Further studies suggested that that the E1-G/E2-G or E2-G pseudotype was more sensitive to the inhibitory effect of heparin than the E1-G pseudotype. Treatment of the E1-G/E2-G pseudotype with a negatively charged sulfated sialyl lipid (NMSO3) displayed a ∼4-fold-higher sensitivity to neutralization than pseudotypes with either of the two individual glycoproteins. In contrast, VSVts045, used as a backbone for the generation of pseudotypes, displayed at least 20-fold-higher sensitivity to NMSO3-mediated inhibition of virus plaque formation. The effect of low-density lipoprotein on the E1-G pseudotype was greater than that apparent for the E1-G/E2-G pseudotype. The treatment of cells with monoclonal antibodies to CD81 displayed an inhibitory effect upon the pseudotype with E1-G/E2-G or with E2-G alone. Taken together, our results indicate that the HCV E1 and E2 glycoproteins have separable functional properties and that the presence of these two envelope glycoproteins on VSV/HCV pseudotype particles increases infectious titer.
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8

Pöhlking, Celine, Sebastian Beier, Jan Patrick Formanski, Michael Friese, Michael Schreiber, and Birco Schwalbe. "Isolation of Cells from Glioblastoma Multiforme Grade 4 Tumors for Infection with Zika Virus prME and ME Pseudotyped HIV-1." International Journal of Molecular Sciences 24, no. 5 (February 24, 2023): 4467. http://dx.doi.org/10.3390/ijms24054467.

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Анотація:
This study aimed to isolate cells from grade 4 glioblastoma multiforme tumors for infection experiments with Zika virus (ZIKV) prME or ME enveloped HIV-1 pseudotypes. The cells obtained from tumor tissue were successfully cultured in human cerebrospinal fluid (hCSF) or a mixture of hCSF/DMEM in cell culture flasks with polar and hydrophilic surfaces. The isolated tumor cells as well as the U87, U138, and U343 cells tested positive for ZIKV receptors Axl and Integrin αvβ5. Pseudotype entry was detected by the expression of firefly luciferase or green fluorescent protein (gfp). In prME and ME pseudotype infections, luciferase expression in U-cell lines was 2.5 to 3.5 logarithms above the background, but still two logarithms lower than in the VSV-G pseudotype control. Infection of single cells was successfully detected in U-cell lines and isolated tumor cells by gfp detection. Even though prME and ME pseudotypes had low infection rates, pseudotypes with ZIKV envelopes are promising candidates for the treatment of glioblastoma.
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9

Sandrin, Virginie, Delphine Muriaux, Jean-Luc Darlix, and François-Loïc Cosset. "Intracellular Trafficking of Gag and Env Proteins and Their Interactions Modulate Pseudotyping of Retroviruses." Journal of Virology 78, no. 13 (July 1, 2004): 7153–64. http://dx.doi.org/10.1128/jvi.78.13.7153-7164.2004.

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Анотація:
ABSTRACT Glycoproteins derived from most retroviruses and from several families of enveloped viruses can form infectious pseudotypes with murine leukemia virus (MLV) and lentiviral core particles, like the MLV envelope glycoproteins (Env) that are incorporated on either virus type. However, coexpression of a given glycoprotein with heterologous core proteins does not always give rise to highly infectious viral particles, and restrictions on pseudotype formation have been reported. To understand the mechanisms that control the recruitment of viral surface glycoproteins on lentiviral and retroviral cores, we exploited the fact that the feline endogenous retrovirus RD114 glycoprotein does not efficiently pseudotype lentiviral cores derived from simian immunodeficiency virus, whereas it is readily incorporated onto MLV particles. Our results indicate that recruitment of glycoproteins by the MLV and lentiviral core proteins occurs in intracellular compartments and not at the cell surface. We found that Env and core protein colocalization in intracytoplasmic vesicles is required for pseudotype formation. By investigating MLV/RD114 Env chimeras, we show that signals in the cytoplasmic tail of either glycoprotein differentially influenced their intracellular localization; that of MLV allows endosomal localization and hence recruitment by both lentiviral and MLV cores. Furthermore, we found that upon membrane binding, MLV core proteins could relocalize Env glycoproteins in late endosomes and allow their incorporation on viral particles. Thus, intracellular colocalization, as well as interactions between Env and core proteins, may influence the recruitment of the glycoprotein onto viral particles and generate infectious pseudotyped viruses.
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10

Balliet, John W., and Paul Bates. "Efficient Infection Mediated by Viral Receptors Incorporated into Retroviral Particles." Journal of Virology 72, no. 1 (January 1, 1998): 671–76. http://dx.doi.org/10.1128/jvi.72.1.671-676.1998.

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Анотація:
ABSTRACT Many host cell surface proteins, including viral receptors, are incorporated into enveloped viruses. To address the functional significance of these host proteins, murine leukemia viruses containing the cellular receptors for Rous sarcoma virus (Tva) or ecotropic murine leukemia virus (MCAT-1) were produced. These receptor-pseudotyped viruses efficiently infect cells expressing the cognate viral envelope glycoproteins, with titers of up to 105 infectious units per milliliter for the Tva pseudotypes. Receptor and viral glycoprotein specificity and functional requirements are maintained, suggesting that receptor pseudotype infection recapitulates events of normal viral entry. The ability of the Tva and MCAT-1 pseudotypes to infect cells efficiently suggests that, in contrast to human immunodeficiency virus type 1 entry, neither of these retroviral receptors requires a coreceptor for membrane fusion. In addition, the ability of receptor pseudotypes to target infected cells suggests that they may be useful therapeutic reagents for directing infection of viral vectors. Receptor-pseudotyped viruses may be useful for identifying new viral receptors or for defining functional requirements of known receptors. Moreover, this work suggests that the production of receptor pseudotypes in vivo could provide a mechanism for expanded viral tropism with potential effects on the pathogenesis and evolution of the virus.
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11

Kahl, Christoph A., Jon Marsh, Joanne Fyffe, David A. Sanders, and Kenneth Cornetta. "Human Immunodeficiency Virus Type 1-Derived Lentivirus Vectors Pseudotyped with Envelope Glycoproteins Derived from Ross River Virus and Semliki Forest Virus." Journal of Virology 78, no. 3 (February 1, 2004): 1421–30. http://dx.doi.org/10.1128/jvi.78.3.1421-1430.2004.

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ABSTRACT Ross River virus (RRV) and Semliki Forest virus (SFV) are two alphaviruses that have a high degree of amino acid homology, as well as a very broad host range. We show here that envelope glycoproteins derived from both viruses can pseudotype human immunodeficiency virus type 1 (HIV-1)-derived lentivirus vectors. Both RRV and SFV glycoproteins considerably expand the host range of the lentivirus vector, and vectors can be efficiently concentrated by ultracentrifugation. A systematic analysis comparing the alphaviral glycoproteins to the vesicular stomatitis virus glycoprotein (VSV-G) revealed that lentivirus vectors incorporate RRV glycoproteins with an efficiency comparable to that of VSV-G. Both pseudotypes have comparable physical titers, but infectious titers with the RRV pseudotype are lower than with VSV-G. Incorporation of SFV glycoproteins into lentivirus vector is less efficient, leading to decreased physical and infectious titers. The transduction rates with VSV-G-, RRV-, and SFV-pseudotyped lentivirus vectors into adherent cell lines can be significantly increased by using a combination of Polybrene and plates coated with CH-296 recombinant fibronectin fragments. Together, our data suggest that RRV and SFV glycoproteins might be suitable as alternatives to VSV-G for pseudotyping lentivirus vectors.
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12

Tolah, Ahmed Majdi K., Sayed S. Sohrab, Khaled Majdi K. Tolah, Ahmed M. Hassan, Sherif A. El-Kafrawy, and Esam I. Azhar. "Evaluation of a Pseudovirus Neutralization Assay for SARS-CoV-2 and Correlation with Live Virus-Based Micro Neutralization Assay." Diagnostics 11, no. 6 (May 30, 2021): 994. http://dx.doi.org/10.3390/diagnostics11060994.

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Анотація:
The unusual cases of pneumonia outbreak were reported from Wuhan city in late December 2019. Serological testing provides a powerful tool for the identification of prior infection and for epidemiological studies. Pseudotype virus neutralization assays are widely used for many viruses and applications in the fields of serology. The accuracy of pseudotype neutralizing assay allows for its use in low biosafety lab and provides a safe and effective alternative to the use of wild-type viruses. In this study, we evaluated the performance of this assay compared to the standard microneutralization assay as a reference. The lentiviral pseudotype particles were generated harboring the Spike gene of SARS-CoV-2. The generated pseudotype particles assay was used to evaluate the activity of neutralizing antibodies in 300 human serum samples from a COVID-19 sero-epidemiological study. Testing of these samples resulted in 55 positive samples and 245 negative samples by pseudotype viral particles assay while microneutralization assay resulted in 64 positive and 236 negative by MN assay. Compared to the MN, the pseudotyped viral particles assay showed a sensitivity of 85.94% and a specificity of 100%. Based on the data generated from this study, the pseudotype-based neutralization assay showed a reliable performance for the detection of neutralizing antibodies against SARS-CoV-2 and can be used safely and efficiently as a diagnostic tool in a biosafety level 2 laboratory.
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13

Flint, Mike, Carine Logvinoff, Charles M. Rice, and Jane A. McKeating. "Characterization of Infectious Retroviral Pseudotype Particles Bearing Hepatitis C Virus Glycoproteins." Journal of Virology 78, no. 13 (July 1, 2004): 6875–82. http://dx.doi.org/10.1128/jvi.78.13.6875-6882.2004.

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Анотація:
ABSTRACT The recent development of infectious retroviral pseudotypes bearing hepatitis C virus (HCV) glycoproteins represents an opportunity to study the functionally active form of the HCV E1 and E2 glycoproteins. In the culture supernatant of cells producing HCV retroviral pseudotypes, the majority of E2 was not associated with infectious particles and failed to sediment on sucrose gradients. The E2 that was incorporated into infectious particles appeared as a triplet of diffuse bands at 60, 70, and 90 kDa. Similarly, three major forms of E1 were incorporated into the pseudotype particles, migrating at 33, 31, and 25 kDa. Endoglycosidase H (endo-H) treatment of particles demonstrated that the incorporated E1 was partially or completely sensitive to digestion. In contrast, the majority of the incorporated E2 was endo-H resistant. Purified pseudotype particles were found to contain both disulfide-linked aggregates and nonaggregated E1 and E2. HCV pseudotypes generated from cells expressing E1E2p7 showed similar heterogeneity in the incorporated glycoproteins and were of comparable infectivity to those generated by expression of E1E2. Our results demonstrate the heterogenous nature of E1 and E2 incorporated into retroviral pseudotypes and highlight the difficulty in identifying forms of the HCV glycoproteins that initiate infection.
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14

Kaname, Yuuki, Hideki Tani, Chikako Kataoka, Mai Shiokawa, Shuhei Taguwa, Takayuki Abe, Kohji Moriishi, Taroh Kinoshita, and Yoshiharu Matsuura. "Acquisition of Complement Resistance through Incorporation of CD55/Decay-Accelerating Factor into Viral Particles Bearing Baculovirus GP64." Journal of Virology 84, no. 7 (January 13, 2010): 3210–19. http://dx.doi.org/10.1128/jvi.02519-09.

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Анотація:
ABSTRACT A major obstacle to gene transduction by viral vectors is inactivation by human complement in vivo. One way to overcome this is to incorporate complement regulatory proteins, such as CD55/decay accelerating factor (DAF), into viral particles. Lentivirus vectors pseudotyped with the baculovirus envelope protein GP64 have been shown to acquire more potent resistance to serum inactivation and longer transgene expression than those pseudotyped with the vesicular stomatitis virus (VSV) envelope protein G. However, the molecular mechanisms underlying resistance to serum inactivation in pseudotype particles bearing the GP64 have not been precisely elucidated. In this study, we generated pseudotype and recombinant VSVs bearing the GP64. Recombinant VSVs generated in human cell lines exhibited the incorporation of human DAF in viral particles and were resistant to serum inactivation, whereas those generated in insect cells exhibited no incorporation of human DAF and were sensitive to complement inactivation. The GP64 and human DAF were detected on the detergent-resistant membrane and were coprecipitated by immunoprecipitation analysis. A pseudotype VSV bearing GP64 produced in human DAF knockdown cells reduced resistance to serum inactivation. In contrast, recombinant baculoviruses generated in insect cells expressing human DAF or carrying the human DAF gene exhibited resistance to complement inactivation. These results suggest that the incorporation of human DAF into viral particles by interacting with baculovirus GP64 is involved in the acquisition of resistance to serum inactivation.
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15

Del Rosario, Joanne Marie M., Kelly A. S. da Costa, Benedikt Asbach, Francesca Ferrara, Matteo Ferrari, David A. Wells, Gurdip Singh Mann, et al. "Exploiting Pan Influenza A and Pan Influenza B Pseudotype Libraries for Efficient Vaccine Antigen Selection." Vaccines 9, no. 7 (July 5, 2021): 741. http://dx.doi.org/10.3390/vaccines9070741.

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Анотація:
We developed an influenza hemagglutinin (HA) pseudotype library encompassing Influenza A subtypes HA1-18 and Influenza B subtypes (both lineages) to be employed in influenza pseudotype microneutralization (pMN) assays. The pMN is highly sensitive and specific for detecting virus-specific neutralizing antibodies against influenza viruses and can be used to assess antibody functionality in vitro. Here we show the production of these viral HA pseudotypes and their employment as substitutes for wildtype viruses in influenza neutralization assays. We demonstrate their utility in detecting serum responses to vaccination with the ability to evaluate cross-subtype neutralizing responses elicited by specific vaccinating antigens. Our findings may inform further preclinical studies involving immunization dosing regimens in mice and may help in the creation and selection of better antigens for vaccine design. These HA pseudotypes can be harnessed to meet strategic objectives that contribute to the strengthening of global influenza surveillance, expansion of seasonal influenza prevention and control policies, and strengthening pandemic preparedness and response.
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16

Hyseni, Inesa, Eleonora Molesti, Linda Benincasa, Pietro Piu, Elisa Casa, Nigel J. Temperton, Alessandro Manenti, and Emanuele Montomoli. "Characterisation of SARS-CoV-2 Lentiviral Pseudotypes and Correlation between Pseudotype-Based Neutralisation Assays and Live Virus-Based Micro Neutralisation Assays." Viruses 12, no. 9 (September 10, 2020): 1011. http://dx.doi.org/10.3390/v12091011.

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Анотація:
The recent outbreak of a novel Coronavirus (SARS-CoV-2) and its rapid spread across the continents has generated an urgent need for assays to detect the neutralising activity of human sera or human monoclonal antibodies against SARS-CoV-2 spike protein and to evaluate the serological immunity in humans. Since the accessibility of live virus microneutralisation (MN) assays with SARS-CoV-2 is limited and requires enhanced bio-containment, the approach based on “pseudotyping” can be considered a useful complement to other serological assays. After fully characterising lentiviral pseudotypes bearing the SARS-CoV-2 spike protein, we employed them in pseudotype-based neutralisation assays in order to profile the neutralising activity of human serum samples from an Italian sero-epidemiological study. The results obtained with pseudotype-based neutralisation assays mirrored those obtained when the same panel of sera was tested against the wild type virus, showing an evident convergence of the pseudotype-based neutralisation and MN results. The overall results lead to the conclusion that the pseudotype-based neutralisation assay is a valid alternative to using the wild-type strain, and although this system needs to be optimised and standardised, it can not only complement the classical serological methods, but also allows serological assessments to be made when other methods cannot be employed, especially in a human pandemic context.
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17

Halbert, Christine L., Elizabeth A. Rutledge, James M. Allen, David W. Russell, and A. Dusty Miller. "Repeat Transduction in the Mouse Lung by Using Adeno-Associated Virus Vectors with Different Serotypes." Journal of Virology 74, no. 3 (February 1, 2000): 1524–32. http://dx.doi.org/10.1128/jvi.74.3.1524-1532.2000.

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Анотація:
ABSTRACT Vectors derived from adeno-associated virus type 2 (AAV2) promote gene transfer and expression in the lung; however, we have found that while gene expression can persist for at least 8 months in mice, it was reduced dramatically in rabbits over a period of 2 months. The efficiency and persistence of AAV2-mediated gene expression in the human lung have yet to be determined, but it seems likely that readministration will be necessary over the lifetime of an individual. Unfortunately, we have found that transduction by a second administration of an AAV2 vector is blocked, presumably due to neutralizing antibodies generated in response to the primary vector exposure. Here, we have explored the use of AAV2 vectors pseudotyped with capsid proteins from AAV serotypes 2, 3, and 6 for readministration in the mouse lung. We found that an AAV6 vector transduced airway epithelial and alveolar cells in the lung at rates that were at least as high as those of AAV2 pseudotype vectors, while transduction rates mediated by AAV3 were much lower. AAV6 pseudotype vector transduction was unaffected by prior administration of an AAV2 or AAV3 vector, and transduction by an AAV2 pseudotype vector was unaffected by prior AAV6 vector administration, showing that cross-reactive neutralizing antibodies against AAV2 and AAV6 are not generated in mice. Interestingly, while prior administration of an AAV2 vector completely blocked transduction by a second AAV2 pseudotype vector, prior administration of an AAV6 vector only partially inhibited transduction by a second administration of an AAV6 pseudotype vector. Analysis of sera obtained from mice and humans showed that AAV6 is less immunogenic than AAV2, which helps explain this finding. These results support the development of AAV6 vectors for lung gene therapy both alone and in combination with AAV2 vectors.
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18

Zhang, Jie, Glenn Randall, Adrian Higginbottom, Peter Monk, Charles M. Rice, and Jane A. McKeating. "CD81 Is Required for Hepatitis C Virus Glycoprotein-Mediated Viral Infection." Journal of Virology 78, no. 3 (February 1, 2004): 1448–55. http://dx.doi.org/10.1128/jvi.78.3.1448-1455.2004.

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ABSTRACT CD81 has been described as a putative receptor for hepatitis C virus (HCV); however, its role in HCV cell entry has not been characterized due to the lack of an efficient cell culture system. We have examined the role of CD81 in HCV glycoprotein-dependent entry by using a recently developed retroviral pseudotyping system. Human immunodeficiency virus (HIV) pseudotypes bearing HCV E1E2 glycoproteins show a restricted tropism for human liver cell lines. Although all of the permissive cell lines express CD81, CD81 expression alone is not sufficient to allow viral entry. CD81 is required for HIV-HCV pseudotype infection since (i) a monoclonal antibody specific for CD81 inhibited infection of susceptible target cells and (ii) silencing of CD81 expression in Huh-7.5 hepatoma cells by small interfering RNAs inhibited HIV-HCV pseudotype infection. Furthermore, expression of CD81 in human liver cells that were previously resistant to infection, HepG2 and HH29, conferred permissivity of HCV pseudotype infection. The characterization of chimeric CD9/CD81 molecules confirmed that the large extracellular loop of CD81 is a determinant for viral entry. These data suggest a functional role for CD81 as a coreceptor for HCV glycoprotein-dependent viral cell entry.
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19

Sung, Vicky M. H., and Michael M. C. Lai. "Murine Retroviral Pseudotype Virus Containing Hepatitis B Virus Large and Small Surface Antigens Confers Specific Tropism for Primary Human Hepatocytes: a Potential Liver-Specific Targeting System." Journal of Virology 76, no. 2 (January 15, 2002): 912–17. http://dx.doi.org/10.1128/jvi.76.2.912-917.2002.

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ABSTRACT We have developed a system for producing murine leukemia virus (MLV) pseudotyped with human hepatitis B virus (HBV) large (L) and small (S) surface antigens (HBsAg) for targeting primary human hepatocytes. Using the MLV(HBV) pseudotype virus containing a β-galactosidase reporter gene, we demonstrated that this pseudotype virus exhibits strict tropism for primary human hepatocytes, similar to the natural target cell specificity of HBV. It does not infect any of the established tissue culture cell lines, including human hepatoma cell lines (HepG2 and Huh-7), or rat primary hepatocytes. The infectivity of MLV(HBV) for human hepatocytes was inhibited by anti-HBs antibody. The L form of HBsAg was both necessary and sufficient for virus infectivity, but the presence of both L and S forms enhanced the surface expression of HBsAg and thus increased virus production. The middle form of HBsAg was not necessary. This pseudotype virus bypasses the requirement for the liver-specific transcription factors for HBV replication, enabling direct study of HBV tissue tropism conferred by the viral envelope proteins. This virus also offers a potential liver-specific targeting system for gene therapy.
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20

Arai, Tohru, Kazuyuki Matsumoto, Kanako Saitoh, Motoyasu Ui, Taiji Ito, Masao Murakami, Yumi Kanegae, et al. "A New System for Stringent, High-Titer Vesicular Stomatitis Virus G Protein-Pseudotyped Retrovirus Vector Induction by Introduction of Cre Recombinase into Stable Prepackaging Cell Lines." Journal of Virology 72, no. 2 (February 1, 1998): 1115–21. http://dx.doi.org/10.1128/jvi.72.2.1115-1121.1998.

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ABSTRACT We report here on stable prepackaging cell lines which can be converted into packaging cell lines for high-titer vesicular stomatitis virus G protein (VSV-G)-pseudotyped retrovirus vectors by the introduction of Cre recombinase-expressing adenovirus. The generated prepackaging cell lines constitutively express the gag-polgenes and contain an inducible transcriptional unit for the VSV-G gene. From this unit, the introduced Cre recombinase excised both a neomycin resistance (Neor) gene and a poly(A) signal flanked by a tandem pair of loxP sequences and induced transcription of the VSV-G gene from the same promoter as had been used for Neor expression. By inserting an mRNA-destabilizing signal into the 3′ untranslated region of the Neor gene to reduce the amount of Neor transcript, we were able efficiently to select the clones capable of inducing VSV-G at high levels. Without the introduction of Cre recombinase, these cell lines produce neither VSV-G nor any detectable infectious virus at all, even after the transduction of a murine leukemia virus-based retrovirus vector encoding β-galactosidase. They reproducibly produced high-titer virus stocks of VSV-G-pseudotyped retrovirus (1.0 × 106 infectious units/ml) from 3 days after the introduction of Cre recombinase. We also present evidence that VSV-G-producing cells are still fully susceptible to transduction by VSV-G pseudotypes. However, in this vector-producing system, which regulates VSV-G pseudotype production in an all-or-none manner, the integration of vector DNA into packaging cell lines would be minimized. We further show that heparin significantly inhibits retransduction of VSV-G pseudotypes in the culture fluids of packaging cell lines, leading to a two- to fourfold increase in the yield of the pseudotypes after induction. This vector-producing system was very stable and should be advantageous in human gene therapy.
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21

Saha, Manujendra N., Atsushi Tanaka, Atsushi Jinno-Oue, Nobuaki Shimizu, Kazushi Tamura, Masahiko Shinagawa, Joe Chiba, and Hiroo Hoshino. "Formation of Vesicular Stomatitis Virus Pseudotypes Bearing Surface Proteins of Hepatitis B Virus." Journal of Virology 79, no. 19 (October 1, 2005): 12566–74. http://dx.doi.org/10.1128/jvi.79.19.12566-12574.2005.

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ABSTRACT It has been difficult to propagate and titrate hepatitis B virus (HBV) in tissue culture. We examined whether vesicular stomatitis virus (VSV) pseudotypes bearing HBV surface (HBs) proteins infectious for human cell lines could be prepared. For this, expression plasmids for three surface proteins, L, M, and S, of HBV were made. 293T cells were then transfected with these plasmids either individually or in different combinations. 293T cells expressing HBs proteins were infected with VSVΔG*-G, a recombinant VSV expressing green fluorescent protein (GFP), to make VSV pseudotypes. Culture supernatants together with cells were harvested and sonicated for a short time. The infectivities of freshly harvested supernatants were determined by quantifying the number of cells expressing GFP after neutralization with anti-VSV serum and mouse monoclonal antibodies (MAbs) against HBs protein. Among 14 cell lines tested for susceptibility to HBV pseudotype samples, HepG2, JHH-7, and 293T cells were judged to be the most susceptible. Namely, the infectious units (IU) of the culture supernatant samples neutralized with anti-VSV in the absence and presence of anti-HBs S MAbs and titrated on HepG2 cells ranged from 1,000 to 4,000 IU/ml and 200 to 400 IU/ml, respectively, suggesting the presence of VSVΔG*(HBV) pseudotypes. This infectivity was inhibited by treatment with lactoferrin or dextran sulfate. Pretreatment of the cells with trypsin or tunicamycin inhibited plating of the pseudotype samples. The HBV pseudotypes can be used to analyze early steps of HBV infection, including the entry mechanism of HBV.
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22

Su, RuiJun, Rency L. Rosales, Martin Lochelt, and Neil C. Josephson. "Transduction of Primate Cells with Feline Foamy Virus Envelope Pseudotyped Prototype Foamy Virus Vectors." Blood 104, no. 11 (November 16, 2004): 5276. http://dx.doi.org/10.1182/blood.v104.11.5276.5276.

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Abstract Because of their genetic and biological similarity to humans, non-human primates are the best pre-clinical models for testing the efficacy and safety of gene therapy systems. However, the presence of endogenous simian foamy virus infection in nearly all non-human primates kept in captivity complicates foamy virus (FV) vector stem cell transduction studies in these animals. A major concern is that repopulating cells exposed to FV vector stocks will elicit an immune response in non-human primate hosts. Though human serum does not inactivate prototype foamy virus (PFV) vectors, a one hour incubation of PFV vector stock in the presence of serum samples from Papio Cynophalus (baboon), Macaca Mulatta (rhesus macaque), or Macaca Fasicularis (long-tailed macaque) results in a 75–100% drop in titer. To overcome this serum mediated inactivation we sought to pseudotype PFV vectors in the feline foamy virus (FFV) envelope. The wild-type envelope from the FUV strain of FFV does not pseudotype our PFV vectors. Therefore we generated chimeras with regions of both the FFV and PFV envelope. By substituting portions of the FFV envelope leader peptide sequence and membrane spanning domain with corresponding PFV envelope regions we generated chimeric envelopes capable of high titer (105–106 FFU/ml) PFV vector production. Serum samples from Macaca Mulatta produced less inactivation of the FFV pseudotyped than the PFV pseudotyped vectors. Furthermore, both the PFV and FFV pseudotyped vectors demonstrated efficient transduction of baboon mesenchymal stem cells (27–43%) and baboon embryonic stem cells (37–40%). However, the FFV pseudotyped vectors transduced both human and baboon CD34+ cells less efficiently than the PFV pseudotyped vectors. We plan to test PFV vectors pseudotyped by other FV envelopes for inactivation by primate serum, and for their ability to transduce primate hematopoietic cells.
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23

Basu, Arnab, Aster Beyene, Keith Meyer, and Ranjit Ray. "The Hypervariable Region 1 of the E2 Glycoprotein of Hepatitis C Virus Binds to Glycosaminoglycans, but This Binding Does Not Lead to Infection in a Pseudotype System." Journal of Virology 78, no. 9 (May 1, 2004): 4478–86. http://dx.doi.org/10.1128/jvi.78.9.4478-4486.2004.

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ABSTRACT The hypervariable region 1 (HVR1) of hepatitis C virus (HCV) E2 envelope glycoprotein is a 27-amino-acid sequence located at its N terminus. In this study, we investigated the functional role of HVR1 for interaction with the mammalian cell surface. The C-terminal truncated E2 glycoprotein was appended to a transmembrane domain and cytoplasmic tail of vesicular stomatitis virus (VSV) G protein for generation of the chimeric E2-G gene construct. A deletion of the HVR1 sequence from E2 was created for the construction of E2ΔHVR1-G. Pseudotype virus, generated separately by infection of a stable cell line expressing E2-G or E2ΔHVR1-G with a temperature-sensitive mutant of VSV (VSVts045), displayed unique functional properties compared to VSVts045 as a negative control. Virus generated from E2ΔHVR1-G had a reduced plaquing efficiency (∼50%) in HepG2 cells compared to that for the E2-G virus. Cells prior treated with pronase (0.5 U/ml) displayed a complete inhibition of infectivity of the E2ΔHVR1-G or E2-G pseudotypes, whereas heparinase I treatment (8 U/ml) of cells reduced 40% E2-G pseudotype virus titer only. E2ΔHVR1-G pseudotypes were not sensitive to heparin (6 to 50 μg/ml) as an inhibitor of plaque formation compared to the E2-G pseudotype virus. Although the HVR1 sequence itself does not match with the known heparin-binding domain, a synthetic peptide representing 27 amino acids of the E2 HVR1 displayed a strong affinity for heparin in an enzyme-linked immunosorbent assay. This binding was competitively inhibited by a peptide from the V3 loop of a human immunodeficiency virus glycoprotein subunit (gp120) known to bind with cell surface heparin. Taken together, our results suggest that the HVR1 of E2 glycoprotein binds to the cell surface proteoglycans and may facilitate virus-host interaction for replication cycle of HCV.
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24

Kang, Yubin, Colleen S. Stein, Jason A. Heth, Patrick L. Sinn, Andrea K. Penisten, Patrick D. Staber, Kenneth L. Ratliff, et al. "In Vivo Gene Transfer Using a Nonprimate Lentiviral Vector Pseudotyped with Ross River Virus Glycoproteins." Journal of Virology 76, no. 18 (September 15, 2002): 9378–88. http://dx.doi.org/10.1128/jvi.76.18.9378-9388.2002.

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ABSTRACT Vectors derived from lentiviruses provide a promising gene delivery system. We examined the in vivo gene transfer efficiency and tissue or cell tropism of a feline immunodeficiency virus (FIV)-based lentiviral vector pseudotyped with the glycoproteins from Ross River Virus (RRV). RRV glycoproteins were efficiently incorporated into FIV virions, generating preparations of FIV vector, which after concentration attain titers up to 1.5 × 108 TU/ml. After systemic administration, RRV-pseudotyped FIV vectors (RRV/FIV) predominantly transduced the liver of recipient mice. Transduction efficiency in the liver with the RRV/FIV was ca. 20-fold higher than that achieved with the vesicular stomatitis virus G protein (VSV-G) pseudotype. Moreover, in comparison to VSV-G, the RRV glycoproteins caused less cytotoxicity, as determined from the levels of glutamic pyruvic transaminase and glutamic oxalacetic transaminase in serum. Although hepatocytes were the main liver cell type transduced, nonhepatocytes (mainly Kupffer cells) were also transduced. The percentages of the transduced nonhepatocytes were comparable between RRV and VSV-G pseudotypes and did not correlate with the production of antibody against the transgene product. After injection into brain, RRV/FIV preferentially transduced neuroglial cells (astrocytes and oligodendrocytes). In contrast to the VSV-G protein that targets predominantly neurons, <10% of the brain cells transduced with the RRV pseudotyped vector were neurons. Finally, the gene transfer efficiencies of RRV/FIV after direct application to skeletal muscle or airway were also examined and, although transgene-expressing cells were detected, their proportions were low. Our data support the utility of RRV glycoprotein-pseudotyped FIV lentiviral vectors for hepatocyte- and neuroglia-related disease applications.
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25

Sampson, Alexander Thomas, Jonathan Heeney, Diego Cantoni, Matteo Ferrari, Maria Suau Sans, Charlotte George, Cecilia Di Genova, et al. "Coronavirus Pseudotypes for All Circulating Human Coronaviruses for Quantification of Cross-Neutralizing Antibody Responses." Viruses 13, no. 8 (August 10, 2021): 1579. http://dx.doi.org/10.3390/v13081579.

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The novel coronavirus SARS-CoV-2 is the seventh identified human coronavirus. Understanding the extent of pre-existing immunity induced by seropositivity to endemic seasonal coronaviruses and the impact of cross-reactivity on COVID-19 disease progression remains a key research question in immunity to SARS-CoV-2 and the immunopathology of COVID-2019 disease. This paper describes a panel of lentiviral pseudotypes bearing the spike (S) proteins for each of the seven human coronaviruses (HCoVs), generated under similar conditions optimized for high titre production allowing a high-throughput investigation of antibody neutralization breadth. Optimal production conditions and most readily available permissive target cell lines were determined for spike-mediated entry by each HCoV pseudotype: SARS-CoV-1, SARS-CoV-2 and HCoV-NL63 best transduced HEK293T/17 cells transfected with ACE2 and TMPRSS2, HCoV-229E and MERS-CoV preferentially entered HUH7 cells, and CHO cells were most permissive for the seasonal betacoronavirus HCoV-HKU1. Entry of ACE2 using pseudotypes was enhanced by ACE2 and TMPRSS2 expression in target cells, whilst TMPRSS2 transfection rendered HEK293T/17 cells permissive for HCoV-HKU1 and HCoV-OC43 entry. Additionally, pseudotype viruses were produced bearing additional coronavirus surface proteins, including the SARS-CoV-2 Envelope (E) and Membrane (M) proteins and HCoV-OC43/HCoV-HKU1 Haemagglutinin-Esterase (HE) proteins. This panel of lentiviral pseudotypes provides a safe, rapidly quantifiable and high-throughput tool for serological comparison of pan-coronavirus neutralizing responses; this can be used to elucidate antibody dynamics against individual coronaviruses and the effects of antibody cross-reactivity on clinical outcome following natural infection or vaccination.
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26

Crawford, Katharine H. D., Rachel Eguia, Adam S. Dingens, Andrea N. Loes, Keara D. Malone, Caitlin R. Wolf, Helen Y. Chu, et al. "Protocol and Reagents for Pseudotyping Lentiviral Particles with SARS-CoV-2 Spike Protein for Neutralization Assays." Viruses 12, no. 5 (May 6, 2020): 513. http://dx.doi.org/10.3390/v12050513.

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SARS-CoV-2 enters cells using its Spike protein, which is also the main target of neutralizing antibodies. Therefore, assays to measure how antibodies and sera affect Spike-mediated viral infection are important for studying immunity. Because SARS-CoV-2 is a biosafety-level-3 virus, one way to simplify such assays is to pseudotype biosafety-level-2 viral particles with Spike. Such pseudotyping has now been described for single-cycle lentiviral, retroviral, and vesicular stomatitis virus (VSV) particles, but the reagents and protocols are not widely available. Here, we detailed how to effectively pseudotype lentiviral particles with SARS-CoV-2 Spike and infect 293T cells engineered to express the SARS-CoV-2 receptor, ACE2. We also made all the key experimental reagents available in the BEI Resources repository of ATCC and the NIH. Furthermore, we demonstrated how these pseudotyped lentiviral particles could be used to measure the neutralizing activity of human sera or plasma against SARS-CoV-2 in convenient luciferase-based assays, thereby providing a valuable complement to ELISA-based methods that measure antibody binding rather than neutralization.
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27

Ito, Hiroshi, Shinji Watanabe, Ayato Takada, and Yoshihiro Kawaoka. "Ebola Virus Glycoprotein: Proteolytic Processing, Acylation, Cell Tropism, and Detection of Neutralizing Antibodies." Journal of Virology 75, no. 3 (February 1, 2001): 1576–80. http://dx.doi.org/10.1128/jvi.75.3.1576-1580.2001.

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ABSTRACT Using the vesicular stomatitis virus (VSV) pseudotype system, we studied the functional properties of the Ebola virus glycoprotein (GP). Amino acid substitutions at the GP cleavage site, which reduce glycoprotein cleavability and viral infectivity in some viruses, did not appreciably change the infectivity of VSV pseudotyped with GP. Likewise, removal of two acylated cysteine residues in the transmembrane region of GP showed no discernible effects on infectivity. Although most filoviruses are believed to target endothelial cells and hepatocytes preferentially, the GP-carrying VSV showed greater affinity for epithelial cells than for either of these cell types, indicating that Ebola virus GP does not necessarily have strong tropism toward endothelial cells and hepatocytes. Finally, when it was used to screen for neutralizing antibodies against Ebola virus GP, the VSV pseudotype system allowed us to detect strain-specific neutralizing activity that was inhibited by secretory GP (SGP). This finding provides evidence of shared neutralizing epitopes on GP and SGP molecules and indicates the potential of SGP to serve as a decoy for neutralizing antibodies.
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28

Zimmer, Gert, Samira Locher, Marianne Berger Rentsch, and Stefan J. Halbherr. "Pseudotyping of vesicular stomatitis virus with the envelope glycoproteins of highly pathogenic avian influenza viruses." Journal of General Virology 95, no. 8 (August 1, 2014): 1634–39. http://dx.doi.org/10.1099/vir.0.065201-0.

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Pseudotype viruses are useful for studying the envelope proteins of harmful viruses. This work describes the pseudotyping of vesicular stomatitis virus (VSV) with the envelope glycoproteins of highly pathogenic avian influenza viruses. VSV lacking the homotypic glycoprotein (G) gene (VSVΔG) was used to express haemagglutinin (HA), neuraminidase (NA) or the combination of both. Propagation-competent pseudotype viruses were only obtained when HA and NA were expressed from the same vector genome. Pseudotype viruses containing HA from different H5 clades were neutralized specifically by immune sera directed against the corresponding clade. Fast and sensitive reading of test results was achieved by vector-mediated expression of GFP. Pseudotype viruses expressing a mutant VSV matrix protein showed restricted spread in IFN-competent cells. This pseudotype system will facilitate the detection of neutralizing antibodies against virulent influenza viruses, circumventing the need for high-level biosafety containment.
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29

Westenberg, Marcel, Helen M. Soedling, Nisha Hirani, Linda J. Nicholson, Derek A. Mann, and Colin T. Dolphin. "Seamless replacement of Autographa californica multiple nucleopolyhedrovirus gp64 with each of five novel type II alphabaculovirus fusion sequences generates pseudotyped virus that fails to transduce mammalian cells." Journal of General Virology 93, no. 7 (July 1, 2012): 1583–90. http://dx.doi.org/10.1099/vir.0.041921-0.

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Autographa californica multiple nucleopolyhedrovirus (AcMNPV), a member of the type I alphabaculoviruses, is able to transduce and deliver a functional gene to a range of non-host cells, including many mammalian lines and primary cells, a property mediated by the envelope fusion protein GP64. AcMNPV is non-cytopathic and inherently replication deficient in non-host cells. As such, AcMNPV represents a possible new class of gene therapy vector with potential future clinical utility. Whilst not a problem for in vitro gene delivery, the broad tropism displayed for non-host cells is less desirable in a gene therapy vector. The fusion protein F of type II alphabaculoviruses can substitute functionally for GP64, and such pseudotyped viruses display a severely impaired capacity for non-host-cell transduction. Thus, surface decoration of such an F-pseudotyped AcMNPV with cell-binding ligands may restore transduction competence and generate vectors with desirable cell-targeting characteristics. By seamlessly swapping the native gp64 coding sequence with each of five sequences encoding different F proteins, a set of F-pseudotyped AcMNPV was generated. This report details their relative abilities both to functionally replace GP64 in viral growth and to transduce human Saos-2 and HeLa cells. All five supported viable infections in insect cell cultures and one, the Mamestra configurata NPV (MacoNPV) F pseudotype, could be amplified to titres close to those of native AcMNPV. In contrast, none was able to transduce the Saos-2 and HeLa cell lines. The robust support provided by MacoNPV F in virus production makes the corresponding pseudotype a viable scaffold to display surface ligands to direct selective mammalian cell targeting.
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30

Wright, Edward, Nigel J. Temperton, Denise A. Marston, Lorraine M. McElhinney, Anthony R. Fooks, and Robin A. Weiss. "Investigating antibody neutralization of lyssaviruses using lentiviral pseudotypes: a cross-species comparison." Journal of General Virology 89, no. 9 (September 1, 2008): 2204–13. http://dx.doi.org/10.1099/vir.0.2008/000349-0.

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Cross-neutralization between rabies virus (RABV) and two European bat lyssaviruses (EBLV-1 and -2) was analysed using lentiviral pseudotypes as antigen vectors. Glycoprotein (G-protein) cDNA from RABV challenge virus standard-11 (CVS-11) and EBLV-1 and -2 were cloned and co-expressed with human immunodeficiency virus (HIV) or murine leukemia virus (MLV) gag–pol and packageable green fluorescent protein (GFP) or luciferase reporter genes in human cells. The harvested lentiviral (HIV) vector infected over 40 % of baby hamster kidney (BHK) target cells, providing high-titre pseudotype stocks. Tests on blinded antibody-positive (n=15) and -negative (n=45) sera, predetermined by the fluorescent antibody virus neutralization (FAVN) test approved by the World Health Organization (WHO) and Office International des Epizooties (OIE), revealed that the CVS-11 pseudotype assay had 100 % concordance with FAVN and strongly correlated with neutralization titres (r 2=0.89). Cross-neutralization tests using sera from RABV-vaccinated humans and animals on pseudotypes with CVS-11, EBLV-1 and EBLV-2 envelopes showed that the relative neutralization titres correlated broadly with the degree of G-protein diversity. Pseudotypes have three major advantages over live-virus neutralization tests: (i) they can be handled in low-biohazard-level laboratories; (ii) the use of reporter genes such as GFP or β-galactosidase will allow the assay to be undertaken at low cost in laboratories worldwide; (iii) each assay requires <10 μl serum. This robust microassay will improve our understanding of the protective humoral immunity that current rabies vaccines confer against emerging lyssaviruses, and will be applicable to surveillance studies, thus helping to control the spread of rabies.
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31

Kitagawa, Yoshinori, Hideki Tani, Chang Kwang Limn, Tomoko M. Matsunaga, Kohji Moriishi, and Yoshiharu Matsuura. "Ligand-Directed Gene Targeting to Mammalian Cells by Pseudotype Baculoviruses." Journal of Virology 79, no. 6 (March 15, 2005): 3639–52. http://dx.doi.org/10.1128/jvi.79.6.3639-3652.2005.

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Анотація:
ABSTRACT The baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) can infect a variety of mammalian cells, as well as insect cells, facilitating its use as a viral vector for gene delivery into mammalian cells. Glycoprotein gp64, a major component of the budded AcMNPV envelope, is involved in viral entry into cells by receptor-mediated endocytosis and subsequent membrane fusion. We examined the potential production of pseudotype baculovirus particles transiently carrying ligands of interest in place of gp64 as a method of ligand-directed gene delivery into target cells. During amplification of a gp64-null pseudotype baculovirus carrying a green fluorescent protein gene in gp64-expressing insect cells, however, we observed the high-frequency appearance of a replication-competent virus incorporating the gp64 gene into the viral genome. To avoid generation of replication-competent revertants, we prepared pseudotype baculoviruses by transfection with recombinant bacmids without further amplification in the gp64-expressing cells. We constructed gp64-null recombinant bacmids carrying cDNAs encoding either vesicular stomatitis virus G protein (VSVG) or measles virus receptors (CD46 or SLAM). The VSVG pseudotype baculovirus efficiently transduced a reporter gene into a variety of mammalian cell lines, while CD46 and SLAM pseudotype baculoviruses allowed ligand-receptor-directed reporter gene transduction into target cells expressing measles virus envelope glycoproteins. Gene transduction mediated by the pseudotype baculoviruses could be inhibited by pretreatment with specific antibodies. These results indicate the possible application of pseudotype baculoviruses in ligand-directed gene delivery into target cells.
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32

Temperton, Nigel. "The Viral Pseudotype Unit: viral pseudotype R&D, dissemination and education." Future Virology 11, no. 2 (February 2016): 113–16. http://dx.doi.org/10.2217/fvl.15.109.

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33

Lasickienė, Rita, Alma Gedvilaite, Milda Norkiene, Vaida Simanaviciene, Indre Sezaite, Dovile Dekaminaviciute, Evelina Shikova, and Aurelija Zvirbliene. "The Use of Recombinant Pseudotype Virus-Like Particles Harbouring Inserted Target Antigen to Generate Antibodies against Cellular Marker p16INK4A." Scientific World Journal 2012 (2012): 1–8. http://dx.doi.org/10.1100/2012/263737.

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Анотація:
Protein engineering provides an opportunity to generate new immunogens with desired features. Previously, we have demonstrated that hamster polyomavirus major capsid protein VP1-derived virus-like particles (VLPs) are highly immunogenic and can be employed for the insertion of foreign epitopes at certain surface-exposed positions. In the current study, we have designed pseudotype VLPs consisting of an intact VP1 protein and VP2 protein fused with the target antigen—cellular marker p16INK4A—at its N terminus. Both proteins coexpressed in yeast were self-assembled to pseudotype VLPs harbouring the inserted antigen on the surface. The pseudotype VLPs were used for generation of antibodies against p16INK4Athat represents a potential biomarker for cells transformed by high-risk human papillomavirus (HPV). The pseudotype VLPs induced in immunized mice a strong immune response against the target antigen. The antisera raised against pseudotype VLPs showed specific immunostaining of p16INK4Aprotein in malignant cervical tissue. Spleen cells of the immunized mice were used to generate monoclonal antibodies against p16INK4Aprotein. The specificity of antibodies was proven by the immunostaining of HPV-transformed cells. In conclusion, the current study demonstrates the potential of pseudotype VLPs with inserted target antigen as a new type of immunogens to generate antibodies of high diagnostic value.
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34

Perez, Mar, Michiko Watanabe, Michael A. Whitt, and Juan Carlos de la Torre. "N-Terminal Domain of Borna Disease Virus G (p56) Protein Is Sufficient for Virus Receptor Recognition and Cell Entry." Journal of Virology 75, no. 15 (August 1, 2001): 7078–85. http://dx.doi.org/10.1128/jvi.75.15.7078-7085.2001.

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Анотація:
ABSTRACT Borna disease virus (BDV) surface glycoprotein (GP) (p56) has a predicted molecular mass of 56 kDa. Due to extensive posttranslational glycosylation the protein migrates as a polypeptide of 84 kDa (gp84). The processing of gp84 by the cellular protease furin generates gp43, which corresponds to the C-terminal part of gp84. Both gp84 and gp43 have been implicated in viral entry involving receptor-mediated endocytosis and pH-dependent fusion. We have investigated the domains of BDV p56 involved in virus entry. For this, we used a pseudotype approach based on a recently developed recombinant vesicular stomatitis virus (VSV) in which the gene for green fluorescent protein was substituted for the VSV G protein gene (VSVΔG*). Complementation of VSVΔG* with BDV p56 resulted in infectious VSVΔG* pseudotypes that contained both BDV gp84 and gp43. BDV-VSV chimeric GPs that contained the N-terminal 244 amino acids of BDV p56 and amino acids 421 to 511 of VSV G protein were efficiently incorporated into VSVΔG* particles, and the resulting pseudotype virions were neutralized by BDV-specific antiserum. These findings indicate that the N-terminal part of BDV p56 is sufficient for receptor recognition and virus entry.
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35

Meyer, Keith, Arnab Basu, Craig T. Przysiecki, L. Martin Lagging, Adrian M. Di Bisceglie, Anthony J. Conley, and Ranjit Ray. "Complement-Mediated Enhancement of Antibody Function for Neutralization of Pseudotype Virus Containing Hepatitis C Virus E2 Chimeric Glycoprotein." Journal of Virology 76, no. 5 (March 1, 2002): 2150–58. http://dx.doi.org/10.1128/jvi.76.5.2150-2158.2002.

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ABSTRACT We previously reported a number of features of hepatitis C virus (HCV) chimeric glycoproteins related to pseudotype virus entry into mammalian cells. In this study, pseudotype virus was neutralized by HCV E2 glycoprotein-specific antibodies and infected human sera. Neutralization (50% reduction of pseudotype virus plaque formation) was observed with two human immunoglobulin G1 monoclonal antibodies (MAbs) at concentrations of between 2.5 and 10 μg/ml. A hyperimmune rabbit antiserum to an E2 hypervariable region 1 (HVR1) mimotope also exhibited an HCV E2 pseudotype virus neutralization titer of ∼1/50. An E1 pseudotype virus used as a negative control was not neutralized to a significant level (<1/10) by these MAbs or rabbit antiserum to E2 HVR1. Since HCV probably has a lipid envelope, the role of complement in antibody-mediated virus neutralization was examined. Significant increases in the neutralization titers of the human MAbs (∼60- to 160-fold higher) and rabbit antiserum to HVR1 mimotopes (∼10-fold higher) were observed upon addition of guinea pig complement. Further, these studies suggested that complement activation occured primarily by the classical pathway, since a deficiency in the C4 component led to a significant decrease in the level of virus neutralization. This same decrease was not observed with factor B-deficient complement. We also determined that 9 of 56 HCV-infected patient sera (16%) had detectable pseudotype virus neutralization activity at serum dilutions of between 1/20 and 1/50 and that complement addition enhanced the neutralization activity of some of the HCV-infected human sera. Taken together, these results suggest that during infection, HCV E2 glycoprotein induces a weak neutralizing antibody response, that those antibodies can be measured in vitro by the surrogate pseudotype virus plaque reduction assay, and that neutralization function can be augmented by complement.
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36

Meyer, Keith, Malika Ait-Goughoulte, Zhen-Yong Keck, Steven Foung, and Ranjit Ray. "Antibody-Dependent Enhancement of Hepatitis C Virus Infection." Journal of Virology 82, no. 5 (December 19, 2007): 2140–49. http://dx.doi.org/10.1128/jvi.01867-07.

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ABSTRACT Hepatitis C virus (HCV) often causes a persistent infection associated with hypergammaglobulinemia, high levels of antiviral antibody and circulating immune complexes, and immune complex disease. We previously reported that only a limited neutralizing activity to vesicular stomatitis virus or HCV pseudotype is generated in animals immunized with recombinant HCV envelope proteins and chronically infected HCV patient sera. Interestingly, when some of these neutralizing sera were diluted into a range of concentrations below those that reduced virus plaque number, an increase in pseudotype plaque formation was observed. Purified HCV E2-specific human monoclonal antibodies were used to further verify the specificity of this enhancement, and one- to twofold increases were apparent on permissive Huh-7 cells. The enhancement of HCV pseudotype titer could be inhibited by the addition of a Fc-specific anti-human immunoglobulin G Fab fragment to the virus-antibody mixture prior to infection. Treatment of cells with antibody to Fc receptor I (FcRI) or FcRII, but not FcRIII, also led to an inhibition of pseudotype titer enhancement in an additive manner. Human lymphoblastoid cell line (Raji), a poor host for HCV pseudotype infection, exhibited a four- to sixfold enhancement of pseudotype-mediated cell death upon incubation with antibody at nonneutralizing concentrations. A similar enhancement of cell culture-grown HCV infectivity by a human monoclonal antibody was also observed. Taken together, antibodies to viral epitopes enhancing HCV infection need to be taken into consideration for pathogenesis and in the development of an effective vaccine.
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37

Rothstein, L., JH Pierce, V. Klassen, and JS Greenberger. "Amphotropic retrovirus vector transfer of the v-ras oncogene to human hematopoietic and stromal cells in continuous bone marrow cultures." Blood 65, no. 3 (March 1, 1985): 744–52. http://dx.doi.org/10.1182/blood.v65.3.744.744.

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Abstract Human continuous bone marrow cultures were established from intraoperative marrow specimens and infected with amphotropic murine leukemia virus (Am-MuLV) pseudotypes of Kirsten or Harvey murine sarcoma virus, and the biologic effects were compared with mouse continuous bone marrow cultures. Cultures were tested for production of total nonadherent granulocytes and granulocyte-macrophage progenitor cells (GM-CFUc); virus replication by supernatant reverse transcriptase activity; percentage of adherent and nonadherent cells and GM-CFUc that released virus by infectious center assay; and for synthesis of Harvey ras p21 protein. High-efficiency, stable Am-MuLV infection of over 90% of human marrow-culture nonadherent and adherent cells and both seven- and 14-day GM-CFUc were detected as Kirsten or Harvey pseudotype virus release by infectious center assay. Synthesis of Harvey ras p21 was detected in the adherent and nonadherent cell populations of human as well as mouse continuous marrow cultures infected with Kirsten or Harvey pseudotype virus. In contrast to data with mouse cultures, cumulative production of GM-CFUc and differentiated granulocytes in human cultures was not detectably altered by Harvey or Kirsten virus infection, and all cultures ceased to produce hematopoietic cells by 20 weeks. Of 54 virus-infected cultures in ten separate experiments, 13 produced a second peak of nonadherent cells (greater than 10(5) per flask) after 20 weeks, significantly more frequently than did control uninfected cultures (one of 32). When subcultured, these harvests produced permanent Epstein-Barr virus (EBV)-transformed pre-B cell lines that released the original inoculating pseudotype virus. Thus, Am- MuLV is a potentially valuable vector for inserting genetic sequences by recombinant techniques into human hematopoietic and stromal cells in culture; however, activation of EBV may be a significant complication.
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38

Rothstein, L., JH Pierce, V. Klassen, and JS Greenberger. "Amphotropic retrovirus vector transfer of the v-ras oncogene to human hematopoietic and stromal cells in continuous bone marrow cultures." Blood 65, no. 3 (March 1, 1985): 744–52. http://dx.doi.org/10.1182/blood.v65.3.744.bloodjournal653744.

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Анотація:
Human continuous bone marrow cultures were established from intraoperative marrow specimens and infected with amphotropic murine leukemia virus (Am-MuLV) pseudotypes of Kirsten or Harvey murine sarcoma virus, and the biologic effects were compared with mouse continuous bone marrow cultures. Cultures were tested for production of total nonadherent granulocytes and granulocyte-macrophage progenitor cells (GM-CFUc); virus replication by supernatant reverse transcriptase activity; percentage of adherent and nonadherent cells and GM-CFUc that released virus by infectious center assay; and for synthesis of Harvey ras p21 protein. High-efficiency, stable Am-MuLV infection of over 90% of human marrow-culture nonadherent and adherent cells and both seven- and 14-day GM-CFUc were detected as Kirsten or Harvey pseudotype virus release by infectious center assay. Synthesis of Harvey ras p21 was detected in the adherent and nonadherent cell populations of human as well as mouse continuous marrow cultures infected with Kirsten or Harvey pseudotype virus. In contrast to data with mouse cultures, cumulative production of GM-CFUc and differentiated granulocytes in human cultures was not detectably altered by Harvey or Kirsten virus infection, and all cultures ceased to produce hematopoietic cells by 20 weeks. Of 54 virus-infected cultures in ten separate experiments, 13 produced a second peak of nonadherent cells (greater than 10(5) per flask) after 20 weeks, significantly more frequently than did control uninfected cultures (one of 32). When subcultured, these harvests produced permanent Epstein-Barr virus (EBV)-transformed pre-B cell lines that released the original inoculating pseudotype virus. Thus, Am- MuLV is a potentially valuable vector for inserting genetic sequences by recombinant techniques into human hematopoietic and stromal cells in culture; however, activation of EBV may be a significant complication.
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39

Stitz, Jörn, Christian J. Buchholz, and Klaus Cichutek. "MLV-derived retroviral pseudotype vectors." Gene Therapy and Regulation 1, no. 2 (August 15, 2000): 177–92. http://dx.doi.org/10.1163/156855800744601.

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40

Miletic, Hrvoje, Michael Bruns, Konstantinos Tsiakas, Birgit Vogt, Roya Rezai, Christopher Baum, Klaus Kühlke, et al. "Retroviral Vectors Pseudotyped with Lymphocytic Choriomeningitis Virus." Journal of Virology 73, no. 7 (July 1, 1999): 6114–16. http://dx.doi.org/10.1128/jvi.73.7.6114-6116.1999.

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ABSTRACT Pseudotyping can improve retroviral vector stability and transduction efficiency. Here, we describe a novel pseudotype of murine leukemia virus packaged with lymphocytic choriomeningitis virus (LCMV). This pseudotype was stable during ultracentrifugation and infected several cell lines from different species. Moreover, LCMV glycoproteins were not cell toxic.
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41

Schwegmann-Weßels, Christel, Jörg Glende, Xiaofeng Ren, Xiuxia Qu, Hongkui Deng, Luis Enjuanes, and Georg Herrler. "Comparison of vesicular stomatitis virus pseudotyped with the S proteins from a porcine and a human coronavirus." Journal of General Virology 90, no. 7 (July 1, 2009): 1724–29. http://dx.doi.org/10.1099/vir.0.009704-0.

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The surface proteins S of severe acute respiratory syndrome coronavirus (SARS-CoV) and transmissible gastroenteritis virus (TGEV) were compared for their ability to mediate infection of viral pseudotypes based on vesicular stomatitis virus (VSV). The cell tropism of the respective pseudotypes corresponded to the tropism of the viruses from which the S protein was derived. Higher infectivity values were obtained with the SARS-CoV S protein than with the TGEV S protein. Differences were observed with respect to the importance of the cytoplasmic tail and the membrane anchor of the S proteins. In the case of the SARS-CoV S protein, truncation of the cytoplasmic tail resulted in increased infectivity. For the TGEV S protein, the inactivation of an intracellular retention signal in the cytoplasmic tail was required. Exchange of the membrane anchor of the S proteins led to a low infection efficiency. Our results indicate that related glycoproteins may show substantial differences in their ability to mediate pseudotype infection.
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42

Kiem, Hans-Peter, Scott Heyward, Aaron Winkler, Jennifer Potter, James M. Allen, A. Dusty Miller, and Robert G. Andrews. "Gene Transfer into Marrow Repopulating Cells: Comparison Between Amphotropic and Gibbon Ape Leukemia Virus Pseudotyped Retroviral Vectors in a Competitive Repopulation Assay in Baboons." Blood 90, no. 11 (December 1, 1997): 4638–45. http://dx.doi.org/10.1182/blood.v90.11.4638.

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Анотація:
Abstract Many diseases might be treated by gene therapy targeted to the hematopoietic system, but low rates of gene transfer achieved in humans and large animals have limited the application of this technique. We have developed a competitive hematopoietic repopulation assay in baboons to evaluate methods for improving gene transfer and have used this method to compare gene transfer rates for retroviral vectors having an envelope protein (pseudotype) from amphotropic murine retrovirus with similar vectors having an envelope protein derived from gibbon ape leukemia virus (GALV). We hypothesized that vectors with a GALV pseudotype might perform better based on our previous work with cultured human hematopoietic cells. CD34+ marrow cells from each of four untreated baboons were divided into two equal portions that were cocultivated for 48 hours with packaging cells producing equivalent titers of either amphotropic or GALV pseudotyped vectors containing the neo gene. The vectors contained small sequence differences to allow differentiation of cells genetically marked by the different vectors. Nonadherent and adherent cells from the cultures were infused into animals after they received a myeloablative dose of total body irradiation. Polymerase chain reaction (PCR) analysis for neo gene-specific sequences in colony-forming unit–granulocyte-macrophage from cell populations used for transplant showed gene transfer rates of 2.7%, 7.1%, <15%, and 3.9% with the amphotropic vectors and 7.1%, 11.3%, <15%, and 26.4% with the GALV pseudotyped vector. PCR analysis of peripheral blood and marrow cells after engraftment showed the neo gene to be present in all four animals analyzed at levels between 0.1% and 5%. Overall gene transfer efficiency was higher with the GALVpseudotyped vector than with the amphotropic vectors. Southern blot analysis in one animal confirmed a gene transfer efficiency of between 1% and 5%. The higher gene transfer efficiency with the GALV-pseudotyped vector correlated with higher levels of GALV receptor RNA compared with the amphotropic receptor in CD34+ hematopoietic cells. These results show that GALV-pseudotyped vectors are capable of transducing baboon marrow repopulating cells and may allow more efficient gene transfer rates for human gene therapy directed at hematopoietic cells. In addition, our data show considerable differences in gene transfer efficiency between individual baboons, suggesting that a competitive repopulation assay will be critical for evaluation of methods designed to improve gene transfer into hematopoietic stem cells.
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43

Kiem, Hans-Peter, Scott Heyward, Aaron Winkler, Jennifer Potter, James M. Allen, A. Dusty Miller, and Robert G. Andrews. "Gene Transfer into Marrow Repopulating Cells: Comparison Between Amphotropic and Gibbon Ape Leukemia Virus Pseudotyped Retroviral Vectors in a Competitive Repopulation Assay in Baboons." Blood 90, no. 11 (December 1, 1997): 4638–45. http://dx.doi.org/10.1182/blood.v90.11.4638.4638_4638_4645.

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Анотація:
Many diseases might be treated by gene therapy targeted to the hematopoietic system, but low rates of gene transfer achieved in humans and large animals have limited the application of this technique. We have developed a competitive hematopoietic repopulation assay in baboons to evaluate methods for improving gene transfer and have used this method to compare gene transfer rates for retroviral vectors having an envelope protein (pseudotype) from amphotropic murine retrovirus with similar vectors having an envelope protein derived from gibbon ape leukemia virus (GALV). We hypothesized that vectors with a GALV pseudotype might perform better based on our previous work with cultured human hematopoietic cells. CD34+ marrow cells from each of four untreated baboons were divided into two equal portions that were cocultivated for 48 hours with packaging cells producing equivalent titers of either amphotropic or GALV pseudotyped vectors containing the neo gene. The vectors contained small sequence differences to allow differentiation of cells genetically marked by the different vectors. Nonadherent and adherent cells from the cultures were infused into animals after they received a myeloablative dose of total body irradiation. Polymerase chain reaction (PCR) analysis for neo gene-specific sequences in colony-forming unit–granulocyte-macrophage from cell populations used for transplant showed gene transfer rates of 2.7%, 7.1%, <15%, and 3.9% with the amphotropic vectors and 7.1%, 11.3%, <15%, and 26.4% with the GALV pseudotyped vector. PCR analysis of peripheral blood and marrow cells after engraftment showed the neo gene to be present in all four animals analyzed at levels between 0.1% and 5%. Overall gene transfer efficiency was higher with the GALVpseudotyped vector than with the amphotropic vectors. Southern blot analysis in one animal confirmed a gene transfer efficiency of between 1% and 5%. The higher gene transfer efficiency with the GALV-pseudotyped vector correlated with higher levels of GALV receptor RNA compared with the amphotropic receptor in CD34+ hematopoietic cells. These results show that GALV-pseudotyped vectors are capable of transducing baboon marrow repopulating cells and may allow more efficient gene transfer rates for human gene therapy directed at hematopoietic cells. In addition, our data show considerable differences in gene transfer efficiency between individual baboons, suggesting that a competitive repopulation assay will be critical for evaluation of methods designed to improve gene transfer into hematopoietic stem cells.
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44

Christodoulopoulos, Ilias, and Paula M. Cannon. "Sequences in the Cytoplasmic Tail of the Gibbon Ape Leukemia Virus Envelope Protein That Prevent Its Incorporation into Lentivirus Vectors." Journal of Virology 75, no. 9 (May 1, 2001): 4129–38. http://dx.doi.org/10.1128/jvi.75.9.4129-4138.2001.

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ABSTRACT Pseudotyping retrovirus and lentivirus vectors with different viral fusion proteins is a useful strategy to alter the host range of the vectors. Although lentivirus vectors are efficiently pseudotyped by Env proteins from several different subtypes of murine leukemia virus (MuLV), the related protein from gibbon ape leukemia virus (GaLV) does not form functional pseudotypes. We have determined that this arises because of an inability of GaLV Env to be incorporated into lentivirus vector particles. By exploiting the homology between the GaLV and MuLV Env proteins, we have mapped the determinants of incompatibility in the GaLV Env. Three modifications that allowed GaLV Env to pseudotype human immunodeficiency virus type 1 particles were identified: removal of the R peptide (C-terminal half of the cytoplasmic domain), replacement of the whole cytoplasmic tail with the corresponding MuLV region, and mutation of two residues upstream of the R peptide cleavage site. In addition, we have previously proposed that removal of the R peptide from MuLV Env proteins enhances their fusogenicity by transmitting a conformational change to the ectodomain of the protein (Y. Zhao et al., J. Virol. 72:5392–5398, 1998). Our analysis of chimeric MuLV/GaLV Env proteins provides further evidence in support of this model and suggests that proper Env function involves both interactions within the cytoplasmic tail and more long-range interactions between the cytoplasmic tail, the membrane-spanning region, and the ectodomain of the protein.
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45

Goerner, Martin, Peter A. Horn, Laura Peterson, Peter Kurre, Rainer Storb, John E. J. Rasko, and Hans-Peter Kiem. "Sustained multilineage gene persistence and expression in dogs transplanted with CD34+ marrow cells transduced by RD114-pseudotype oncoretrovirus vectors." Blood 98, no. 7 (October 1, 2001): 2065–70. http://dx.doi.org/10.1182/blood.v98.7.2065.

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Анотація:
Previous studies have shown that the choice of envelope protein (pseudotype) can have a significant effect on the efficiency of retroviral gene transfer into hematopoietic stem cells. This study used a competitive repopulation assay in the dog model to evaluate oncoretroviral vectors carrying the envelope protein of the endogenous feline virus, RD114. CD34-enriched marrow cells were divided into equal aliquots and transduced with vectors produced by the RD114-pseudotype packaging cells FLYRD (LgGLSN and LNX) or by the gibbon ape leukemia virus (GALV)–pseudotype packaging cells PG13 (LNY). A total of 5 dogs were studied. One dog died because of infection before sustained engraftment could be achieved, and monitoring was discontinued after 9 months in another animal that had very low overall gene-marking levels. The 3 remaining animals are alive with follow-ups at 11, 22, and 23 months. Analyses of gene marking frequencies in peripheral blood and marrow by polymerase chain reaction revealed no significant differences between the RD114 and GALV-pseudotype vectors. The LgGLSN vector also contained the enhanced green fluorescent protein (GFP), enabling us to monitor proviral expression by flow cytometry. Up to 10% of peripheral blood cells expressed GFP shortly after transplantation and approximately 6% after the longest follow-up of 23 months. Flow cytometric analysis of hematopoietic subpopulations showed that most of the GFP-expressing cells were granulocytes, although GFP-positive lymphocytes and monocytes were also detected. In summary, these results show that RD114-pseudotype oncoretroviral vectors are able to transduce hematopoietic long-term repopulating cells and, thus, may be useful for human stem cell gene therapy.
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46

Basu, Arnab, Tatsuo Kanda, Aster Beyene, Kousuke Saito, Keith Meyer, and Ranjit Ray. "Sulfated Homologues of Heparin Inhibit Hepatitis C Virus Entry into Mammalian Cells." Journal of Virology 81, no. 8 (February 7, 2007): 3933–41. http://dx.doi.org/10.1128/jvi.02622-06.

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ABSTRACT The mechanism of entry of hepatitis C virus (HCV) through interactions between the envelope glycoproteins and specific cell surface receptors remains unclear at this time. We have previously shown with the vesicular stomatitis virus (VSV)/HCV pseudotype model that the hypervariable region 1 of the HCV E2 envelope glycoprotein helps in binding with glycosaminoglycans present on the cell surface. In this study, we have examined the binding of HCV envelope glycoproteins with chemically modified derivatives of heparin. Furthermore, we have determined the functional relevance of the interaction of heparin derivatives with HCV envelope glycoproteins for infectivity by using a human immunodeficiency virus (HIV)/HCV pseudotype, a VSV/HCV pseudotype, and cell culture-grown HCV genotype 1a. Taken together, our results suggest that the HCV envelope glycoproteins rely upon O-sulfated esters of a heparin homologue to facilitate entry into mammalian cells.
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47

Hanika, Andrea, Birthe Larisch, Eike Steinmann, Christel Schwegmann-Weßels, Georg Herrler, and Gert Zimmer. "Use of influenza C virus glycoprotein HEF for generation of vesicular stomatitis virus pseudotypes." Journal of General Virology 86, no. 5 (May 1, 2005): 1455–65. http://dx.doi.org/10.1099/vir.0.80788-0.

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Influenza C virus contains two envelope glycoproteins: CM2, a putative ion channel protein; and HEF, a unique multifunctional protein that performs receptor-binding, receptor-destroying and fusion activities. Here, it is demonstrated that expression of HEF is sufficient to pseudotype replication-incompetent vesicular stomatitis virus (VSV) that lacks the VSV glycoprotein (G) gene. The pseudotyped virus showed characteristic features of influenza C virus with respect to proteolytic activation, receptor usage and cell tropism. Chimeric glycoproteins composed of HEF ectodomain and VSV-G C-terminal domains were efficiently incorporated into VSV particles and showed receptor-binding and receptor-destroying activities but, unlike authentic HEF, did not mediate efficient infection, probably because of impaired fusion activity. HEF-pseudotyped VSV efficiently infected polarized Madin–Darby canine kidney cells via the apical plasma membrane, whereas entry of VSV-G-complemented virus was restricted to the basolateral membrane. These findings suggest that pseudotyping of viral vectors with HEF might be useful for efficient apical gene transfer into polarized epithelial cells and for targeting cells that express 9-O-acetylated sialic acids.
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48

Watanabe, Rie, Shutoku Matsuyama, Kazuya Shirato, Masami Maejima, Shuetsu Fukushi, Shigeru Morikawa, and Fumihiro Taguchi. "Entry from the Cell Surface of Severe Acute Respiratory Syndrome Coronavirus with Cleaved S Protein as Revealed by Pseudotype Virus Bearing Cleaved S Protein." Journal of Virology 82, no. 23 (September 10, 2008): 11985–91. http://dx.doi.org/10.1128/jvi.01412-08.

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ABSTRACT Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) is known to take an endosomal pathway for cell entry; however, it is thought to enter directly from the cell surface when a receptor-bound virion spike (S) protein is affected by trypsin, which induces cleavage of the S protein and activates its fusion potential. This suggests that SARS-CoV bearing a cleaved form of the S protein can enter cells directly from the cell surface without trypsin treatment. To explore this possibility, we introduced a furin-like cleavage sequence in the S protein at amino acids 798 to 801 and found that the mutated S protein was cleaved and induced cell fusion without trypsin treatment when expressed on the cell surface. Furthermore, a pseudotype virus bearing a cleaved S protein was revealed to infect cells in the presence of a lysosomotropic agent as well as a protease inhibitor, both of which are known to block SARS-CoV infection via an endosome, whereas the infection of pseudotypes with an uncleaved, wild-type S protein was blocked by these agents. A heptad repeat peptide, derived from a SARS-CoV S protein that is known to efficiently block infections from the cell surface, blocked the infection by a pseudotype with a cleaved S protein but not that with an uncleaved S protein. Those results indicate that SARS-CoV with a cleaved S protein is able to enter cells directly from the cell surface and agree with the previous observation of the protease-mediated cell surface entry of SARS-CoV.
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49

Tatsuo, Hironobu, Kazu Okuma, Kotaro Tanaka, Nobuyiki Ono, Hiroko Minagawa, Akemi Takade, Yoshiharu Matsuura, and Yusuke Yanagi. "Virus Entry Is a Major Determinant of Cell Tropism of Edmonston and Wild-Type Strains of Measles Virus as Revealed by Vesicular Stomatitis Virus Pseudotypes Bearing Their Envelope Proteins." Journal of Virology 74, no. 9 (May 1, 2000): 4139–45. http://dx.doi.org/10.1128/jvi.74.9.4139-4145.2000.

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ABSTRACT The Edmonston strain of measles virus (MV) that utilizes the human CD46 as the cellular receptor produced cytopathic effects (CPE) in all of the primate cell lines examined. In contrast, the wild-type MV strains isolated in a marmoset B-cell line B95a (the KA and Ichinose strains) replicated and produced CPE in some but not all of the primate lymphoid cell lines. To determine the mechanism underlying this difference in cell tropism, we used a recently developed recombinant vesicular stomatitis virus (VSV) containing as a reporter the green fluorescent protein gene in lieu of the VSV G protein gene (VSVΔG*). MV glycoproteins were efficiently incorporated into VSVΔG*, producing the VSV pseudotypes. VSVΔG* complemented with VSV G protein efficiently infected all of the cell lines tested. The VSV pseudotype bearing the Edmonston hemagglutinin (H) and fusion (F) protein (VSVΔG*-EdHF) infected all cell lines in which the Edmonston strain caused CPE, including the rodent cell lines to which the human CD46 gene was stably transfected. The pseudotype bearing the wild-type KA H protein and Edmonston F protein (VSVΔG*-KAHF) infected all lymphoid cell lines in which the wild-type MV strains caused CPE as efficiently as VSVΔG*-EdHF, but it did not infect any of the cell lines resistant to infection with the KA strain. The results indicate that the difference in cell tropism between these MV strains was largely determined by virus entry, in which the H proteins of respective MV strains play a decisive role.
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50

Lewis, Brian C., Nachimuthu Chinnasamy, Richard A. Morgan, and Harold E. Varmus. "Development of an Avian Leukosis-Sarcoma Virus Subgroup A Pseudotyped Lentiviral Vector." Journal of Virology 75, no. 19 (October 1, 2001): 9339–44. http://dx.doi.org/10.1128/jvi.75.19.9339-9344.2001.

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ABSTRACT We are using avian leukosis-sarcoma virus (ALSV) vectors to generate mouse tumor models in transgenic mice expressing TVA, the receptor for subgroup A ALSV. Like other classical retroviruses, ALSV requires cell division to establish a provirus after infection of host cells. In contrast, lentiviral vectors are capable of integrating their viral DNA into the genomes of nondividing cells. With the intention of initiating tumorigenesis in resting, TVA-positive cells, we have developed a system for the preparation of a human immunodeficiency virus type 1 (HIV-1)-based lentiviral vector, pseudotyped with the envelope protein of ALSV subgroup A (EnvA). The HIV(ALSV-A) vector retains the requirement for TVA on the surface of target cells and can be produced at titers of 5 × 103 infectious units (IU)/ml. By inserting the central polypurine tract (cPPT) from the HIV-1 pol gene and removing the cytoplasmic tail of EnvA, the pseudotype can be produced at titers approaching 105 IU/ml and can be concentrated by ultracentrifugation to titers of 107 IU/ml. HIV(ALSV-A) also infects embryonic fibroblasts derived from transgenic mice in which TVA expression is driven by the β-actin promoter. In addition, this lentivirus pseudotype efficiently infects these fibroblasts after cell cycle arrest, when they are resistant to infection by ALSV vectors. This system may be useful for introducing genes into somatic cells in adult TVA transgenic animals and allows evaluation of the effects of altered gene expression in differentiated cell types in vivo.
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