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Wang Y, Zhou Z, Wu X, Li T, Wu J, Cai M, Nie J, Wang W, Cui Z. Pseudotyped Viruses. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1407:1-27. [PMID: 36920689 DOI: 10.1007/978-981-99-0113-5_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Pseudotyped viruses have been constructed for many viruses. They can mimic the authentic virus and have many advantages compared to authentic viruses. Thus, they have been widely used as a surrogate of authentic virus for viral function analysis, detection of neutralizing antibodies, screening viral entry inhibitors, and others. This chapter reviewed the progress in the field of pseudotyped viruses in general, including the definition and the advantages of pseudotyped viruses, their potential usage, different strategies or vectors used for the construction of pseudotyped viruses, and factors that affect the construction of pseudotyped viruses.
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Affiliation(s)
- Youchun Wang
- Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
- Institute of Medical Biology, Chinese Academy of Medicine Sciences & Peking Union Medical College, Kunming, China.
| | - Zehua Zhou
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Xi Wu
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Tao Li
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Jiajing Wu
- Beijing Yunling Biotechnology Co., Ltd., Beijing, China
| | - Meina Cai
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Jianhui Nie
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Wenbo Wang
- Division of Monoclonal Antibody Products, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
| | - Zhimin Cui
- Division of HIV/AIDS and Sex-transmitted Virus Vaccines, National Institutes for Food and Drug Control (NIFDC) and WHO Collaborating Center for Standardization and Evaluation of Biologicals, Beijing, China
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2
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Marchand C, Lemay G, Archambault D. Identification of the nuclear and nucleolar localization signals of the Feline immunodeficiency virus Rev protein. Virus Res 2020; 290:198153. [PMID: 33010374 DOI: 10.1016/j.virusres.2020.198153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 08/30/2020] [Accepted: 08/31/2020] [Indexed: 10/23/2022]
Abstract
Lentivirus genomes code for a regulatory protein essential for virus replication termed Rev. The Rev protein binds to partially spliced and unspliced viral RNAs and mediates their nuclear export. Therefore, Rev possesses functional domains that enable its shuttling between the cytoplasm and the nucleus. The Feline immunodeficiency virus (FIV), a lentivirus, can lead to an immunodeficiency syndrome after a long incubation period, similar to that associated with the human immunodeficiency virus type 1 (HIV-1). The FIV Rev functional domains have been predicted only by homology with those of HIV-1 Rev. In the present study, the nuclear and nucleolar localization signals (NLS and NoLS, respectively) of the FIV Rev were examined. A series of FIV Rev deletion mutants fused to the enhanced green fluorescent protein (EGFP) were used to localize the NLS in a region spanning amino acids (aa) 81-100. By using alanine substitution mutants, basic residues present between the amino acids (aa) 84-99 of the FIV Rev protein sequence were identified to form the NLS, whereas those between aa 82-95 were associated with the NoLS function. These results further enhance our understanding of how Rev exerts its role in the replication cycle of lentiviruses.
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Affiliation(s)
- Claude Marchand
- Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Québec, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, Québec, Canada
| | - Guy Lemay
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, Québec, Canada
| | - Denis Archambault
- Département des Sciences Biologiques, Université du Québec à Montréal, Montréal, Québec, Canada.
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3
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Cano-Ortiz L, Maletich Junqueira D, Comerlato J, Zani A, Santos Costa C, Michel Roehe P, Franco AC. Absence of A3Z3-Related Hypermutations in the env and vif Proviral Genes in FIV Naturally Infected Cats. Viruses 2018; 10:v10060296. [PMID: 29857485 PMCID: PMC6024795 DOI: 10.3390/v10060296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 05/24/2018] [Accepted: 05/27/2018] [Indexed: 11/16/2022] Open
Abstract
Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3; A3) proteins comprise an important family of restriction factors that produce hypermutations on proviral DNA and are able to limit virus replication. Vif, an accessory protein present in almost all lentiviruses, counteracts the antiviral A3 activity. Seven haplotypes of APOBEC3Z3 (A3Z3) were described in domestic cats (hap I–VII), and in-vitro studies have demonstrated that these proteins reduce infectivity of vif-defective feline immunodeficiency virus (FIV). Moreover, hap V is resistant to vif-mediated degradation. However, studies on the effect of A3Z3 in FIV-infected cats have not been developed. Here, the correlation between APOBEC A3Z3 haplotypes in domestic cats and the frequency of hypermutations in the FIV vif and env genes were assessed in a retrospective cohort study with 30 blood samples collected between 2012 and 2016 from naturally FIV-infected cats in Brazil. The vif and env sequences were analyzed and displayed low or undetectable levels of hypermutations, and could not be associated with any specific A3Z3 haplotype.
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Affiliation(s)
- Lucía Cano-Ortiz
- Virology Laboratory, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite 500, Porto Alegre, RS CEP 90150-070, Brazil.
| | - Dennis Maletich Junqueira
- Health Science Department, UniRitter Laureate International Universities, Rua Orfanotrófio, 555, Alto Teresópolis, Porto Alegre, RS CEP 90840-440C, Brazil.
| | - Juliana Comerlato
- Virology Laboratory, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite 500, Porto Alegre, RS CEP 90150-070, Brazil.
| | - André Zani
- Virology Laboratory, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite 500, Porto Alegre, RS CEP 90150-070, Brazil.
| | - Cristina Santos Costa
- Virology Laboratory, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite 500, Porto Alegre, RS CEP 90150-070, Brazil.
| | - Paulo Michel Roehe
- Virology Laboratory, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite 500, Porto Alegre, RS CEP 90150-070, Brazil.
| | - Ana Cláudia Franco
- Virology Laboratory, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Rua Sarmento Leite 500, Porto Alegre, RS CEP 90150-070, Brazil.
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4
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Applications of the FIV Model to Study HIV Pathogenesis. Viruses 2018; 10:v10040206. [PMID: 29677122 PMCID: PMC5923500 DOI: 10.3390/v10040206] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 04/17/2018] [Accepted: 04/17/2018] [Indexed: 12/15/2022] Open
Abstract
Feline immunodeficiency virus (FIV) is a naturally-occurring retrovirus that infects domestic and non-domestic feline species, producing progressive immune depletion that results in an acquired immunodeficiency syndrome (AIDS). Much has been learned about FIV since it was first described in 1987, particularly in regard to its application as a model to study the closely related lentivirus, human immunodeficiency virus (HIV). In particular, FIV and HIV share remarkable structure and sequence organization, utilize parallel modes of receptor-mediated entry, and result in a similar spectrum of immunodeficiency-related diseases due to analogous modes of immune dysfunction. This review summarizes current knowledge of FIV infection kinetics and the mechanisms of immune dysfunction in relation to opportunistic disease, specifically in regard to studying HIV pathogenesis. Furthermore, we present data that highlight changes in the oral microbiota and oral immune system during FIV infection, and outline the potential for the feline model of oral AIDS manifestations to elucidate pathogenic mechanisms of HIV-induced oral disease. Finally, we discuss advances in molecular biology, vaccine development, neurologic dysfunction, and the ability to apply pharmacologic interventions and sophisticated imaging technologies to study experimental and naturally occurring FIV, which provide an excellent, but often overlooked, resource for advancing therapies and the management of HIV/AIDS.
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5
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Kenyon JC, Lever AML. The molecular biology of feline immunodeficiency virus (FIV). Viruses 2011; 3:2192-213. [PMID: 22163340 PMCID: PMC3230847 DOI: 10.3390/v3112192] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Revised: 10/31/2011] [Accepted: 10/31/2011] [Indexed: 11/29/2022] Open
Abstract
Feline immunodeficiency virus (FIV) is widespread in feline populations and causes an AIDS-like illness in domestic cats. It is highly prevalent in several endangered feline species. In domestic cats FIV infection is a valuable small animal model for HIV infection. In recent years there has been sa significant increase in interest in FIV, in part to exploit this, but also because of the potential it has as a human gene therapy vector. Though much less studied than HIV there are many parallels in the replication of the two viruses, but also important differences and, despite their likely common origin, the viruses have in some cases used alternative strategies to overcome similar problems. Recent advances in understanding the structure and function of FIV RNA and proteins and their interactions has enhanced our knowledge of FIV replication significantly, however, there are still many gaps. This review summarizes our current knowledge of FIV molecular biology and its similarities with, and differences from, other lentiviruses.
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Affiliation(s)
- Julia C Kenyon
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK.
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6
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Pathogenicity and rapid growth kinetics of feline immunodeficiency virus are linked to 3' elements. PLoS One 2011; 6:e24020. [PMID: 21887365 PMCID: PMC3162592 DOI: 10.1371/journal.pone.0024020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Accepted: 07/28/2011] [Indexed: 11/19/2022] Open
Abstract
Chimeric viruses constructed between a highly pathogenic Feline Immunodeficiency Virus isolate (FIV-C36) and a less pathogenic but neurotropic strain (FIV-PPR) have been used to map viral genetic determinants of in vivo pathogenicity. Chimeric virus FIV-PCenv, which contains FIV-C36 genome from the 3′ region of pol to upstream of the 3′LTR on an FIV-PPR backbone, was previously shown to be replication-competent in vivo, inducing altered CD4+ T-cell and neutrophil profiles intermediate between parental strains following a delay in viral replication during initial infection. Examination of FIV-PCenv proviral sequences recovered at week 11 post-infection revealed two changes compared to initial viral inoculum; the most significant being arginine to histidine in the integrase region of Pol at residue 813 (R813H). Pooled plasma from the initial in vivo study was used to inoculate a second cohort of cats to determine whether similar virulence and kinetics could be established following primary infection. Viral replication kinetics and immunocyte profiles were monitored in blood, bone marrow, and saliva over a one-year period. Passaged FIV-PCenv again displayed intermediate phenotype between parental strains, but unlike primary experiments, the onset of acute viremia was not delayed. CD4/8 alterations were noted in all groups of animals, though significant changes from controls were delayed in FIV-PPR infected animals compared to FIV-C36 and FIV-PCenv. In vivo passage of FIV-PCenv increased replication-competence relative to the initial molecularly-cloned chimera in association with one adaptive nucleotide change in the 5′ end of the genome relative to primary tissue culture inoculum, while mutations in the 3′ end of the genome were not detected. The results are consistent with the interpretation that 3′ elements contribute to heightened virulence of FIV-C36, and that integrase residue 813 plays an important role in facilitating successful in vivo replication.
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7
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Abstract
Animal models for human immunodeficiency virus (HIV) infection play a key role in understanding the pathogenesis of AIDS and the development of therapeutic agents and vaccines. As the only lentivirus that causes an immunodeficiency resembling that of HIV infection, in its natural host, feline immunodeficiency virus (FIV) has been a unique and powerful model for AIDS research. FIV was first described in 1987 by Niels Pedersen and co-workers as the causative agent for a fatal immunodeficiency syndrome observed in cats housed in a cattery in Petaluma, California. Since this landmark observation, multiple studies have shown that natural and experimental infection of cats with biological isolates of FIV produces an AIDS syndrome very similar in pathogenesis to that observed for human AIDS. FIV infection induces an acute viremia associated with Tcell alterations including depressed CD4 :CD8 T-cell ratios and CD4 T-cell depletion, peripheral lymphadenopathy, and neutropenia. In later stages of FIV infection, the host suffers from chronic persistent infections that are typically self-limiting in an immunocompetent host, as well as opportunistic infections, chronic diarrhea and wasting, blood dyscracias, significant CD4 T-cell depletion, neurologic disorders, and B-cell lymphomas. Importantly, chronic FIV infection induces a progressive lymphoid and CD4 T-cell depletion in the infected cat. The primary mode of natural FIV transmission appears to be blood-borne facilitated by fighting and biting. However, experimental infection through transmucosal routes (rectal and vaginal mucosa and perinatal) have been well documented for specific FIV isolates. Accordingly, FIV disease pathogenesis exhibits striking similarities to that described for HIV-1 infection.
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8
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Matsuda M, Matsuda N, Watanabe A, Fujisawa R, Yamamoto K, Masuda M. Cell cycle arrest induction by an adenoviral vector expressing HIV-1 Vpr in bovine and feline cells. Biochem Biophys Res Commun 2004; 311:748-53. [PMID: 14623336 DOI: 10.1016/j.bbrc.2003.10.064] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An accessory protein, Vpr, of human immunodeficiency virus type 1 (HIV-1) induces the cell cycle G(2)/M arrest in primate cells, but not in rodent cells, suggesting that a species-specific factor might be involved in the phenomenon. To study whether Vpr can cause G(2)/M arrest in non-primate cells, a novel adenoviral vector, Ad-VIG, co-expressing HIV-1 Vpr and green fluorescent protein (GFP) was constructed and infected on cell lines derived from various mammalian species. With its ability to express GFP, Ad-VIG enabled flow cytometric evaluation of transduction efficiency in the infected cells, and Western blot analysis showed successful expression of Vpr in the vector-transduced cells. Upon Ad-VIG infection, human HeLa, African green monkey Vero, feline CRFK, and bovine MDBK cells manifested cell cycle G(2)/M arrest. This is the first study showing that non-primate feline and bovine cells are susceptible to Vpr-induced cell cycle arrest.
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Affiliation(s)
- Mari Matsuda
- Department of Microbiology, Dokkyo University School of Medicine, Mibu, Tochigi 321-0293, Japan
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9
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Gemeniano MC, Sawai ET, Leutenegger CM, Sparger EE. Feline immunodeficiency virus ORF-Ais required for virus particle formation and virus infectivity. J Virol 2003; 77:8819-30. [PMID: 12885901 PMCID: PMC167212 DOI: 10.1128/jvi.77.16.8819-8830.2003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The orf-A (orf-2) gene of feline immunodeficiency virus (FIV) is a small open reading frame predicted to encode a 77-amino-acid protein that contains putative domains similar to those of the ungulate lentiviral Tat protein. Orf-A is reported to be critical for efficient viral replication in vitro and in vivo. A series of FIV-pPPR-derived proviruses with in-frame deletions and point mutations within orf-A were constructed and tested for replication in feline lymphoid cells. Orf-A mutant proviruses were also tested for viral gene and protein expression, viral particle formation, and virion infectivity. Deletions within orf-A severely restricted FIV replication in feline peripheral blood mononuclear cells (PBMC) and interleukin-2-dependent T-cell lines. In addition, substitutions of alanines for leucines in the putative leucine-rich domain, for cysteines in the putative cysteine-rich domain, and for a tryptophan at position 43 in Orf-A restricted the replication of FIV mutants. Deletions and point mutations in orf-A imposed a small effect or no effect on FIV long-terminal-repeat-driven viral gene expression and had no effect on viral protein expression. However, release of cell-free, virion-associated viral RNA in supernatants from cells transfected with orf-A mutant proviruses was severely restricted but was rescued by cotransfection with a wild-type Orf-A expression vector. In addition, virions derived from orf-A mutant proviruses expressed reduced infectivity for feline PBMC. Our findings suggest that Orf-A functions involve multiple steps of the FIV life cycle including both virion formation and infectivity. Furthermore, these observations suggest that Orf-A represents an FIV-encoded analog more similar to the accessory gene vpr, vpu, or nef than to the regulatory gene tat encoded by the primate lentiviruses.
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Affiliation(s)
- Malou C Gemeniano
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California 95616, USA
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10
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Song JJ, Lee B, Chang JW, Kim JH, Kwon YK, Lee H. Optimization of vesicular stomatitis virus-G pseudotyped feline immunodeficiency virus vector for minimized cytotoxicity with efficient gene transfer. Virus Res 2003; 93:25-30. [PMID: 12727339 DOI: 10.1016/s0168-1702(03)00047-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
FIV-based lentiviral vector has shown a unique opportunity as an efficient gene delivery vehicle, especially to nondividing human cells. Here, we genetically reconstructed the FIV-based vector by serially deleting residual virus genes of gag and vif, leading to minimized cytotoxicity together with efficient virus production and gene transfer. The modified FIV- based vector was generated by transiently transfecting 293T cells with three plasmids of the gene transfer vector with minimal gag region, the packaging plasmid without vif and the VSV-G-expressing plasmid. The vector was routinely generated as many as 1 x 10(7) transducing particles per ml and easily concentrated by simple centrifugation. The cytotoxic effect significantly decreased in sensitive cells to FIV infection even at high multiplicity of infection (MOI), such as 500. Moreover, the transduction efficiency was consistently retained after cell cycle was arrested in a variety of human cells. Taken together, our results suggest that the modified VSV-G pseudotyped FIV-based vector efficiently transduce dividing and nondividing human cells with minimal cytotoxicity.
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Affiliation(s)
- Jae Jin Song
- Institute for Cancer Research, Yonsei University College of Medicine, Seoul, South Korea
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11
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Pistello M, Moscardini M, Mazzetti P, Bonci F, Zaccaro L, Isola P, Freer G, Specter S, Matteucci D, Bendinelli M. Development of feline immunodeficiency virus ORF-A (tat) mutants: in vitro and in vivo characterization. Virology 2002; 298:84-95. [PMID: 12093176 DOI: 10.1006/viro.2002.1442] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A functional ORF-A is essential for efficient feline immunodeficiency virus replication in lymphocytes. We have characterized a series of mutants of the Petaluma strain, derived from p34TF10 and having different combinations of stop codons and increasingly long deletions in ORF-A. Six clones proved fully replicative in fibroblastoid Crandell feline kidney cells and monocyte-derived macrophage cultures but failed to replicate in T cell lines and primary lymphoblasts. Cats inoculated with three selected mutants had considerably milder infections than controls given intact ORF-A virus. In vivo, the mutants maintained growth properties similar to those in vitro for at least 7 months, except that replication in lymphoid cells was strongly reduced but not ablated. One mutant underwent extensive ORF-A changes without, however, reverting to wild-type. Antiviral immune responses were feeble in all cats, suggesting that viral loads were too low to represent a sufficiently powerful antigenic stimulus.
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Affiliation(s)
- M Pistello
- Retrovirus Center and Virology Section, University of Pisa, Italy.
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12
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Stein CS, Davidson BL. Gene transfer to the brain using feline immunodeficiency virus-based lentivirus vectors. Methods Enzymol 2002; 346:433-54. [PMID: 11883084 DOI: 10.1016/s0076-6879(02)46070-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Colleen S Stein
- College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA
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13
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Briquet S, Richardson J, Vanhée-Brossollet C, Vaquero C. Natural antisense transcripts are detected in different cell lines and tissues of cats infected with feline immunodeficiency virus. Gene 2001; 267:157-64. [PMID: 11313142 DOI: 10.1016/s0378-1119(01)00404-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Feline immunodeficiency virus (FIV) is a lentivirus inducing an AIDS-like disease in cats, thus providing an interesting model for AIDS study. FIV and HIV-1 possess a similar genomic arrangement of structural and non-structural genes, whose expression is regulated by related genetic mechanisms. On the DNA strand complementary to the HIV-1 envelope messenger, an open reading frame (ORF) has been identified which encompasses the Rev Responsive Element (RRE), a cis-acting element critical to HIV gene expression. This ORF was highly conserved among HIV-1 isolates and had the potential to encode a hydrophobic protein. A corresponding antisense transcript was detected in cells infected with HIV-1, and appeared to encode an antisense protein. In the present study, we have identified a well-conserved antisense ORF, also coincident with the RRE region, in the genome of 21 FIV isolates. The predicted protein, 103 amino acids in length, is highly hydrophobic, as is the case for that of HIV-1. In addition, we have shown that a corresponding transcript, complementary to the transmembrane sequence of the FIV envelope gene, was produced in different cellular and viral contexts, that is, ex vivo and in vivo in FIV infected cell lines and tissues of infected cats, respectively. Expression of antisense transcripts might therefore be of general importance in the natural history of retroviruses.
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Affiliation(s)
- S Briquet
- INSERM U511, CHU Pitié-Salpêtrière, 91 boulevard de l'Hôpital, 75013 Paris, France
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14
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Curran MA, Kaiser SM, Achacoso PL, Nolan GP. Efficient transduction of nondividing cells by optimized feline immunodeficiency virus vectors. Mol Ther 2000; 1:31-8. [PMID: 10933909 DOI: 10.1006/mthe.1999.0007] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Second- and third-generation three-plasmid vector systems, termed FELIX, were constructed from feline immunodeficiency virus (FIV). To enhance vector production, the weak FIV long terminal repeat promoter was replaced with the human cytomegalovirus enhancer/promoter. To construct a minimal system in which Gag-Pol was the only viral protein present, the cytoplasmic transport element was used in place of the FIV Rev-RRE system to facilitate nuclear export of Gag-Pol and the transfer vector. Unconcentrated vector titers routinely exceeded 1 x 10(6) IU/mL for most constructs tested. Second- and optimized third-generation vectors were capable of efficiently infecting G1/S- and G2/M-arrested cells. FIV-based FELIX vectors transduced human dendritic cells, hepatocytes, and aortic smooth muscle with efficiencies similar to that of a control 3T3 cell line. All three of these primary cell types were transducible by both the second- and third-generation FELIX vectors, demonstrating that FIV Gag-Pol alone contains the determinants necessary for transduction of primary cells. In cross-packaging tests, we observed that HIV Gag-Pol does not substantially package FIV vectors; consequently, use of such vectors in human immunodeficiency virus-infected cells should not lead to efficient mobilization of the inserted gene. Thus, this FIV-based vector system offers high efficiency and stable delivery of genes to numerous nondividing and primary cell types, opening new avenues for biological inquiry into normal human cells.
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Affiliation(s)
- M A Curran
- Program in Immunology, Stanford University Medical Center, California 94305-5332, USA.
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15
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Johnston JC, Gasmi M, Lim LE, Elder JH, Yee JK, Jolly DJ, Campbell KP, Davidson BL, Sauter SL. Minimum requirements for efficient transduction of dividing and nondividing cells by feline immunodeficiency virus vectors. J Virol 1999; 73:4991-5000. [PMID: 10233961 PMCID: PMC112543 DOI: 10.1128/jvi.73.6.4991-5000.1999] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The development of gene delivery vectors based on feline immunodeficiency virus (FIV) is an attractive alternative to vectors based on primate sources for the delivery of genes into humans. To investigate the requirements for efficient transduction of dividing and nondividing cells by vector particles based on FIV, a series of packaging and vector constructs was generated for which viral gene expression was minimized and from which unnecessary cis-acting sequences were deleted. Pseudotyped vector particles produced in 293T cells were used to transduce various target cells, including contact-inhibited human skin fibroblasts and growth-arrested HT1080 cells. FIV vectors in which the U3 promoter was replaced with the cytomegalovirus promoter gave rise to over 50-fold-higher titers than FIV vectors containing the complete FIV 5' long terminal repeat (LTR). Comparison of the transduction efficiencies of vectors containing different portions of the FIV Gag coding region indicates that at least a functional part of the FIV packaging signal (Psi) is located within an area which includes the 5' LTR and the first 350 bp of gag. Transduction efficiencies of vectors prepared without FIV vif and orf2 accessory gene expression did not differ substantially from those of vectors prepared with accessory gene expression in either dividing or nondividing cells. The requirement for FIV rev-RRE was, however, demonstrated by the inefficient production of vector particles in the absence of rev expression. Together, these results demonstrate the efficient transduction of nondividing cells in vitro by a multiply attenuated FIV vector and contribute to an understanding of the minimum requirements for efficient vector production and infectivity. In addition, we describe the ability of an FIV vector to deliver genes in vivo into hamster muscle tissue.
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Affiliation(s)
- J C Johnston
- Center for Gene Therapy, Chiron Technologies, San Diego, California 92121, USA
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16
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Inoshima Y, Miyazawa T, Mikami T. In vivo functions of the auxiliary genes and regulatory elements of feline immunodeficiency virus. Vet Microbiol 1998; 60:141-53. [PMID: 9646446 DOI: 10.1016/s0378-1135(98)00157-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Feline immunodeficiency virus (FIV) is a widespread lentivirus of domestic cats that causes an acquired immunodeficiency syndrome (AIDS)-like disease similar to human AIDS caused by human immunodeficiency virus. FIV has a complex genome structure including structural, enzymatic and auxiliary genes and regulatory elements. In this article, we review the in vivo roles of some of these FIV auxiliary genes and regulatory elements, especially focusing on the dUTPase, vif, and ORF-A genes and AP-1 binding site in the enhancer region of the long terminal repeat, by comparison with those of other non-primate lentiviruses. These genes and elements are considered to be important for viral replication, immunological response and pathogenesis in cats.
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Affiliation(s)
- Y Inoshima
- Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Japan
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Ikeda Y, Kawaguchi Y, Inoshima Y, Kohmoto M, Shimojima M, Inada G, Sato E, Kai C, Miyazawa T, Mikami T. The effects of treatment with chemical agents or infection with feline viruses on protein-binding properties of the feline immunodeficiency virus long terminal repeat. Virus Res 1997; 51:203-12. [PMID: 9498618 DOI: 10.1016/s0168-1702(97)00094-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The effects of treatment with chemical agents or infection with feline viruses on protein-binding properties of the feline immunodeficiency virus (FIV) long terminal repeat (LTR) were examined by gel-mobility-shift assays using oligonucleotides designed to represent putative AP-1 or ATF motif from the FIV LTR. Infection with FIV led to less nuclear proteins binding to the AP-1 and ATF sites, suggesting that proteins binding to the sites were consumed or suppressed by FIV-replication in FIV-infected cells. Nuclear proteins that bind to the AP-1 or ATF site were examined by using extracts from Crandell feline kidney (CRFK) cells treated with TPA (a phorbol ester; a strong activator of protein kinase C) or forskolin (an inducer of cyclic-AMP), or infection with feline herpesvirus type 1 (FHV-1). Although TPA or forskolin treatment moderately increased the level of both proteins that bound to AP-1 and ATF sites, FHV-1 infection markedly changed the protein-binding patterns of the sites. Furthermore, FHV-1-induced proteins that bind adjacent to the transcriptional initiation site of FIV promoter were also observed in FHV-1-infected CRFK cells, suggesting that the FHV-1-induced-proteins affects the transcription of FIV through the AP-1, ATF and leader sequences.
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Affiliation(s)
- Y Ikeda
- Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan
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18
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Winkler I, Bodem J, Haas L, Zemba M, Delius H, Flower R, Flügel RM, Löchelt M. Characterization of the genome of feline foamy virus and its proteins shows distinct features different from those of primate spumaviruses. J Virol 1997; 71:6727-41. [PMID: 9261397 PMCID: PMC191953 DOI: 10.1128/jvi.71.9.6727-6741.1997] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The genome of the feline foamy virus (FeFV) isolate FUV was characterized by molecular cloning and nucleotide sequence analysis of subgenomic proviral DNA. The overall genetic organization of FeFV and protein sequence comparisons of different FeFV genes with their counterparts from other known foamy viruses confirm that FeFV is a complex foamy virus. However, significant differences exist when FeFV is compared with primate foamy viruses. The FeFV Gag protein is smaller than that of the primate spumaviruses, mainly due to additional MA/CA sequences characteristic of the primate viruses only. Gag protein sequence motifs of the NC domain of primate foamy viruses assumed to be involved in genome encapsidation are not conserved in FeFV. FeFV Gag and Pol proteins were detected with monospecific antisera directed against Gag and Pol domains of the human foamy virus and with antisera from naturally infected cats. Proteolytic processing of the FeFV Gag precursor was incomplete, whereas more efficient proteolytic cleavage of the pre125Pro-Pol protein was observed. The active center of the FeFV protease contains a Gln that replaces an invariant Gly residue at this position in other retroviral proteases. Functional studies on FeFV gene expression directed by the promoter of the long terminal repeat showed that FeFV gene expression was strongly activated by the Bell/Tas transactivator protein. The FeFV Bell/Tas transactivator is about one-third smaller than its counterpart of primate spumaviruses. This difference is also reflected by a limited sequence similarity and only a moderate conservation of structural motifs of the different foamy virus transactivators analyzed.
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Affiliation(s)
- I Winkler
- Abteilung Retrovirale Genexpression, Forschungsschwerpunkt Angewandte Tumorvirologie, Deutsches Krebsforschungszentrum, Heidelberg, Germany
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19
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Inoshima Y, Kohmoto M, Ikeda Y, Yamada H, Kawaguchi Y, Tomonaga K, Miyazawa T, Kai C, Umemura T, Mikami T. Roles of the auxiliary genes and AP-1 binding site in the long terminal repeat of feline immunodeficiency virus in the early stage of infection in cats. J Virol 1996; 70:8518-26. [PMID: 8970975 PMCID: PMC190943 DOI: 10.1128/jvi.70.12.8518-8526.1996] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
To examine the roles of auxiliary genes and the AP-1 binding site in the long terminal repeat of feline immunodeficiency virus (FIV) in vivo, three mutant viruses, which are defective in the vif gene ([delta]vif), ORF-A gene (deltaORF-A), and AP-1 binding site (deltaAP-1), and wild-type virus as a positive control were separately inoculated into three specific-pathogen-free cats. These cats were assessed by measuring the number of proviral DNA copies in peripheral blood mononuclear cells (PBMCs), the CD4/CD8 ratio and antibody responses to FIV for 16 weeks and then examining histological changes at necropsy. Although viral DNAs were detected in PBMCs from all 12 cats to various degrees until 16 weeks postinoculation, no virus was recovered from PBMCs of cats infected with (delta)vif virus during the observation period. However, a very weak antibody response was induced in one cat infected with the (delta)vif virus. In contrast, despite the successful recovery of virus from both groups of cats infected with deltaORF-A and deltaAP-1 virus, antibody responses and decrease in the CD4/CD8 ratio in the groups were milder than those in cats infected with wild-type virus. Furthermore, the numbers of proviral DNA copies in PBMCs from the two groups were not able to reach the level in cats infected with wild-type virus during the observation period. From these results, we conclude that these mutant viruses are still infectious for cats but failed in efficient viral replication and suggest that these auxiliary genes and enhancer element are important or essential to full viral replication kinetics and presumably to full pathogenicity during the early stage of infection in vivo.
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Affiliation(s)
- Y Inoshima
- Department of Veterinary Microbiology, Faculty of Agriculture, The University of Tokyo, Bunkyo-ku, Japan
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