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Cavalieri V, Baiamonte E, Lo Iacono M. Non-Primate Lentiviral Vectors and Their Applications in Gene Therapy for Ocular Disorders. Viruses 2018; 10:E316. [PMID: 29890733 PMCID: PMC6024700 DOI: 10.3390/v10060316] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 12/18/2022] Open
Abstract
Lentiviruses have a number of molecular features in common, starting with the ability to integrate their genetic material into the genome of non-dividing infected cells. A peculiar property of non-primate lentiviruses consists in their incapability to infect and induce diseases in humans, thus providing the main rationale for deriving biologically safe lentiviral vectors for gene therapy applications. In this review, we first give an overview of non-primate lentiviruses, highlighting their common and distinctive molecular characteristics together with key concepts in the molecular biology of lentiviruses. We next examine the bioengineering strategies leading to the conversion of lentiviruses into recombinant lentiviral vectors, discussing their potential clinical applications in ophthalmological research. Finally, we highlight the invaluable role of animal organisms, including the emerging zebrafish model, in ocular gene therapy based on non-primate lentiviral vectors and in ophthalmology research and vision science in general.
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Affiliation(s)
- Vincenzo Cavalieri
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze Edificio 16, 90128 Palermo, Italy.
- Advanced Technologies Network (ATeN) Center, University of Palermo, Viale delle Scienze Edificio 18, 90128 Palermo, Italy.
| | - Elena Baiamonte
- Campus of Haematology Franco e Piera Cutino, Villa Sofia-Cervello Hospital, 90146 Palermo, Italy.
| | - Melania Lo Iacono
- Campus of Haematology Franco e Piera Cutino, Villa Sofia-Cervello Hospital, 90146 Palermo, Italy.
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2
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de Castro FL, Junqueira DM, de Medeiros RM, da Silva TR, Costenaro JG, Knak MB, de Matos Almeida SE, Campos FS, Roehe PM, Franco AC. Analysis of single-nucleotide polymorphisms in the APOBEC3H gene of domestic cats (Felis catus) and their association with the susceptibility to feline immunodeficiency virus and feline leukemia virus infections. INFECTION GENETICS AND EVOLUTION 2014; 27:389-94. [DOI: 10.1016/j.meegid.2014.08.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/20/2014] [Accepted: 08/21/2014] [Indexed: 10/24/2022]
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3
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Wu Y, Tan J, Su Y, Qiao W, Geng Y, Chen Q. Transcription factor AP1 modulates the internal promoter activity of bovine foamy virus. Virus Res 2009; 147:139-44. [PMID: 19853631 DOI: 10.1016/j.virusres.2009.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 10/06/2009] [Accepted: 10/09/2009] [Indexed: 11/28/2022]
Abstract
Foamy virus contains two promoters, which are the canonical long terminal repeat (LTR) promoter and the internal promoter (IP). FV gene expression was considered to initiate at the internal promoter. However, little was known about how basal transcription of IP was triggered by the host cellular factors. Previous studies found some cellular proteins could affect HFV viral replication, but it was no known whether the AP1 signal pathway was involved in the activation of viral replication or not. In this study, we reported that treatment with TPA or AP1 increased basal transcription of IP and did not affect basal transcription of the promoter in the LTR. In addition, the c-Jun mutant blocked the IP activity stimulated by TPA. Two AP1 binding sites located in BFV-IP promoter were found by bioinformatics and mutants of two AP1 binding sites decreased luciferase reporter activity of IP activated by AP1. EMSA assay showed that two AP1 binding sites could bind to c-Jun/c-Fos heterodimeric. We also found TPA and AP1 enhanced BFV3026 replication. Taken together, these data suggested that AP1 was a positive regulator of BFV internal promoter.
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Affiliation(s)
- YaFeng Wu
- College of Lifesciences, Nankai University, Tianjin 300071, PR China
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4
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Münk C, Hechler T, Chareza S, Löchelt M. Restriction of feline retroviruses: lessons from cat APOBEC3 cytidine deaminases and TRIM5alpha proteins. Vet Immunol Immunopathol 2009; 134:14-24. [PMID: 19896724 DOI: 10.1016/j.vetimm.2009.10.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The interplay between viral and cellular factors determines the outcome of an initial contact between a given virus and its natural host or upon encounter of a novel host. Thus, the potential of inducing disease as well as crossing host species barriers are the consequences of the molecular interactions between the parasite and its susceptible, tolerant or resistant host. Cellular restriction factors, for instance APOBEC3 and TRIM5 proteins, targeting defined pathogens or groups of pathogens as well as viral genes counter-acting these cellular defense systems are of prime importance in this respect and may even represent novel targets for prevention and therapy of virus infections. Due to the importance of host-encoded antiviral restriction and viral counter-defense for pathogenicity and host tropism, the responsible molecular factors and mechanisms are currently under intense investigation. In this review we will introduce host restriction and retroviral counter-defense systems with a special emphasis on the cat and its naturally occurring exogenous retroviruses which is a valid model for human disease, a model that will contribute to increase our basic understanding and potential applications of these important aspects of host-virus interaction.
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Affiliation(s)
- Carsten Münk
- Clinic for Gasteroenterology, Hepatology and Infectiology, Heinrich-Heine-University, Düsseldorf, Germany
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5
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Teixeira B, Rajão D, Haddad J, Leite R, Reis J. Ocorrência do vírus da imunodeficiência felina e do vírus da leucemia felina em gatos domésticos mantidos em abrigos no município de Belo Horizonte. ARQ BRAS MED VET ZOO 2007. [DOI: 10.1590/s0102-09352007000400019] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Investigou-se a ocorrência da infecção pelo vírus da imunodeficiência felina (FIV) e pelo vírus da leucemia felina (FeLV) em gatos domésticos, provenientes de dois abrigos, no município de Belo Horizonte. Amostras de sangue de 145 animais foram coletadas e testadas para detecção do FIV pela reação em cadeia da polimerase (PCR). Destas amostras, 40 foram testadas para o antígeno p26 de FeLV por meio de ELISA. Observaram-se duas fêmeas (1,4%) e quatro machos (2,8%) positivos para FIV e nove fêmeas (22,5%) e quatro machos (10,0%) positivos para FeLV.
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6
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Vobis M, D'Haese J, Mehlhorn H, Mencke N. Evidence of horizontal transmission of feline leukemia virus by the cat flea ( Ctenocephalides felis). Parasitol Res 2003; 91:467-70. [PMID: 14557874 DOI: 10.1007/s00436-003-0949-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2003] [Accepted: 06/24/2003] [Indexed: 10/26/2022]
Abstract
The feline leukemia virus (FeLV) is a naturally occurring and widespread retrovirus among domestic cats. The virus is mainly transmitted horizontally through saliva, blood and other body fluids by close contact between cats. Vectors other than cats, e.g. blood-sucking parasites, have not been reported. This study tested the vector potential of the cat flea ( Ctenocephalides felis) for FeLV. In a first feeding, fleas were fed for 24 h with blood from a FeLV-infected cat with persistent viremia. FeLV could be detected in the fleas, as well as in their feces. Fleas were then divided in two populations and fed in a second feeding for 5 h or 24 h with non-infected non-viremic blood. FeLV was again detected in the fleas and their feces. In addition, the two resulting blood samples of the second feeding were subsequently tested for FeLV and both samples were positive for FeLV RNA. The cat flea transmitted the FeLV from one blood sample to another. In a third feeding, the same populations of fleas were fed again with non-infected blood for 5 h or 24 h. This time FeLV was not detected in the fleas, or in the feces or blood samples. Results show that cat fleas are potential vectors for FeLV RNA in vitro and probably also in vivo.
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Affiliation(s)
- M Vobis
- Institute for Zoomorphology, Cell Biology and Parasitology, Heinrich-Heine University, 40225, Düsseldorf, Germany
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7
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Browning MT, Schmidt RD, Lew KA, Rizvi TA. Primate and feline lentivirus vector RNA packaging and propagation by heterologous lentivirus virions. J Virol 2001; 75:5129-40. [PMID: 11333894 PMCID: PMC114918 DOI: 10.1128/jvi.75.11.5129-5140.2001] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Development of safe and effective gene transfer systems is critical to the success of gene therapy protocols for human diseases. Currently, several primate lentivirus-based gene transfer systems, such as those based on human and simian immunodeficiency viruses (HIV/SIV), are being tested; however, their use in humans raises safety concerns, such as the generation of replication-competent viruses through recombination with related endogenous retroviruses or retrovirus-like elements. Due to the greater phylogenetic distance from primate lentiviruses, feline immunodeficiency virus (FIV) is becoming the lentivirus of choice for human gene transfer systems. However, the safety of FIV-based vector systems has not been tested experimentally. Since lentiviruses such as HIV-1 and SIV have been shown to cross-package their RNA genomes, we tested the ability of FIV RNA to get cross-packaged into primate lentivirus particles such as HIV-1 and SIV, as well as a nonlentiviral retrovirus such as Mason-Pfizer monkey virus (MPMV), and vice versa. Our results reveal that FIV RNA can be cross-packaged by primate lentivirus particles such as HIV-1 and SIV and vice versa; however, a nonlentivirus particle such as MPMV is unable to package FIV RNA. Interestingly, FIV particles can package MPMV RNA but cannot propagate the vector RNA further for other steps of the retrovirus life cycle. These findings reveal that diverse retroviruses are functionally more similar than originally thought and suggest that upon coinfection of the same host, cross- or copackaging may allow distinct retroviruses to generate chimeric variants with unknown pathogenic potential.
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Affiliation(s)
- M T Browning
- Department of Veterinary Sciences, The University of Texas M.D. Anderson Cancer Center, Bastrop, Texas 78602, USA
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8
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Nakamura K, Miyazawa T, Ikeda Y, Sato E, Nishimura Y, Nguyen NT, Takahashi E, Mochizuki M, Mikami T. Contrastive prevalence of feline retrovirus infections between northern and southern Vietnam. J Vet Med Sci 2000; 62:921-3. [PMID: 10993195 DOI: 10.1292/jvms.62.921] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The prevalence of infections with three feline retroviruses; feline leukemia virus (FeLV), feline immunodeficiency virus (FIV) and feline foamy virus (FeFV), was examined in domestic cats (Felis catus) and leopard cats (Felis bengalensis) in southern Vietnam in 1998. We then compared this data with our previous study in northern Vietnam in 1997. None of the cats had FeLV antigens in both the northern and southern areas. In contrast, there is a great distinction in the seropositivity of FIV. Twenty-two percent of domestic cats had FIV antibodies whereas no FIV positive cats were detected in northern area. FIV may have entered southern Vietnam recently and spread rapidly. FeFV infections were found in both areas, suggesting that FeFV might be present in the cat populations in Vietnam from the earliest time.
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Affiliation(s)
- K Nakamura
- Department of Veterinary Microbiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Japan
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9
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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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10
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Affiliation(s)
- M L Linial
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
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11
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Hutchison JM, Garry FB, Belknap EB, Getzy DM, Johnson LW, Ellis RP, Quackenbush SL, Rovnak J, Hoover EA, Cockerell GL. Prospective characterization of the clinicopathologic and immunologic features of an immunodeficiency syndrome affecting juvenile llamas. Vet Immunol Immunopathol 1995; 49:209-27. [PMID: 8746696 DOI: 10.1016/0165-2427(95)05474-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The clinicopathologic and immunologic features of 15 llamas affected with juvenile llama immunodeficiency syndrome (JLIDS) are described. Healthy adult (n = 10) and juvenile (n = 10) llamas served as controls. JLIDS llamas were characterized by wasting, and clinically apparent, repeated infections were frequently observed. The median age at which a health problem was first perceived was 11.6 months. All 15 affected llamas died or were killed, and JLIDS was confirmed at necropsy. The median duration of illness was 3.5 months. Lymphocyte blastogenesis assays showed suppressed responses (particularly to Staphylococcus sp. Protein A) in JLIDS llamas. No evidence of retroviral infection was detected. Mild, normocytic, normochromic, non-regenerative anemia, low serum albumin concentration and low to low-normal globulin concentrations were typically found on initial clinical evaluation. Lymph node biopsies showed areas of paracortical depletion. All llamas affected with JLIDS had low serum IgG concentrations, pre-vaccination titers against Clostridium perfringens C and D toxoids of < or = 1:100, and no titer increase following vaccination.
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Affiliation(s)
- J M Hutchison
- Department of Clinical Sciences, Colorado State University, Fort Collins 80523, USA
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12
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Bendinelli M, Pistello M, Lombardi S, Poli A, Garzelli C, Matteucci D, Ceccherini-Nelli L, Malvaldi G, Tozzini F. Feline immunodeficiency virus: an interesting model for AIDS studies and an important cat pathogen. Clin Microbiol Rev 1995; 8:87-112. [PMID: 7704896 PMCID: PMC172850 DOI: 10.1128/cmr.8.1.87] [Citation(s) in RCA: 254] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The lentivirus feline immunodeficiency virus (FIV) is a widespread pathogen of the domestic cat that is mainly transmitted through bites, although other means of transmission are also possible. Its prevalence ranges from 1 to 10% in different cat populations throughout the world, thus representing a large reservoir of naturally infected animals. FIV resembles the human immunodeficiency virus (HIV) in many respects. Similarities include the structural features of the virion, the general organization and great variability of the genome, the life cycle in the infected host, and most importantly, the pathogenic potential. Infection is associated with laboratory signs of immunosuppression as well as with a large variety of superinfections, tumors, and neurological manifestations. Our understanding of FIV is steadily improving and is providing important clues to the pathogenesis of immunodeficiency-inducing lentiviruses. The cellular receptor for FIV is different from the feline equivalent of the human CD4 molecule used by HIV; nevertheless, the major hallmark of infection is a progressive loss of CD4+ T lymphocytes as in HIV infection. The mechanisms by which FIV escapes the host's immune responses are being actively investigated. FIV causes lysis of infected T cells and also appears to predispose these cells to apoptosis. Infection of macrophages and other cell types has also been documented. For reasons yet to be understood, antibody-mediated neutralization of fresh FIV isolates is very inefficient both in vitro and in vivo. Vaccination studies have provided some encouraging results, but the difficulties encountered appear to match those met in HIV vaccine development. FIV susceptibility to antiviral agents is similar to that of HIV, thus providing a valuable system for in vivo preclinical evaluation of therapies. It is concluded that in many respects FIV is an ideal model for AIDS studies.
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Affiliation(s)
- M Bendinelli
- Department of Biomedicine, University of Pisa, Italy
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13
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Peri EV, Ponti W, Dall'ara P, Rocchi M, Zecconi A, Bonizzi L. Seroepidemiological and clinical survey of feline immunodeficiency virus infection in northern Italy. Vet Immunol Immunopathol 1994; 40:285-97. [PMID: 8042281 PMCID: PMC7119872 DOI: 10.1016/0165-2427(94)90040-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Four hundred and thirty-nine feline serum samples from cats with different living conditions in the north of Italy were tested for antibodies to feline immunodeficiency virus (FIV) and for antigen of Feline Leukemia Virus by enzyme-linked immunosorbent assay. A Western blot technique was also used on the positive sera in order to confirm the presence of specific antibodies to FIV. The Western blot enabled the detection of a false positive serum. The prevalence of FIV infection in this population was 12.5% and among the seropositive cats a greater proportion was male (74.5%) than female (25.5%). A correlation between the clinical status and the evolution of the pathology is described together with a score based on the severity of the stomatitis in infected cats. The Western blot patterns of positive samples were then compared with the stage of the pathology. Statistical analysis on the distribution of FIV in stray cats, cats with garden and courtyard access and strictly house-confined cats showed a highly significant risk of the infection in the first group.
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Affiliation(s)
- E V Peri
- Istituto di Microbiologia e Immunologia Veterinaria, Università degli Studi di Milano, Italy
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14
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Stone DM, Stephens KE, Doles J. Folate-sensitive and aphidicolin-inducible fragile sites are expressed in the genome of the domestic cat. CANCER GENETICS AND CYTOGENETICS 1993; 65:130-4. [PMID: 8453598 DOI: 10.1016/0165-4608(93)90221-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Peripheral blood lymphocytes from three clinically normal domestic cats were cultured for folate-sensitive and aphidicolin-inducible fragile site expression. Induction of folate-sensitive fragile sites was accomplished by culturing cells with trimethoprim plus caffeine. Chromosomes from all cats expressed both folate-sensitive and aphidicolin-inducible breaks and gaps. There were no significant differences between the two methods of fragile site induction in the percentage of cells expressing chromosome breaks and gaps or the mean number of breaks and gaps per cell. All three cats expressed specific chromosome breaks resembling fragile sites at A1q21-22, A1p22, and B1q32. All three sites were induced by aphidicolin. The sites at A1q21-22 and B1q32 were also induced in folate-deficient medium. This is the first report of the induction of chromosomal fragile sites in a feline species.
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Affiliation(s)
- D M Stone
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman 99164-7040
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15
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Gulino SE. Chromosome abnormalities and oncogenesis in cat leukemias. CANCER GENETICS AND CYTOGENETICS 1992; 64:149-57. [PMID: 1336708 DOI: 10.1016/0165-4608(92)90346-a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Chromosome abnormalities are found in feline leukemia virus (FeLV)-infected tumor cells as well as in tumor cells free of the virus. Three cell lines derived from tumors in the domestic cat (Felis catus), two of thymic origin and one of multicentric lymphoma origin, were analyzed cytogenetically to determine whether the FeLV virus was associated with chromosomal abnormalities in these tumor cell lines. One thymic tumor and the multicentric lymphoma were FeLV infected. The other thymic tumor cell line was FeLV-free. The normal diploid number in the domestic cat is 38. All three cell lines had numerical chromosome abnormalities with modal numbers of 37, 38 (pseudodiploid), and 39, respectively and had consistent structural chromosome abnormalities. Three markers in the virus-free cell line (S markers) were shared with one or the other of the virus-positive cell lines. The two FeLV-positive cell lines did not have S markers in common. The finding of chromosome abnormalities in both the virus-infected and the virus-free cell lines suggests that these abnormalities may be important in oncogenesis. The FeLV virus could not be considered the only causative agent of the abnormalities observed.
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Affiliation(s)
- S E Gulino
- Department of Molecular Biology, University of California, Berkeley 94720
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16
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Abstract
Feline immunodeficiency virus (FIV) has morphological, physical and biochemical characteristics similar to human immunodeficiency virus (HIV), the cause of AIDS in man. However, it is antigenically and genetically distinct from HIV; an antigenic relatedness with equine infectious anaemia virus has been demonstrated. FIV has been molecularly cloned and sequenced. Diagnostic tests are commercially available and attempts at preparing inactivated, subunit and molecularly engineered vaccines are being made in different laboratories. During FIV infection a transient primary illness can be recognized, with fever, neutropenia and lymphadenopathy. After a long period of clinical normalcy a secondary stage is distinguished with signs of an immunodeficiency-like syndrome. The incubation period for this stage can be as long as 5 years, during which gradual impairment of immune function develops. Many FIV-infected cats are presented for the first time showing vague signs of illness: recurrent fevers, emaciation, lack of appetite, lymphadenopathy, anaemia, leucopenia and behavioural changes. Later, the predominant clinical signs observed are chronic stomatitis/gingivitis, enteritis, upper respiratory tract infections, and infections of the skin. Neoplasias, neurological, immunological and haematological disorder are seen in a smaller proportion. The immunodeficiency-like syndrome is progressive over a period of months to years. Concomitant infection with feline leukaemia virus has been shown to accelerate the progression of disease. In vitro, phenotypic mixing between FIV and an endogenous feline oncovirus (RD114) has been demonstrated which leads to a broadening of the cell spectrum of the lentivirus. Bovine immunodeficiency virus (BIV) has been isolated only once, and all attempts to obtain additional isolates have failed; it has been recovered from the leucocytes of cattle with persistent lymphocytosis, lymphadenopathy, lesions in the central nervous system, progressive weakness and emaciation. As with the feline representative, BIV also was found to possess a lentivirus morphology and to encode a reverse transcriptase with Mg++ preference; it replicates and induces syncytia in a variety of embryonic bovine tissues in vitro. Antigenic analyses have demonstrated a conservation of epitopes between the major core protein of BIV and HIV. The original isolate has been molecularly cloned and sequenced. Besides the three large open reading frames (ORFs) comprising the gag, pol, and env genes common to all replication-competent retroviruses, five additional small ORFs were found. Numerous point mutations and deletions were found, mostly in the env-encoding ORF. These data suggest that, within a single virus isolate, BIV displays extensive genomic variation.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- H Egberink
- Institute of Virology, School of Veterinary Medicine, State University of Utrecht, Netherlands
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17
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Abstract
Three immunopathological mechanisms may determine the pathogenesis of viral diseases in animals. (1) A variety of viruses causes transient or prolonged immunosuppression by infecting lymphoreticular tissues and interacting with components of the immune system. (2) In persistent viral infections effective immune responses may result in tissue damage. The mechanisms involved are T-cell-mediated destruction of infected cells and delayed-type hypersensitivity. (3) In a number of viral diseases pathogenic immune complexes are formed when antibodies are produced and react with viral antigen molecules persisting in the host. The selected examples of immune dysfunction are the focus of this review.
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Affiliation(s)
- G Trautwein
- Department of Pathology, School of Veterinary Medicine, Hannover, Germany
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18
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Avrameas A, Guillet JG, Chouchane L, Moraillon A, Sonigo P, Strosberg AD. Localisation of three epitopes of the env protein of feline immunodeficiency virus. Mol Immunol 1992; 29:565-72. [PMID: 1374840 DOI: 10.1016/0161-5890(92)90192-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The envelope protein of the feline immunodeficiency virus (FIV) was analyzed using several epitope prediction programs based on profiles of hydrophilicity, antigenicity, and probability of residues to lie on the protein surface. Tentative homologies with the immunodominant epitope sites in simian virus (SIV) or human immunodeficiency virus (HIV) such as the V3 loop, the site of cleavage between surface envelope protein (SU) and transmembrane envelope protein (TM), and sites of N-glycosylation were thus identified. Five peptides corresponding to potential epitopes were synthesized. Four out of five peptides (P99, P100, P101, P103) were from the FIV surface envelope protein (SU). The last one (P102) was from the FIV transmembrane envelope protein TM. Three of these peptides (P99, P100, and P102) were recognized in ELISA by almost all the sera from infected cats. The peptide from TM (102) was recognized by sera from both naturally infected and inoculated cats, whereas peptides P99 and P100 (from SU) were recognized mainly by sera from naturally infected cats. On the basis of these results we propose that peptides P99, and P100 from SU and P102 from TM constitute epitopes on the FIV env protein.
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Affiliation(s)
- A Avrameas
- Unité d'Immunopharmacologie Moléculaire UPR 0415, CNRS, Paris, France
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19
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Ueland K, Lutz H. Prevalence of feline leukemia virus and antibodies to feline immunodeficiency virus in cats in Norway. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1992; 39:53-8. [PMID: 1316024 DOI: 10.1111/j.1439-0450.1992.tb01137.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Serum samples from 224 Norwegian cats were analyzed for the presence of feline leukemia virus (FeLV) p27 common core antigen, and for antibodies to feline immunodeficiency virus (FIV). Ninety specimens originated from the serum bank at the central referral clinic at the Norwegian College of Veterinary Medicine, which had been collected during the years 1983-1989; 67 sera were submitted from veterinarian practitioners; while 67 sera originated from cats presented for euthanasia. The cats were classified into one "healthy" and one "sick" group. Only 2.2% of sick cats and 1.2% of healthy cats showed FeLV antigenemia, a finding which is lower than which has been reported from many other countries. The prevalence of FIV antibodies was 10.1% in sick cats and 5.9% in healthy cats. Antibodies to FIV was most prevalent in male cats (14.7%) than in female cats (2.1%), and more prevalent among domestic cats (12.0%) compared to pedigree cats (2.4%). Antibodies to FIV in the cats demonstrated increasing prevalence with increasing age. It may be concluded that FeLV causes minor problems in Norwegian cats, while FIV is present in a similar prevalence to what is reported from other countries.
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Affiliation(s)
- K Ueland
- National Veterinary Institute, Oslo, Norway
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