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Fandiño S, Gomez-Lucia E, Benítez L, Doménech A. Comparison of Endogenous Alpharetroviruses (ALV-like) across Galliform Species: New Distant Proviruses. Microorganisms 2023; 12:86. [PMID: 38257913 PMCID: PMC10820513 DOI: 10.3390/microorganisms12010086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 12/22/2023] [Accepted: 12/25/2023] [Indexed: 01/24/2024] Open
Abstract
The Genus Alpharetrovirus contains viruses pathogenic mainly for chickens, forming the Avian Sarcoma and Leukosis Virus group (ASLV). Cells of most Galliform species, besides chickens, contain genetic elements (endogenous retroviruses, ERVs) that could recombine with other alpharetroviruses or express proteins, complementing defective ASLV, which may successfully replicate and cause disease. However, they are quite unknown, and only ALV-F, from ring-necked pheasants, has been partially published. Upon scrutiny of 53 genomes of different avian species, we found Alpharetrovirus-like sequences only in 12 different Galliformes, including six full-length (7.4-7.6 Kbp) and 27 partial sequences. Phylogenetic studies of the regions studied (LTR, gag, pol, and env) consistently resulted in five almost identical clades containing the same ERVs: Clade I (presently known ASLVs); Clade II (Callipepla spp. ERVs); Clade IIIa (Phasianus colchicus ERVs); Clade IIIb (Alectoris spp. ERVs); and Clade IV (Centrocercus spp. ERVs). The low pol identity scores suggested that each of these Clades may be considered a different species. ORF analysis revealed that putatively encoded proteins would be very similar in length and domains to those of other alpharetroviruses and thus potentially functional. This will undoubtedly contribute to better understanding the biology of defective viruses, especially in wild Galliformes, their evolution, and the danger they may represent for other wild species and the poultry industry.
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Affiliation(s)
- Sergio Fandiño
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (S.F.); (A.D.)
- Department of Genetics, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid (UCM), C. de José Antonio Novais 12, 28040 Madrid, Spain;
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
| | - Esperanza Gomez-Lucia
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (S.F.); (A.D.)
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
| | - Laura Benítez
- Department of Genetics, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid (UCM), C. de José Antonio Novais 12, 28040 Madrid, Spain;
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
| | - Ana Doménech
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (S.F.); (A.D.)
- Research Group, “Animal Viruses” of Complutense University of Madrid, 28040 Madrid, Spain
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Dou J, Wang Z, Li L, Lu Q, Jin X, Ling X, Cheng Z, Zhang T, Shao H, Zhai X, Luo Q. A Multiplex Quantitative Polymerase Chain Reaction for the Rapid Differential Detection of Subgroups A, B, J, and K Avian Leukosis Viruses. Viruses 2023; 15:1789. [PMID: 37766196 PMCID: PMC10535029 DOI: 10.3390/v15091789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/16/2023] [Accepted: 08/21/2023] [Indexed: 09/29/2023] Open
Abstract
Avian leukosis (AL), caused by avian leukosis virus (ALV), is a contagious tumor disease that results in significant economic losses for the poultry industry. Currently, ALV-A, B, J, and K subgroups are the most common in commercial poultry and cause possible coinfections. Therefore, close monitoring is necessary to avoid greater economic losses. In this study, a novel multiplex quantitative polymerase chain reaction (qPCR) assay was developed to detect ALV-A, ALV-B, ALV-J, and ALV-K with limits of detection of 40, 11, 13.7, and 96 copies/µL, respectively, and no cross-reactivity with other ALV subtypes and avian pathogens. We detected 852 cell cultures inoculated with clinical samples using this method, showing good consistency with conventional PCR and ELISA. The most prevalent ALV strain in Hubei Province, China, was still ALV-J (11.74%). Although single infections with ALV-A, ALV-B, and ALV-K were not found, coinfections with different subgroup strains were identified: 0.7% for ALV-A/J, 0.35% for ALV-B/J, 0.25% for ALV-J/K, and 0.12% for ALV-A/B/K and ALV-A/B/J. Therefore, our novel multiplex qPCR may be a useful tool for molecular epidemiology, clinical detection of ALV, and ALV eradication programs.
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Affiliation(s)
- Junfeng Dou
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
- Department of Animal Medicine, College of Life Science and Food Engineering, Hebei University of Engineering, Handan 056038, China
| | - Zui Wang
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
| | - Li Li
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
| | - Qin Lu
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
| | - Xinxin Jin
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
| | - Xiaochun Ling
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
| | - Zhengyu Cheng
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Tengfei Zhang
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
| | - Huabin Shao
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
| | - Xinguo Zhai
- Department of Animal Medicine, College of Life Science and Food Engineering, Hebei University of Engineering, Handan 056038, China
| | - Qingping Luo
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis (Ministry of Agriculture and Rural Affairs), Institute of Animal Husbandry and Veterinary, Hubei Academy of Agricultural Sciences, Special One, Nanhuyaoyuan, Hongshan District, Wuhan 430064, China; (J.D.); (Z.W.); (L.L.); (Q.L.); (X.J.); (X.L.); (H.S.)
- Hubei Hongshan Laboratory, Wuhan 430064, China
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Fandiño S, Gomez-Lucia E, Benítez L, Doménech A. Avian Leukosis: Will We Be Able to Get Rid of It? Animals (Basel) 2023; 13:2358. [PMID: 37508135 PMCID: PMC10376345 DOI: 10.3390/ani13142358] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Avian leukosis viruses (ALVs) have been virtually eradicated from commercial poultry. However, some niches remain as pockets from which this group of viruses may reemerge and induce economic losses. Such is the case of fancy, hobby, backyard chickens and indigenous or native breeds, which are not as strictly inspected as commercial poultry and which have been found to harbor ALVs. In addition, the genome of both poultry and of several gamebird species contain endogenous retroviral sequences. Circumstances that support keeping up surveillance include the detection of several ALV natural recombinants between exogenous and endogenous ALV-related sequences which, combined with the well-known ability of retroviruses to mutate, facilitate the emergence of escape mutants. The subgroup most prevalent nowadays, ALV-J, has emerged as a multi-recombinant which uses a different receptor from the previously known subgroups, greatly increasing its cell tropism and pathogenicity and making it more transmissible. In this review we describe the ALVs, their different subgroups and which receptor they use to infect the cell, their routes of transmission and their presence in different bird collectivities, and the immune response against them. We analyze the different systems to control them, from vaccination to the progress made editing the bird genome to generate mutated ALV receptors or selecting certain haplotypes.
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Affiliation(s)
- Sergio Fandiño
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain
- Department of Genetics, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid (UCM), C. de José Antonio Novais 12, 28040 Madrid, Spain
- Research Group, "Animal Viruses" of Complutense University of Madrid, 28040 Madrid, Spain
| | - Esperanza Gomez-Lucia
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain
- Research Group, "Animal Viruses" of Complutense University of Madrid, 28040 Madrid, Spain
| | - Laura Benítez
- Department of Genetics, Physiology and Microbiology, Faculty of Biological Sciences, Complutense University of Madrid (UCM), C. de José Antonio Novais 12, 28040 Madrid, Spain
- Research Group, "Animal Viruses" of Complutense University of Madrid, 28040 Madrid, Spain
| | - Ana Doménech
- Department of Animal Health, Veterinary Faculty, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain
- Research Group, "Animal Viruses" of Complutense University of Madrid, 28040 Madrid, Spain
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Borodin AM, Emanuilova ZV, Smolov SV, Ogneva OA, Konovalova NV, Terentyeva EV, Serova NY, Efimov DN, Fisinin VI, Greenberg AJ, Alekseev YI. Eradication of avian leukosis virus subgroups J and K in broiler cross chickens by selection against infected birds using multilocus PCR. PLoS One 2022; 17:e0269525. [PMID: 35749432 PMCID: PMC9231750 DOI: 10.1371/journal.pone.0269525] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 05/23/2022] [Indexed: 12/04/2022] Open
Abstract
The avian leukosis virus (ALV) is a serious threat to sustainable and economically viable commercial poultry management world-wide. Active infections can result in more than 20% flock loss, resulting in significant economic damage. ALV detection and elimination from flocks and breeding programs is complicated by high sequence variability and the presence of endogenous virus copies which show up as false positives in assays. Previously-developed approaches to virus detection are either too labor-intensive to implement on an industrial scale or suffer from high false negative or positive rates. We developed a novel multi-locus multiplex quantitative real-time PCR system to detect viruses belonging to the J and K genetic subgroups that are particularly prevalent in our region. We used this system to eradicate ALV from our broiler breeding program comprising thousands of individuals. Our approach can be generalized to other ALV subgroups and other highly genetically diverse pathogens.
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Affiliation(s)
- Alexander M. Borodin
- Breeding and Genetic Center Smena, Ministry of Science and Higher Education of the Russian Federation, Bereznyaki, Russia
- Institute of Medical and Biological Research, Nizhnii Novgorod, Russia
| | - Zhanna V. Emanuilova
- Breeding and Genetic Center Smena, Ministry of Science and Higher Education of the Russian Federation, Bereznyaki, Russia
| | - Sergei V. Smolov
- Breeding and Genetic Center Smena, Ministry of Science and Higher Education of the Russian Federation, Bereznyaki, Russia
| | - Olga A. Ogneva
- Breeding and Genetic Center Smena, Ministry of Science and Higher Education of the Russian Federation, Bereznyaki, Russia
| | | | | | - Natalia Y. Serova
- All-Russian Research Veterinary Institute of Poultry Science Branch of the Federal Scientific Center All-Russian Research and Technological Poultry Institute Russian Academy of Science, St. Petersburg, Russia
| | - D. N. Efimov
- Federal Scientific Center All-Russian Research and Technological Poultry Institute Russian Academy of Science, Sergiev Posad, Russia
| | - V. I. Fisinin
- Federal Scientific Center All-Russian Research and Technological Poultry Institute Russian Academy of Science, Sergiev Posad, Russia
| | | | - Yakov I. Alekseev
- Syntol LLC, Moscow, Russia
- Institute for Analytical Instrumentation Russian Academy of Science, St. Petersburg, Russia
- * E-mail: (AJG); (YIA)
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Gifford R, Kabat P, Martin J, Lynch C, Tristem M. Evolution and distribution of class II-related endogenous retroviruses. J Virol 2005; 79:6478-86. [PMID: 15858031 PMCID: PMC1091674 DOI: 10.1128/jvi.79.10.6478-6486.2005] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Endogenous retroviruses (ERVs) are widespread in vertebrate genomes and have been loosely grouped into "classes" on the basis of their phylogenetic relatedness to the established genera of exogenous retroviruses. Four of these genera-the lentiviruses, alpharetroviruses, betaretroviruses, and deltaretroviruses-form a well-supported clade in retroviral phylogenies, and ERVs that group with these genera have been termed class II ERVs. We used PCR amplification and sequencing of retroviral fragments from more than 130 vertebrate taxa to investigate the evolution of the class II retroviruses in detail. We confirm that class II retroviruses are largely confined to mammalian and avian hosts and provide evidence for a major novel group of avian retroviruses, and we identify additional members of both the alpha- and the betaretrovirus genera. Phylogenetic analyses demonstrated that the avian and mammalian viruses form distinct monophyletic groups, implying that interclass transmission has occurred only rarely during the evolution of the class II retroviruses. In contrast to previous reports, the lentiviruses clustered as sister taxa to several endogenous retroviruses derived from rodents and insectivores. This topology was further supported by the shared loss of both the class II PR-Pol frameshift site and the class II retrovirus G-patch domain.
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Affiliation(s)
- Robert Gifford
- Division of Virology, Windeyer Institute of Medical Sciences, 46 Cleveland St., London W1F 4JF, United Kingdom.
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Himly M, Foster DN, Bottoli I, Iacovoni JS, Vogt PK. The DF-1 chicken fibroblast cell line: transformation induced by diverse oncogenes and cell death resulting from infection by avian leukosis viruses. Virology 1998; 248:295-304. [PMID: 9721238 DOI: 10.1006/viro.1998.9290] [Citation(s) in RCA: 347] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
DF-1 is a continuous cell line of chicken embryo fibroblasts. The cells are free of endogenous sequences related to avian sarcoma and leukosis viruses and have normal fibroblastic morphology. DF-1 cells support the replication of avian retroviruses; diverse oncogenes induce foci of oncogenic transformation on monolayers of DF-1, and avian leukosis viruses of envelope subgroups B, D, and C induce cell death and form plaques. The new cell line will greatly facilitate studies on oncogenic transformation and cell killing by avian viruses.
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Affiliation(s)
- M Himly
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California, 92037, USA
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Simon MC, Neckameyer WS, Hayward WS, Smith RE. Genetic determinants of neoplastic diseases induced by a subgroup F avian leukosis virus. J Virol 1987; 61:1203-12. [PMID: 3029416 PMCID: PMC254082 DOI: 10.1128/jvi.61.4.1203-1212.1987] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Two subgroup F avian leukosis viruses, ring-necked pheasant virus (RPV) and RAV-61, were previously shown to induce a high incidence of a fatal proliferative disorder in the lungs of infected chickens. These lung lesions, termed angiosarcomas, appear rapidly (4 to 5 weeks after infection), show no evidence of proto-oncogene activation by proviral integration, and are not induced by avian leukosis viruses belonging to other subgroups. To identify the viral sequences responsible for induction of these tumors, we constructed recombinant viruses by exchanging genomic segments of molecularly cloned RPV with those of a subgroup A leukosis virus, UR2AV. The ability to induce rapid lung tumors segregated only with the env sequences of RPV; the long terminal repeat of RPV was not required. However, recombinants carrying both env and long terminal repeat sequences of RPV induced lung tumors with a shorter latency. In several cases, recombinant viruses exhibited pathogenic properties differing from those of either parental virus. Recombinants carrying the gag-pol region of RPV and the env gene of UR2AV induced a high incidence of a muscle lesion termed infiltrative intramuscular fibromatosis. One recombinant, EU-8, which carries the gag-pol and LTR sequences of RPV, and the env gene of UR2AV, induced lymphoid leukosis after an unusually short latent period. The median time of death from lymphoid leukosis was 6 to 7 weeks after infection with EU-8 compared with approximately 5 months for UR2AV.
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Troesch CD, Vogt PK. An endogenous virus from Lophortyx quail is the prototype for envelope subgroup 1 of avian retroviruses. Virology 1985; 143:595-602. [PMID: 2998026 DOI: 10.1016/0042-6822(85)90397-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Abstract
Subgroup F avian leukosis viruses, such as RAV-61 and ring-necked pheasant virus, are recombinants between exogenous chicken retroviruses and endogenous pheasant viruses and contain new envelope (env) genes. Chickens infected as 10-day-old embryos with subgroup F viruses develop fibrosarcomas, nephroblastomas, osteopetrosis, B-cell lymphomas, and a high incidence of a proliferative disorder involving the lung. Fibrosarcomas, nephroblastomas, and lymphomas appear after long latent periods (3 to 12 months). They contain discrete virus-cell junction fragments and are therefore clonal outgrowths of a single infected cell. Two ring-necked pheasant virus-induced B-cell lymphomas and an adenocarcinoma of the abdomen contained proviruses integrated at the c-myc locus and elevated levels of myc mRNA. At least four of the fibrosarcomas appeared to contain proviruses integrated at a common site, suggesting that a specific cellular gene may be involved in these tumors. The host gene has not been identified, however; 16 different oncogene probes failed to hybridize to fibrosarcoma junction fragments. In contrast to these neoplasms, lung lesions appeared rapidly (4 to 5 weeks), showed no evidence of clonality, and lacked long terminal repeat-initiated transcripts other than viral 35S and 21S mRNA. We conclude, therefore, that subgroup F retroviruses induce the proliferative disorder of the lung by a different mechanism.
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Abstract
Rous-associated virus 7 (RAV-7) is a subgroup C avian leukosis virus which does not transform cells in vitro or carry an oncogene. When injected into 1-day-old hatched chicks, RAV-7 causes a low incidence of lymphoid leukosis after a latent period of several months. In contrast, infection of 10-day-old chicken embryos with RAV-7 leads to a disease syndrome characterized by stunting, obesity, atrophy of the bursa and the thymus, high triglyceride and cholesterol levels, reduced thyroxine levels, and increased insulin levels (Carter et al., Infect. Immun. 39:410-422, 1983; J.K. Carter and R.E. Smith, Infect. Immun. 40:795-805, 1983). Histopathological examination of tissues from affected chicks revealed an accumulation of lipid in the liver and an extensive infiltration of the thyroid and pancreas by lymphoblastoid cells. In the present investigation, the subgroup specificity of this syndrome was investigated. Other subgroup C avian leukosis viruses (transformation-defective B77, transformation-defective Prague C strain of Rous sarcoma virus, and RAV-49) caused stunting, infiltration of the thyroid and pancreas, increased liver weights, decreased thyroxine levels, and increased insulin levels, but they did not cause a uniform, profound increase in triglyceride and cholesterol levels. Avian leukosis viruses of subgroup A [myeloblastosis-associated virus 1 causing osteopetrosis [MAV-1(O)] and RAV-1], subgroup B [MAV-2(O), MAV-2 causing nephroblastoma [MAV-2(N)], and RAV-2], subgroup D (RAV-50), and subgroup F (ring-necked pheasant virus and RAV-61) did not cause a syndrome identical to that induced by RAV-7. All of the viruses examined induced some stunting and a reduction in thyroxine levels which correlated with the stunting. The two subgroup F viruses caused an infiltration of the thyroid which may have been secondary to severe lung involvement. We conclude that the RAV-7 syndrome is unique, particularly in the induction of a hyperlipidemia.
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Halpern MS, Ewert DL, Flores LJ, Fujita DJ, Aldrich CE, Mason WS. Sarcoma growth in 15I5 x 7(2) chickens infected with avian sarcoma viruses of subgroup B or G. Virology 1984; 134:472-6. [PMID: 6100579 DOI: 10.1016/0042-6822(84)90315-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A comparative study was made of sarcoma growth in 15I5 x 7(2) chickens infected in the wing web at 4 weeks of age with strains of subgroup B or G avian sarcoma viruses. Infection with sarcoma viruses of either subgroup B or G resulted in the formation of progressive wing web sarcomas at the site of inoculation. The survival times of the subgroup G virus-infected chickens were generally at least twice as great as the survival times of the subgroup B virus-infected chickens, which averaged 6-9 weeks postinoculation. At 5 weeks postinfection, a significantly higher titer of virus neutralizing antibody was detected in the subgroup G virus-infected chickens. Necropsy indicated that a high percentage of subgroup B virus-infected chickens exhibited fibrosarcomas at sites distal to the primary wing web sarcomas, whereas only a small percentage of subgroup G virus-infected chickens exhibited distal sarcomas. The results further indicated that the viral env gene is a determinant of the pattern of distal sarcoma formation.
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Abstract
Ring-necked pheasant virus, an avian leukosis virus, when injected into 10-day old chick embryos, caused angiosarcomas in the lungs of infected chickens within a short time. Angiosarcomas appeared as localized foci of proliferating cells in the lungs as early as 2 weeks posthatch, and by 6 weeks, the lungs of the infected chickens were frequently filled with tumor cells. Between 3 and 10 weeks of age, 80% of infected chickens died of the angiosarcomas; the 20% which lived 8 weeks or longer had small lung lesions and also developed fibrosarcomas, osteopetrosis, nephroblastoma, and lymphoid leukosis. Chickens with lung tumors were cyanotic, had breathing difficulty, and had packed cell volumes in excess of 50%. Other changes not necessarily correlated with lung tumor mass were stunting, lymphoid organ involution, and profuse diarrhea. Ring-necked pheasant virus has a genome RNA of 8.2 kb. This observation, together with its replication and disease induction after repeated plaque purification, suggests that ring-necked pheasant virus is a replication-competent avian retrovirus. Therefore, our results suggest that ring-necked pheasant virus is an avian leukosis virus which causes angiosarcomas rapidly at high incidence and which, therefore, may induce this type of tumor by a mechanism different from the induction of sarcomas by avian sarcoma viruses.
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Halpern MS, Deery DT, Flores LJ, Fujita DJ, Mason WS. Differential reactivity of serum antibody from tumor-bearing 15I5 X 7(2) chickens for cross-reactive species of endogenous retroviral envelope glycoprotein. Virology 1983; 124:318-29. [PMID: 6297160 DOI: 10.1016/0042-6822(83)90348-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Experiments were undertaken to determine if the sera of avian sarcoma virus-infected 15I5 X 7(2) chickens exhibit antibody reactivity for species of endogenous retroviral envelope glycoprotein expressed in 15I5 X 7(2) fibroblasts. Two viruses were used for infection of the 15I5 X 7(2) chickens, Pr-A and cl. 85; the envelope glycoprotein of Pr-A, but not of cl. 85, is antigenically cross-reactive with 15I5 X 7(2) endogenous retroviral envelope glycoprotein. Both the Pr-A and cl. 85-infected 15I5 X 7(2) chickens exhibited serum antibody reactivity for the envelope glycoprotein of the endogenous retrovirus RAV-O. In contrast, neither group of infected chickens exhibited detectable serum antibody reactivity for a distinct species of endogenous retroviral envelope glycoprotein, one which though antigenically cross-reactive with the envelope glycoprotein of RAV-O is expressed to much higher levels in 15I5 X 7(2) fibroblasts. Possible mechanisms to account for the observed pattern of antibody reactivity are discussed.
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Bister K, Ramsay GM, Hayman MJ. Deletions within the transformation-specific RNA sequences of acute leukemia virus MC29 give rise to partially transformation-defective mutants. J Virol 1982; 41:754-66. [PMID: 6284968 PMCID: PMC256813 DOI: 10.1128/jvi.41.3.754-766.1982] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The viral RNAs of three nonconditional mutants of avian myelocytomatosis virus MC29 were analyzed. These mutants, which were originally isolated from the quail producer line Q10 and were designated 10A, 10C, and 10H, have lost most of the ability to transform hematopoietic cells in vitro and to induce tumors in vivo, but they still transform cultured fibroblasts with the same efficiency as wild-type (wt) MC29. Electrophoretic analyses showed that the mutant genomic RNAs were smaller than the 5.7-kilobase genome of wt MC29; the genomes of mutants 10A, 10C, and 10H were about 5.5, 5.3, and 5.1 kilobases long, respectively. Analyses of the transformation-specific sequences of these mutant RNAs by a combination of T(1) oligonucleotide fingerprinting and hybridization with cDNA from the transformation-specific sequences myc of wt MC29 or competition hybridization including wt MC29 RNA revealed that deletions of myc-specific sequences had occurred. The deletions in all three mutants overlapped, since they all had lost one particular myc-specific oligonucleotide. In agreement with the size of the genomic RNAs, mutants 10C and 10H had lost two additional myc oligonucleotides, and mutant 10A contained a modified myc oligonucleotide. The locations of the deletions were deduced from comparisons with previously established oligonucleotide maps of several members of the MC29 subgroup of acute leukemia viruses and by hybridization of wt and mutant RNAs to molecularly cloned subgenomic fragments of wt MC29 proviral DNA, representing the 5' and 3' domains of the myc sequence. We found that the deleted sequences represented overlapping internal segments of the myc sequence and that the borders of myc with the partial complements of the virion genes gag and env appeared to be conserved in mutant and wt MC29 RNAs. The correlation between the altered transforming potential for hematopoietic cells and the partial deletion of myc in the mutant RNAs provided direct genetic evidence for the involvement of myc in oncogenesis. However, the unaffected efficiency of these mutants in fibroblast transformation suggested that the deleted sequences are not essential for the fibroblast-transforming potential of the onc gene of MC29.
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18
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Schmidt EV, Keene JD, Linial M, Smith RE. Association of 3' terminal RNA sequences with avian leukosis viruses causing a high incidence of osteopetrosis. Virology 1982; 116:163-80. [PMID: 6278705 DOI: 10.1016/0042-6822(82)90411-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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19
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Abstract
LA3382 is a temperature-sensitive replication-defective mutant of Rous sarcoma virus that contains four active mutations. In this study we performed experiments to determine the biochemical defect that blocks the synthesis of infections virus late in the replication cycle. At the nonpermissive temperature (41 degrees C) cells infected with LA3382 synthesized virus particles which were noninfectious and exhibited significant reductions in the amounts of gp85 and gp37 present in the virions. An analysis of the intracellular viral polypeptides indicated that the precursor of the viral glycoproteins (Pr95) were synthesized normally but underwent cleavage at a reduced rate at the restrictive temperature. Pr95 did not accumulate in infected cells ans was inserted into mutant virions at 41 degrees C; however, Pr95 was cleaved in such a way that gp85 was released from the viruses and could be detected in the supernatant medium by immunoprecipitation. The virus-free glycoprotein was indistinguishable from wild-type gp85 and may have been released due to an anomalous cleavage. Pulse-chase experiments also indicated that the Pr180 polyprotein precursor of the reverse transcriptase was cleaved to the active form of the enzyme more slowly at 41 degrees C in LA3382-infected cells. This accounted for the twofold lower level of polymerase activity found in mutant virions at 41 degrees C, defect which probably did not account for the observed 20- to 50-fold reduction in infectivity. Furthermore, the replication defect was not complemented by an env deletion mutant Rous sarcoma virus [RSV(-)[, which should complement a pol defect. Therefore, we conclude that the major lesion that impairs replication in LA3382 is within the env gene.
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20
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Breitman ML, Neil JC, Moscovici C, Vogt PK. The pathogenicity and defectiveness of PRCII: a new type of avian sarcoma virus. Virology 1981; 108:1-12. [PMID: 6168093 DOI: 10.1016/0042-6822(81)90522-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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21
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Spector DH. Gene-specific probes for avian retroviruses. Curr Top Microbiol Immunol 1981; 91:41-80. [PMID: 6273070 DOI: 10.1007/978-3-642-68058-8_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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22
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Lai MM, Hu SS, Vogt PK. Avian erythroblastosis virus: transformation-specific sequences form a contiguous segment of 3.25 kb located in the middle of the 6-kb genome. Virology 1979; 97:366-77. [PMID: 224587 DOI: 10.1016/0042-6822(79)90347-7] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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23
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24
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25
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Meyers P, Ritts GD, Heise JM, Qualtiere LF. Limited host range of avian tumor viruses on pigeon cells. Virology 1978; 90:162-5. [PMID: 213893 DOI: 10.1016/0042-6822(78)90345-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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26
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Hu SS, Moscovici C, Vogt PK. The defectiveness of Mill Hill 2, a carcinoma-inducing avian oncovirus. Virology 1978; 89:162-78. [PMID: 210569 DOI: 10.1016/0042-6822(78)90049-1] [Citation(s) in RCA: 80] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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27
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28
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Levinson W, Oppermann H, Rubenstein P, Jackson J. Host range restriction of vesicular stomatitis virus on duck embryo cells. Virology 1978; 85:612-6. [PMID: 208241 DOI: 10.1016/0042-6822(78)90466-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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29
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30
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Robinson HL. Inheritance and expression of chicken genes that are related to avian leukosis sarcoma virus genes. Curr Top Microbiol Immunol 1978; 83:1-36. [PMID: 215385 DOI: 10.1007/978-3-642-67087-9_1] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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31
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Wang LH, Duesberg PH, Robins T, Yokota H, Vogt PK. The terminal oligonucleotides of avian tumor virus RNAs are genetically linked. Virology 1977; 82:472-92. [PMID: 199998 DOI: 10.1016/0042-6822(77)90020-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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32
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Bister K, Hayman MJ, Vogt PK. Defectiveness of avian myelocytomatosis virus MC29: isolation of long-term nonproducer cultures and analysis of virus-specific polypeptide synthesis. Virology 1977; 82:431-48. [PMID: 199997 DOI: 10.1016/0042-6822(77)90017-4] [Citation(s) in RCA: 229] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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33
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Chen YC, Hayman MJ, Vogt PK. Properties of mammalian cells transformed by temperature-sensitive mutants of avian sarcoma virus. Cell 1977; 11:513-21. [PMID: 195741 DOI: 10.1016/0092-8674(77)90069-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fibroblasts from European field vole (Microtus agrestis) and from normal rat kidney (NRK) have been infected by avian sarcoma virus mutants which are temperature-sensitive for the maintenance of transformation. These cells are transformed at 33 degrees C, but show normal cell characteristics in morphology, colony formation in agar, saturation density, sugar uptake and membrane proteins at 39 degrees C and 40 degrees C, the nonpermissive temperatures. Ts mutant virus was rescued from most of the ts transformed cell lines. NRK cells infected by avian sarcoma virus ts mutants and kept at the nonpermissive temperature can be transformed by wild-type avian sarcoma virus. The susceptibility of the temperature-sensitive NRK lines to this transformation is higher than the susceptibility of uninfected NRK at either permissive or nonpermissive temperature.
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34
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Vogt PK, Spencer JL, Okazaki W, Witter RL, Crittenden LB. Phenotypic mixing between reticuloendotheliosis virus and avian sarcoma viruses. Virology 1977; 80:127-35. [PMID: 195392 DOI: 10.1016/0042-6822(77)90385-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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35
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Tal J, Kung HJ, Varmus HE, Bishop JM. Characterization of DNA complementary to nucleotide sequences adjacent to poly(A) at the 3'-terminus of the avian sarcoma virus genome. Virology 1977; 79:183-97. [PMID: 194400 DOI: 10.1016/0042-6822(77)90344-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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36
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Friedrich R, Kung HJ, Baker B, Varmus HE, Goodman HM, Bishop JM. Characterization of DNA complementary to nucleotide sequences at the 5'-terminus of the avian sarcoma virus genome. Virology 1977; 79:198-215. [PMID: 194401 DOI: 10.1016/0042-6822(77)90345-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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37
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Kurth R, Bosch V, Bolognesi DP. Polypeptides of endogenous avian C-type viruses: their detection in the plasma membrane of normal and infected cells. Virology 1977; 78:511-21. [PMID: 68617 DOI: 10.1016/0042-6822(77)90127-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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38
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Moscovici C, Moscovici MG, Jimenez H, Lai MM, Hayman MJ, Vogt PK. Continuous tissue culture cell lines derived from chemically induced tumors of Japanese quail. Cell 1977; 11:95-103. [PMID: 194709 DOI: 10.1016/0092-8674(77)90320-8] [Citation(s) in RCA: 356] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Several continuous tissue culture cell lines were established from methylcholanthrene-induced fibrosarcomas of Japanese quail. The lines consist either of fibroblastic elements, round refractile cells or polygonal cells. They show transformed characteristics in agar colony formation and hexose uptake, and most are tumorigenic. Their cloning efficiency in plastic dishes is not increased over that of normal quail embryo fibroblasts. The quail tumor cell lines do not produce endogenous avian oncoviruses and fail to complement the Bryan high titer strain of Rous sarcoma virus; those tested lack the p27 protein of avian oncoviruses. Most of the cell lines are susceptible to subgroup A avian sarcoma viruses, but are relatively resistant to viruses of subgroups C, E and F as compared to normal quail embryo fibroblasts.
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39
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40
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Guntaka RV, Richards OC, Shank PR, Kung HJ, Davidson N. Covalently closed circular DNA of avian sarcoma virus: purification from nuclei of infected quail tumor cells and measurement by electron microscopy and gel electrophoresis. J Mol Biol 1976; 106:337-57. [PMID: 185393 DOI: 10.1016/0022-2836(76)90090-5] [Citation(s) in RCA: 113] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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41
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42
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Moscovici C, Chi D, Gazzolo L, Moscovici MG. A study of plaque formation with avian RNA tumor viruses. Virology 1976; 73:181-9. [PMID: 183351 DOI: 10.1016/0042-6822(76)90072-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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43
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Stehelin D, Guntaka RV, Varmus HE, Bishop JM. Purification of DNA complementary to nucleotide sequences required for neoplastic transformation of fibroblasts by avian sarcoma viruses. J Mol Biol 1976; 101:349-65. [PMID: 176368 DOI: 10.1016/0022-2836(76)90152-2] [Citation(s) in RCA: 213] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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44
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Calneck BW, Payne LN. Lack of correlation between Marena tumor induction and expression of endogenous avian RNA tumor virus genome. Int J Cancer 1976; 17:235-44. [PMID: 175029 DOI: 10.1002/ijc.2910170212] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Infection with Marek's disease virus (MDV) and subsequent tumor development failed to induce the expression of endogenous avian RNA tumor virus genome in Line-15I and Line-7 chickens which lacked such expression at 1 day of age. Titers of avian leukosis virus (ALV) group-specific (gs) antigen detected by the COFAL test and expression of chick helper factor (chf) activity remained relatively constant in birds which expressed these genome functions at hatching time. Endogenous ALV belonging to the E-subgroup was isolated from two of 50 birds; both were controls not exposed to MDV. There was no correlation between expression of ALV genome (gs or chf) at 1 day of age and the rate of tumor development subsequent ot MDV infection. It was concluded that MDV infection can induce tumors without the participation of endogenous ALV genome.
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45
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Kurth R. Surface alterations in cells infected by avian leukosis-sarcoma viruses. BIOMEMBRANES 1976; 8:167-233. [PMID: 183843 DOI: 10.1007/978-1-4684-9087-9_5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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46
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Robinson HL, Swanson CA, Hruska JF, Crittenden LB. Production of unique C-type viruses by chicken cells grown in bromodeoxyuridine. Virology 1976; 69:63-74. [PMID: 54982 DOI: 10.1016/0042-6822(76)90194-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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47
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Hill M, Hillova J. Genetic transformation of animal cells with viral DNA of RNA tumor viruses. Adv Cancer Res 1976; 23:237-97. [PMID: 58548 DOI: 10.1016/s0065-230x(08)60548-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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48
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Zarling DA. Spontaneous mutation of RNA tumour viruses. LA RICERCA IN CLINICA E IN LABORATORIO 1976; 6:13-9. [PMID: 183260 DOI: 10.1007/bf02901485] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
There are 2 categories of spontaneously occurring avian and mammalian RNA tumour virus mutants: conditional and non-conditional. 1) Conditional mutants are able to replicate in or transform cells only under certain physiological conditions or in certain cells. RNA tumour virus temperature-sensitive mutants, focus-morphology mutants, and host range mutants are spontaneously formed. Some of these conditional mutants probably arise by point mutations in the viral genome. 2) Non-conditional mutants have genetic lesions that render them inactive under all conditions. There are non-conditional spontaneous RNA tumour virus mutants that are missing either the virion envelope glycoprotein or both the envelope glycoprotein and the virion DNA polymerase. These mutants cannot replicate or transform cells. Other spontaneous non-conditional mutants can replicate but are defective in their ability to transform fibroblastoid cells. These spontaneous transformation-defective mutants can have deletions in 10-20% of the genomic RNA. Conditional mutants with an altered host range occur at a high rate of approximately 1 mutation/50 infected cell generations during DNA-to-DNA information transfer. This type of conditional mutation requires cell replication but does not occur frequently either during the original synthesis of viral DNA (RNA-to-DNA information transfer) or during the transcription of progeny viral RNA from the (RNA-to-DNA information transfer) or during the transcription of progeny viral RNA from the DNA (DNA-to-RNA information transfer). Temperature-sensitive and focus-morphology mutants also have a high rate of spontaneous formation. Non-conditional mutants missing the viral envelope glycoprotein, DNA polymerase, or transformation gene, also appear to be spontaneously formed at a high rate. Normal avian and mammalian cells contain RNA tumour virus-related genes in their DNA. It is hypothesized that these endogenous RNA tumour virus-related genes in normal cells also have a high rate of spontaneous mutation and are involved in neoplastic processes.
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49
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Gazzolo L, Moscovici MG, Moscovici C, Vogt PK. Susceptibility and resistance of chicken macrophages to avian RNA tumor viruses. Virology 1975; 67:553-65. [PMID: 171840 DOI: 10.1016/0042-6822(75)90455-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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50
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Rohrschneider L, Bauer H, Bolognesi DP. Group-specific antigenic determinants of the large envelope glycoprotein of avian oncornaviruses. Virology 1975; 67:234-41. [PMID: 51537 DOI: 10.1016/0042-6822(75)90420-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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