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Cousens C, Meehan J, Collie D, Wright S, Chang Z, Todd H, Moore J, Grant L, Daniel CR, Tennant P, Ritchie A, Nixon J, Proudfoot C, Guido S, Brown H, Gray CD, MacGillivray TJ, Clutton RE, Greenhalgh SN, Gregson R, Griffiths DJ, Spivey J, Storer N, Eckert CE, Gray M. Tracking Ovine Pulmonary Adenocarcinoma Development Using an Experimental Jaagsiekte Sheep Retrovirus Infection Model. Genes (Basel) 2024; 15:1019. [PMID: 39202379 PMCID: PMC11353984 DOI: 10.3390/genes15081019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 07/23/2024] [Accepted: 07/25/2024] [Indexed: 09/03/2024] Open
Abstract
Ovine pulmonary adenocarcinoma (OPA) is an infectious, neoplastic lung disease of sheep that causes significant animal welfare and economic issues throughout the world. Understanding OPA pathogenesis is key to developing tools to control its impact. Central to this need is the availability of model systems that can monitor and track events after Jaagsiekte sheep retrovirus (JSRV) infection. Here, we report the development of an experimentally induced OPA model intended for this purpose. Using three different viral dose groups (low, intermediate and high), localised OPA tumour development was induced by bronchoscopic JSRV instillation into the segmental bronchus of the right cardiac lung lobe. Pre-clinical OPA diagnosis and tumour progression were monitored by monthly computed tomography (CT) imaging and trans-thoracic ultrasound scanning. Post mortem examination and immunohistochemistry confirmed OPA development in 89% of the JSRV-instilled animals. All three viral doses produced a range of OPA lesion types, including microscopic disease and gross tumours; however, larger lesions were more frequently identified in the low and intermediate viral groups. Overall, 31% of JSRV-infected sheep developed localised advanced lesions. Of the sheep that developed localised advanced lesions, tumour volume doubling times (calculated using thoracic CT 3D reconstructions) were 14.8 ± 2.1 days. The ability of ultrasound to track tumour development was compared against CT; the results indicated a strong significant association between paired CT and ultrasound measurements at each time point (R2 = 0.799, p < 0.0001). We believe that the range of OPA lesion types induced by this model replicates aspects of naturally occurring disease and will improve OPA research by providing novel insights into JSRV infectivity and OPA disease progression.
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Affiliation(s)
- Chris Cousens
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - James Meehan
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - David Collie
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Steven Wright
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Ziyuan Chang
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Helen Todd
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - Jo Moore
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - Lynn Grant
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Carola R. Daniel
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Peter Tennant
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Adrian Ritchie
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - James Nixon
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Chris Proudfoot
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Stefano Guido
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Helen Brown
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Calum D. Gray
- Edinburgh Imaging Facility, Queen’s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK;
| | - Tom J. MacGillivray
- Centre for Clinical Brain Sciences, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, EH16 4SB, UK;
| | - R. Eddie Clutton
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Stephen N. Greenhalgh
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - Rachael Gregson
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
| | - David J. Griffiths
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, UK; (C.C.); (H.T.); (J.M.); (D.J.G.)
| | - James Spivey
- Interventional Oncology, Johnson & Johnson Enterprise Innovation, Inc., One Johnson & Johnson Plaza, New Brunswick, NJ 08933, USA; (J.S.); (N.S.); (C.E.E.)
| | - Nicole Storer
- Interventional Oncology, Johnson & Johnson Enterprise Innovation, Inc., One Johnson & Johnson Plaza, New Brunswick, NJ 08933, USA; (J.S.); (N.S.); (C.E.E.)
| | - Chad E. Eckert
- Interventional Oncology, Johnson & Johnson Enterprise Innovation, Inc., One Johnson & Johnson Plaza, New Brunswick, NJ 08933, USA; (J.S.); (N.S.); (C.E.E.)
| | - Mark Gray
- The Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Easter Bush, Roslin, Edinburgh EH25 9RG, UK; (J.M.); (D.C.); (S.W.); (Z.C.); (L.G.); (C.R.D.); (P.T.); (A.R.); (J.N.); (C.P.); (S.G.); (H.B.); (R.E.C.); (S.N.G.); (R.G.)
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Intranasal application of adeno-associated viruses: a systematic review. Transl Res 2022; 248:87-110. [PMID: 35597541 DOI: 10.1016/j.trsl.2022.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 04/12/2022] [Accepted: 05/16/2022] [Indexed: 01/13/2023]
Abstract
Adeno-associated viruses (AAVs) represent some of the most commonly employed vectors for targeted gene delivery and their extensive study has resulted in the approval of multiple gene therapies to treat human diseases. The intranasal route of vector application in gene therapy offers several advantages over traditional ways of administration. In addition to targeting local tissue like the olfactory epithelium, it provides minimally invasive access to various organ systems, including the central nervous system and the respiratory tract. Through a systematic literature review, a total of 53 articles that investigated the intranasal application of AAVs were identified, included, and summarized in this manuscript. Within these studies, AAV-based gene therapy was mainly investigated for its application in various infectious, pulmonary, or neurologic and/or psychiatric diseases. This review gives a comprehensive overview of the current technological state of the art regarding the intranasal application of AAVs for gene transfer and discusses remaining hurdles, which still have to be resolved before this approach can effectively be implemented in the routine clinical setting.
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Mahmoud NA, Elshafei AM, Almofti YA. A novel strategy for developing vaccine candidate against Jaagsiekte sheep retrovirus from the envelope and gag proteins: an in-silico approach. BMC Vet Res 2022; 18:343. [PMID: 36085036 PMCID: PMC9463060 DOI: 10.1186/s12917-022-03431-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/29/2022] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Sheep pulmonary adenocarcinoma (OPA) is a contagious lung cancer of sheep caused by the Jaagsiekte retrovirus (JSRV). OPA typically has a serious economic impact worldwide. A vaccine has yet to be developed, even though the disease has been globally spread, along with its complications. This study aimed to construct an effective multi-epitopes vaccine against JSRV eliciting B and T lymphocytes using immunoinformatics tools. RESULTS The designed vaccine was composed of 499 amino acids. Before the vaccine was computationally validated, all critical parameters were taken into consideration; including antigenicity, allergenicity, toxicity, and stability. The physiochemical properties of the vaccine displayed an isoelectric point of 9.88. According to the Instability Index (II), the vaccine was stable at 28.28. The vaccine scored 56.51 on the aliphatic index and -0.731 on the GRAVY, indicating that the vaccine was hydrophilic. The RaptorX server was used to predict the vaccine's tertiary structure, the GalaxyWEB server refined the structure, and the Ramachandran plot and the ProSA-web server validated the vaccine's tertiary structure. Protein-sol and the SOLPro servers showed the solubility of the vaccine. Moreover, the high mobile regions in the vaccine's structure were reduced and the vaccine's stability was improved by disulfide engineering. Also, the vaccine construct was docked with an ovine MHC-1 allele and showed efficient binding energy. Immune simulation remarkably showed high levels of immunoglobulins, T lymphocytes, and INF-γ secretions. The molecular dynamic simulation provided the stability of the constructed vaccine. Finally, the vaccine was back-transcribed into a DNA sequence and cloned into a pET-30a ( +) vector to affirm the potency of translation and microbial expression. CONCLUSION A novel multi-epitopes vaccine construct against JSRV, was formed from B and T lymphocytes epitopes, and was produced with potential protection. This study might help in controlling and eradicating OPA.
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Affiliation(s)
- Nuha Amin Mahmoud
- Department of Biochemistry, Genetics and Molecular Biology/ Faculty of Medicine and Surgery, National University, Khartoum, Sudan
| | - Abdelmajeed M Elshafei
- Department of Biochemistry, Genetics and Molecular Biology/ Faculty of Medicine and Surgery, National University, Khartoum, Sudan
| | - Yassir A Almofti
- Department of Biochemistry, Genetics and Molecular Biology/ Faculty of Medicine and Surgery, National University, Khartoum, Sudan.
- Department of Molecular Biology and Bioinformatics, College of Veterinary Medicine, University of Bahri, Khartoum, Sudan.
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Shadmehri M, Ashrafi-Helan J, Firouzamandi M. Mutation and up-regulation of TP53 in ovine pulmonary adenocarcinoma lung cells as a model of human lung cancer. VETERINARY RESEARCH FORUM : AN INTERNATIONAL QUARTERLY JOURNAL 2022; 13:349-356. [PMID: 36320308 PMCID: PMC9548218 DOI: 10.30466/vrf.2021.128764.2976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 03/01/2021] [Indexed: 12/02/2022]
Abstract
Ovine pulmonary adenocarcinoma (OPA) is a model of human lung cancer and fatal viral disease that causes neoplasia in sheep respiratory cells. In the current study, 986 lung samples was inspected in the slaughterhouse, and finally twenty OPA lung organs were clinically diagnosed and five healthy lung organs were assigned as the control sample. Three SSCP patterns were detected for the affected lungs animals in comparison with the healthy lungs. In addition, sequencing results indicated three different single point mutations in exon 4 of TP53 within infected lungs, whereas no mutations were observed in exon 9 of this gene. Real-time PCR results showed up-regulation of the TP53 gene in all the infected lung cells compared to healthy cells. There was significant correlation between the mutations in exon 4 and OPAand can be used as a useful tool in determining the mechanism of lung cancer.
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Affiliation(s)
| | | | - Masoumeh Firouzamandi
- Correspondence Masoumeh Firouzamandi. PhD, Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran. E-mail:
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Cousens C, Ewing DA, McKendrick IJ, Todd H, Dagleish MP, Scott PR. Efficacy of high-throughput transthoracic ultrasonographic screening for on-farm detection of ovine pulmonary adenocarcinoma. Vet Rec 2022; 191:e1797. [PMID: 35788936 DOI: 10.1002/vetr.1797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/28/2022] [Accepted: 05/11/2022] [Indexed: 11/05/2022]
Abstract
BACKGROUND The aim of this study was to evaluate the efficacy of high-throughput on-farm transthoracic ultrasound (TUS) to screen for ovine pulmonary adenocarcinoma (OPA), an infectious ovine disease of increasing concern. No other routine diagnosis of preclinical OPA is available, or any vaccine or treatment. METHODS More than 80,000 rapid TUS scans were applied on farms with a history of OPA. The TUS results from a convenience sample of 171 TUS-negative and 269 TUS-positive sheep were compared with postmortem histology/immunohistochemistry results, the 'gold standard' reference test for OPA diagnosis. These results, together with new data on within-flock prevalence, allowed estimation of the efficacy of rapid TUS screening to identify OPA (defined as tumours of larger than 1 cm) on-farm. RESULTS The TUS screening had an estimated specificity of 0.998 (95% confidence interval [CI]: 0.998-0.999) and an estimated sensitivity of between 0.76 (95% CI: 0.72-0.79) and 0.99 (95% CI: 0.97-0.99) depending on the presumed false-negative rate applied to the calculation. CONCLUSION High-throughput TUS should be considered for screening to identify individual sheep with OPA and has potential application to indicate flocks at low risk of OPA. However, lower efficacy is likely if conducted by less experienced persons.
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Affiliation(s)
- Chris Cousens
- Moredun Research Institute, Bush Loan, Penicuik, Edinburgh, UK
| | - David A Ewing
- Biomathematics and Statistics Scotland, The King's Buildings, Edinburgh, UK
| | - Iain J McKendrick
- Biomathematics and Statistics Scotland, The King's Buildings, Edinburgh, UK
| | - Helen Todd
- Moredun Research Institute, Bush Loan, Penicuik, Edinburgh, UK
| | - Mark P Dagleish
- Moredun Research Institute, Bush Loan, Penicuik, Edinburgh, UK
| | - Philip R Scott
- Capital Veterinary Services, West Latchfields, Haddington, UK
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Research Progress on Emerging Viral Pathogens of Small Ruminants in China during the Last Decade. Viruses 2022; 14:v14061288. [PMID: 35746759 PMCID: PMC9228844 DOI: 10.3390/v14061288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/09/2022] [Accepted: 06/11/2022] [Indexed: 11/26/2022] Open
Abstract
China is the country with the largest number of domestic small ruminants in the world. Recently, the intensive and large-scale sheep/goat raising industry has developed rapidly, especially in nonpastoral regions. Frequent trading, allocation, and transportation result in the introduction and prevalence of new pathogens. Several new viral pathogens (peste des petits ruminants virus, caprine parainfluenza virus type 3, border disease virus, enzootic nasal tumor virus, caprine herpesvirus 1, enterovirus) have been circulating and identified in China, which has attracted extensive attention from both farmers and researchers. During the last decade, studies examining the etiology, epidemiology, pathogenesis, diagnostic methods, and vaccines for these emerging viruses have been conducted. In this review, we focus on the latest findings and research progress related to these newly identified viral pathogens in China, discuss the current situation and problems, and propose research directions and prevention strategies for different diseases in the future. Our aim is to provide comprehensive and valuable information for the prevention and control of these emerging viruses and highlight the importance of surveillance of emerging or re-emerging viruses.
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Davies P, Strugnell B, Waine K, Wessels M, Cousens C, Willison I. To scan or not to scan? Efficacy of transthoracic ultrasonography for ovine pulmonary adenocarcinoma screening in a large commercial UK sheep flock. Vet Rec 2022; 191:e1578. [PMID: 35347736 DOI: 10.1002/vetr.1578] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/30/2021] [Accepted: 02/18/2022] [Indexed: 01/24/2023]
Abstract
BACKGROUND Transthoracic ultrasonography (TTUS) is currently the only widely used method to diagnose preclinical or subclinical ovine pulmonary adenocarcinoma (OPA) in the live sheep. However, little is known about the test characteristics of TTUS. METHODS One thousand and seventy-four breeding ewes in a flock with evidence of low OPA prevalence underwent TTUS by an experienced operator. Fifty-one sheep were diagnosed with OPA and underwent gross postmortem examination (PME). RESULTS Lesions consistent with OPA were found in only 24% (12/51) of the culled ewes. Thirty-five percent (18/51) of culled ewes had gross lesions consistent with other pulmonary disease and 41% (21/51) had no detectable gross lesions on PME. Histopathology and immunohistochemistry confirmed OPA in only the 12 animals identified with OPA lesions from PME. CONCLUSION Great caution should be exercised when deciding if TTUS is an appropriate screening test in groups of sheep where OPA prevalence may be anticipated to be low. TTUS is a subjective test and thus individual operator ability will influence the sensitivity and specificity of TTUS for OPA diagnosis while the underlying prevalence influences the eventual positive predictive value.
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Affiliation(s)
- Peers Davies
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK
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Mulcrone PL, Zhang J, Pride PM, Lam AK, Frabutt DA, Ball-Kell SM, Xiao W. Genomic Designs of rAAVs Contribute to Pathological Changes in the Livers and Spleens of Mice. ADVANCES IN CELL AND GENE THERAPY 2022; 2022:6807904. [PMID: 36507314 PMCID: PMC9730939 DOI: 10.1155/2022/6807904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Recombinant AAV (rAAV) gene therapy is being investigated as an effective therapy for several diseases including hemophilia B. Reports of liver tumor development in certain mouse models due to AAV treatment and genomic integration of the rAAV vector has raised concerns about the long-term safety and efficacy of this gene therapy. To investigate whether rAAV treatment causes cancer, we utilized two mouse models, inbred C57BL/6 and hemophilia B Balb/C mice (HemB), to test if injecting a high dose of various rAAV8 vectors containing or lacking hFIX transgene, a Poly-A sequence, or the CB or TTR promoter triggered liver fibrosis and/or cancer development over the course of the 6.5-month study. We observed no liver tumors in either mouse cohort regardless of rAAV treatment through ultrasound imaging, gross anatomical assessment at sacrifice, and histology. We did, however, detect differences in collagen deposition in C57BL/6 livers and HemB spleens of rAAV-injected mice. Pathology reports of the HemB mice revealed many pathological phenomena, including fibrosis and inflammation in the livers and spleens across different AAV-injected HemB mice. Mice from both cohorts injected with the TTR-hFIX vector demonstrated minimal adverse events. While not tumorigenic, high dose of rAAVs, especially those with incomplete genomes, can influence liver and spleen health negatively that could be problematic for cementing AAVs as a broad therapeutic option in the clinic.
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Affiliation(s)
- Patrick L. Mulcrone
- Herman B Wells Center for Pediatric Research, Indiana University, USA
- Department of Pediatrics, Indiana University, USA
| | - Junping Zhang
- Herman B Wells Center for Pediatric Research, Indiana University, USA
- Department of Pediatrics, Indiana University, USA
| | - P. Melanie Pride
- Herman B Wells Center for Pediatric Research, Indiana University, USA
| | - Anh K. Lam
- Herman B Wells Center for Pediatric Research, Indiana University, USA
- Department of Pediatrics, Indiana University, USA
| | - Dylan A. Frabutt
- Herman B Wells Center for Pediatric Research, Indiana University, USA
- Department of Microbiology & Immunology, Indiana University, Indianapolis, IN, USA
| | | | - Weidong Xiao
- Herman B Wells Center for Pediatric Research, Indiana University, USA
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Domm JM, Wootton SK, Medin JA, West ML. Gene therapy for Fabry disease: Progress, challenges, and outlooks on gene-editing. Mol Genet Metab 2021; 134:117-131. [PMID: 34340879 DOI: 10.1016/j.ymgme.2021.07.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 07/14/2021] [Accepted: 07/15/2021] [Indexed: 12/14/2022]
Abstract
Gene therapy is the delivery of a therapeutic gene for endogenous cellular expression with the goal of rescuing a disease phenotype. It has been used to treat an increasing number of human diseases with many strategies proving safe and efficacious in clinical trials. Gene delivery may be viral or non-viral, performed in vivo or ex vivo, and relies on gene integration or transient expression; all of these techniques have been applied to the treatment of Fabry disease. Fabry disease is a genetic disorder of the α-galactosidase A gene, GLA, that causes an accumulation of glycosphingolipids in cells leading to cardiac, renal and cerebrovascular damage and eventually death. Currently, there are no curative treatments available, and the therapies that are used have significant drawbacks. These treatment concerns have led to the advent of gene therapies for Fabry disease. The first Fabry patients to receive gene therapy were treated with recombinant lentivirus targeting their hematopoietic stem/progenitor cells. Adeno-associated virus treatments have also begun. Alternatively, the field of gene-editing is a new and rapidly growing field. Gene-editing has been used to repair disease-causing mutations or insert genes into cellular DNA. These techniques have the potential to be applied to the treatment of Fabry disease provided the concerns of gene-editing technology, such as safety and efficiency, were addressed. This review focuses on the current state of gene therapy as it is being developed for Fabry disease, including progresses and challenges as well as an overview of gene-editing and how it may be applied to correct Fabry disease-causing mutations in the future.
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Affiliation(s)
- Jakob M Domm
- Faculty of Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| | - Sarah K Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada
| | - Jeffrey A Medin
- Department of Pediatrics and Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Michael L West
- Department of Medicine, Dalhousie University, Halifax, NS B3H 4R2, Canada.
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Borobia M, De Las Heras M, Godino J, Ferrer LM, Lacasta D, Loste A, Ramos JJ, Ortín A. Jaagsiekte sheep retrovirus found in milk macrophages but not in milk lymphocytes or mammary gland epithelia of naturally infected sheep. J Vet Diagn Invest 2021; 34:112-115. [PMID: 34404281 DOI: 10.1177/10406387211039196] [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] [Indexed: 11/16/2022] Open
Abstract
Jaagsiekte sheep retrovirus (JSRV) causes ovine pulmonary adenocarcinoma. JSRV can be transmitted via infected colostrum or milk, which contain somatic cells (SCs) harboring JSRV provirus. Nevertheless, the cell types involved in this form of transmission and the involvement of the mammary gland remain unknown. We separated adherent cells (macrophages and monocytes) by plastic adherence, and lymphocytes (CD4+ and CD8+ T cells, and B cells) by flow cytometry, from SCs in milk samples from 12 naturally infected, PCR blood test JSRV-positive, subclinical ewes. These cell populations were tested by PCR to detect JSRV provirus. The ewes were euthanized, and mammary gland samples were analyzed immunohistochemically to detect JSRV surface protein. We did not detect JSRV provirus in any milk lymphocyte population, but milk adherent cells were positive in 3 of 12 sheep, suggesting a potential major role of this population in the lactogenic transmission of JSRV. Immunohistochemistry did not reveal positive results in mammary epithelial cells, pointing to a lack of participation of the mammary gland in the biological cycle of JSRV and reducing the probability of excretion of free viral particles in colostrum or milk.
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Affiliation(s)
- Marta Borobia
- Departamento de Patología Animal, Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, Zaragoza, Spain
| | - Marcelo De Las Heras
- Departamento de Patología Animal, Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, Zaragoza, Spain
| | - Javier Godino
- Servicio de Separación Celular y Citometría, Instituto Aragonés de Ciencias de la Salud (IACS), Zaragoza, Spain
| | - Luis M Ferrer
- Departamento de Patología Animal, Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, Zaragoza, Spain
| | - Delia Lacasta
- Departamento de Patología Animal, Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, Zaragoza, Spain
| | - Araceli Loste
- Departamento de Patología Animal, Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, Zaragoza, Spain
| | - Juan J Ramos
- Departamento de Patología Animal, Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, Zaragoza, Spain
| | - Aurora Ortín
- Departamento de Patología Animal, Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, Zaragoza, Spain
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11
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Neoplasia-Associated Wasting Diseases with Economic Relevance in the Sheep Industry. Animals (Basel) 2021; 11:ani11020381. [PMID: 33546178 PMCID: PMC7913119 DOI: 10.3390/ani11020381] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/25/2021] [Accepted: 01/27/2021] [Indexed: 11/16/2022] Open
Abstract
We review three neoplastic wasting diseases affecting sheep generally recorded under common production cycles and with epidemiological and economic relevance in sheep-rearing countries: small intestinal adenocarcinoma (SIA), ovine pulmonary adenocarcinoma (OPA) and enzootic nasal adenocarcinoma (ENA). SIA is prevalent in Australia and New Zealand but present elsewhere in the world. This neoplasia is a tubular or signet-ring adenocarcinoma mainly located in the middle or distal term of the small intestine. Predisposing factors and aetiology are not known, but genetic factors or environmental carcinogens may be involved. OPA is a contagious lung cancer caused by jaagsiekte sheep retrovirus (JSRV) and has been reported in most sheep-rearing countries, resulting in significant economic losses. The disease is clinically characterized by a chronic respiratory process as a consequence of the development of lung adenocarcinoma. Diagnosis is based on the detection of JSRV in the tumour lesion by immunohistochemistry and PCR. In vivo diagnosis may be difficult, mainly in preclinical cases. ENA is a neoplasia of glands of the nasal mucosa and is associated with enzootic nasal tumour virus 1 (ENTV-1), which is similar to JSRV. ENA enzootically occurs in many countries of the world with the exception of Australia and New Zealand. The pathology associated with this neoplasia corresponds with a space occupying lesion histologically characterized as a low-grade adenocarcinoma. The combination of PCR and immunohistochemistry for diagnosis is advised.
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12
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De Las Heras M, Reséndiz RA, González-Sáinz JM, Ortín A. Exogenous Small Ruminant Betaretrovirus Envelope Protein Is Detected in Draining Lymph Nodes in Contagious Respiratory Tumors of Sheep and Goats. Vet Pathol 2020; 58:361-368. [PMID: 33357120 DOI: 10.1177/0300985820980711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Contagious respiratory tumors of sheep and goats are epithelial neoplasms of the lung and nasal cavities. They are associated with oncogenic betaretroviruses known as jaagsiekte sheep retrovirus and enzootic nasal tumor retrovirus of sheep and goats. We investigated the presence of the envelope protein (ENV) of these retroviruses in retropharyngeal and mediastinal lymph nodes using a specific monoclonal antibody by immunohistochemistry methods, single-labeled or combined with ovine B or T lymphocytes or macrophage cell markers. Samples of lymph nodes, fixed in formalin and zinc fixative, were obtained from paraffin-embedded material. Four groups of samples were used: 24 natural cases of ovine pulmonary adenocarcinoma (OPA), 13 of enzootic nasal adenocarcinoma of sheep (ENAS), 19 of enzootic nasal adenocarcinoma of goats (ENAG), and 14 control samples. ENV was detected by single labeling in cortical lymphoid follicles. Six of 24 OPA samples were positive and only in those from sheep with extensive neoplasia. Immunolabeling was detected in 5/13 ENAS and 10/19 ENAG samples. Positive labeling was found either in the intercellular spaces, membranes, or cytoplasm of cells in follicles. Control samples were not correspondingly labeled. Double immunohistochemistry demonstrated co-labeling of ENV and CD21 (B cells and follicular dendritic cells) in all samples, CD14 (macrophage) in OPA samples, and Pax-5 (B cells) in ENAG samples, but not with CD8 or CD4 (T lymphocytes). These results demonstrate the presence of betaretrovirus ENV proteins in nontumor cells in regional lymph nodes in sheep and goats with contagious respiratory tumors.
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13
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Maeda N, Inoshima Y, De Las Heras M, Maenaka K. Enzootic nasal tumor virus type 2 envelope of goats acts as a retroviral oncogene in cell transformation. Virus Genes 2020; 57:50-59. [PMID: 33151445 DOI: 10.1007/s11262-020-01808-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/30/2020] [Indexed: 11/26/2022]
Abstract
Enzootic nasal tumor virus type 1 (ENTV-1) (ovine nasal tumor virus) and ENTV-2 (caprine nasal tumor virus) are known to be causative agents of enzootic nasal adenocarcinoma (ENA) in sheep and goats, respectively. Although the nucleotide and amino acid sequences of ENTV-1 and ENTV-2 are quite similar, they are recognized as phylogenetically distinct viruses. The envelope protein of ENTV-1 functions as an oncoprotein in the in vitro transformation of epithelial cells and fibroblasts. Thus, it is the primary determinant of in vivo tumorigenesis in ENA. As per our knowledge, no previous studies have reported in detail the role of ENTV-2 in ENA tumorigenesis. Here, in order to investigate the molecular mechanism of caprine ENA oncogenesis by ENTV-2, we have attempted to identify the transforming potential of ENTV-2 envelope, and investigated the activation of cell signaling pathways in oncogenic transformation. Our findings confirmed that ENTV-2 envelope was capable of inducing oncogenic transformation of rat cell lines in vitro. Further, we found that MAPK, Akt, and p38 were constitutively activated in ENTV-2 envelope-transformed clone cells. In addition, inhibitor experiments revealed that MEK-MAPK and PI3K-Akt signaling pathways are involved in the ENTV-2 envelope-induced cell transformation. These data indicate that ENTV-2 envelope could induce oncogenic transformation by signaling pathways that are also utilized by ENTV-1 envelope.
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Affiliation(s)
- Naoyoshi Maeda
- Center for Research and Education on Drug Discovery, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo, 060-0812, Japan.
| | - Yasuo Inoshima
- Laboratory of Food and Environmental Hygiene, Cooperative Department of Veterinary Medicine, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Japan
| | | | - Katsumi Maenaka
- Center for Research and Education on Drug Discovery, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo, 060-0812, Japan
- Laboratory of Biomolecular Science, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo, 060-0812, Japan
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14
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Toma C, Bâlteanu VA, Tripon S, Trifa A, Rema A, Amorim I, Pop RM, Popa R, Catoi C, Taulescu M. Exogenous Jaagsiekte Sheep Retrovirus type 2 (exJSRV2) related to ovine pulmonary adenocarcinoma (OPA) in Romania: prevalence, anatomical forms, pathological description, immunophenotyping and virus identification. BMC Vet Res 2020; 16:296. [PMID: 32807166 PMCID: PMC7433209 DOI: 10.1186/s12917-020-02521-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 08/12/2020] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Ovine pulmonary adenocarcinoma (OPA) is a neoplastic disease caused by exogenous Jaagsiekte Sheep Retrovirus (exJSRV). The prevalence of JSRV-related OPA in Eastern European countries, including Romania is unknown. We aimed to investigate: the prevalence and morphological features of OPA (classical and atypical forms) in the Transylvania region (Romania), the immunophenotype of the pulmonary tumors and their relationships with exJSRV infection. A total of 2693 adult ewes slaughtered between 2017 and 2019 in two private slaughterhouses from Transylvania region (Romania) was evaluated. Lung tumors were subsequently assessed by cytology, histology, immunocytochemistry, immunohistochemistry, electron microscopy and DNA testing. RESULTS Out of 2693 examined sheep, 34 had OPA (1.26% prevalence). The diaphragmatic lobes were the most affected. Grossly, the classical OPA was identified in 88.24% of investigated cases and the atypical OPA in 11.76% that included solitary myxomatous nodules. Histopathology results confirmed the presence of OPA in all suspected cases, which were classified into acinar and papillary types. Myxoid growths (MGs) were diagnosed in 6 classical OPA cases and in 2 cases of atypical form. Lung adenocarcinoma was positive for MCK and TTF-1, and MGs showed immunoreaction for Vimentin, Desmin and SMA; Ki67 expression of classical OPA was higher than atypical OPA and MGs. JSRV-MA was identified by IHC (94.11%) in both epithelial and mesenchymal cells of OPA. Immunocytochemistry and electron microscopy also confirmed the JSRV within the neoplastic cells. ExJSRV was identified by PCR in 97.05% of analyzed samples. Phylogenetic analysis revealed the presence of the exJSRV type 2 (MT809678.1) in Romanian sheep affected by lung cancer and showed a high similarity with the UK strain (AF105220.1). CONCLUSIONS In this study, we confirmed for the first time in Romania the presence of exJSRV in naturally occurring OPA in sheep. Additionally, we described the first report of atypical OPA in Romania, and to the best of our knowledge, in Eastern Europe. Finally, we showed that MGs have a myofibroblastic origin.
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Affiliation(s)
- Corina Toma
- Department of Veterinary Pathology, University of Agricultural Sciences and Veterinary Medicine, 3-5 Calea Manastur, 400372, Cluj-Napoca, Romania
| | - Valentin Adrian Bâlteanu
- Laboratory of Genomics, Biodiversity, Animal Breeding and Molecular Pathology, Institute of Life Sciences, University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania
| | - Septiumiu Tripon
- National Institute for Research and Development of Isotopic and Molecular Technology, "C. Crăciun" Electron Microscopy Laboratory, Babeș-Bolyai University, Cluj-Napoca, Romania
| | - Adrian Trifa
- Department of Genetics, "Iuliu Haţieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
- Department of Genetics, "Ion Chiricuta" Cancer Institute, Cluj-Napoca, Romania
| | - Alexandra Rema
- Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua Jorge Viterbo Ferreira nr.228, 4050-313, Porto, Portugal
| | - Irina Amorim
- Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua Jorge Viterbo Ferreira nr.228, 4050-313, Porto, Portugal
| | - Raluca Maria Pop
- Department of Pharmacology, Toxicology and Clinical Pharmacology, Iuliu Haţieganu University of Medicine and Pharmacy Cluj-Napoca, 400337, Cluj-Napoca, Romania
| | - Roxana Popa
- Department of Veterinary Pathology, University of Agricultural Sciences and Veterinary Medicine, 3-5 Calea Manastur, 400372, Cluj-Napoca, Romania
| | - Cornel Catoi
- Department of Veterinary Pathology, University of Agricultural Sciences and Veterinary Medicine, 3-5 Calea Manastur, 400372, Cluj-Napoca, Romania
| | - Marian Taulescu
- Department of Veterinary Pathology, University of Agricultural Sciences and Veterinary Medicine, 3-5 Calea Manastur, 400372, Cluj-Napoca, Romania.
- Laboratory of Genomics, Biodiversity, Animal Breeding and Molecular Pathology, Institute of Life Sciences, University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania.
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15
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Rosales Gerpe MC, van Lieshout LP, Domm JM, van Vloten JP, Datu J, Ingrao JC, Yu DL, de Jong J, Moraes TJ, Krell PJ, Bridle BW, Wootton SK. Optimized Pre-Clinical Grade Production of Two Novel Lentiviral Vector Pseudotypes for Lung Gene Delivery. Hum Gene Ther 2020; 31:459-471. [PMID: 32000531 DOI: 10.1089/hum.2019.211] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Lung gene therapy requires efficient transduction of slow-replicating epithelia and stable expression of delivered transgenes in the respiratory tract. Lentiviral (LV) vectors have the ideal coding, expression, and transducing capacity required for gene therapy. A modified envelope glycoprotein from the Jaagsiekte Sheep Retrovirus, termed Jenv, is well suited for LV-mediated lung gene therapy due to its inherent lung tropism. Here, two novel Jenv-pseudotyped LVs that effectively transduce lung tissue and yield titers similar to the gold standard, vesicular stomatitis virus glycoprotein (VSVg)-pseudotyped LVs, were generated. As the concentration efficiency of LVs was found to depend on envelope pseudotype, a large-scale production method tailored for Jenv-pseudotyped LVs was developed and the most appropriate method of concentration was determined. In contrast to VSVg and Ebola virus glycoprotein-pseudotyped LVs, ultracentrifugation through a sucrose cushion drastically reduced the yield of Jenv LVs, whereas polyethylene glycol precipitation and tangential flow filtration (TFF) proved to be more suitable methods for concentrating Jenv LVs. Importantly, pressure during TFF was found to be crucial for increasing LV recovery. Finally, a unique mouse model was developed to test the suitability of these novel Jenv-pseudotyped LVs for use in lung gene therapy applications.
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Affiliation(s)
- María C Rosales Gerpe
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Laura P van Lieshout
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Jakob M Domm
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Jacob P van Vloten
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Jodre Datu
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Joelle C Ingrao
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Darrick L Yu
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Jondavid de Jong
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Theo J Moraes
- Division of Respiratory Medicine, Department of Pediatrics, Hospital for Sick Children, Toronto, Canada
| | - Peter J Krell
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada
| | - Byram W Bridle
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - Sarah K Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Canada
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The U3 and Env Proteins of Jaagsiekte Sheep Retrovirus and Enzootic Nasal Tumor Virus Both Contribute to Tissue Tropism. Viruses 2019; 11:v11111061. [PMID: 31739606 PMCID: PMC6893448 DOI: 10.3390/v11111061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 11/12/2019] [Accepted: 11/12/2019] [Indexed: 12/11/2022] Open
Abstract
Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV) are small-ruminant betaretroviruses that share high nucleotide and amino acid identity, utilize the same cellular receptor, hyaluronoglucosaminidase 2 (Hyal2) for entry, and transform tissues with their envelope (Env) glycoprotein; yet, they target discrete regions of the respiratory tract—the lung and nose, respectively. This distinct tissue selectivity makes them ideal tools with which to study the pathogenesis of betaretroviruses. To uncover the genetic determinants of tropism, we constructed JSRV–ENTV chimeric viruses and produced lentivectors pseudotyped with the Env proteins from JSRV (Jenv) and ENTV (Eenv). Through the transduction and infection of lung and nasal turbinate tissue slices, we observed that Hyal2 expression levels strongly influence ENTV entry, but that the long terminal repeat (LTR) promoters of these viruses are likely responsible for tissue-specificity. Furthermore, we show evidence of ENTV Env expression in chondrocytes within ENTV-infected nasal turbinate tissue, where Hyal2 is highly expressed. Our work suggests that the unique tissue tropism of JSRV and ENTV stems from the combined effort of the envelope glycoprotein-receptor interactions and the LTR and provides new insight into the pathogenesis of ENTV.
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17
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Transcriptional Response of Ovine Lung to Infection with Jaagsiekte Sheep Retrovirus. J Virol 2019; 93:JVI.00876-19. [PMID: 31434729 PMCID: PMC6803282 DOI: 10.1128/jvi.00876-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/10/2019] [Indexed: 02/06/2023] Open
Abstract
Jaagsiekte sheep retrovirus (JSRV) is the etiologic agent of ovine pulmonary adenocarcinoma (OPA), a neoplastic lung disease of sheep. OPA is an important economic and welfare issue for sheep farmers and a valuable naturally occurring animal model for human lung adenocarcinoma. Here, we used RNA sequencing to study the transcriptional response of ovine lung tissue to infection by JSRV. We identified 1,971 ovine genes differentially expressed in JSRV-infected lung compared to noninfected lung, including many genes with roles in carcinogenesis and immunomodulation. The differential expression of selected genes was confirmed using immunohistochemistry and reverse transcription-quantitative PCR. A key finding was the activation of anterior gradient 2, yes-associated protein 1, and amphiregulin in OPA tumor cells, indicating a role for this oncogenic pathway in OPA. In addition, there was differential expression of genes related to innate immunity, including genes encoding cytokines, chemokines, and complement system proteins. In contrast, there was little evidence for the upregulation of genes involved in T-cell immunity. Many genes related to macrophage function were also differentially expressed, reflecting the increased abundance of these cells in OPA-affected lung tissue. Comparison of the genes differentially regulated in OPA with the transcriptional changes occurring in human lung cancer revealed important similarities and differences between OPA and human lung adenocarcinoma. This study provides valuable new information on the pathogenesis of OPA and strengthens the use of this naturally occurring animal model for human lung adenocarcinoma.IMPORTANCE Ovine pulmonary adenocarcinoma is a chronic respiratory disease of sheep caused by jaagsiekte sheep retrovirus (JSRV). OPA is a significant economic problem for sheep farmers in many countries and is a valuable animal model for some forms of human lung cancer. Here, we examined the changes in host gene expression that occur in the lung in response to JSRV infection. We identified a large number of genes with altered expression in infected lung, including factors with roles in cancer and immune system function. We also compared the data from OPA to previously published data from human lung adenocarcinoma and found a large degree of overlap in the genes that were dysregulated. The results of this study provide exciting new avenues for future studies of OPA and may have comparative relevance for understanding human lung cancer.
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18
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Mansour KA, Al-Husseiny SH, Kshash QH, Jassim A. Clinical-histopathological and molecular study of ovine pulmonary adenocarcinoma in Awassi sheep in Al-Qadisiyah Province, Iraq. Vet World 2019; 12:454-458. [PMID: 31089317 PMCID: PMC6487251 DOI: 10.14202/vetworld.2019.454-458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 02/08/2019] [Indexed: 12/20/2022] Open
Abstract
AIM This study aimed to conduct a clinical-histopathological and molecular evaluation of ovine pulmonary adenocarcinoma (OPA) in Awassi sheep in various regions of Al-Qadisiyah Province, Iraq. MATERIALS AND METHODS A total of 150 sheep were clinically evaluated, and the wheelbarrow test was performed. 100 samples (35 blood, 25 lung tissue, 20 lymph node, and 20 lung fluid samples) were randomly selected from living and slaughtered sheep. All samples were subjected to polymerase chain reaction (PCR). Histopathological examinations were performed for four lung tissue and two lymph node samples. RESULTS A diagnosis of OPA was made based on the results of the clinical examination and the clinical signs shown by the animals, such as dyspnea, polypnea, coughing, mucous nasal discharge, moist rales on auscultation of the affected lungs, and emaciation. Interestingly, the animals tested positive for the wheelbarrow test, with frothy nares accompanied by profuse and clear lung fluid. Histopathological examination showed various lesions such as glandular transformation in the lung tissues and emphysema. Moreover, lymph nodes showed marked follicular atrophy and necrosis-associated lymphocyte infiltration in the affected tissues. PCR revealed that 25% of the samples including eight (22.8%) blood, five (20%) lung tissue, five (25%) lymph node, and seven (35%) lung fluid samples were positive for Jaagsiekte sheep retrovirus; this result was highly significant. CONCLUSION The results of our study indicated that in Iraq, OPA diagnosis should be based on pathological findings and results of advanced procedures such as PCR.
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Affiliation(s)
- Khalefa Ali Mansour
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, University of Al-Qadisiyah, Iraq
| | - Saad Hashim Al-Husseiny
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, University of Al-Qadisiyah, Iraq
| | - Qassim Haleem Kshash
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, University of Al-Qadisiyah, Iraq
| | - Asaad Jassim
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, University of Al-Qadisiyah, Iraq
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19
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Sun X, Du F, Liu S. Modulation of autophagy in exJSRV-env-transfected cells through the Akt/mTOR and MAPK signaling pathway. Biochem Biophys Res Commun 2017; 485:672-678. [PMID: 28235485 DOI: 10.1016/j.bbrc.2017.02.099] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 02/18/2017] [Indexed: 12/17/2022]
Abstract
The envelope (Env) of Jaagsiekte sheep retrovirus (JSRV) is an oncoprotein of ovine pulmonary adenocarcinoma (OPA). Autophagy is involved in different cancers, but how it is carcinogenic in JSRV Env is unclear. Modulation of autophagy in exJSRV-env-NM-transfected cells through the Akt/mTOR and MAPK signaling pathway was studied, and we observed strong positive labeling of p-Akt, p-mTOR, p-MEK1/2, p-ERK1/2, p-p38 and p-JNK in tumor cells and typical type II pneumocytes in naturally infected OPA lung tissues, which was co-aligned with JSRV-Env positive cells as shown by immunohistochemical and microscopic analysis. Akt/mTOR and MAPK pathways were activated in OPA lung and JSRV-Env transfected NIH 3T3 cells. Decreased Beclin1 and LC3 II/I suggested that autophagy was inhibited in OPA lung and JSRV-Env transfected NIH 3T3 cells. Beclin1 and LC3 II/I increased in JSRV-Env transfected NIH3T3 cells treated with mTOR inhibitor (rapamycin), ERK1/2 inhibitor (PD 98059), p38 inhibitor (SB 203580) and JNK inhibitor (SP 600125), suggesting that Akt/mTOR and MAPK pathways were responsible for JSRV-Env decreased autophagy. In conclusion, JSRV Env decreased autophagy in JSRV-Env transfected NIH3T3 cells through Akt/mTOR and MAPK pathways, in particular, JNK and p38 pathways.
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Affiliation(s)
- Xiaolin Sun
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture, Hohhot 010018, China.
| | - Fangyuan Du
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture, Hohhot 010018, China
| | - Shuying Liu
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture, Hohhot 010018, China.
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20
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Walsh SR, de Jong JG, van Vloten JP, Gerpe MCR, Santry LA, Wootton SK. Truncation of the enzootic nasal tumor virus envelope protein cytoplasmic tail increases Env-mediated fusion and infectivity. J Gen Virol 2017; 98:108-120. [PMID: 27902399 DOI: 10.1099/jgv.0.000654] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Enzootic nasal tumor virus (ENTV) and Jaagsiekte sheep retrovirus (JSRV) are highly related ovine betaretroviruses that induce nasal and lung tumours in small ruminants, respectively. While the ENTV and JSRV envelope (Env) glycoproteins mediate virus entry using the same cellular receptor, the glycosylphosphatidylinositol-linked protein hyaluronoglucosaminidase, ENTV Env pseudovirions mediate entry into cells from a much more restricted range of species than do JSRV Env pseudovirions. Unlike JSRV Env, ENTV Env does not induce cell fusion at pH 5.0 or above, but rather requires a much lower pH (4.0-4.5) for fusion to occur. The cytoplasmic tail of retroviral envelope proteins is a key modulator of envelope-mediated fusion and pseudotype efficiency, especially in the context of virions composed of heterologous Gag proteins. Here we report that progressive truncation of the ENTV Env cytoplasmic tail improves transduction efficiency of pseudotyped retroviral vectors and that complete truncation of the ENTV Env cytoplasmic tail increases transduction efficiency to wild-type JSRV Env levels by increasing fusogenicity without affecting sensitivity to inhibition by lysosomotropic agents, subcellular localization or efficiency of inclusion into virions. Truncation of the cytoplasmic domain of ENTV Env resulted in a significant advantage in viral entry into all cell types tested, including foetal ovine lung and nasal cells. Taken together, we demonstrate that the cytoplasmic tail modulates the fusion activity of the ENTV Env protein and that truncation of this region enhances Eenv-mediated entry into target cells.
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Affiliation(s)
- Scott R Walsh
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Jondavid G de Jong
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Jacob P van Vloten
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | | | - Lisa A Santry
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
| | - Sarah K Wootton
- Present address: McMaster Immunology Research Centre, McMaster University, Hamilton, ON, Canada.,Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada
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21
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Miller AD, De las Heras M, Yu J, Zhang F, Liu SL, Vaughan AE, Vaughan TL, Rosadio R, Rocca S, Palmieri G, Goedert JJ, Fujimoto J, Wistuba II. Evidence against a role for jaagsiekte sheep retrovirus in human lung cancer. Retrovirology 2017; 14:3. [PMID: 28107820 PMCID: PMC5248497 DOI: 10.1186/s12977-017-0329-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 12/22/2016] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Jaagsiekte sheep retrovirus (JSRV) causes a contagious lung cancer in sheep and goats that can be transmitted by aerosols produced by infected animals. Virus entry into cells is initiated by binding of the viral envelope (Env) protein to a specific cell-surface receptor, Hyal2. Unlike almost all other retroviruses, the JSRV Env protein is also a potent oncoprotein and is responsible for lung cancer in animals. Of concern, Hyal2 is a functional receptor for JSRV in humans. RESULTS We show here that JSRV is fully capable of infecting human cells, as measured by its reverse transcription and persistence in the DNA of cultured human cells. Several studies have indicated a role for JSRV in human lung cancer while other studies dispute these results. To further investigate the role of JSRV in human lung cancer, we used highly-specific mouse monoclonal antibodies and a rabbit polyclonal antiserum against JSRV Env to test for JSRV expression in human lung cancer. JSRV Env expression was undetectable in lung cancers from 128 human subjects, including 73 cases of bronchioalveolar carcinoma (BAC; currently reclassified as lung invasive adenocarcinoma with a predominant lepidic component), a lung cancer with histology similar to that found in JSRV-infected sheep. The BAC samples included 8 JSRV DNA-positive samples from subjects residing in Sardinia, Italy, where sheep farming is prevalent and JSRV is present. We also tested for neutralizing antibodies in sera from 138 Peruvians living in an area where sheep farming is prevalent and JSRV is present, 24 of whom were directly exposed to sheep, and found none. CONCLUSIONS We conclude that while JSRV can infect human cells, JSRV plays little if any role in human lung cancer.
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Affiliation(s)
- A. Dusty Miller
- Fred Hutchinson Cancer Research Center, Seattle, WA USA
- Department of Pathology, University of Washington, Seattle, WA USA
- 17915 Edmundson Rd, Sisters, OR 97759 USA
| | | | - Jingyou Yu
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH USA
- Department of Molecular Microbiology and Immunology, Bond Life Sciences Canter, University of Missouri, Columbia, MO USA
| | - Fushun Zhang
- Department of Molecular Microbiology and Immunology, Bond Life Sciences Canter, University of Missouri, Columbia, MO USA
| | - Shan-Lu Liu
- Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH USA
- Department of Molecular Microbiology and Immunology, Bond Life Sciences Canter, University of Missouri, Columbia, MO USA
| | - Andrew E. Vaughan
- Fred Hutchinson Cancer Research Center, Seattle, WA USA
- Department of Medicine, University of California San Francisco, San Francisco, CA USA
| | - Thomas L. Vaughan
- Program in Epidemiology, Fred Hutchinson Cancer Research Center, Seattle, WA USA
| | - Raul Rosadio
- Veterinary Faculty, National University of San Marcos, Lima, Peru
| | - Stefano Rocca
- Department of Veterinary Medicine, Sassari University, Sassari, Italy
| | - Giuseppe Palmieri
- Unit of Cancer Genetics, Institute of Biomolecular Chemistry, National Research Council, Sassari, Italy
| | - James J. Goedert
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD USA
| | - Junya Fujimoto
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX USA
| | - Ignacio I. Wistuba
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX USA
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22
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Walsh SR, Gerpe MCR, Wootton SK. Construction of a molecular clone of ovine enzootic nasal tumor virus. Virol J 2016; 13:209. [PMID: 28038674 PMCID: PMC5203713 DOI: 10.1186/s12985-016-0660-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 11/25/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Enzootic nasal tumor virus (ENTV-1) is an ovine betaretrovirus that has been linked to enzootic nasal adenocarcinoma (ENA), a contagious tumor of the ethmoid turbinates of sheep. Transmission experiments performed using virus isolated from cell free nasal tumor homogenates suggest that ENTV-1 is the causative agent of ENA; however, this etiological relationship has not been conclusively proven due to the fact that the virus cannot be propagated in vitro nor is there an infectious molecular clone of the virus. METHODS Here we report construction of a molecular clone of ENTV-1 and demonstrate that transfection of this molecular clone into HEK 293T cells produces mature virus particles. RESULTS Analysis of recombinant virus particles derived from the initial molecular clone revealed a defect in the proteolytic processing of Gag; however, this defect could be corrected by co-expression of the Gag-Pro-Pol polyprotein from the highly related Jaagsiekte sheep retrovirus (JSRV) suggesting that the polyprotein cleavage sites in the ENTV-1 molecular clone were functional. Mutagenesis of the molecular clone to correct amino acid variants identified within the pro gene did not restore proteolytic processing; whereas deletion of one proline residue from a polyproline tract located in variable region 1 (VR1) of the matrix resulted in production of CA protein of the mature (cleaved) size strongly suggesting that normal virion morphogenesis and polyprotein cleavage took place. Finally, electron microscopy revealed the presence of spherical virus particles with an eccentric capsid and an average diameter of about 100 nm. CONCLUSION In summary, we have constructed the first molecular clone of ENTV-1 from which mature virus particles can be produced. Future experiments using virus produced from this molecular clone can now be conducted to fulfill Koch's postulates and demonstrate that ENTV-1 is necessary and sufficient to induce ENA in sheep.
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Affiliation(s)
- Scott R Walsh
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada.,McMaster Immunology Research Centre, McMaster University, Hamilton, Ontario, Canada
| | - María Carla Rosales Gerpe
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Sarah K Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada.
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23
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Borobia M, De Las Heras M, Ramos JJ, Ferrer LM, Lacasta D, De Martino A, Fernández A, Loste A, Marteles D, Ortín A. Jaagsiekte Sheep Retrovirus Can Reach Peyer's Patches and Mesenteric Lymph Nodes of Lambs Nursed by Infected Mothers. Vet Pathol 2016; 53:1172-1179. [PMID: 27154541 DOI: 10.1177/0300985816641993] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ovine pulmonary adenocarcinoma (OPA) is a contagious lung cancer of sheep caused by jaagsiekte sheep retrovirus (JSRV). It is generally accepted that transmission by the respiratory route occurs under natural conditions. However recent studies strongly indicate that JSRV can also be transmitted to lambs perinatally via colostrum and milk (C/M). The aim of this work was to confirm that C/M can transmit JSRV infection to lambs under natural conditions and investigate the initial events associated with this transmission route. We have analyzed the presence of JSRV in C/M samples from 22 naturally infected, asymptomatic ewes throughout a lactation period, and in various tissues collected from a group of 36 of their lambs that were fed naturally. The lambs were euthanized at 12, 24, 48, and 72 hours and at 5 and 10 days after birth. We detected JSRV-provirus by PCR in the somatic C/M cells from 10/22 ewes (45.45%). The virus was also detected in 9/36 lambs (25%). JSRV-infected cells, with lymphoreticular-like morphology, were observed by immunohistochemistry (IHC) and in situ hybridization (ISH) in Peyer's patches (PP) from the small intestine of the youngest lambs and in mesenteric lymph nodes (MLN) from lambs older than 72 hours. The virus was also detected by PCR in white blood cells (WBC) in 2/36 lambs (5.5%). These results confirm colostral transmission of JSRV to lambs under natural conditions. Infected lymphoreticular cells contained in C/M appear to be involved. These cells can cross the intestinal barrier of newborn lambs, reach the MLN and enter into circulation.
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Affiliation(s)
- M Borobia
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - M De Las Heras
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - J J Ramos
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - L M Ferrer
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - D Lacasta
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - A De Martino
- Unidad de Anatomía Patológica, Centro de Investigación Biomédica de Aragón (CIBA), Zaragoza, Spain
| | - A Fernández
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - A Loste
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - D Marteles
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
| | - A Ortín
- Departamento de Patología Animal, Facultad de Veterinaria, Universidad de Zaragoza, Spain
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24
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Fox KA, Wootton S, Marolf A, Rouse N, LeVan I, Spraker T, Miller M, Quackenbush S. Experimental Transmission of Bighorn Sheep Sinus Tumors to Bighorn Sheep (Ovis canadensis canadensis) and Domestic Sheep. Vet Pathol 2016; 53:1164-1171. [PMID: 27020536 DOI: 10.1177/0300985816634810] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Bighorn sheep sinus tumors are a recently described disease affecting the paranasal sinuses of Rocky Mountain bighorn sheep (Ovis canadensis canadensis). Several features of this disease suggest an infectious cause, although a specific etiologic agent has not been identified. To test the hypothesis that bighorn sheep sinus tumors are caused by an infectious agent, we inoculated 4 bighorn sheep lambs and 4 domestic sheep lambs intranasally with a cell-free filtrate derived from a naturally occurring bighorn sheep sinus tumor; we held 1 individual of each species as a control. Within 18 months after inoculation, all 4 inoculated domestic sheep (100%) and 1 of the 4 inoculated bighorn sheep (25%) developed tumors within the ethmoid sinuses or nasal conchae, with features similar to naturally occurring bighorn sheep sinus tumors. Neither of the uninoculated sheep developed tumors. Histologically, the experimentally transmitted tumors were composed of stellate to spindle cells embedded within a myxoid matrix, with marked bone production. Tumor cells stained positively with vimentin, S100, alpha smooth muscle actin, and osteocalcin, suggesting origin from a multipotent mesenchymal cell. A periosteal origin for these tumors is suspected. Immunohistochemical staining for the envelope protein of JSRV (with cross-reactivity to ENTV) was equivocal, and PCR assays specific for these agents were negative.
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Affiliation(s)
- K A Fox
- Colorado Division of Parks and Wildlife, Wildlife Health Program, Fort Collins, CO, USA Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - S Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - A Marolf
- Department of Environmental and Radiological Health Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - N Rouse
- Colorado Division of Parks and Wildlife, Wildlife Health Program, Fort Collins, CO, USA Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - I LeVan
- Colorado Division of Parks and Wildlife, Wildlife Health Program, Fort Collins, CO, USA
| | - T Spraker
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - M Miller
- Colorado Division of Parks and Wildlife, Wildlife Health Program, Fort Collins, CO, USA
| | - S Quackenbush
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
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25
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Cousens C, Alleaume C, Bijsmans E, Martineau HM, Finlayson J, Dagleish MP, Griffiths DJ. Jaagsiekte sheep retrovirus infection of lung slice cultures. Retrovirology 2015; 12:31. [PMID: 25889156 PMCID: PMC4419405 DOI: 10.1186/s12977-015-0157-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 03/14/2015] [Indexed: 11/10/2022] Open
Abstract
Background Jaagsiekte sheep retrovirus (JSRV) is the causative agent of ovine pulmonary adenocarcinoma (OPA), a transmissible neoplastic disease of sheep. OPA is an economically important veterinary disease and is also a valuable naturally occurring animal model of human lung cancer, with which it shares a similar histological appearance and the activation of common cell signaling pathways. Interestingly, the JSRV Env protein is directly oncogenic and capable of driving cellular transformation in vivo and in vitro. Previous studies of JSRV infection in cell culture have been hindered by the lack of a permissive cell line for the virus. Here, we investigated the ability of JSRV to infect slices of ovine lung tissue cultured ex vivo. Results We describe the use of precision cut lung slices from healthy sheep to study JSRV infection and transformation ex vivo. Following optimization of the culture system we characterized JSRV infection of lung slices and compared the phenotype of infected cells to natural field cases and to experimentally-induced OPA tumors from sheep. JSRV was able to infect cells within lung slices, to produce new infectious virions and induce cell proliferation. Immunohistochemical labeling revealed that infected lung slice cells express markers of type II pneumocytes and phosphorylated Akt and ERK1/2. These features closely resemble the phenotype of natural and experimentally-derived OPA in sheep, indicating that lung slice culture provides an authentic ex vivo model of OPA. Conclusions We conclude that we have established an ex vivo model of JSRV infection. This model will be valuable for future studies of JSRV replication and early events in oncogenesis and provides a novel platform for studies of JSRV-induced lung cancer.
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Affiliation(s)
- Chris Cousens
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK.
| | - Charline Alleaume
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK.
| | - Esther Bijsmans
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK.
| | - Henny M Martineau
- Department of Pathology and Infectious Diseases, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire, UK.
| | - Jeanie Finlayson
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK.
| | - Mark P Dagleish
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK.
| | - David J Griffiths
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh, UK.
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26
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Cousens C, Gibson L, Finlayson J, Pritchard I, Dagleish MP. Prevalence of ovine pulmonary adenocarcinoma (Jaagsiekte) in a UK slaughterhouse sheep study. Vet Rec 2015; 176:413. [PMID: 25721510 DOI: 10.1136/vr.102880] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2014] [Indexed: 12/22/2022]
Affiliation(s)
- C Cousens
- Moredun Research Institute, Edinburgh EH26 0PZ, UK
| | - L Gibson
- SAC Consulting Veterinary Services, Allan Watt Building, Bush Estate, Penicuik EH26 0QE, UK
| | - J Finlayson
- Moredun Research Institute, Edinburgh EH26 0PZ, UK
| | - I Pritchard
- SAC Consulting Veterinary Services, Allan Watt Building, Bush Estate, Penicuik EH26 0QE, UK
| | - M P Dagleish
- Moredun Research Institute, Edinburgh EH26 0PZ, UK
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27
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Abstract
A few human tumor types have been modeled in mice using genetic or chemical tools. The final goal of these efforts is to establish models that mimic not only the location and cellular origin of human cancers but also their genetic aberrations and morphologic appearances. The latter has been neglected by most investigators, and comparative histopathology of human versus mouse cancers is not readily available. This issue is exacerbated by the fact that some human malignancies comprise a whole spectrum of cancer subtypes that differ molecularly and morphologically. Lung cancer is a paradigm that appears not only as non-small cell and small-cell lung cancer but comprises a plethora of subtypes with distinct morphologic features. This review discusses species-specific and common morphological features of non-small cell lung cancer in mice and humans. Potential inconsistencies and the need for refined genetic tools are discussed in the context of a comparative analysis between commonly employed RAS-induced mouse tumors and human lung cancers.
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Affiliation(s)
- Helmut H Popper
- Institute of Pathology, Research Unit Molecular Lung & Pleura Pathology, Medical University of Graz, Auenbruggerplatz 25, 8036, Graz, Austria,
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28
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The sheep tetherin paralog oBST2B blocks envelope glycoprotein incorporation into nascent retroviral virions. J Virol 2014; 89:535-44. [PMID: 25339764 DOI: 10.1128/jvi.02751-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
UNLABELLED Bone marrow stromal cell antigen 2 (BST2) is a cellular restriction factor with a broad antiviral activity. In sheep, the BST2 gene is duplicated into two paralogs termed oBST2A and oBST2B. oBST2A impedes viral exit of the Jaagsiekte sheep retroviruses (JSRV), most probably by retaining virions at the cell membrane, similar to the "tethering" mechanism exerted by human BST2. In this study, we provide evidence that unlike oBST2A, oBST2B is limited to the Golgi apparatus and disrupts JSRV envelope (Env) trafficking by sequestering it. In turn, oBST2B leads to a reduction in Env incorporation into viral particles, which ultimately results in the release of virions that are less infectious. Furthermore, the activity of oBST2B does not seem to be restricted to retroviruses, as it also acts on vesicular stomatitis virus glycoproteins. Therefore, we suggest that oBST2B exerts antiviral activity using a mechanism distinct from the classical tethering restriction observed for oBST2A. IMPORTANCE BST2 is a powerful cellular restriction factor against a wide range of enveloped viruses. Sheep possess two paralogs of the BST2 gene called oBST2A and oBST2B. JSRV, the causative agent of a transmissible lung cancer of sheep, is known to be restricted by oBST2A. In this study, we show that unlike oBST2A, oBST2B impairs the normal cellular trafficking of JSRV envelope glycoproteins by sequestering them within the Golgi apparatus. We also show that oBST2B decreases the incorporation of envelope glycoprotein into JSRV viral particles, which in turn reduces virion infectivity. In conclusion, oBST2B exerts a novel antiviral activity that is distinct from those of BST2 proteins of other species.
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29
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Walsh SR, Stinson KJ, Menzies PI, Wootton SK. Development of an ante-mortem diagnostic test for enzootic nasal tumor virus and detection of neutralizing antibodies in host serum. J Gen Virol 2014; 95:1843-1854. [PMID: 24836673 DOI: 10.1099/vir.0.064956-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Enzootic nasal adenocarcinoma (ENA) is a contagious neoplasm of the nasal mucosa of sheep and goats and is associated with enzootic nasal tumour virus (ENTV). As ENA is a common disease in North America and there are no vaccines against ENTV-1, diagnostic tests that can identify infected animals and assist with eradication and disease surveillance efforts are greatly needed. In this study, we endeavoured to develop a novel, non-invasive diagnostic tool that could be used not only to validate clinical signs of ENA but also to detect ENTV-1 infection prior to the onset of disease signs (i.e. pre-clinical diagnosis). Cytology, serology and reverse transcription (RT)-PCR-based diagnostic methods were investigated. Although the cytology-based assay was able to detect ENTV-1 infection in some animals, it had poor sensitivity and specificity and thus was not developed further as an ante-mortem diagnostic method. Three different assays, including ELISA, Western blotting and virus neutralization, were developed to detect the presence of ENTV-1-specific antibodies in sheep serum. Whilst a surprisingly large number of sheep mounted an antibody-mediated immune response against ENTV-1, and in some cases neutralizing, correlation with disease status was poor. In contrast, RT-PCR on RNA extracted from nasal swabs reliably detected exogenous ENTV-1 sequences, did not amplify endogenous ovine betaretroviral sequences, demonstrated high concordance with immunohistochemical staining for ENTV-1 envelope protein, and had perfect sensitivity and specificity. This report describes a practical and highly specific RT-PCR technique for the detection of clinical and pre-clinical ENA that may prove beneficial in future control or eradication programmes.
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Affiliation(s)
- Scott R Walsh
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Kevin J Stinson
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Paula I Menzies
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Sarah K Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
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30
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Linnerth-Petrik NM, Santry LA, Petrik JJ, Wootton SK. Opposing functions of Akt isoforms in lung tumor initiation and progression. PLoS One 2014; 9:e94595. [PMID: 24722238 PMCID: PMC3983215 DOI: 10.1371/journal.pone.0094595] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 03/17/2014] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND The phosphatidylinositol 3-kinase-regulated protein kinase, Akt, plays an important role in the initiation and progression of human cancer. Mammalian cells express three Akt isoforms (Akt1-3), which are encoded by distinct genes. Despite sharing a high degree of amino acid identity, phenotypes observed in knockout mice suggest that Akt isoforms are not functionally redundant. The relative contributions of the different Akt isoforms to oncogenesis, and the effect of their deficiencies on tumor development, are not well understood. METHODS Here we demonstrate that Akt isoforms have non-overlapping and sometimes opposing functions in tumor initiation and progression using a viral oncogene-induced mouse model of lung cancer and Akt isoform-specific knockout mice. RESULTS Akt1 ablation significantly delays initiation of lung tumor growth, whereas Akt2 deficiency dramatically accelerates tumorigenesis in this mouse model. Ablation of Akt3 had a small, not statistically significant, stimulatory effect on tumor induction and growth by the viral oncogene. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling and Ki67 immunostaining of lung tissue sections revealed that the delayed tumor induction in Akt1-/- mice was due to the inhibitory effects of Akt1 ablation on cell growth and survival. Conversely, the accelerated growth rate of lung tumors in Akt2-/- and Akt3-/- mice was due to increased cell proliferation and reduced tumor cell apoptosis. Investigation of Akt signaling in tumors from Akt knockout mice revealed that the lack of Akt1 interrupted the propagation of signaling in tumors to the critical downstream targets, GSK-3α/β and mTOR. CONCLUSIONS These results demonstrate that the degree of functional redundancy between Akt isoforms in the context of lung tumor initiation is minimal. Given that this mouse model exhibits considerable similarities to human lung cancer, these findings have important implications for the design and use of Akt inhibitors for the treatment of lung cancer.
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Affiliation(s)
- Nicolle M Linnerth-Petrik
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Lisa A Santry
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - James J Petrik
- Department of Biomedical Science, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Sarah K Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
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31
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Jaagsiekte sheep retrovirus detected in human lung cancer tissue arrays. BMC Res Notes 2014; 7:160. [PMID: 24642139 PMCID: PMC3995318 DOI: 10.1186/1756-0500-7-160] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 03/13/2014] [Indexed: 01/15/2023] Open
Abstract
Background Adenocarcinoma is the most common type of non-small cell lung cancer and is frequently observed in non-smoking patients. Adenocarcinoma in-situ (formerly referred to as bronchioloalveolar carcinoma) is a subset of lung adenocarcinoma characterized by growth along alveolar septae without evidence of stromal, vascular, or pleural invasion, that disproportionately affects never-smokers, women, and Asians. Adenocarcinoma in-situ is morphologically and histologically similar to a contagious lung neoplasm of sheep called ovine pulmonary adenocarcinoma (OPA). OPA is caused by infection with the exogenous betaretrovirus, jaagsiekte sheep retrovirus (JSRV), whose envelope protein (Env) is a potent oncogene. Several studies have reported that a proportion of human lung adenocarcinomas are immunopositive for an antigen related to the Gag protein of JSRV, however other groups have been unable to verify these observations by PCR. Methods Here we examine human lung cancer tissue arrays (TA) for evidence of JSRV Env protein and DNA by immunohistochemical staining and PCR, respectively. Results Our results reveal that a subset of human lung cancers express an antigen that reacts with a JSRV Env-specific monoclonal antibody in immunohistochemistry and that exogenous JSRV-like env and gag sequences can be amplified from TA tumor samples, albeit inefficiently. Conclusions While a causative role has not been established, these data suggest that a JSRV-like virus might infect humans. With next generation sequencing approaches, a JSRV-like virus in human lung cancers may be identified which could have profound implications for prevention, diagnosis and therapy.
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32
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Solitary Tumours Associated with Jaagsiekte Retrovirus in Sheep are Heterogeneous and Contain Cells Expressing Markers Identifying Progenitor Cells in Lung Repair. J Comp Pathol 2014; 150:138-47. [DOI: 10.1016/j.jcpa.2013.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 07/23/2013] [Accepted: 09/03/2013] [Indexed: 11/21/2022]
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33
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Host species barriers to Jaagsiekte sheep retrovirus replication and carcinogenesis. J Virol 2013; 87:10752-62. [PMID: 23903827 DOI: 10.1128/jvi.01472-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Understanding the factors governing host species barriers to virus transmission has added significantly to our appreciation of virus pathogenesis. Jaagsiekte sheep retrovirus (JSRV) is the causative agent of ovine pulmonary adenocarcinoma (OPA), a transmissible lung cancer of sheep that has rarely been found in goats. In this study, in order to further clarify the pathogenesis of OPA, we investigated whether goats are resistant to JSRV replication and carcinogenesis. We found that JSRV induces lung tumors in goats with macroscopic and histopathological features that dramatically differ from those in sheep. However, the origins of the tumor cells in the two species are identical. Interestingly, in experimentally infected lambs and goat kids, we revealed major differences in the number of virus-infected cells at early stages of infection. These differences were not related to the number of available target cells for virus infection and cell transformation or the presence of a host-specific immune response toward JSRV. Indeed, we also found that goats possess transcriptionally active endogenous retroviruses (enJSRVs) that likely influence the host immune response toward the exogenous JSRV. Overall, these results suggest that goat cells, or at least those cells targeted for viral carcinogenesis, are not permissive to virus replication but can be transformed by JSRV.
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Walsh SR, Linnerth-Petrik NM, Yu DL, Foster RA, Menzies PI, Diaz-Méndez A, Chalmers HJ, Wootton SK. Experimental transmission of enzootic nasal adenocarcinoma in sheep. Vet Res 2013; 44:66. [PMID: 23899161 PMCID: PMC3734154 DOI: 10.1186/1297-9716-44-66] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 07/26/2013] [Indexed: 12/21/2022] Open
Abstract
Enzootic nasal adenocarcinoma (ENA) is a contagious neoplasm of the secretory epithelial cells of the nasal mucosa of sheep and goats. It is associated with the betaretrovirus, enzootic nasal tumor virus (ENTV), but a causative relationship has yet to be demonstrated. In this study, 14-day-old lambs were experimentally infected via nebulization with cell-free tumor filtrates derived from naturally occurring cases of ENA. At 12 weeks post-infection (wpi), one of the five infected lambs developed clinical signs, including continuous nasal discharge and open mouth breathing, and was euthanized. Necropsy revealed the presence of a large bilateral tumor occupying the nasal cavity. At 45 wpi, when the study was terminated, none of the remaining infected sheep showed evidence of tumors either by computed tomography or post-mortem examination. ENTV-1 proviral DNA was detected in the nose, lung, spleen, liver and kidney of the animal with experimentally induced ENA, however there was no evidence of viral protein expression in tissues other than the nose. Density gradient analysis of virus particles purified from the experimentally induced nasal tumor revealed a peak reverse transcriptase (RT) activity at a buoyant density of 1.22 g/mL which was higher than the 1.18 g/mL density of peak RT activity of virus purified from naturally induced ENA. While the 1.22 g/mL fraction contained primarily immature unprocessed virus particles, mature virus particles with a similar morphology to naturally occurring ENA could be identified by electron microscopy. Full-length sequence analysis of the ENTV-1 genome from the experimentally induced tumor revealed very few nucleotide changes relative to the original inoculum with only one conservative amino acid change. Taken together, these results demonstrate that ENTV-1 is associated with transmissible ENA in sheep and that under experimental conditions, lethal tumors are capable of developing in as little as 12 wpi demonstrating the acutely oncogenic nature of this ovine betaretrovirus.
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Pathological and Aetiological Studies in Sheep Exhibiting Extrathoracic Metastasis of Ovine Pulmonary Adenocarcinoma (Jaagsiekte). J Comp Pathol 2013; 148:139-47. [DOI: 10.1016/j.jcpa.2012.06.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 05/25/2012] [Accepted: 06/06/2012] [Indexed: 12/15/2022]
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Linnerth-Petrik NM, Santry LA, Yu DL, Wootton SK. Adeno-associated virus vector mediated expression of an oncogenic retroviral envelope protein induces lung adenocarcinomas in immunocompetent mice. PLoS One 2012; 7:e51400. [PMID: 23251519 PMCID: PMC3519541 DOI: 10.1371/journal.pone.0051400] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 11/02/2012] [Indexed: 12/23/2022] Open
Abstract
Lung cancer is the most common cause of cancer-related death worldwide. A poor overall survival rate of 16% necessitates the need for novel treatment strategies. Mouse models of lung cancer are important tools for analyzing the significance of somatic mutations in the initiation and progression of lung cancer. Of additional importance, however, are animal models of virally induced cancers. JSRV is a simple betaretrovirus that causes contagious lung cancer in sheep known as ovine pulmonary adenocarcinoma and closely resembles human lung adenocarcinoma. Previously we showed that expression of the JSRV envelope (Env) from an AAV vector induced lung tumors in immunodeficient mice, but not in immunocompetent mice. Because of the importance of studying lung cancer in the context of an intact immune system we sought to improve our mouse model. In this report, we employed the use of a strong JSRV enhancer-promoter combination to express Env at high levels and demonstrate for the first time, lung tumor induction in immunocompetent mice. This occurred despite a robust Env-specific antibody-mediated immune response. The PI3K/Akt and MAPK pathways were activated in both immunocompetent and immunodeficient mice, however, differential activation of PTEN, GSKα, p70S6K, p38MAPK, ATF2 and STAT5 was observed. A JSRV Env lung tumor-derived cell line was shown to have a similar signal transduction activation profile as Env-induced lung tumors in C57BL/6 mice. Given the similarities between our model and pulmonary adenocarcinomas in humans, and the ease with which tumors can be induced in any transgenic mouse, this system can be used to uncover novel mechanisms involved lung tumorigenesis.
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Affiliation(s)
| | - Lisa A. Santry
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Darrick L. Yu
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| | - Sarah K. Wootton
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
- * E-mail:
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Vaughan AE, Halbert CL, Wootton SK, Miller AD. Lung cancer in mice induced by the jaagsiekte sheep retrovirus envelope protein is not maintained by rare cancer stem cells, but tumorigenicity does correlate with Wnt pathway activation. Mol Cancer Res 2011; 10:86-95. [PMID: 22064658 DOI: 10.1158/1541-7786.mcr-11-0285] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
JSRV, a simple beta-retrovirus, is the etiologic agent of ovine pulmonary adenocarcinoma, a form of non-small cell lung cancer in sheep and goats. It has been shown that the envelope protein alone is sufficient to induce tumorigenesis in the lungs of mice when delivered via an adeno-associated viral vector. Here, we tested the hypothesis that JSRV envelope-induced tumors are maintained by a small population of tumor-initiating cells, termed cancer stem cells. To test this hypothesis, dissociated cancer cells were sorted from envelope-induced tumors in mouse lung based on the putative stem cell markers Sca-1, CD34, and CD133, the pluripotency-associated transcription factor Oct4, and the level of Wnt signaling. No association with increased tumor-initiating capacity was found with any of the cell-surface markers. In addition, we were unable to detect any evidence of Oct4 expression in tumor-bearing mouse lung. However, tumor cells possessing an active Wnt signaling pathway did show a significant correlation with increased tumor formation upon transplantation. Limiting dilution transplant analysis suggests the existence of a large fraction of cells with the ability to propagate tumor growth, with increasing tumor initiation potential correlating with activated Wnt signaling.
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Affiliation(s)
- Andrew E Vaughan
- Human Biology and Basic Sciences Divisions, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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Magden E, Quackenbush SL, VandeWoude S. FIV associated neoplasms--a mini-review. Vet Immunol Immunopathol 2011; 143:227-34. [PMID: 21722968 DOI: 10.1016/j.vetimm.2011.06.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Retroviral induced neoplasms have been key to understanding oncogenesis and are important etiologic agents associated with cancer formation. Cats infected with feline immunodeficiency virus (FIV), the feline analogue to human immunodeficiency virus (HIV), are reported to be at increased incidence of neoplasia. This review highlights reported risk factors and tumor cell phenotypes associated with neoplasias arising in FIV-infected animals, differences in oncogenic disease in natural versus experimental FIV infections, and similarities between FIV- and HIV-related malignancies. The most common type of FIV-associated neoplasm reported in the literature is lymphoma, specifically of B-cell origin, with experimentally infected cats developing neoplastic lesions at an earlier age than their naturally infected cohorts. The mechanism of FIV-induced lymphoma has not been completely ascertained, though the majority of published studies addressing this issue suggest oncogenesis arises via indirect mechanisms. HIV-infected individuals have increased risk of neoplasia, specifically B cell lymphoma, in comparison with uninfected individuals. Additional similarities between FIV- and HIV-associated neoplasms include the presence of extranodal lymphoma, a synergism with other oncogenic viruses, and an apparent indirect mechanism of induced oncogenesis. This literature supports study of FIV-associated neoplasms to further characterize this lentiviral-neoplasia association for the benefit of both human and animal disease, and to advance our general knowledge of mechanisms for viral-induced oncogenesis.
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Affiliation(s)
- Elizabeth Magden
- Colorado State University, Department of Microbiology, Immunology, and Pathology, 1619 Campus Delivery, Fort Collins, CO 80523, USA
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Oda SS, Youssef SA. Immunohistochemical and histopathological findings of ovine pulmonary adenocarcinoma (Jaagsiekte) in Egyptian sheep. Trop Anim Health Prod 2011; 43:1611-5. [PMID: 21626063 DOI: 10.1007/s11250-011-9878-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2011] [Indexed: 11/29/2022]
Abstract
Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring retrovirus-induced transmissible lung cancer in sheep. Lungs and associated (bronchial and mediastinal) lymph nodes of seven sheep with OPA were examined. Lungs had few multifocal consolidated slightly elevated gray to white masses ranging from 0.5 to 3 cm in diameter. Histopathologically, these masses appeared as well-differentiated acinar adenocarcinoma with little evidence of anaplasia. The acini composed of well-differentiated cuboidal to low columnar epithelium with clear or vacuolated cytoplasm and low mitotic index. No metastases were observed in the bronchial and mediastinal lymph nodes of any animal. The presence of Jaagsiekte sheep retrovirus (JSRV) was demonstrated in the lungs by immunohistochemistry. JSRV protein was detected in all tumor epithelial cells, histologically normal alveolar type II cells, and few bronchiolar epithelial cells, alveolar macrophages, lymphocytes, and plasma cells. This study is the first to confirm the presence of natural OPA in Egypt.
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Affiliation(s)
- Samah Shehata Oda
- Department of Pathology and Parasitology, Faculty of Veterinary Medicine, Alexandria University, Edfina-Rashid-Behera, Egypt.
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40
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Jaagsiekte sheep retrovirus and enzootic nasal tumor virus promoters drive gene expression in all airway epithelial cells of mice but only induce tumors in the alveolar region of the lungs. J Virol 2011; 85:7535-45. [PMID: 21593165 DOI: 10.1128/jvi.00400-11] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Jaagsiekte sheep retrovirus (JSRV) induces tumors in the distal airways of sheep and goats, while the closely related enzootic nasal tumor virus type 1 (ENTV-1) and ENTV-2 induce tumors in the nasal epithelium of sheep and goats, respectively. When expressed using a strong Rous sarcoma virus promoter, the envelope proteins of these viruses induce tumors in the respiratory tract of mice, but only in the distal airway. To examine the role of the retroviral long terminal repeat (LTR) promoters in determining tissue tropism, adeno-associated virus (AAV) vectors expressing alkaline phosphatase under the control of the JSRV, ENTV-1, or ENTV-2 LTRs were generated and administered to mice. The JSRV LTR was active in all airway epithelial cells, while the ENTV LTRs were active in the nasal epithelium and alveolar type II cells but poorly active in tracheal and bronchial epithelial cells. When vectors were administered systemically, the ENTV-1 and -2 LTRs were inactive in major organs examined, whereas the JSRV showed high-level activity in the liver. When a putative transcriptional enhancer from the 3' end of the env gene was inserted upstream of the JSRV and ENTV-1 LTRs in the AAV vectors, a dramatic increase in transgene expression was observed. However, intranasal administration of AAV vectors containing any combination of ENTV or JSRV LTRs and Env proteins induced tumors only in the lower airway. Our results indicate that mice do not provide an adequate model for nasal tumor induction by ENTV despite our ability to express genes in the nasal epithelium.
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Martineau HM, Cousens C, Imlach S, Dagleish MP, Griffiths DJ. Jaagsiekte sheep retrovirus infects multiple cell types in the ovine lung. J Virol 2011; 85:3341-55. [PMID: 21270155 PMCID: PMC3067841 DOI: 10.1128/jvi.02481-10] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 01/20/2011] [Indexed: 01/06/2023] Open
Abstract
Ovine pulmonary adenocarcinoma (OPA) is a transmissible lung cancer of sheep caused by Jaagsiekte sheep retrovirus (JSRV). The details of early events in the pathogenesis of OPA are not fully understood. For example, the identity of the JSRV target cell in the lung has not yet been determined. Mature OPA tumors express surfactant protein-C (SP-C) or Clara cell-specific protein (CCSP), which are specific markers of type II pneumocytes or Clara cells, respectively. However, it is unclear whether these are the cell types initially infected and transformed by JSRV or whether the virus targets stem cells in the lung that subsequently acquire a differentiated phenotype during tumor growth. To examine this question, JSRV-infected lung tissue from experimentally infected lambs was studied at early time points after infection. Single JSRV-infected cells were detectable 10 days postinfection in bronchiolar and alveolar regions. These infected cells were labeled with anti-SP-C or anti-CCSP antibodies, indicating that differentiated epithelial cells are early targets for JSRV infection in the ovine lung. In addition, undifferentiated cells that expressed neither SP-C nor CCSP were also found to express the JSRV Env protein. These results enhance the understanding of OPA pathogenesis and may have comparative relevance to human lung cancer, for which samples representing early stages of tumor growth are difficult to obtain.
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Affiliation(s)
- Henny M. Martineau
- Moredun Research Institute, Pentlands Science Park, Penicuik, Scotland, United Kingdom
| | - Chris Cousens
- Moredun Research Institute, Pentlands Science Park, Penicuik, Scotland, United Kingdom
| | - Stuart Imlach
- Moredun Research Institute, Pentlands Science Park, Penicuik, Scotland, United Kingdom
| | - Mark P. Dagleish
- Moredun Research Institute, Pentlands Science Park, Penicuik, Scotland, United Kingdom
| | - David J. Griffiths
- Moredun Research Institute, Pentlands Science Park, Penicuik, Scotland, United Kingdom
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Murgia C, Caporale M, Ceesay O, Di Francesco G, Ferri N, Varasano V, de las Heras M, Palmarini M. Lung adenocarcinoma originates from retrovirus infection of proliferating type 2 pneumocytes during pulmonary post-natal development or tissue repair. PLoS Pathog 2011; 7:e1002014. [PMID: 21483485 PMCID: PMC3068994 DOI: 10.1371/journal.ppat.1002014] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 02/04/2011] [Indexed: 01/06/2023] Open
Abstract
Jaagsiekte sheep retrovirus (JSRV) is a unique oncogenic virus with distinctive biological properties. JSRV is the only virus causing a naturally occurring lung cancer (ovine pulmonary adenocarcinoma, OPA) and possessing a major structural protein that functions as a dominant oncoprotein. Lung cancer is the major cause of death among cancer patients. OPA can be an extremely useful animal model in order to identify the cells originating lung adenocarcinoma and to study the early events of pulmonary carcinogenesis. In this study, we demonstrated that lung adenocarcinoma in sheep originates from infection and transformation of proliferating type 2 pneumocytes (termed here lung alveolar proliferating cells, LAPCs). We excluded that OPA originates from a bronchioalveolar stem cell, or from mature post-mitotic type 2 pneumocytes or from either proliferating or non-proliferating Clara cells. We show that young animals possess abundant LAPCs and are highly susceptible to JSRV infection and transformation. On the contrary, healthy adult sheep, which are normally resistant to experimental OPA induction, exhibit a relatively low number of LAPCs and are resistant to JSRV infection of the respiratory epithelium. Importantly, induction of lung injury increased dramatically the number of LAPCs in adult sheep and rendered these animals fully susceptible to JSRV infection and transformation. Furthermore, we show that JSRV preferentially infects actively dividing cell in vitro. Overall, our study provides unique insights into pulmonary biology and carcinogenesis and suggests that JSRV and its host have reached an evolutionary equilibrium in which productive infection (and transformation) can occur only in cells that are scarce for most of the lifespan of the sheep. Our data also indicate that, at least in this model, inflammation can predispose to retroviral infection and cancer.
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Affiliation(s)
- Claudio Murgia
- Medical Research Council – University of Glasgow Centre for Virus Research, Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Marco Caporale
- Medical Research Council – University of Glasgow Centre for Virus Research, Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
- Istituto G. Caporale, Teramo, Italy
| | - Ousman Ceesay
- Medical Research Council – University of Glasgow Centre for Virus Research, Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | | | | | - Vincenzo Varasano
- Dipartimento di Scienze Cliniche Veterinarie, Facolta' di Medicina Veterinaria, Universita' di Teramo, Italy
| | | | - Massimo Palmarini
- Medical Research Council – University of Glasgow Centre for Virus Research, Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
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43
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Jaagsiekte sheep retrovirus biology and oncogenesis. Viruses 2010; 2:2618-48. [PMID: 21994634 PMCID: PMC3185594 DOI: 10.3390/v2122618] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 11/22/2010] [Accepted: 11/23/2010] [Indexed: 11/19/2022] Open
Abstract
Jaagsiekte sheep retrovirus (JSRV) is the causative agent of a lung cancer in sheep known as ovine pulmonary adenocarcinoma (OPA). The disease has been identified around the world in several breeds of sheep and goats, and JSRV infection typically has a serious impact on affected flocks. In addition, studies on OPA are an excellent model for human lung carcinogenesis. A unique feature of JSRV is that its envelope (Env) protein functions as an oncogene. The JSRV Env-induced transformation or oncogenesis has been studied in a variety of cell systems and in animal models. Moreover, JSRV studies have provided insights into retroviral genomic RNA export/expression mechanisms. JSRV encodes a trans-acting factor (Rej) within the env gene necessary for the synthesis of Gag protein from unspliced viral RNA. This review summarizes research pertaining to JSRV-induced pathogenesis, Env transformation, and other aspects of JSRV biology.
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44
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Fox KA, Wootton SK, Quackenbush SL, Wolfe LL, Levan IK, Miller MW, Spraker TR. Paranasal sinus masses of Rocky Mountain bighorn sheep (Ovis canadensis canadensis). Vet Pathol 2010; 48:706-12. [PMID: 20926735 DOI: 10.1177/0300985810383873] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This article describes 10 cases of paranasal sinus masses in Rocky Mountain bighorn sheep (Ovis canadensis canadensis). Among 21 bighorns that were examined from 11 herds in Colorado, 10 individuals (48%) from 4 herds (36%) had masses arising from the paranasal sinuses. Affected animals included 9 of 17 females (53%) and 1 of 4 males (25%), ranging in age from approximately 2 years to greater than 10 years. Defining gross features of these masses included unilateral or bilateral diffuse thickening of the respiratory lining of the maxillary and/or frontal sinuses, with abundant seromucinous exudate in the affected sinus cavities. Defining histologic features of these masses included chronic inflammation and proliferation of mesenchymal and epithelial cells of the mucosa and submucosa. Epithelial changes included hyperplasia of mucosal epithelium, hyperplasia of submucosal glands and ducts, and neoplasia (adenocarcinoma). Mesenchymal changes included submucosal myxedema, submucosal fibroplasia/fibrosis, bone destruction, and neoplasia (myxomatous fibroma). Specific immunohistochemistry and polymerase chain reaction for Jaagsiekte sheep retrovirus and enzootic nasal tumor virus were performed with negative results.
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Affiliation(s)
- K A Fox
- Department of Microbiology, Colorado State University, Fort Collins, CO, USA.
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45
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Dagleish M, Benavides J, Chianini F. Immunohistochemical diagnosis of infectious diseases of sheep. Small Rumin Res 2010. [DOI: 10.1016/j.smallrumres.2010.04.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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46
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Griffiths D, Martineau H, Cousens C. Pathology and Pathogenesis of Ovine Pulmonary Adenocarcinoma. J Comp Pathol 2010; 142:260-83. [DOI: 10.1016/j.jcpa.2009.12.013] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 11/28/2009] [Accepted: 12/29/2009] [Indexed: 11/30/2022]
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Côté M, Zheng YM, Liu SL. Receptor binding and low pH coactivate oncogenic retrovirus envelope-mediated fusion. J Virol 2009; 83:11447-55. [PMID: 19726505 PMCID: PMC2772678 DOI: 10.1128/jvi.00748-09] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2009] [Accepted: 08/26/2009] [Indexed: 11/20/2022] Open
Abstract
Fusion of enveloped viruses with host cells is triggered by either receptor binding or low pH but rarely requires both except for avian sarcoma leukosis virus (ASLV). We recently reported that membrane fusion mediated by an oncogenic Jaagsiekte sheep retrovirus (JSRV) envelope (Env) requires an acidic pH, yet receptor overexpression is required for this process to occur. Here we show that a soluble form of the JSRV receptor, sHyal2, promoted JSRV Env-mediated fusion at a low pH in normally fusion-negative cells and that this effect was blocked by a synthetic peptide analogous to the C-terminal heptad repeat of JSRV Env. In contrast to the receptor of ASLV, sHyal2 induced pronounced shedding of the JSRV surface subunit, as well as unstable conformational rearrangement of its transmembrane (TM) subunit, yet full activation of JSRV Env fusogenicity, associated with strong TM oligomerization, required both sHyal2 and low pH. Consistently, sHyal2 enabled transduction of nonpermissive cells by JSRV Env pseudovirions, with low efficiency, but substantially blocked viral entry into permissive cells at both binding and postbinding steps, indicating that sHyal2 prematurely activates JSRV Env-mediated fusion. Altogether, our study supports a model that receptor priming promotes fusion activation of JSRV Env at a low pH, and that the underlying mechanism is likely to be different from that of ASLV. Thus, JSRV may provide a useful alternate model for the better understanding of virus fusion and cell entry.
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Affiliation(s)
- Marceline Côté
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Yi-Min Zheng
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Shan-Lu Liu
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec H3A 2B4, Canada
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48
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Maeda N, Fan H, Yoshikai Y. Oncogenesis by retroviruses: old and new paradigms. Rev Med Virol 2008; 18:387-405. [PMID: 18729235 DOI: 10.1002/rmv.592] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Retroviruses are associated with a variety of diseases including an array of malignancies, immunodeficiencies and neurological disorders. In particular, studies of oncogenic retroviruses established fundamental principles of modern molecular cancer biology. Studies of avian Rous sarcoma virus (RSV) led to the discovery of the viral oncogene src, and this was followed by the discovery of other viral oncogenes in retroviruses of mammals including rodents, cats, monkeys and so forth. Studies of the viral oncogenes in turn led to the discovery of cellular proto-oncogenes in the host genome; cellular oncogenes have been shown to be activated in a variety of human cancers, including those with no viral involvement. Oncogenic animal retroviruses can be divided into two groups based on their mechanisms of tumourigenesis, acute transforming retroviruses and nonacute retroviruses. Acute transforming retroviruses are typically replication defective and they induce tumours rapidly due to expression of their viral oncogenes. Nonacute retroviruses are replication competent and they induce tumours with longer latencies, by activating cellular proto-oncogenes in the tumour cells; this results from insertion of proviral DNA in the vicinity of the activated proto-oncogene. More recently, human T-cell leukaemia virus type I (HTLV-I) was discovered as an etiological agent of human cancer (adult T-cell leukaemia [ATL]); this virus also encodes regulatory genes some of which are important for its oncogenic potential. Most recently, the retroviral structural protein Envelope (Env) has been shown to be directly involved in oncogenic transformation for certain retroviruses. Env-induced transformation is a new paradigm for retroviral oncogenesis. In this review, we will summarise research on retrovirus oncogenic transformation over the past 100 years since the first published report of an oncogenic virus with particular attention to Env-induced transformation.
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Affiliation(s)
- Naoyoshi Maeda
- Division of Host Defense, Research Center for Prevention of Infectious Diseases, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka, Japan.
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49
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Miller AD. Hyaluronidase 2 and its intriguing role as a cell-entry receptor for oncogenic sheep retroviruses. Semin Cancer Biol 2008; 18:296-301. [PMID: 18485731 DOI: 10.1016/j.semcancer.2008.03.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Accepted: 03/19/2008] [Indexed: 10/22/2022]
Abstract
Jaagsiekte sheep retrovirus (JSRV) causes lung adenocarcinoma in sheep and goats, while the closely related enzootic nasal tumor virus (ENTV) causes nasal tumors in the same species. The envelope (Env) protein from either virus can transform fibroblasts and epithelial cells in culture, indicating that the Env proteins are responsible for tumorigenesis. However, the primary function of retroviral Env proteins is to mediate virus entry into cells by interacting with specific cell-surface receptors, suggesting that the virus receptor might be a key player in transformation as well. Thus, identification of Hyaluronidase-2 (Hyal2) as the cell-entry receptor for both JSRV and ENTV suggested a role for Hyal2 in oncogenesis. Furthermore, Hyal2 is located in a key lung cancer tumor suppressor locus on chromosome 3p21.3, suggesting that Hyal2 might have a tumor suppressor activity that was disrupted by Env thereby leading to tumorigenesis. However, recent experiments showing that expression of the JSRV or ENTV Env protein in mouse lung can induce lung tumors, even though the viral Env proteins cannot bind to or utilize mouse Hyal2 as a receptor for virus entry into cells, indicate that Hyal2 plays no role in cancer induction by these retroviruses. Hyal2 remains an enigmatic member of the hyaluronidase family given its very low hyaluronidase activity in purified form or when expressed in cultured cells, suggesting that it may have evolved to perform some other as yet unknown function.
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Affiliation(s)
- A Dusty Miller
- Division of Human Biology, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, WA 98109-1024, USA.
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50
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[New molecular mechanisms of virus-mediated carcinogenesis: oncogenic transformation of cells by retroviral structural protein Envelope]. Uirusu 2008; 57:159-70. [PMID: 18357754 DOI: 10.2222/jsv.57.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
RNA tumor viruses as classified in Retroviruses have been isolated and identified to induce tumors in a variety of animals including chickens, mice, and rats, or even in human in the last 100 years, since the first one has been reported in 1908. The RNA tumor viruses have been historically classified into two groups, acute transforming RNA tumor viruses and nonacute RNA tumor viruses. Acute transforming RNA tumor viruses are basically replication-defective and rapidly induce tumors by expressing the viral oncogenes captured from cellular genome in host cells. The first oncogene derived from Rous sarcoma virus was the src non-receptor tyrosine kinase, which has been identified to play the significant roles for signal transduction. On the other hand, nonacute RNA tumor viruses, which consist of only gag, pro, pol, and env regions but do not carry oncogenes, are replication-competent and could activate the cellular proto-oncogenes by inserting the viral long terminal repeat close to the proto-oncogenes to induce tumors with a long incubation period, as is termed a promoter insertion. These molecular mechanisms have been thought to induce tumors. However, very recently several reports have described that the retroviral structural protein Envelope could directly induce tumors in vivo and transform cells in vitro. These are very unusual examples of native retroviral structural proteins with transformation potential. In this review we look back over the history of oncogenic retrovirus research and summarize recent progress for our understanding of the molecular mechanisms of oncogenic transformation by retrovirus Envelope proteins.
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