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Chou AA, Lin CH, Chang YC, Chang HW, Lin YC, Pi CC, Kan YM, Chuang HF, Chen HW. Antiviral activity of Vigna radiata extract against feline coronavirus in vitro. Vet Q 2024; 44:1-13. [PMID: 38712855 PMCID: PMC11078076 DOI: 10.1080/01652176.2024.2349665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 04/25/2024] [Indexed: 05/08/2024] Open
Abstract
Feline infectious peritonitis (FIP) is a fatal illness caused by a mutated feline coronavirus (FCoV). This disease is characterized by its complexity, resulting from systemic infection, antibody-dependent enhancement (ADE), and challenges in accessing effective therapeutics. Extract derived from Vigna radiata (L.) R. Wilczek (VRE) exhibits various pharmacological effects, including antiviral activity. This study aimed to investigate the antiviral potential of VRE against FCoV, addressing the urgent need to advance the treatment of FIP. We explored the anti-FCoV activity, antiviral mechanism, and combinational application of VRE by means of in vitro antiviral assays. Our findings reveal that VRE effectively inhibited the cytopathic effect induced by FCoV, reduced viral proliferation, and downregulated spike protein expression. Moreover, VRE blocked FCoV in the early and late infection stages and was effective under in vitro ADE infection. Notably, when combined with VRE, the polymerase inhibitor GS-441524 or protease inhibitor GC376 suppressed FCoV more effectively than monotherapy. In conclusion, this study characterizes the antiviral property of VRE against FCoV in vitro, and VRE possesses therapeutic potential for FCoV treatment.
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Affiliation(s)
- Ai-Ai Chou
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Chung-Hui Lin
- National Taiwan University Veterinary Hospital, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Veterinary Clinical Sciences, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
- TACS-alliance Research Center, Taipei, Taiwan
| | - Yen-Chen Chang
- Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Hui-Wen Chang
- Graduate Institute of Molecular and Comparative Pathobiology, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Yi-Chen Lin
- King’s Ground Biotech Co., Ltd., Pingtung, Taiwan
| | - Chia-Chen Pi
- King’s Ground Biotech Co., Ltd., Pingtung, Taiwan
| | - Yao-Ming Kan
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Hao-Fen Chuang
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Hui-Wen Chen
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
- Animal Resource Center, National Taiwan University, Taipei, Taiwan
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2
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Zhu J, Deng S, Mou D, Zhang G, Fu Y, Huang W, Zhang Y, Lyu Y. Analysis of spike and accessory 3c genes mutations of less virulent and FIP-associated feline coronaviruses in Beijing, China. Virology 2024; 589:109919. [PMID: 37939649 DOI: 10.1016/j.virol.2023.109919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 10/13/2023] [Accepted: 10/20/2023] [Indexed: 11/10/2023]
Abstract
Mutations in S and 3c genes of feline coronavirus (FCoV) have been associated with the development of feline infectious peritonitis (FIP). In the present study, FCoV S and 3c genes mutations were analyzed in healthy and FIP cats. M1058L mutation was found in 13.64% (3/22) feces from FIP cats, but not in feces from healthy cats (0/39). The intact 3c gene was found in feces from both healthy cats (19/19) and FIP cats (12/12). All parenteral samples from FIP cats carried one or more of the M1058L mutation, S1060A mutation and mutated 3c gene. FCoV reverse-transcriptase polymerase chain reaction (RT-PCR) of parenteral samples (including ascites, pleural effusions and tissue) is recommended as the gold standard for clinical diagnosis of FIP rather than detection of the M1058L mutation, but when cats have severe gastrointestinal symptoms and lesions, detection of the M1058L mutation in feces may be helpful in diagnosing FIP.
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Affiliation(s)
- Jingru Zhu
- College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Shuqi Deng
- College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Danxia Mou
- College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Gege Zhang
- College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Yingying Fu
- College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Wei Huang
- China Agricultural University Veterinary Teaching Hospital, Beijing, 100193, China
| | - Yueping Zhang
- College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Yanli Lyu
- College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China; China Agricultural University Veterinary Teaching Hospital, Beijing, 100193, China.
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3
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Tasker S, Addie DD, Egberink H, Hofmann-Lehmann R, Hosie MJ, Truyen U, Belák S, Boucraut-Baralon C, Frymus T, Lloret A, Marsilio F, Pennisi MG, Thiry E, Möstl K, Hartmann K. Feline Infectious Peritonitis: European Advisory Board on Cat Diseases Guidelines. Viruses 2023; 15:1847. [PMID: 37766254 PMCID: PMC10535984 DOI: 10.3390/v15091847] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/19/2023] [Accepted: 08/23/2023] [Indexed: 09/29/2023] Open
Abstract
Feline coronavirus (FCoV) is a ubiquitous RNA virus of cats, which is transmitted faeco-orally. In these guidelines, the European Advisory Board on Cat Diseases (ABCD) presents a comprehensive review of feline infectious peritonitis (FIP). FCoV is primarily an enteric virus and most infections do not cause clinical signs, or result in only enteritis, but a small proportion of FCoV-infected cats develop FIP. The pathology in FIP comprises a perivascular phlebitis that can affect any organ. Cats under two years old are most frequently affected by FIP. Most cats present with fever, anorexia, and weight loss; many have effusions, and some have ocular and/or neurological signs. Making a diagnosis is complex and ABCD FIP Diagnostic Approach Tools are available to aid veterinarians. Sampling an effusion, when present, for cytology, biochemistry, and FCoV RNA or FCoV antigen detection is very useful diagnostically. In the absence of an effusion, fine-needle aspirates from affected organs for cytology and FCoV RNA or FCoV antigen detection are helpful. Definitive diagnosis usually requires histopathology with FCoV antigen detection. Antiviral treatments now enable recovery in many cases from this previously fatal disease; nucleoside analogues (e.g., oral GS-441524) are very effective, although they are not available in all countries.
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Affiliation(s)
- Séverine Tasker
- Bristol Veterinary School, University of Bristol, Bristol BS40 5DU, UK
- Linnaeus Veterinary Limited, Shirley, Solihull B90 4BN, UK
| | - Diane D. Addie
- Independent Researcher, 64000 Pyrénées Aquitaine, France;
| | - Herman Egberink
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, 3584 CL Utrecht, The Netherlands;
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland;
| | - Margaret J. Hosie
- MRC-University of Glasgow Centre for Virus Research, Garscube Estate, Glasgow G61 1QH, UK;
| | - Uwe Truyen
- Institute of Animal Hygiene and Veterinary Public Health, University of Leipzig, 04103 Leipzig, Germany;
| | - Sándor Belák
- Department of Biomedical Sciences and Veterinary Public Health (BVF), Swedish University of Agricultural Sciences (SLU), P.O. Box 7036, 750 07 Uppsala, Sweden;
| | | | - Tadeusz Frymus
- Department of Small Animal Diseases with Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, 02-787 Warsaw, Poland;
| | - Albert Lloret
- Fundació Hospital Clínic Veterinari, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain;
| | - Fulvio Marsilio
- Faculty of Veterinary Medicine, Università Degli Studi di Teramo, 64100 Teramo, Italy;
| | - Maria Grazia Pennisi
- Dipartimento di Scienze Veterinarie, Università di Messina, 98168 Messina, Italy;
| | - Etienne Thiry
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, B-4000 Liège, Belgium;
| | - Karin Möstl
- Institute of Virology, Department for Pathobiology, University of Veterinary Medicine, 1210 Vienna, Austria;
| | - Katrin Hartmann
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, 80539 Munich, Germany;
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4
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Le SJ, Xin GY, Wu WC, Shi M. Genetic Diversity and Evolution of Viruses Infecting Felis catus: A Global Perspective. Viruses 2023; 15:1338. [PMID: 37376637 DOI: 10.3390/v15061338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 05/27/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Cats harbor many important viral pathogens, and the knowledge of their diversity has been greatly expanded thanks to increasingly popular molecular sequencing techniques. While the diversity is mostly described in numerous regionally defined studies, there lacks a global overview of the diversity for the majority of cat viruses, and therefore our understanding of the evolution and epidemiology of these viruses was generally inadequate. In this study, we analyzed 12,377 genetic sequences from 25 cat virus species and conducted comprehensive phylodynamic analyses. It revealed, for the first time, the global diversity for all cat viruses known to date, taking into account highly virulent strains and vaccine strains. From there, we further characterized and compared the geographic expansion patterns, temporal dynamics and recombination frequencies of these viruses. While respiratory pathogens such as feline calicivirus showed some degree of geographical panmixes, the other viral species are more geographically defined. Furthermore, recombination rates were much higher in feline parvovirus, feline coronavirus, feline calicivirus and feline foamy virus than the other feline virus species. Collectively, our findings deepen the understanding of the evolutionary and epidemiological features of cat viruses, which in turn provide important insight into the prevention and control of cat pathogens.
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Affiliation(s)
- Shi-Jia Le
- State Key Laboratory for Biocontrol, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
| | - Gen-Yang Xin
- State Key Laboratory for Biocontrol, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
| | - Wei-Chen Wu
- State Key Laboratory for Biocontrol, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
| | - Mang Shi
- State Key Laboratory for Biocontrol, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
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5
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Zehr JD, Kosakovsky Pond SL, Millet JK, Olarte-Castillo XA, Lucaci AG, Shank SD, Ceres KM, Choi A, Whittaker GR, Goodman LB, Stanhope MJ. Natural selection differences detected in key protein domains between non-pathogenic and pathogenic feline coronavirus phenotypes. Virus Evol 2023; 9:vead019. [PMID: 37038392 PMCID: PMC10082545 DOI: 10.1093/ve/vead019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/14/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023] Open
Abstract
Feline coronaviruses (FCoVs) commonly cause mild enteric infections in felines worldwide (termed feline enteric coronavirus [FECV]), with around 12 per cent developing into deadly feline infectious peritonitis (FIP; feline infectious peritonitis virus [FIPV]). Genomic differences between FECV and FIPV have been reported, yet the putative genotypic basis of the highly pathogenic phenotype remains unclear. Here, we used state-of-the-art molecular evolutionary genetic statistical techniques to identify and compare differences in natural selection pressure between FECV and FIPV sequences, as well as to identify FIPV- and FECV-specific signals of positive selection. We analyzed full-length FCoV protein coding genes thought to contain mutations associated with FIPV (Spike, ORF3abc, and ORF7ab). We identified two sites exhibiting differences in natural selection pressure between FECV and FIPV: one within the S1/S2 furin cleavage site (FCS) and the other within the fusion domain of Spike. We also found fifteen sites subject to positive selection associated with FIPV within Spike, eleven of which have not previously been suggested as possibly relevant to FIP development. These sites fall within Spike protein subdomains that participate in host cell receptor interaction, immune evasion, tropism shifts, host cellular entry, and viral escape. There were fourteen sites (twelve novel sites) within Spike under positive selection associated with the FECV phenotype, almost exclusively within the S1/S2 FCS and adjacent to C domain, along with a signal of relaxed selection in FIPV relative to FECV, suggesting that furin cleavage functionality may not be needed for FIPV. Positive selection inferred in ORF7b was associated with the FECV phenotype and included twenty-four positively selected sites, while ORF7b had signals of relaxed selection in FIPV. We found evidence of positive selection in ORF3c in FCoV-wide analyses, but no specific association with the FIPV or FECV phenotype. We hypothesize that some combination of mutations in FECV may contribute to FIP development, and that it is unlikely to be one singular 'switch' mutational event. This work expands our understanding of the complexities of FIP development and provides insights into how evolutionary forces may alter pathogenesis in coronavirus genomes.
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Affiliation(s)
- Jordan D Zehr
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Sergei L Kosakovsky Pond
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Jean K Millet
- Université Paris-Saclay, INRAE, UVSQ, Virologie et Immunologie Moléculaires, Jouy-en-Josas 78352, France
| | - Ximena A Olarte-Castillo
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
- James A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Alexander G Lucaci
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Stephen D Shank
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Kristina M Ceres
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Annette Choi
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Gary R Whittaker
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Laura B Goodman
- James A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Michael J Stanhope
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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6
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Gao YY, Wang Q, Liang XY, Zhang S, Bao D, Zhao H, Li SB, Wang K, Hu GX, Gao FS. An updated review of feline coronavirus: mind the two biotypes. Virus Res 2023; 326:199059. [PMID: 36731629 DOI: 10.1016/j.virusres.2023.199059] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 01/23/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023]
Abstract
Feline coronavirus (FCoV) includes two biotypes: feline infectious peritonitis virus (FIPV) and feline enteric coronavirus (FECV). Although both biotypes can infect cats, their pathogenicities differ. The FIPV biotype is more virulent than the FECV biotype and can cause peritonitis or even death in cats, while most FECV biotypes do not cause lesions. Even pathogenic strains of the FECV biotype can cause only mild enteritis because of their very low virulence. This article reviews recent progress in FCoV research with regard to FCoV etiological characteristics; epidemiology; clinical symptoms and pathological changes; pathogenesis; and current diagnosis, prevention and treatment methods. It is hoped that this review will provide a reference for further research on FCoV and other coronaviruses.
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Affiliation(s)
- Yong-Yu Gao
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China
| | - Qian Wang
- Affiliated Hospital, Changchun University of Chinese Medicine, Changchun, Jilin 130117, China
| | - Xiang-Yu Liang
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China
| | - Shuang Zhang
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China
| | - Di Bao
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China
| | - Han Zhao
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China
| | - Shao-Bai Li
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China
| | - Kai Wang
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China.
| | - Gui-Xue Hu
- Department of Preventive Veterinary Medicine, College of Animal Medicine, Jilin Agricultural University, Xincheng Street 2888, Changchun, Jilin 130118, China.
| | - Feng-Shan Gao
- Department of Bioengineering, College of Life and Health, Dalian University, Xuefu Street 10, Dalian, Liaoning 116622, China; The Dalian Gene and Protein Engineering for Drug Screening Key Laboratory, Dalian 116622, China.
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7
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Mohseni N, Royster A, Ren S, Ma Y, Pintado M, Mir M, Mir S. A novel compound targets the feline infectious peritonitis virus nucleocapsid protein and inhibits viral replication in cell culture. J Biol Chem 2023; 299:102976. [PMID: 36738790 PMCID: PMC10011503 DOI: 10.1016/j.jbc.2023.102976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 01/26/2023] [Accepted: 01/29/2023] [Indexed: 02/05/2023] Open
Abstract
Feline infectious peritonitis (FIP) is a serious viral illness in cats, caused by feline coronavirus. Once a cat develops clinical FIP, the prognosis is poor. The effective treatment strategy for coronavirus infections with immunopathological complications such as SARS-CoV-2, MERS, and FIP is focused on antiviral and immunomodulatory agents to inhibit virus replication and enhance the protective immune response. In this article we report the binding and conformational alteration of feline alphacoronavirus (FCoV) nucleocapsid protein by a novel compound K31. K31 noncompetitively inhibited the interaction between the purified nucleocapsid protein and the synthetic 5' terminus of viral genomic RNA in vitro. K31 was well tolerated by cells and inhibited FCoV replication in cell culture with a selective index of 115. A single dose of K31inhibited FCoV replication to an undetectable level in 24 h post treatment. K31 did not affect the virus entry to the host cell but inhibited the postentry steps of virus replication. The nucleocapsid protein forms ribonucleocapsid in association with the viral genomic RNA that serves as a template for transcription and replication of the viral genome. Our results show that K31 treatment disrupted the structural integrity of ribonucleocapsid in virus-infected cells. After the COVID-19 pandemic, most of the antiviral drug development strategies have focused on RdRp and proteases encoded by the viral genome. Our results have shown that nucleocapsid protein is a druggable target for anticoronavirus drug discovery.
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Affiliation(s)
- Nazleen Mohseni
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, California, USA
| | - Austin Royster
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, California, USA
| | - Songyang Ren
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, California, USA
| | - Yutian Ma
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, California, USA
| | - Melissa Pintado
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, California, USA
| | - Mohammad Mir
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, California, USA
| | - Sheema Mir
- College of Veterinary Medicine, Western University of Health Sciences, Pomona, California, USA.
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8
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Zehr JD, Pond SLK, Millet JK, Olarte-Castillo XA, Lucaci AG, Shank SD, Ceres KM, Choi A, Whittaker GR, Goodman LB, Stanhope MJ. Natural selection differences detected in key protein domains between non-pathogenic and pathogenic Feline Coronavirus phenotypes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.11.523607. [PMID: 36712007 PMCID: PMC9882035 DOI: 10.1101/2023.01.11.523607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Feline Coronaviruses (FCoVs) commonly cause mild enteric infections in felines worldwide (termed Feline Enteric Coronavirus [FECV]), with around 12% developing into deadly Feline Infectious Peritonitis (FIP; Feline Infectious Peritonitis Virus [FIPV]). Genomic differences between FECV and FIPV have been reported, yet the putative genotypic basis of the highly pathogenic phenotype remains unclear. Here, we used state-of-the-art molecular evolutionary genetic statistical techniques to identify and compare differences in natural selection pressure between FECV and FIPV sequences, as well as to identify FIPV and FECV specific signals of positive selection. We analyzed full length FCoV protein coding genes thought to contain mutations associated with FIPV (Spike, ORF3abc, and ORF7ab). We identified two sites exhibiting differences in natural selection pressure between FECV and FIPV: one within the S1/S2 furin cleavage site, and the other within the fusion domain of Spike. We also found 15 sites subject to positive selection associated with FIPV within Spike, 11 of which have not previously been suggested as possibly relevant to FIP development. These sites fall within Spike protein subdomains that participate in host cell receptor interaction, immune evasion, tropism shifts, host cellular entry, and viral escape. There were 14 sites (12 novel) within Spike under positive selection associated with the FECV phenotype, almost exclusively within the S1/S2 furin cleavage site and adjacent C domain, along with a signal of relaxed selection in FIPV relative to FECV, suggesting that furin cleavage functionality may not be needed for FIPV. Positive selection inferred in ORF7b was associated with the FECV phenotype, and included 24 positively selected sites, while ORF7b had signals of relaxed selection in FIPV. We found evidence of positive selection in ORF3c in FCoV wide analyses, but no specific association with the FIPV or FECV phenotype. We hypothesize that some combination of mutations in FECV may contribute to FIP development, and that is unlikely to be one singular "switch" mutational event. This work expands our understanding of the complexities of FIP development and provides insights into how evolutionary forces may alter pathogenesis in coronavirus genomes.
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Affiliation(s)
- Jordan D. Zehr
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Sergei L. Kosakovsky Pond
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Jean K. Millet
- Université Paris-Saclay, INRAE, UVSQ, Virologie et Immunologie Moléculaires, 78352 Jouyen-Josas, France
| | - Ximena A. Olarte-Castillo
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
| | - Alexander G. Lucaci
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Stephen D. Shank
- Department of Biology, Temple University, Institute for Genomics and Evolutionary Medicine, Philadelphia, PA 19122, USA
| | - Kristina M. Ceres
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Annette Choi
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Gary R. Whittaker
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- Department of Microbiology & Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Laura B. Goodman
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- James A. Baker Institute for Animal Health, Cornell University College of Veterinary Medicine, Ithaca, NY, 14853, USA
| | - Michael J. Stanhope
- Department of Public and Ecosystem Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
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Thayer V, Gogolski S, Felten S, Hartmann K, Kennedy M, Olah GA. 2022 AAFP/EveryCat Feline Infectious Peritonitis Diagnosis Guidelines. J Feline Med Surg 2022; 24:905-933. [PMID: 36002137 PMCID: PMC10812230 DOI: 10.1177/1098612x221118761] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
CLINICAL IMPORTANCE Feline infectious peritonitis (FIP) is one of the most important infectious diseases and causes of death in cats; young cats less than 2 years of age are especially vulnerable. FIP is caused by a feline coronavirus (FCoV). It has been estimated that around 0.3% to 1.4% of feline deaths at veterinary institutions are caused by FIP. SCOPE This document has been developed by a Task Force of experts in feline clinical medicine as the 2022 AAFP/EveryCat Feline Infectious Peritonitis Diagnosis Guidelines to provide veterinarians with essential information to aid their ability to recognize cats presenting with FIP. TESTING AND INTERPRETATION Nearly every small animal veterinary practitioner will see cases. FIP can be challenging to diagnose owing to the lack of pathognomonic clinical signs or laboratory changes, especially when no effusion is present. A good understanding of each diagnostic test's sensitivity, specificity, predictive value, likelihood ratio and diagnostic accuracy is important when building a case for FIP. Before proceeding with any diagnostic test or commercial laboratory profile, the clinician should be able to answer the questions of 'why this test?' and 'what do the results mean?' Ultimately, the approach to diagnosing FIP must be tailored to the specific presentation of the individual cat. RELEVANCE Given that the disease is fatal when untreated, the ability to obtain a correct diagnosis is critical. The clinician must consider the individual patient's history, signalment and comprehensive physical examination findings when selecting diagnostic tests and sample types in order to build the index of suspicion 'brick by brick'. Research has demonstrated efficacy of new antivirals in FIP treatment, but these products are not legally available in many countries at this time. The Task Force encourages veterinarians to review the literature and stay informed on clinical trials and new drug approvals.
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Tuanthap S, Chiteafea N, Rattanasrisomporn J, Choowongkomon K. Comparative sequence analysis of the accessory and nucleocapsid genes of feline coronavirus strains isolated from cats diagnosed with effusive feline infectious peritonitis. Arch Virol 2021; 166:2779-2787. [PMID: 34363535 PMCID: PMC8346774 DOI: 10.1007/s00705-021-05188-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/08/2021] [Indexed: 01/19/2023]
Abstract
Feline infectious peritonitis (FIP) is a lethal infectious disease of domestic cats caused by feline coronavirus (FCoV) infection. Feline infectious peritonitis virus (FIPV) is a mutant type of FCoV that is characterized by causing fibrinous serositis with effusions in the pleural and abdominal cavities (wet form) and/or granulomatous-necrotizing inflammatory lesions in several organs (dry form). There have been numerous studies on FIP worldwide, whereas information about this disease in Thailand is still limited. Most studies involving molecular surveillance and evaluation of FCoV field strains have examined the genetic diversity of the spike and accessory ORF3c coding regions. Of these, the S gene is more divergent and is responsible for the two FCoV serotypes, while ORF3c harbors mutations that result either in early termination or destruction of the protein. In this study, we investigated the genetic diversity and genetic relationships among the current Thai and global FCoV strains in the accessory and nucleocapsid genes using a virus-specific PCR method. Comparative sequence analysis suggested that the Thai FCoV isolates were most closely related to strains reported in the Netherlands, the USA, and China. In the ORF3ab sequences, some Thai strains were more than 99% identical to the DF-2 prototype strain. Truncation of the 3a gene product was found in Thai FCoV strains of group 2. Amino acid deletions were observed in the N, ORF3c, and ORF7b proteins of Thai FCoV sequences. The accessory gene sequence divergence may be responsible for driving the periodic emergence and continued persistence of FCoVs in Thai domestic cat populations. Our findings provide updated information about the molecular characteristics of the accessory and nucleocapsid genes of FCoV strains in circulation that were not previously documented in this country.
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Affiliation(s)
- Supansa Tuanthap
- Department of Biochemistry, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand
- Department of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, 10900, Thailand
| | - Natdaroon Chiteafea
- Department of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, 10900, Thailand
| | - Jatuporn Rattanasrisomporn
- Department of Companion Animal Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, 10900, Thailand.
| | - Kiattawee Choowongkomon
- Department of Biochemistry, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand.
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11
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Lutz M, Steiner AR, Cattori V, Hofmann-Lehmann R, Lutz H, Kipar A, Meli ML. FCoV Viral Sequences of Systemically Infected Healthy Cats Lack Gene Mutations Previously Linked to the Development of FIP. Pathogens 2020; 9:E603. [PMID: 32722056 PMCID: PMC7459962 DOI: 10.3390/pathogens9080603] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/19/2020] [Accepted: 07/20/2020] [Indexed: 01/21/2023] Open
Abstract
Feline infectious peritonitis (FIP)-the deadliest infectious disease of young cats in shelters or catteries-is induced by highly virulent feline coronaviruses (FCoVs) emerging in infected hosts after mutations of less virulent FCoVs. Previous studies have shown that some mutations in the open reading frames (ORF) 3c and 7b and the spike (S) gene have implications for the development of FIP, but mainly indirectly, likely also due to their association with systemic spread. The aim of the present study was to determine whether FCoV detected in organs of experimentally FCoV infected healthy cats carry some of these mutations. Viral RNA isolated from different tissues of seven asymptomatic cats infected with the field strains FCoV Zu1 or FCoV Zu3 was sequenced. Deletions in the 3c gene and mutations in the 7b and S genes that have been shown to have implications for the development of FIP were not detected, suggesting that these are not essential for systemic viral dissemination. However, deletions and single nucleotide polymorphisms leading to truncations were detected in all nonstructural proteins. These were found across all analyzed ORFs, but with significantly higher frequency in ORF 7b than ORF 3a. Additionally, a previously unknown homologous recombination site was detected in FCoV Zu1.
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Affiliation(s)
- Mirjam Lutz
- Clinical Laboratory, Department of Clinical Diagnostics and Services and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH 8057 Zurich, Switzerland; (M.L.); (A.R.S.); (V.C.); (R.H.-L.); (H.L.)
| | - Aline R. Steiner
- Clinical Laboratory, Department of Clinical Diagnostics and Services and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH 8057 Zurich, Switzerland; (M.L.); (A.R.S.); (V.C.); (R.H.-L.); (H.L.)
| | - Valentino Cattori
- Clinical Laboratory, Department of Clinical Diagnostics and Services and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH 8057 Zurich, Switzerland; (M.L.); (A.R.S.); (V.C.); (R.H.-L.); (H.L.)
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH 8057 Zurich, Switzerland; (M.L.); (A.R.S.); (V.C.); (R.H.-L.); (H.L.)
| | - Hans Lutz
- Clinical Laboratory, Department of Clinical Diagnostics and Services and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH 8057 Zurich, Switzerland; (M.L.); (A.R.S.); (V.C.); (R.H.-L.); (H.L.)
| | - Anja Kipar
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, CH 8057 Zurich, Switzerland;
| | - Marina L. Meli
- Clinical Laboratory, Department of Clinical Diagnostics and Services and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, CH 8057 Zurich, Switzerland; (M.L.); (A.R.S.); (V.C.); (R.H.-L.); (H.L.)
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12
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Myrrha LW, Silva FMF, Vidigal PMP, Resende M, Bressan GC, Fietto JLR, Santos MR, Silva LMN, Assao VS, Silva-Jú Nior A, de Almeida MR. Feline coronavirus isolates from a part of Brazil: insights into molecular epidemiology and phylogeny inferred from the 7b gene. J Vet Med Sci 2019; 81:1455-1460. [PMID: 31447457 PMCID: PMC6863716 DOI: 10.1292/jvms.19-0090] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The Feline coronavirus (FCoV) can lead to Feline infectious peritonitis (FIP), which the precise cause is still unknown. The theory of internal mutation suggests that a less virulent biotype of FCoV (FECV) would lead to another more pathogenic biotype (FIPV) capable of causing FIP. In this work, the 7b gene was amplified from 51 domestic cat plasma samples by semi-nested PCR and tested through phylogenetic and phylogeographical approaches. The 7b gene of Brazilian isolates displayed high conservation, a strong correlation between the geographic origin of the viral isolates and their genealogy, and its evolution was possibly shaped by a combination of high rates of nucleotide substitution and purifying selection.
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Affiliation(s)
- Luciana Wanderley Myrrha
- Laboratory of Animal Molecular Infectology, Institute of Biotechnology Applied to Agriculture, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Fernanda Miquelitto Figueira Silva
- Laboratory of Animal Molecular Infectology, Institute of Biotechnology Applied to Agriculture, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Pedro Marcus Pereira Vidigal
- Nucleus of Analysis of Biomolecules, Center of Biological Sciences, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Maurício Resende
- Departament of Microbiology, Federal University of Minas Gerais (UFMG), Belo Horizonte, Minas Gerais 31275-035, Brazil
| | - Gustavo Costa Bressan
- Laboratory of Animal Molecular Infectology, Institute of Biotechnology Applied to Agriculture, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Juliana Lopes Rangel Fietto
- Laboratory of Animal Molecular Infectology, Institute of Biotechnology Applied to Agriculture, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Marcus Rebouças Santos
- Laboratory of Immunobiological and Animal Virology, Departament of Veterinary, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Laura Morais Nascimento Silva
- Laboratory of Immunobiological and Animal Virology, Departament of Veterinary, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Viviane Sisdelli Assao
- Laboratory of Immunobiological and Animal Virology, Departament of Veterinary, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Abelardo Silva-Jú Nior
- Laboratory of Immunobiological and Animal Virology, Departament of Veterinary, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
| | - Márcia Rogéria de Almeida
- Laboratory of Animal Molecular Infectology, Institute of Biotechnology Applied to Agriculture, Federal University of Viçosa (UFV), Viçosa, Minas Gerais 36570-900, Brazil
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Barker EN, Stranieri A, Helps CR, Porter EL, Davidson AD, Day MJ, Knowles T, Kipar A, Tasker S. Limitations of using feline coronavirus spike protein gene mutations to diagnose feline infectious peritonitis. Vet Res 2017; 48:60. [PMID: 28982390 PMCID: PMC5629788 DOI: 10.1186/s13567-017-0467-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 09/15/2017] [Indexed: 12/23/2022] Open
Abstract
Feline infectious peritonitis (FIP) is a fatal disease of cats, and a sequela of systemic feline coronavirus (FCoV) infection. Mutations in the viral spike (S) gene have been associated with FCoVs found in tissues from cats with FIP, but not FCoVs found in faeces from healthy cats, and are implicated in monocyte/macrophage tropism and systemic spread. This study was designed to determine whether S gene mutation analysis can reliably diagnose FIP. Cats were categorised as with FIP (n = 57) or without FIP (n = 45) based on gross post-mortem and histopathological examination including immunohistochemistry for FCoV antigen. RNA was purified from available tissue, fluid and faeces. Reverse-transcriptase quantitative-PCR (RT-qPCR) was performed on all samples using FCoV-specific primers, followed by sequencing of a section of the S gene on RT-qPCR positive samples. Samples were available from a total of 102 cats. Tissue, fluid, and faecal samples from cats with FIP were more likely to be FCoV RT-qPCR-positive (90.4, 78.4 and 64.6% respectively) than those from cats without FIP (7.8, 2.1 and 20% respectively). Identification of S gene mutated FCoVs as an additional step to the detection of FCoV alone, only moderately increased specificity for tissue samples (from 92.6 to 94.6%) but specificity was unchanged for fluid samples (97.9%) for FIP diagnosis; however, sensitivity was markedly decreased for tissue (from 89.8 to 80.9%) and fluid samples (from 78.4 to 60%) for FIP diagnosis. These findings demonstrate that S gene mutation analysis in FCoVs does not substantially improve the ability to diagnose FIP as compared to detection of FCoV alone.
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Affiliation(s)
- Emily N Barker
- School of Veterinary Sciences, University of Bristol, Bristol, UK.
| | | | - Chris R Helps
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Emily L Porter
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Andrew D Davidson
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Michael J Day
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Toby Knowles
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Anja Kipar
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.,Institute of Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK
| | - Séverine Tasker
- School of Veterinary Sciences, University of Bristol, Bristol, UK
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14
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Felten S, Weider K, Doenges S, Gruendl S, Matiasek K, Hermanns W, Mueller E, Matiasek L, Fischer A, Weber K, Hirschberger J, Wess G, Hartmann K. Detection of feline coronavirus spike gene mutations as a tool to diagnose feline infectious peritonitis. J Feline Med Surg 2017; 19:321-335. [PMID: 26701958 PMCID: PMC11119656 DOI: 10.1177/1098612x15623824] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Objectives Feline infectious peritonitis (FIP) is an important cause of death in the cat population worldwide. The ante-mortem diagnosis of FIP in clinical cases is still challenging. In cats without effusion, a definitive diagnosis can only be achieved post mortem or with invasive methods. The aim of this study was to evaluate the use of a combined reverse transcriptase nested polymerase chain reaction (RT-nPCR) and sequencing approach in the diagnosis of FIP, detecting mutations at two different nucleotide positions within the spike (S) gene. Methods The study population consisted of 64 cats with confirmed FIP and 63 cats in which FIP was initially suspected due to similar clinical or laboratory signs, but that were definitively diagnosed with another disease. Serum/plasma and/or effusion samples of these cats were examined for feline coronavirus (FCoV) RNA by RT-nPCR and, if positive, PCR products were sequenced for nucleotide transitions within the S gene. Results Specificity of RT-nPCR was 100% in all materials (95% confidence interval [CI] in serum/plasma 83.9-100.0; 95% CI in effusion 93.0-100.0). The specificity of the sequencing step could not be determined as none of the cats of the control group tested positive for FCoV RNA. Sensitivity of the 'combined RT-nPCR and sequencing approach' was 6.5% (95% CI 0.8-21.4) in serum/plasma and 65.3% (95% CI 50.4-78.3) in effusion. Conclusions and relevance A positive result is highly indicative of the presence of FIP, but as none of the control cats tested positive by RT-nPCR, it was not possible to confirm that the FCoV mutant described can only be found in cats with FIP. Further studies are necessary to evaluate the usefulness of the sequencing step including FCoV-RNA-positive cats with and without FIP. A negative result cannot be used to exclude the disease, especially when only serum/plasma samples are available.
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Affiliation(s)
- Sandra Felten
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | | | - Stephanie Doenges
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Stefanie Gruendl
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Kaspar Matiasek
- Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Walter Hermanns
- Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | | | - Lara Matiasek
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Andrea Fischer
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Karin Weber
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Johannes Hirschberger
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Gerhard Wess
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Katrin Hartmann
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
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15
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Feline Coronavirus 3c Protein: A Candidate for a Virulence Marker? BIOMED RESEARCH INTERNATIONAL 2016; 2016:8560691. [PMID: 27243037 PMCID: PMC4868892 DOI: 10.1155/2016/8560691] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 04/01/2016] [Accepted: 04/10/2016] [Indexed: 11/17/2022]
Abstract
Feline infectious peritonitis virus (FIPV) is highly virulent and responsible for the highly fatal disease feline infectious peritonitis (FIP), whereas feline enteric coronavirus (FECV) is widespread among the feline population and typically causes asymptomatic infections. Some candidates for genetic markers capable of differentiating these two pathotypes of a unique virus (feline coronavirus) have been proposed by several studies. In the present survey, in order to search for markers that can differentiate FECV and FIPV, several clones of the 3a–c, E, and M genes were sequenced from samples obtained from cats with or without FIP. All genes showed genetic diversity and suggested the presence of FCoV mutant spectrum capable of producing a virulent pathotype in an individual-specific way. In addition, all the feline coronavirus FIPV strains demonstrated a truncated 3c protein, and the 3c gene was the only observed pathotypic marker for FCoVs, showing that 3c gene is a candidate marker for the distinction between the two pathotypes when the mutant spectrum is taken into account.
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16
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Lewis CS, Porter E, Matthews D, Kipar A, Tasker S, Helps CR, Siddell SG. Genotyping coronaviruses associated with feline infectious peritonitis. J Gen Virol 2015; 96:1358-1368. [PMID: 25667330 PMCID: PMC4635486 DOI: 10.1099/vir.0.000084] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 02/03/2015] [Indexed: 12/21/2022] Open
Abstract
Feline coronavirus (FCoV) infections are endemic among cats worldwide. The majority of infections are asymptomatic or result in only mild enteric disease. However, approximately 5 % of cases develop feline infectious peritonitis (FIP), a systemic disease that is a frequent cause of death in young cats. In this study, we report the complete coding genome sequences of six FCoVs: three from faecal samples from healthy cats and three from tissue lesion samples from cats with confirmed FIP. The six samples were obtained over a period of 8 weeks at a single-site cat rescue and rehoming centre in the UK. We found amino acid differences located at 44 positions across an alignment of the six virus translatomes and, at 21 of these positions, the differences fully or partially discriminated between the genomes derived from the faecal samples and the genomes derived from the tissue lesion samples. In this study, two amino acid differences fully discriminated the two classes of genomes: these were both located in the S2 domain of the virus surface glycoprotein gene. We also identified deletions in the 3c protein ORF of genomes from two of the FIP samples. Our results support previous studies that implicate S protein mutations in the pathogenesis of FIP.
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Affiliation(s)
- Catherine S Lewis
- School of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK
| | - Emily Porter
- School of Veterinary Sciences, University of Bristol, Langford, Bristol BS40 5DU, UK
| | - David Matthews
- School of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK
| | - Anja Kipar
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Winterthurer Strasse 268, 8057 Zurich, Switzerland
| | - Séverine Tasker
- School of Veterinary Sciences, University of Bristol, Langford, Bristol BS40 5DU, UK
| | - Christopher R Helps
- School of Veterinary Sciences, University of Bristol, Langford, Bristol BS40 5DU, UK
| | - Stuart G Siddell
- School of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK
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17
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Porter E, Tasker S, Day MJ, Harley R, Kipar A, Siddell SG, Helps CR. Amino acid changes in the spike protein of feline coronavirus correlate with systemic spread of virus from the intestine and not with feline infectious peritonitis. Vet Res 2014; 45:49. [PMID: 24767677 PMCID: PMC4006447 DOI: 10.1186/1297-9716-45-49] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 04/07/2014] [Indexed: 11/19/2022] Open
Abstract
Recent evidence suggests that a mutation in the spike protein gene of feline coronavirus (FCoV), which results in an amino acid change from methionine to leucine at position 1058, may be associated with feline infectious peritonitis (FIP). Tissue and faecal samples collected post mortem from cats diagnosed with or without FIP were subjected to RNA extraction and quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) to detect FCoV RNA. In cats with FIP, 95% of tissue, and 81% of faecal samples were PCR-positive, as opposed to 22% of tissue, and 60% of faecal samples in cats without FIP. Relative FCoV copy numbers were significantly higher in the cats with FIP, both in tissues (P < 0.001) and faeces (P = 0.02). PCR-positive samples underwent pyrosequencing encompassing position 1058 of the FCoV spike protein. This identified a methionine codon at position 1058, consistent with the shedding of an enteric form of FCoV, in 77% of the faecal samples from cats with FIP, and in 100% of the samples from cats without FIP. In contrast, 91% of the tissue samples from cats with FIP and 89% from cats without FIP had a leucine codon at position 1058, consistent with a systemic form of FCoV. These results suggest that the methionine to leucine substitution at position 1058 in the FCoV spike protein is indicative of systemic spread of FCoV from the intestine, rather than a virus with the potential to cause FIP.
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Affiliation(s)
| | | | | | | | | | - Stuart G Siddell
- School of Cellular and Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK.
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Intrahost diversity of feline coronavirus: a consensus between the circulating virulent/avirulent strains and the internal mutation hypotheses? ScientificWorldJournal 2013; 2013:572325. [PMID: 23589704 PMCID: PMC3622387 DOI: 10.1155/2013/572325] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Accepted: 02/28/2013] [Indexed: 11/22/2022] Open
Abstract
To evaluate the most controversial issue concerning current feline coronavirus (FCoV) virology, the coexisting hypotheses of the intrahost and interhost origins of feline infectious peritonitis virus (FIPV) in regard to the pathogenesis of feline infectious peritonitis (FIP), this study aimed to assess the molecular diversity of the membrane gene FCoVs in 190 samples from 10 cats with signs of FIP and in 5 faecal samples from cats without signs of FIP. All samples from the non-FIP cats and 25.26% of the samples from the FIP cats were positive for the FCoV membrane (M) gene. Mutations in this gene consisted of SNP changes randomly scattered among the sequences; few mutations resulted in amino acid changes. No geographic pattern was observed. Of the cats without FIP that harboured FECoV, the amino acid sequence identities for the M gene were 100% among cats (Cats 1–3) from the same cattery, and the overall sequence identity for the M gene was ≥91%. In one cat, two different lineages of FCoV, one enteric and one systemic, were found that segregated apart in the M gene tree. In conclusion, the in vivo mutation transition hypothesis and the circulating high virulent-low virulent FCoV hypothesis have been found to be plausible according to the results obtained from sequencing the M gene.
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Full genome analysis of a novel type II feline coronavirus NTU156. Virus Genes 2012; 46:316-22. [PMID: 23239278 PMCID: PMC7089305 DOI: 10.1007/s11262-012-0864-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 12/03/2012] [Indexed: 01/09/2023]
Abstract
Infections by type II feline coronaviruses (FCoVs) have been shown to be significantly correlated with fatal feline infectious peritonitis (FIP). Despite nearly six decades having passed since its first emergence, different studies have shown that type II FCoV represents only a small portion of the total FCoV seropositivity in cats; hence, there is very limited knowledge of the evolution of type II FCoV. To elucidate the correlation between viral emergence and FIP, a local isolate (NTU156) that was derived from a FIP cat was analyzed along with other worldwide strains. Containing an in-frame deletion of 442 nucleotides in open reading frame 3c, the complete genome size of NTU156 (28,897 nucleotides) appears to be the smallest among the known type II feline coronaviruses. Bootscan analysis revealed that NTU156 evolved from two crossover events between type I FCoV and canine coronavirus, with recombination sites located in the RNA-dependent RNA polymerase and M genes. With an exchange of nearly one-third of the genome with other members of alphacoronaviruses, the new emerging virus could gain new antigenicity, posing a threat to cats that either have been infected with a type I virus before or never have been infected with FCoV.
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20
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Molecular characterization of feline infectious peritonitis virus strain DF-2 and studies of the role of ORF3abc in viral cell tropism. J Virol 2012; 86:6258-67. [PMID: 22438554 DOI: 10.1128/jvi.00189-12] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The full-length genome of the highly lethal feline infectious peritonitis virus (FIPV) strain DF-2 was sequenced and cloned into a bacterial artificial chromosome (BAC) to study the role of ORF3abc in the FIPV-feline enteric coronavirus (FECV) transition. The reverse genetic system allowed the replacement of the truncated ORF3abc of the original FIPV DF-2 genome with the intact ORF3abc of the canine coronavirus (CCoV) reference strain Elmo/02. The in vitro replication kinetics of these two viruses was studied in CrFK and FCWF-4 cell lines, as well as in feline peripheral blood monocytes. Both viruses showed similar replication kinetics in established cell lines. However, the strain with a full-length ORF3 showed markedly lower replication of more than 2 log(10) titers in feline peripheral blood monocytes. Our results suggest that the truncated ORF3abc plays an important role in the efficient macrophage/monocyte tropism of type II FIPV.
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Feline infectious peritonitis: role of the feline coronavirus 3c gene in intestinal tropism and pathogenicity based upon isolates from resident and adopted shelter cats. Virus Res 2012; 165:17-28. [PMID: 22280883 PMCID: PMC7114484 DOI: 10.1016/j.virusres.2011.12.020] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 12/27/2011] [Accepted: 12/28/2011] [Indexed: 11/22/2022]
Abstract
Feline infectious peritonitis virus (FIPV) was presumed to arise from mutations in the 3c of a ubiquitous and largely nonpathogenic feline enteric coronavirus (FECV). However, a recent study found that one-third of FIPV isolates have an intact 3c and suggested that it is not solely involved in FIP but is essential for intestinal replication. In order to confirm these assumptions, 27 fecal and 32 FIP coronavirus isolates were obtained from resident or adopted cats from a large metropolitan shelter during 2008-2009 and their 3a-c, E, and M genes sequenced. Forty percent of coronavirus isolates from FIP tissues had an intact 3c gene, while 60% had mutations that truncated the gene product. The 3c genes of fecal isolates from healthy cats were always intact. Coronavirus from FIP diseased tissues consistently induced FIP when given either oronasally or intraperitoneally (i.p.), regardless of the functional status of their 3c genes, thus confirming them to be FIPVs. In contrast, fecal isolates from healthy cats were infectious following oronasal infection and shed at high levels in feces without causing disease, as expected for FECVs. Only one in three cats shed FECV in the feces following i.p. infection, indicating that FECVs can replicate systemically, but with difficulty. FIPVs having a mutated 3c were not shed in the feces following either oronasal or i.p. inoculation, while FIPVs with intact 3c genes were shed in the feces following oronasal but not i.p. inoculation. Therefore, an intact 3c appears to be essential for intestinal replication. Although FIPVs with an intact 3c were shed in the feces following oronasal inoculation, fecal virus from these cats was not infectious for other cats. Attempts to identify potential FIP mutations in the 3a, 3b, E, and M were negative. However, the 3c gene of FIPVs, even though appearing intact, contained many more non-synonymous amino acid changes in the 3' one-third of the 3c protein than FECVs. An attempt to trace FIPV isolates back to enteric strains existing in the shelter was only partially successful due to the large region over which shelter cats and kittens originated, housing conditions prior to acquisition, and rapid movement through the shelter. No evidence could be found to support a recent theory that FIPVs and FECVs are genetically distinct.
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Infectious Diseases. THE CAT 2012. [PMCID: PMC7161403 DOI: 10.1016/b978-1-4377-0660-4.00033-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Myrrha LW, Silva FMF, Peternelli EFDO, Junior AS, Resende M, de Almeida MR. The paradox of feline coronavirus pathogenesis: a review. Adv Virol 2011; 2011:109849. [PMID: 22312333 PMCID: PMC3265210 DOI: 10.1155/2011/109849] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 06/01/2011] [Accepted: 06/01/2011] [Indexed: 12/04/2022] Open
Abstract
Feline coronavirus (FCoV) is an enveloped single-stranded RNA virus, of the family Coronaviridae and the order Nidovirales. FCoV is an important pathogen of wild and domestic cats and can cause a mild or apparently symptomless enteric infection, especially in kittens. FCoV is also associated with a lethal, systemic disease known as feline infectious peritonitis (FIP). Although the precise cause of FIP pathogenesis remains unclear, some hypotheses have been suggested. In this review we present results from different FCoV studies and attempt to elucidate existing theories on the pathogenesis of FCoV infection.
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Affiliation(s)
- Luciana Wanderley Myrrha
- Laboratório de Infectologia Molecular Animal (LIMA), Universidade Federal de Viçosa, Avenida Peter Henry Rolfs, s/n Campus Universitário, 36570-000 Vicosa, MG, Brazil
| | - Fernanda Miquelitto Figueira Silva
- Laboratório de Infectologia Molecular Animal (LIMA), Universidade Federal de Viçosa, Avenida Peter Henry Rolfs, s/n Campus Universitário, 36570-000 Vicosa, MG, Brazil
| | - Ethel Fernandes de Oliveira Peternelli
- Laboratório de Infectologia Molecular Animal (LIMA), Universidade Federal de Viçosa, Avenida Peter Henry Rolfs, s/n Campus Universitário, 36570-000 Vicosa, MG, Brazil
| | - Abelardo Silva Junior
- Laboratório de Infectologia Molecular Animal (LIMA), Universidade Federal de Viçosa, Avenida Peter Henry Rolfs, s/n Campus Universitário, 36570-000 Vicosa, MG, Brazil
| | - Maurício Resende
- Laboratório de Doença das Aves, Universidade Federal de Minas Gerais, Avenida Antônio Carlos, 6627—Pampulha, 31270-901, Belo Horizonte, MG, Brazil
| | - Márcia Rogéria de Almeida
- Laboratório de Infectologia Molecular Animal (LIMA), Universidade Federal de Viçosa, Avenida Peter Henry Rolfs, s/n Campus Universitário, 36570-000 Vicosa, MG, Brazil
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Abstract
Feline infectious peritonitis (FIP) is a fatal, immune-augmented, and progressive viral disease of cats associated with feline coronavirus (FCoV). Viral genetic determinants specifically associated with FIPV pathogenesis have not yet been discovered. Viral gene signatures in the spike, non-structural protein 3c, and membrane of the coronavirus genome have been shown to often correlate with disease manifestation. An “in vivo mutation transition hypothesis” is widely accepted and postulates that de novo virus mutation occurs in vivo giving rise to virulence. The existence of “distinct circulating avirulent and virulent strains” is an alternative hypothesis of viral pathogenesis. It may be possible that viral dynamics from both hypotheses are at play in the occurrence of FIP. Epidemiologic data suggests that the genetic background of the cat contributes to the manifestation of FIP. Further studies exploring both viral and host genetic determinants of disease in FIP offer specific opportunities for the management of this disease.
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Affiliation(s)
- Meredith A Brown
- New Mexico State University, Department of Biology, Las Cruces, NM 88003-8001, USA.
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25
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Rossi G, Cornaro C, Battilani M, Pocacqua V, Paltrinieri S. Production of IFN-γ in feline whole blood after incubation with potential T-cell epitopes of the nucleocapsid protein of feline coronavirus. Vet Microbiol 2011; 150:248-56. [PMID: 21376481 PMCID: PMC7117359 DOI: 10.1016/j.vetmic.2011.02.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 12/20/2010] [Accepted: 02/08/2011] [Indexed: 11/30/2022]
Abstract
Interferon gamma (IFN-γ) plays an important role in cell mediated responses against mutated feline coronavirus strains (FCoV) involved in the pathogenesis of feline infectious peritonitis (FIP). The aim of this study was to establish a combined in silico and in vitro approach to assess feline leukocyte production of IFN-γ in response to selected peptides of the nucleocapside protein (N) of FCoVs. To this aim, we designed, through a bioinformatic approach, 8 potentially immunogenic peptides from the protein N corresponding to sequences of residues 14, 182, 198 detected only in FCoVs from FIP cats (virulent strains), only in FCoVs from healthy cats (avirulent strains) and both in FIP and in healthy cats (mixed strains). The peptides or a sham solution were incubated with whole blood from 16 cats (7 healthy and 9 with chronic diseases other than FIP) and IFN-γ concentration was measured on plasma using an ELISA system. RT-PCR expression of IFN-γ mRNA was also evaluated after incubation of the peptides or a sham solution with whole blood from 4 clinically healthy cats. The mean plasma concentration of IFN-γ in samples incubated with peptides decreased and the expression of IFN-γmRNA did not change compared with the sham solution, except for some cats with chronic diseases (which probably have a “pre-activated” immune response). These cats responded to “avirulent” or “mixed” peptides by increasing the concentration of IFN-γ and the expression of IFN-γ mRNA. The combined approach employed in this study allowed us to identify potentially immunogenic peptides of FCoV N protein that can modulate the production of IFN-γ especially in cats with a “pre-activated” cell mediated response.
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Affiliation(s)
- G Rossi
- Department of Veterinary Pathology, Hygiene and Public Health, Unit of Veterinary General Pathology and Parasitology, University of Milan, Via Celoria 10, 20133 Milan, Italy
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Chang HW, de Groot RJ, Egberink HF, Rottier PJM. Feline infectious peritonitis: insights into feline coronavirus pathobiogenesis and epidemiology based on genetic analysis of the viral 3c gene. J Gen Virol 2010; 91:415-20. [PMID: 19889934 DOI: 10.1099/vir.0.016485-0] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Feline infectious peritonitis (FIP) is a lethal systemic disease caused by FIP virus (FIPV), a virulent mutant of apathogenic feline enteric coronavirus (FECV). We analysed the 3c gene--a proposed virulence marker--in 27 FECV- and 28 FIPV-infected cats. Our findings suggest that functional 3c protein expression is crucial for FECV replication in the gut, but dispensable for systemic FIPV replication. Whilst intact in all FECVs, the 3c gene was mutated in the majority (71.4 %) of FIPVs, but not in all, implying that mutation in 3c is not the (single) cause of FIP. Most cats with FIP had no detectable intestinal feline coronaviruses (FCoVs) and had seemingly cleared the primary FECV infection. In those with detectable intestinal FCoV, the virus always had an intact 3c and seemed to have been acquired by FECV superinfection. Apparently, 3c-inactivated viruses replicate not at all--or only poorly--in the gut, explaining the rare incidence of FIP outbreaks.
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Affiliation(s)
- Hui-Wen Chang
- Virology Division, Department of Infectious Diseases and Immunology, Veterinary Faculty, Utrecht University, Utrecht, The Netherlands
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27
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Brown MA, Troyer JL, Pecon-Slattery J, Roelke ME, O'Brien SJ. Genetics and pathogenesis of feline infectious peritonitis virus. Emerg Infect Dis 2010; 15:1445-52. [PMID: 19788813 PMCID: PMC2819880 DOI: 10.3201/eid1509.081573] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Coronavirus sequence analyses demonstrate distinctive circulating strains in natural populations. Feline coronavirus (FCoV) is endemic in feral cat populations and cat colonies, frequently preceding outbreaks of fatal feline infectious peritonitis (FIP). FCoV exhibits 2 biotypes: the pathogenic disease and a benign infection with feline enteric coronavirus (FECV). Uncertainty remains regarding whether genetically distinctive avirulent and virulent forms coexist or whether an avirulent form mutates in vivo, causing FIP. To resolve these alternative hypotheses, we isolated viral sequences from FCoV-infected clinically healthy and sick cats (8 FIP cases and 48 FECV-asymptomatic animals); 735 sequences from 4 gene segments were generated and subjected to phylogenetic analyses. Viral sequences from healthy cats were distinct from sick cats on the basis of genetic distances observed in the membrane and nonstructural protein 7b genes. These data demonstrate distinctive circulating virulent and avirulent strains in natural populations. In addition, 5 membrane protein amino acid residues with functional potential differentiated healthy cats from cats with FIP. These findings may have potential as diagnostic markers for virulent FIP-associated FCoV.
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Affiliation(s)
- Meredith A Brown
- Laboratory of Genomic Diversity, National Cancer Institute, Frederick, Maryland 21702, USA.
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Diaz JV, Poma R. Diagnosis and clinical signs of feline infectious peritonitis in the central nervous system. THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 2009; 50:1091-1093. [PMID: 20046611 PMCID: PMC2748294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Affiliation(s)
- José V Diaz
- Department of Clinical Studies, University of Guelph, Ontario
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Pedersen NC, Liu H, Dodd KA, Pesavento PA. Significance of coronavirus mutants in feces and diseased tissues of cats suffering from feline infectious peritonitis. Viruses 2009; 1:166-84. [PMID: 21994544 PMCID: PMC3185486 DOI: 10.3390/v1020166] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 08/10/2009] [Accepted: 08/11/2009] [Indexed: 12/30/2022] Open
Abstract
The internal FECV→FIPV mutation theory and three of its correlates were tested in four sibs/half-sib kittens, a healthy contact cat, and in four unrelated cats that died of FIP at geographically disparate regions. Coronavirus from feces and extraintestinal FIP lesions from the same cat were always >99% related in accessory and structural gene sequences. SNPs and deletions causing a truncation of the 3c gene product were found in almost all isolates from the diseased tissues of the eight cats suffering from FIP, whereas most, but not all fecal isolates from these same cats had intact 3c genes. Other accessory and structural genes appeared normal in both fecal and lesional viruses. Deliterious mutations in the 3c gene were unique to each cat, indicating that they did not originate in one cat and were subsequently passed horizontally to the others. Compartmentalization of the parental and mutant forms was not absolute; virus of lesional type was sometimes found in feces of affected cats and virus identical to fecal type was occasionally identified in diseased tissues. Although 3c gene mutants in this study were not horizontally transmitted, the parental fecal virus was readily transmitted by contact from a cat that died of FIP to its housemate. There was a high rate of mutability in all structural and accessory genes both within and between cats, leading to minor genetic variants. More than one variant could be identified in both diseased tissues and feces of the same cat. Laboratory cats inoculated with a mixture of two closely related variants from the same FIP cat developed disease from one or the other variant, but not both. Significant genetic drift existed between isolates from geographically distinct regions of the Western US.
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Affiliation(s)
- Niels C. Pedersen
- Center for Companion Animal Health, School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA, 95616, USA; E-mail: (H.L.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-530-752-7402; Fax: +1-530-752-7701
| | - Hongwei Liu
- Center for Companion Animal Health, School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA, 95616, USA; E-mail: (H.L.)
| | - Kimberly A. Dodd
- School of Veterinary Medicine, University of California, One Shields Avenue, Davis, CA, 95616, USA; E-Mail: (K.A.D.)
| | - Patricia A. Pesavento
- Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA, 95616, USA; E-Mail: (P.A.P.)
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Addie D, Belák S, Boucraut-Baralon C, Egberink H, Frymus T, Gruffydd-Jones T, Hartmann K, Hosie MJ, Lloret A, Lutz H, Marsilio F, Pennisi MG, Radford AD, Thiry E, Truyen U, Horzinek MC. Feline infectious peritonitis. ABCD guidelines on prevention and management. J Feline Med Surg 2009; 11:594-604. [PMID: 19481039 PMCID: PMC7129471 DOI: 10.1016/j.jfms.2009.05.008] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
OVERVIEW Feline coronavirus infection is ubiquitous in domestic cats, and is particularly common where conditions are crowded. While most FCoV-infected cats are healthy or display only a mild enteritis, some go on to develop feline infectious peritonitis, a disease that is especially common in young cats and multi-cat environments. Up to 12% of FCoV-infected cats may succumb to FIP, with stress predisposing to the development of disease. DISEASE SIGNS The 'wet' or effusive form, characterised by polyserositis (abdominal and/or thoracic effusion) and vasculitis, and the 'dry' or non-effusive form (pyogranulomatous lesions in organs) reflect clinical extremes of a continuum. The clinical picture of FIP is highly variable, depending on the distribution of the vasculitis and pyogranulomatous lesions. Fever refractory to antibiotics, lethargy, anorexia and weight loss are common non-specific signs. Ascites is the most obvious manifestation of the effusive form. DIAGNOSIS The aetiological diagnosis of FIP ante-mortem may be difficult, if not impossible. The background of the cat, its history, the clinical signs, laboratory changes, antibody titres and effusion analysis should all be used to help in decision-making about further diagnostic procedures. At the time of writing, there is no non-invasive confirmatory test available for cats without effusion. DISEASE MANAGEMENT In most cases FIP is fatal. Supportive treatment is aimed at suppressing the inflammatory and detrimental immune response. However, there are no controlled studies to prove any beneficial effect of corticosteroids. VACCINATION RECOMMENDATIONS At present, only one (intranasal) FIP vaccine is available, which is considered as being non-core. Kittens may profit from vaccination when they have not been exposed to FCoV (eg, in an early-weaning programme), particularly if they enter a FCoV-endemic environment.
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Affiliation(s)
- Diane Addie
- European Advisory Board on Cat Diseases (ABCD).
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31
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Affiliation(s)
- Niels C Pedersen
- Department of Medicine and Epidemiology and Center for Companion Animal Health, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Genetic diversity and phylogenetic analysis of Feline Coronavirus sequences from Portugal. Vet Microbiol 2009; 138:163-8. [PMID: 19342183 PMCID: PMC7117414 DOI: 10.1016/j.vetmic.2009.03.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Revised: 02/16/2009] [Accepted: 03/02/2009] [Indexed: 11/23/2022]
Abstract
The distribution of FCoV Types I and II in a Portuguese cat population was studied by a RT-PCR assay targeting the 3′-end of the viral RNA. For a period of 3 years, 120 samples were collected and 57 were found positive for FCoV RNA. Within the positive samples the presence of FCoV Type I was found in 79%. Type II was only detected in 3.5% in animals with Feline Infectious Peritonitis. The remaining 17.5% could not be differentiated. These viral sequences, comprising a region within gene S were further subjected to a heteroduplex mobility assay (HMA) detecting the presence of viral quasispecies in 17% of the samples. Phylogenetic analysis for FCoV Type I revealed high genetic diversity between the Portuguese sequences and other previously characterized strains, while Type II tree showed a higher genetic homogeneity. This study confirmed the presence of FCoV Types I and II circulating in Portugal and detected high genetic diversity between circulating strains suggesting that the virus persists within the host as mixed viral populations.
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Lin CN, Su BL, Huang HP, Lee JJ, Hsieh MW, Chueh LL. Field strain feline coronaviruses with small deletions in ORF7b associated with both enteric infection and feline infectious peritonitis. J Feline Med Surg 2008; 11:413-9. [PMID: 19013091 PMCID: PMC7129072 DOI: 10.1016/j.jfms.2008.09.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2008] [Indexed: 11/02/2022]
Abstract
Feline coronavirus (FCoV) varies greatly from causing subclinical or mild enteric infections to fatal feline infectious peritonitis (FIP). The open reading frame (ORF) 7b of FCoV has been speculated to play a determining role in virulence as deletions were found to be associated with avirulent viruses. To further clarify the correlation between this gene and FIP, clinical samples from 20 cats that had succumbed to wet-type FIP and 20 clinically healthy FCoV-infected cats were analysed. The ORF7b from the peritoneal/pleural effusions of FIP cats and from the rectal swabs of healthy cats was amplified. Of the 40 FCoVs analysed, 32 were found to have an intact 7b gene whereas eight showed deletions of either three or 12 nucleotides. Surprisingly, among the eight viruses with deletions, three were from FIP diseased cats. These results show that deletions in the ORF7b gene are not constrained to low pathogenicity/enteric biotypes but also associated with pathogenicity/FIP biotypes of FCoV.
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Affiliation(s)
- Chao-Nan Lin
- Department of Veterinary Medicine, Graduate Institute of Veterinary Medicine, National Taiwan University, Taiwan
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Lorusso A, Decaro N, Schellen P, Rottier PJM, Buonavoglia C, Haijema BJ, de Groot RJ. Gain, preservation, and loss of a group 1a coronavirus accessory glycoprotein. J Virol 2008; 82:10312-7. [PMID: 18667517 PMCID: PMC2566247 DOI: 10.1128/jvi.01031-08] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Accepted: 07/21/2008] [Indexed: 12/24/2022] Open
Abstract
Coronaviruses are positive-strand RNA viruses of extraordinary genetic complexity and diversity. In addition to a common set of genes for replicase and structural proteins, each coronavirus may carry multiple group-specific genes apparently acquired through relatively recent heterologous recombination events. Here we describe an accessory gene, ORF3, unique to canine coronavirus type I (CCoV-I) and characterize its product, glycoprotein gp3. Whereas ORF3 is conserved in CCoV-I, only remnants remain in CCoV-II and CCoV-II-derived porcine and feline coronaviruses. Our findings provide insight into the evolutionary history of coronavirus group 1a and into the dynamics of gain and loss of accessory genes.
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Affiliation(s)
- Alessio Lorusso
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
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