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Jang G, Min KC, Lee IH, Won H, Yoon IJ, Kang SC, Lee C. Deletion of pentad residues in the N-terminal domain of spike protein attenuates porcine epidemic diarrhea virus in piglets. Vet Microbiol 2023; 280:109727. [PMID: 36958068 DOI: 10.1016/j.vetmic.2023.109727] [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: 01/30/2023] [Revised: 03/16/2023] [Accepted: 03/18/2023] [Indexed: 03/25/2023]
Abstract
Our previous study revealed that tissue culture-adapted porcine epidemic diarrhea virus (PEDV) strains, namely KNU-141112-S DEL2/ORF3 and -S DEL5/ORF3, were attenuated to different extents in vivo, suggesting that their independent deletion (DEL) signatures, including 2-amino acid (aa; residues 56-57) or 5-aa (residues 56-60) DEL in the N-terminal domain (NTD) of the spike (S) protein, may contribute to the reduced virulence of each strain. To investigate whether each DEL in the NTD of the S1 subunit is a determinant for the virulence of PEDV, we generated two mutant viruses, named icS DEL2 and icS DEL5, by introducing the identical double or quintuple aa DEL into S1 using reverse genetics with an infectious cDNA clone of KNU-141112 (icKNU-141112). We then orally inoculated conventional suckling piglets with icKNU-141112, icS DEL2, or icS DEL5 to compare their pathogenicities. The virulence of both DEL mutant viruses was significantly diminished compared to that of icKNU-141112, which causes severe clinical signs and 100 % mortality. Interestingly, the degree of attenuation differed between the two mutant viruses: icS DEL5 caused neither diarrhea nor mortality, whereas icS DEL2 caused mild to moderate diarrhea, higher viral titers in feces and intestinal tissues, and 25 % mortality. Furthermore, the icS DEL5-infected piglets displayed no remarkable macroscopic and microscopic intestinal lesions, while the icS DEL2-infected piglets showed histopathological changes in small intestine tissues, including moderate-to-severe villous atrophy. Our data indicate that the loss of the pentad (56GENQG60) residues in S alone can be sufficient to give rise to an attenuated phenotype of PEDV.
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Affiliation(s)
- Guehwan Jang
- College of Veterinary Medicine and Virus Vaccine Research Center, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Kyeng-Cheol Min
- ChoongAng Vaccine Laboratories, Daejeon 34055, Republic of Korea
| | - Inn Hong Lee
- ChoongAng Vaccine Laboratories, Daejeon 34055, Republic of Korea
| | - Hokeun Won
- ChoongAng Vaccine Laboratories, Daejeon 34055, Republic of Korea
| | - In-Joong Yoon
- ChoongAng Vaccine Laboratories, Daejeon 34055, Republic of Korea
| | | | - Changhee Lee
- College of Veterinary Medicine and Virus Vaccine Research Center, Gyeongsang National University, Jinju 52828, Republic of Korea.
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Chen Y, Zhang Y, Wang X, Zhou J, Ma L, Li J, Yang L, Ouyang H, Yuan H, Pang D. Transmissible Gastroenteritis Virus: An Update Review and Perspective. Viruses 2023; 15:v15020359. [PMID: 36851573 PMCID: PMC9958687 DOI: 10.3390/v15020359] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/18/2023] [Accepted: 01/24/2023] [Indexed: 01/29/2023] Open
Abstract
Transmissible gastroenteritis virus (TGEV) is a member of the alphacoronavirus genus, which has caused huge threats and losses to pig husbandry with a 100% mortality in infected piglets. TGEV is observed to be recombining and evolving unstoppably in recent years, with some of these recombinant strains spreading across species, which makes the detection and prevention of TGEV more complex. This paper reviews and discusses the basic biological properties of TGEV, factors affecting virulence, viral receptors, and the latest research advances in TGEV infection-induced apoptosis and autophagy to improve understanding of the current status of TGEV and related research processes. We also highlight a possible risk of TGEV being zoonotic, which could be evidenced by the detection of CCoV-HuPn-2018 in humans.
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Affiliation(s)
- Yiwu Chen
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Yuanzhu Zhang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Xi Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Jian Zhou
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Lerong Ma
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Jianing Li
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Lin Yang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
| | - Hongsheng Ouyang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
- Chongqing Research Institute, Jilin University, Chongqing 401120, China
- Chongqing Jitang Biotechnology Research Institute Co., Ltd., Chongqing 401120, China
| | - Hongming Yuan
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
- Chongqing Research Institute, Jilin University, Chongqing 401120, China
- Correspondence: (H.Y.); (D.P.); Tel.: +86-431-8783-6175 (D.P.)
| | - Daxin Pang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Animal Sciences, Jilin University, Changchun 130062, China
- Chongqing Research Institute, Jilin University, Chongqing 401120, China
- Chongqing Jitang Biotechnology Research Institute Co., Ltd., Chongqing 401120, China
- Correspondence: (H.Y.); (D.P.); Tel.: +86-431-8783-6175 (D.P.)
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Yan Q, Liu X, Sun Y, Zeng W, Li Y, Zhao F, Wu K, Fan S, Zhao M, Chen J, Yi L. Swine Enteric Coronavirus: Diverse Pathogen–Host Interactions. Int J Mol Sci 2022; 23:ijms23073953. [PMID: 35409315 PMCID: PMC8999375 DOI: 10.3390/ijms23073953] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 12/23/2022] Open
Abstract
Swine enteric coronavirus (SeCoV) causes acute gastroenteritis and high mortality in newborn piglets. Since the last century, porcine transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PEDV) have swept farms all over the world and caused substantial economic losses. In recent years, porcine delta coronavirus (PDCoV) and swine acute diarrhea syndrome coronavirus (SADS-CoV) have been emerging SeCoVs. Some of them even spread across species, which made the epidemic situation of SeCoV more complex and changeable. Recent studies have begun to reveal the complex SeCoV–host interaction mechanism in detail. This review summarizes the current advances in autophagy, apoptosis, and innate immunity induced by SeCoV infection. These complex interactions may be directly involved in viral replication or the alteration of some signal pathways.
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Affiliation(s)
- Quanhui Yan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Xiaodi Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Yawei Sun
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Weijun Zeng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Yuwan Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Feifan Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Keke Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Shuangqi Fan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Mingqiu Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
| | - Jinding Chen
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Correspondence: (J.C.); (L.Y.); Tel.: +86-20-8528-8017 (J.C. & L.Y.)
| | - Lin Yi
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China; (Q.Y.); (X.L.); (Y.S.); (W.Z.); (Y.L.); (F.Z.); (K.W.); (S.F.); (M.Z.)
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
- Key Laboratory of Zoonosis Prevention and Control of Guangdong Province, Guangzhou 510642, China
- Correspondence: (J.C.); (L.Y.); Tel.: +86-20-8528-8017 (J.C. & L.Y.)
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Song L, Chen J, Hao P, Jiang Y, Xu W, Li L, Chen S, Gao Z, Jin N, Ren L, Li C. Differential Transcriptomics Analysis of IPEC-J2 Cells Single or Coinfected With Porcine Epidemic Diarrhea Virus and Transmissible Gastroenteritis Virus. Front Immunol 2022; 13:844657. [PMID: 35401515 PMCID: PMC8989846 DOI: 10.3389/fimmu.2022.844657] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/28/2022] [Indexed: 12/14/2022] Open
Abstract
Porcine epidemic diarrhea (PED) and transmissible gastroenteritis (TGE) caused by porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV) are two highly contagious intestinal diseases in the swine industry worldwide. Notably, coinfection of TGEV and PEDV is common in piglets with diarrhea-related diseases. In this study, intestinal porcine epithelial cells (IPEC-J2) were single or coinfected with PEDV and/or TGEV, followed by the comparison of differentially expressed genes (DEGs), especially interferon-stimulated genes (ISGs), between different groups via transcriptomics analysis and real-time qPCR. The antiviral activity of swine interferon-induced transmembrane protein 3 (sIFITM3) on PEDV and TGEV infection was also evaluated. The results showed that DEGs can be detected in the cells infected with PEDV, TGEV, and PEDV+TGEV at 12, 24, and 48 hpi, and the number of DEGs was the highest at 24 hpi. The DEGs are mainly annotated to the GO terms of protein binding, immune system process, organelle part, and intracellular organelle part. Furthermore, 90 ISGs were upregulated during PEDV or TGEV infection, 27 of which were associated with antiviral activity, including ISG15, OASL, IFITM1, and IFITM3. Furthermore, sIFITM3 can significantly inhibit PEDV and TGEV infection in porcine IPEC-J2 cells and/or monkey Vero cells. Besides, sIFITM3 can also inhibit vesicular stomatitis virus (VSV) replication in Vero cells. These results indicate that sIFITM3 has broad-spectrum antiviral activity.
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Affiliation(s)
- Lina Song
- College of Veterinary Medicine, Key Lab for Zoonoses Research, Ministry of Education, Jilin University, Changchun, China
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Jing Chen
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Pengfei Hao
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Yuhang Jiang
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Wang Xu
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Letian Li
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Si Chen
- College of Animal Sciences, Jilin University, Changchun, China
| | - Zihan Gao
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Ningyi Jin
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Linzhu Ren
- College of Animal Sciences, Jilin University, Changchun, China
| | - Chang Li
- Research Unit of Key Technologies for Prevention and Control of Virus Zoonoses, Chinese Academy of Medical Sciences, Changchun Institute of Veterinary Medicine, Chinese Academy of Agricultural Sciences, Changchun, China
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5
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Hardison RL, Nelson SW, Barriga D, Ghere JM, Fenton GA, James RR, Stewart MJ, Lee SD, Calfee MW, Ryan SP, Howard MW. Efficacy of detergent-based cleaning methods against coronavirus MHV-A59 on porous and non-porous surfaces. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2022; 19:91-101. [PMID: 34878351 PMCID: PMC8965596 DOI: 10.1080/15459624.2021.2015075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
This study evaluated the efficacy of detergent-based surface cleaning methods against Murine Hepatitis Virus A59 (MHV) as a surrogate coronavirus for SARS-CoV-2. MHV (5% soil load in culture medium or simulated saliva) was inoculated onto four different high-touch materials [stainless steel (SS), Acrylonitrile Butadiene Styrene plastic (ABS), Formica, seat fabric (SF)]. Immediately and 2-hr post-inoculation, coupons were cleaned (damp wipe wiping) with and without pretreatment with detergent solution or 375 ppm hard water. Results identified that physical removal (no pretreatment) removed >2.3 log10 MHV on ABS, SS, and Formica when surfaces were cleaned immediately. Pretreatment with detergent or hard water increased effectiveness over wet wiping 2-hr post-inoculation; pretreatment with detergent significantly increased (p ≤ 0.05) removal of MHV in simulated saliva, but not in culture media, over hard water pretreatment (Formica and ABS). Detergent and hard water cleaning methods were ineffective on SF under all conditions. Overall, efficacy of cleaning methods against coronaviruses are material- and matrix-dependent; pre-wetting surfaces with detergent solutions increased efficacy against coronavirus suspended in simulated saliva. This study provides data highlighting the importance of incorporating a pre-wetting step prior to detergent cleaning and can inform cleaning strategies to reducing coronavirus surface transmission.
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Affiliation(s)
| | | | | | | | | | | | | | - Sang Don Lee
- U.S. Environmental Protection Agency, Durham, North Carolina
| | - M. Worth Calfee
- U.S. Environmental Protection Agency, Durham, North Carolina
| | - Shawn P. Ryan
- U.S. Environmental Protection Agency, Durham, North Carolina
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6
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Bruland T, Østvik AE, Sandvik AK, Hansen MD. Host-Viral Interactions in the Pathogenesis of Ulcerative Colitis. Int J Mol Sci 2021; 22:ijms221910851. [PMID: 34639191 PMCID: PMC8509287 DOI: 10.3390/ijms221910851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/04/2021] [Accepted: 10/05/2021] [Indexed: 12/12/2022] Open
Abstract
Ulcerative colitis is characterized by relapsing and remitting colonic mucosal inflammation. During the early stages of viral infection, innate immune defenses are activated, leading to the rapid release of cytokines and the subsequent initiation of downstream responses including inflammation. Previously, intestinal viruses were thought to be either detrimental or neutral to the host. However, persisting viruses may have a role as resident commensals and confer protective immunity during inflammation. On the other hand, the dysregulation of gut mucosal immune responses to viruses can trigger excessive, pathogenic inflammation. The purpose of this review is to discuss virus-induced innate immune responses that are at play in ulcerative colitis.
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Affiliation(s)
- Torunn Bruland
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7491 Trondheim, Norway; (T.B.); (A.E.Ø.); (A.K.S.)
- Department of Gastroenterology and Hepatology, Clinic of Medicine, St. Olav’s University Hospital, 7030 Trondheim, Norway
| | - Ann Elisabet Østvik
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7491 Trondheim, Norway; (T.B.); (A.E.Ø.); (A.K.S.)
- Department of Gastroenterology and Hepatology, Clinic of Medicine, St. Olav’s University Hospital, 7030 Trondheim, Norway
| | - Arne Kristian Sandvik
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7491 Trondheim, Norway; (T.B.); (A.E.Ø.); (A.K.S.)
- Department of Gastroenterology and Hepatology, Clinic of Medicine, St. Olav’s University Hospital, 7030 Trondheim, Norway
- Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Marianne Doré Hansen
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7491 Trondheim, Norway; (T.B.); (A.E.Ø.); (A.K.S.)
- Department of Medical Microbiology, Clinic of Laboratory Medicine, St. Olav’s University Hospital, 7030 Trondheim, Norway
- Correspondence:
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7
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Cell Entry of Animal Coronaviruses. Viruses 2021; 13:v13101977. [PMID: 34696406 PMCID: PMC8540712 DOI: 10.3390/v13101977] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 01/11/2023] Open
Abstract
Coronaviruses (CoVs) are a group of enveloped positive-sense RNA viruses and can cause deadly diseases in animals and humans. Cell entry is the first and essential step of successful virus infection and can be divided into two ongoing steps: cell binding and membrane fusion. Over the past two decades, stimulated by the global outbreak of SARS-CoV and pandemic of SARS-CoV-2, numerous efforts have been made in the CoV research. As a result, significant progress has been achieved in our understanding of the cell entry process. Here, we review the current knowledge of this essential process, including the viral and host components involved in cell binding and membrane fusion, molecular mechanisms of their interactions, and the sites of virus entry. We highlight the recent findings of host restriction factors that inhibit CoVs entry. This knowledge not only enhances our understanding of the cell entry process, pathogenesis, tissue tropism, host range, and interspecies-transmission of CoVs but also provides a theoretical basis to design effective preventive and therapeutic strategies to control CoVs infection.
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8
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The roles of two major domains of the porcine deltacoronavirus spike subunit 1 in receptor binding and neutralization. J Virol 2021; 95:e0111821. [PMID: 34549985 PMCID: PMC8610578 DOI: 10.1128/jvi.01118-21] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Determination of the mechanisms of interspecies transmission is of great significance for the prevention of epidemic diseases caused by emerging coronaviruses (CoVs). Recently, porcine deltacoronavirus (PDCoV) was shown to exhibit broad host cell range mediated by surface expression of aminopeptidase N (APN), and humans have been reported to be at risk of PDCoV infection. In the present study, we first demonstrated overexpression of APN orthologues from various species, including mice and felines, in the APN-deficient swine small intestine epithelial cells permitted PDCoV infection, confirming that APN broadly facilitates PDCoV cellular entry and perhaps subsequent interspecies transmission. PDCoV was able to limitedly infect mice in vivo, distributing mainly in enteric and lymphoid tissues, suggesting that mice may serve as a susceptible reservoir of PDCoV. Furthermore, elements (two glycosylation sites and four aromatic amino acids) on the surface of domain B (S1B) of the PDCoV spike glycoprotein S1 subunit were identified to be critical for cellular surface binding of APN orthologues. However, both domain A (S1A) and domain B (S1B) were able to elicit potent neutralizing antibodies against PDCoV infection. The antibodies against S1A inhibited the hemagglutination activity of PDCoV using erythrocytes from various species, which might account for the neutralizing capacity of S1A antibodies partially through a blockage of sialic acid binding. The study reveals the tremendous potential of PDCoV for interspecies transmission and the role of two major PDCoV S1 domains in receptor binding and neutralization, providing a theoretical basis for development of intervention strategies. IMPORTANCE Coronaviruses exhibit a tendency for recombination and mutation, which enables them to quickly adapt to various novel hosts. Previously, orthologues of aminopeptidase N (APN) from mammalian and avian species were found to be associated with porcine deltacoronavirus (PDCoV) cellular entry in vitro. Here, we provide in vivo evidence that mice are susceptible to PDCoV limited infection. We also show that two major domains (S1A and S1B) of the PDCoV spike glycoprotein involved in APN receptor binding can elicit neutralizing antibodies, identifying two glycosylation sites and four aromatic amino acids on the surface of the S1B domain critical for APN binding and demonstrating that the neutralization activity of S1A antibodies is partially attributed to blockage of sugar binding activity. Our findings further implicate PDCoV’s great potential for interspecies transmission, and the data of receptor binding and neutralization may provide a basis for development of future intervention strategies.
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Millet JK, Jaimes JA, Whittaker GR. Molecular diversity of coronavirus host cell entry receptors. FEMS Microbiol Rev 2021; 45:fuaa057. [PMID: 33118022 PMCID: PMC7665467 DOI: 10.1093/femsre/fuaa057] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 10/24/2020] [Indexed: 12/11/2022] Open
Abstract
Coronaviruses are a group of viruses causing disease in a wide range of animals, and humans. Since 2002, the successive emergence of bat-borne severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), swine acute diarrhea syndrome coronavirus (SADS-CoV) and SARS-CoV-2 has reinforced efforts in uncovering the molecular and evolutionary mechanisms governing coronavirus cell tropism and interspecies transmission. Decades of studies have led to the discovery of a broad set of carbohydrate and protein receptors for many animal and human coronaviruses. As the main determinant of coronavirus entry, the spike protein binds to these receptors and mediates membrane fusion. Prone to mutations and recombination, spike evolution has been studied extensively. The interactions between spike proteins and their receptors are often complex and despite many advances in the field, there remains many unresolved questions concerning coronavirus tropism modification and cross-species transmission, potentially leading to delays in outbreak responses. The emergence of SARS-CoV-2 underscores the need to address these outstanding issues in order to better anticipate new outbreaks. In this review, we discuss the latest advances in the field of coronavirus receptors emphasizing on the molecular and evolutionary processes that underlie coronavirus receptor usage and host range expansion.
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Affiliation(s)
- Jean K Millet
- Université Paris-Saclay, INRAE, UVSQ, Virologie et Immunologie Moléculaires, 78352 Jouy-en-Josas, France
| | - Javier A Jaimes
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Gary R Whittaker
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
- Master of Public Health Program, Cornell University, Ithaca, NY 14853, USA
- Cornell Feline Health Center, Ithaca, NY 14853, USA
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10
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Cortez V, Schultz-Cherry S. The role of goblet cells in viral pathogenesis. FEBS J 2021; 288:7060-7072. [PMID: 33507606 PMCID: PMC8013445 DOI: 10.1111/febs.15731] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 12/19/2022]
Abstract
Goblet cells are specialized epithelial cells that are essential to the formation of the mucus barriers in the airways and intestines. Armed with an arsenal of defenses, goblet cells can rapidly respond to infection but must balance this response with maintaining homeostasis. Whereas goblet cell defenses against bacterial and parasitic infections have been characterized, we are just beginning to understand their responses to viral infections. Here, we outline what is known about the enteric and respiratory viruses that target goblet cells, the direct and bystander effects caused by viral infection and how viral interactions with the mucus barrier can alter the course of infection. Together, these factors can play a significant role in driving viral pathogenesis and disease outcomes.
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Affiliation(s)
- Valerie Cortez
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Stacey Schultz-Cherry
- Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, TN, USA
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11
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Porcine enteric coronaviruses: an updated overview of the pathogenesis, prevalence, and diagnosis. Vet Res Commun 2021; 45:75-86. [PMID: 34251560 PMCID: PMC8273569 DOI: 10.1007/s11259-021-09808-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 06/22/2021] [Indexed: 02/07/2023]
Abstract
The recent prevalence of coronavirus (CoV) poses a serious threat to animal and human health. Currently, porcine enteric coronaviruses (PECs), including the transmissible gastroenteritis virus (TGEV), the novel emerging swine acute diarrhoea syndrome coronavirus (SADS-CoV), porcine delta coronavirus (PDCoV), and re-emerging porcine epidemic diarrhoea virus (PEDV), which infect pigs of different ages, have caused more frequent occurrences of diarrhoea, vomiting, and dehydration with high morbidity and mortality in piglets. PECs have the potential for cross-species transmission and are causing huge economic losses in the pig industry in China and the world, which therefore needs to be urgently addressed. Accordingly, this article summarises the pathogenicity, prevalence, and diagnostic methods of PECs and provides an important reference for their improved diagnosis, prevention, and control.
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12
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Zhang Q, Chen CZ, Swaroop M, Xu M, Wang L, Lee J, Wang AQ, Pradhan M, Hagen N, Chen L, Shen M, Luo Z, Xu X, Xu Y, Huang W, Zheng W, Ye Y. Heparan sulfate assists SARS-CoV-2 in cell entry and can be targeted by approved drugs in vitro. Cell Discov 2020; 6:80. [PMID: 33298900 PMCID: PMC7610239 DOI: 10.1038/s41421-020-00222-5] [Citation(s) in RCA: 141] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 09/28/2020] [Indexed: 12/24/2022] Open
Abstract
The cell entry of SARS-CoV-2 has emerged as an attractive drug repurposing target for COVID-19. Here we combine genetics and chemical perturbation to demonstrate that ACE2-mediated entry of SARS-Cov and CoV-2 requires the cell surface heparan sulfate (HS) as an assisting cofactor: ablation of genes involved in HS biosynthesis or incubating cells with a HS mimetic both inhibit Spike-mediated viral entry. We show that heparin/HS binds to Spike directly, and facilitates the attachment of Spike-bearing viral particles to the cell surface to promote viral entry. We screened approved drugs and identified two classes of inhibitors that act via distinct mechanisms to target this entry pathway. Among the drugs characterized, Mitoxantrone is a potent HS inhibitor, while Sunitinib and BNTX disrupt the actin network to indirectly abrogate HS-assisted viral entry. We further show that drugs of the two classes can be combined to generate a synergized activity against SARS-CoV-2-induced cytopathic effect. Altogether, our study establishes HS as an attachment factor that assists SARS coronavirus cell entry and reveals drugs capable of targeting this important step in the viral life cycle.
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Affiliation(s)
- Qi Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Catherine Zhengzheng Chen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Manju Swaroop
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Miao Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Lihui Wang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Juhyung Lee
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Amy Qiu Wang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Manisha Pradhan
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Natalie Hagen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Lu Chen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Zhiji Luo
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Xin Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Yue Xu
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Wenwei Huang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Wei Zheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD, 20850, USA
| | - Yihong Ye
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.
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Engin AB, Engin ED, Engin A. Dual function of sialic acid in gastrointestinal SARS-CoV-2 infection. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2020; 79:103436. [PMID: 32562764 PMCID: PMC7833001 DOI: 10.1016/j.etap.2020.103436] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 05/11/2023]
Abstract
Recent analysis concerning the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)- angiotensin converting enzyme (ACE) receptor interaction in enterocytes, the definition of gut-lung axis, as well as the molecular basis of sialic acid-related dual recognition concept in gastrointestinal SARS-CoV-2 infection, have brought a new perspective to potential therapeutic targets. In this review evolving research and clinical data on gastrointestinal SARS-CoV-2 infection are discussed in the context of viral fusion and entry mechanisms, focusing on the different triggers used by coronaviruses. Furthermore, it is emphasized that the viral spike protein is prevented from binding gangliosides, which are composed of a glycosphingolipid with one or more sialic acids, in the presence of chloroquine or hydroxychloroquine. In gastrointestinal SARS-CoV-2 infection the efficiency of these repositioned drugs is debated.
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Affiliation(s)
- Ayse Basak Engin
- Gazi University, Faculty of Pharmacy, Department of Toxicology, Ankara, Turkey.
| | - Evren Doruk Engin
- Ankara University, Biotechnology Institute, Gumusdere Campus, Kecioren, Ankara, Turkey
| | - Atilla Engin
- Gazi University, Faculty of Medicine, Department of General Surgery, Ankara, Turkey
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14
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Zhang Q, Chen CZ, Swaroop M, Xu M, Wang L, Lee J, Wang AQ, Pradhan M, Hagen N, Chen L, Shen M, Luo Z, Xu X, Xu Y, Huang W, Zheng W, Ye Y. Heparan sulfate assists SARS-CoV-2 in cell entry and can be targeted by approved drugs in vitro. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.07.14.202549. [PMID: 32699847 PMCID: PMC7373127 DOI: 10.1101/2020.07.14.202549] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The cell entry of SARS-CoV-2 has emerged as an attractive drug repurposing target for COVID-19. Here we combine genetics and chemical perturbation to demonstrate that ACE2-mediated entry of SARS-CoV and CoV-2 requires the cell surface heparan sulfate (HS) as an assisting cofactor: ablation of genes involved in HS biosynthesis or incubating cells with a HS mimetic both inhibit Spike-mediated viral entry. We show that heparin/HS binds to Spike directly, facilitates the attachment of viral particles to the cell surface to promote cell entry. We screened approved drugs and identified two classes of inhibitors that act via distinct mechanisms to target this entry pathway. Among the drugs characterized, Mitoxantrone is a potent HS inhibitor, while Sunitinib and BNTX disrupt the actin network to indirectly abrogate HS-assisted viral entry. We further show that drugs of the two classes can be combined to generate a synergized activity against SARS-CoV-2-induced cytopathic effect. Altogether, our study establishes HS as an attachment factor that assists SARS coronavirus cell entry, and reveals drugs capable of targeting this important step in the viral life cycle.
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Affiliation(s)
- Qi Zhang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Catherine Z. Chen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Manju Swaroop
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Miao Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Lihui Wang
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Juhyung Lee
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Amy Q. Wang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Manisha Pradhan
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Natalie Hagen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Lu Chen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Min Shen
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Zhiji Luo
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Xin Xu
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Yue Xu
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Wenwei Huang
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Wei Zheng
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850
| | - Yihong Ye
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
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15
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SARS-CoV-2 Evolutionary Adaptation toward Host Entry and Recognition of Receptor O-Acetyl Sialylation in Virus-Host Interaction. Int J Mol Sci 2020; 21:ijms21124549. [PMID: 32604730 PMCID: PMC7352545 DOI: 10.3390/ijms21124549] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/15/2020] [Accepted: 06/22/2020] [Indexed: 02/06/2023] Open
Abstract
The recently emerged SARS-CoV-2 is the cause of the global health crisis of the coronavirus disease 2019 (COVID-19) pandemic. No evidence is yet available for CoV infection into hosts upon zoonotic disease outbreak, although the CoV epidemy resembles influenza viruses, which use sialic acid (SA). Currently, information on SARS-CoV-2 and its receptors is limited. O-acetylated SAs interact with the lectin-like spike glycoprotein of SARS CoV-2 for the initial attachment of viruses to enter into the host cells. SARS-CoV-2 hemagglutinin-esterase (HE) acts as the classical glycan-binding lectin and receptor-degrading enzyme. Most β-CoVs recognize 9-O-acetyl-SAs but switched to recognizing the 4-O-acetyl-SA form during evolution of CoVs. Type I HE is specific for the 9-O-Ac-SAs and type II HE is specific for 4-O-Ac-SAs. The SA-binding shift proceeds through quasi-synchronous adaptations of the SA-recognition sites of the lectin and esterase domains. The molecular switching of HE acquisition of 4-O-acetyl binding from 9-O-acetyl SA binding is caused by protein–carbohydrate interaction (PCI) or lectin–carbohydrate interaction (LCI). The HE gene was transmitted to a β-CoV lineage A progenitor by horizontal gene transfer from a 9-O-Ac-SA–specific HEF, as in influenza virus C/D. HE acquisition, and expansion takes place by cross-species transmission over HE evolution. This reflects viral evolutionary adaptation to host SA-containing glycans. Therefore, CoV HE receptor switching precedes virus evolution driven by the SA-glycan diversity of the hosts. The PCI or LCI stereochemistry potentiates the SA–ligand switch by a simple conformational shift of the lectin and esterase domains. Therefore, examination of new emerging viruses can lead to better understanding of virus evolution toward transitional host tropism. A clear example of HE gene transfer is found in the BCoV HE, which prefers 7,9-di-O-Ac-SAs, which is also known to be a target of the bovine torovirus HE. A more exciting case of such a switching event occurs in the murine CoVs, with the example of the β-CoV lineage A type binding with two different subtypes of the typical 9-O-Ac-SA (type I) and the exclusive 4-O-Ac-SA (type II) attachment factors. The protein structure data for type II HE also imply the virus switching to binding 4-O acetyl SA from 9-O acetyl SA. Principles of the protein–glycan interaction and PCI stereochemistry potentiate the SA–ligand switch via simple conformational shifts of the lectin and esterase domains. Thus, our understanding of natural adaptation can be specified to how carbohydrate/glycan-recognizing proteins/molecules contribute to virus evolution toward host tropism. Under the current circumstances where reliable antiviral therapeutics or vaccination tools are lacking, several trials are underway to examine viral agents. As expected, structural and non-structural proteins of SARS-CoV-2 are currently being targeted for viral therapeutic designation and development. However, the modern global society needs SARS-CoV-2 preventive and therapeutic drugs for infected patients. In this review, the structure and sialobiology of SARS-CoV-2 are discussed in order to encourage and activate public research on glycan-specific interaction-based drug creation in the near future.
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Abstract
Coronaviruses (CoVs) have caused outbreaks of deadly pneumonia in humans since the beginning of the 21st century. The severe acute respiratory syndrome coronavirus (SARS-CoV) emerged in 2002 and was responsible for an epidemic that spread to five continents with a fatality rate of 10% before being contained in 2003 (with additional cases reported in 2004). The Middle-East respiratory syndrome coronavirus (MERS-CoV) emerged in the Arabian Peninsula in 2012 and has caused recurrent outbreaks in humans with a fatality rate of 35%. SARS-CoV and MERS-CoV are zoonotic viruses that crossed the species barrier using bats/palm civets and dromedary camels, respectively. No specific treatments or vaccines have been approved against any of the six human coronaviruses, highlighting the need to investigate the principles governing viral entry and cross-species transmission as well as to prepare for zoonotic outbreaks which are likely to occur due to the large reservoir of CoVs found in mammals and birds. Here, we review our understanding of the infection mechanism used by coronaviruses derived from recent structural and biochemical studies.
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Affiliation(s)
- M Alejandra Tortorici
- Department of Biochemistry, University of Washington, Seattle, WA, United States; Institut Pasteur, Unité de Virologie Structurale, Paris, France; CNRS UMR 3569, Unité de Virologie Structurale, Paris, France
| | - David Veesler
- Department of Biochemistry, University of Washington, Seattle, WA, United States.
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Porcine Intestinal Enteroids: a New Model for Studying Enteric Coronavirus Porcine Epidemic Diarrhea Virus Infection and the Host Innate Response. J Virol 2019; 93:JVI.01682-18. [PMID: 30541861 PMCID: PMC6384061 DOI: 10.1128/jvi.01682-18] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 12/04/2018] [Indexed: 02/08/2023] Open
Abstract
PEDV is a highly contagious enteric coronavirus that causes significant economic losses, and the lack of a good in vitro model system is a major roadblock to an in-depth understanding of PEDV pathogenesis. Here, we generated a porcine intestinal enteroid model for PEDV infection. Utilizing porcine intestinal enteroids, we demonstrated that PEDV infects multiple lineages of the intestinal epithelium and preferably infects ileal enteroids over colonoids and that enteroids prefer to respond to IFN lambda 1 over IFN-α. These events recapitulate the events that occur in vivo. This study constitutes the first use of a primary intestinal enteroid model to investigate the susceptibility of porcine enteroids to PEDV and to determine the antiviral response following infection. Our study provides important insights into the events associated with PEDV infection of the porcine intestine and provides a valuable in vitro model for studying not only PEDV but also other swine enteric viruses. Porcine epidemic diarrhea virus (PEDV), a member of the group of alphacoronaviruses, is the pathogen of a highly contagious gastrointestinal swine disease. The elucidation of the events associated with the intestinal epithelial response to PEDV infection has been limited by the absence of good in vitro porcine intestinal models that recapitulate the multicellular complexity of the gastrointestinal tract. Here, we generated swine enteroids from the intestinal crypt stem cells of the duodenum, jejunum, or ileum and found that the generated enteroids are able to satisfactorily recapitulate the complicated intestinal epithelium in vivo and are susceptible to infection by PEDV. PEDV infected multiple types of cells, including enterocytes, stem cells, and goblet cells, and exhibited segmental infection discrepancies compared with ileal enteroids and colonoids, and this finding was verified in vivo. Moreover, the clinical isolate PEDV-JMS propagated better in ileal enteroids than the cell-adapted isolate PEDV-CV777, and PEDV infection suppressed interferon (IFN) production early during the infection course. IFN lambda elicited a potent antiviral response and inhibited PEDV in enteroids more efficiently than IFN alpha (IFN-α). Therefore, swine enteroids provide a novel in vitro model for exploring the pathogenesis of PEDV and for the in vitro study of the interplay between a host and a variety of swine enteric viruses. IMPORTANCE PEDV is a highly contagious enteric coronavirus that causes significant economic losses, and the lack of a good in vitro model system is a major roadblock to an in-depth understanding of PEDV pathogenesis. Here, we generated a porcine intestinal enteroid model for PEDV infection. Utilizing porcine intestinal enteroids, we demonstrated that PEDV infects multiple lineages of the intestinal epithelium and preferably infects ileal enteroids over colonoids and that enteroids prefer to respond to IFN lambda 1 over IFN-α. These events recapitulate the events that occur in vivo. This study constitutes the first use of a primary intestinal enteroid model to investigate the susceptibility of porcine enteroids to PEDV and to determine the antiviral response following infection. Our study provides important insights into the events associated with PEDV infection of the porcine intestine and provides a valuable in vitro model for studying not only PEDV but also other swine enteric viruses.
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Deletion of a 197-Amino-Acid Region in the N-Terminal Domain of Spike Protein Attenuates Porcine Epidemic Diarrhea Virus in Piglets. J Virol 2017; 91:JVI.00227-17. [PMID: 28490591 DOI: 10.1128/jvi.00227-17] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 04/26/2017] [Indexed: 02/06/2023] Open
Abstract
We previously isolated a porcine epidemic diarrhea virus (PEDV) strain, PC177, by blind serial passaging of the intestinal contents of a diarrheic piglet in Vero cell culture. Compared with the highly virulent U.S. PEDV strain PC21A, the tissue culture-adapted PC177 (TC-PC177) contains a 197-amino-acid (aa) deletion in the N-terminal domain of the spike (S) protein. We orally inoculated neonatal, conventional suckling piglets with TC-PC177 or PC21A to compare their pathogenicities. Within 7 days postinoculation, TC-PC177 caused mild diarrhea and lower fecal viral RNA shedding, with no mortality, whereas PC21A caused severe clinical signs and 55% mortality. To investigate whether infection with TC-PC177 can induce cross-protection against challenge with a highly virulent PEDV strain, all the surviving piglets were challenged with PC21A at 3 weeks postinoculation. Compared with 100% protection in piglets initially inoculated with PC21A, 88% and 100% TC-PC177- and mock-inoculated piglets had diarrhea following challenge, respectively, indicating incomplete cross-protection. To investigate whether this 197-aa deletion was the determinant for the attenuation of TC-PC177, we generated a mutant (icPC22A-S1Δ197) bearing the 197-aa deletion from an infectious cDNA clone of the highly virulent PEDV PC22A strain (infectious clone PC22A, icPC22A). In neonatal gnotobiotic pigs, the icPC22A-S1Δ197 virus caused mild to moderate diarrhea, lower titers of viral shedding, and no mortality, whereas the icPC22A virus caused severe diarrhea and 100% mortality. Our data indicate that deletion of this 197-aa fragment in the spike protein can attenuate a highly virulent PEDV, but the virus may lose important epitopes for inducing robust protective immunity.IMPORTANCE The emerging, highly virulent PEDV strains have caused substantial economic losses worldwide. However, the virulence determinants are not established. In this study, we found that a 197-aa deletion in the N-terminal region of the S protein did not alter virus (TC-PC177) tissue tropism but reduced the virulence of the highly virulent PEDV strain PC22A in neonatal piglets. We also demonstrated that the primary infection with TC-PC177 failed to induce complete cross-protection against challenge by the highly virulent PEDV PC21A, suggesting that the 197-aa region may contain important epitopes for inducing protective immunity. Our results provide an insight into the role of this large deletion in virus propagation and pathogenicity. In addition, the reverse genetics platform of the PC22A strain was further optimized for the rescue of recombinant PEDV viruses in vitro This breakthrough allows us to investigate other virulence determinants of PEDV strains and will provide knowledge leading to better control PEDV infections.
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Krimmling T, Beineke A, Schwegmann-Weßels C. Infection of porcine precision cut intestinal slices by transmissible gastroenteritis coronavirus demonstrates the importance of the spike protein for enterotropism of different virus strains. Vet Microbiol 2017. [PMID: 28622850 PMCID: PMC7117111 DOI: 10.1016/j.vetmic.2017.04.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Porcine precision cut intestinal slices can be used to analyze virus infection. TGEV strains differ in their ability to infect cells of the jejunal epithelium. Enterotropism of TGEV is determined by its spike protein S.
TGEV is a coronavirus that is still widely spread in pig farming. On molecular level this virus has been studied in detail. However, studying TGEV infection within the complexity of the porcine intestinal epithelium reveals difficulties due to limiting infection models. Here we established a new ex vivo model to analyze the enterotropism of TGEV in porcine intestinal tissue. Precision cut intestinal slices (PCIS) were produced and ATP level was measured to proof vitality of the slices. ATP measurements and HE staining revealed living tissue in culture for up to 24 h. PCIS were infected with three different TGEV strains. TGEV PUR 46-MAD is a commonly used TGEV strain that is known to be attenuated. TGEV Miller was passaged in piglets several times to reveal high infection. Finally, TGEV GFP is a recombinant strain that obtained its main body from TGEV PUR 46-MAD, but its spike protein from TGEV PUR-C11 that showed high mortality in piglets in vivo. Our results were in complete consensus of these statements. TGEV Miller mildly and TGEV GFP extensively infected the cells in the jejunum based on the amount of positive stained epithelial cells. However, for TGEV PUR 46-MAD no nucleocapsid protein was detected in the epithelial cells of the tissue. This shows that differences in TGEV strains and their infectious potential are highly dependent on their S protein.
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Affiliation(s)
- Tanja Krimmling
- Institute of Virology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Andreas Beineke
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Christel Schwegmann-Weßels
- Institute of Virology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany.
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Jung K, Saif LJ. Goblet cell depletion in small intestinal villous and crypt epithelium of conventional nursing and weaned pigs infected with porcine epidemic diarrhea virus. Res Vet Sci 2016; 110:12-15. [PMID: 28159230 DOI: 10.1016/j.rvsc.2016.10.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 08/26/2016] [Accepted: 10/22/2016] [Indexed: 11/28/2022]
Abstract
Intestinal goblet cells secret mucins to form mucus layers critical for maintaining the integrity of the intestinal epithelium. Porcine epidemic diarrhea virus (PEDV) causes watery diarrhea and high mortality of suckling pigs. PEDV mainly infects villous epithelial cells of the small intestine, and infected cells undergo acute, massive necrosis, followed by severe villous atrophy. Conventional 9-day-old nursing pigs [PEDV-inoculated (n=9); Mock (n=11)] and 26-day-old weaned [PEDV-inoculated (n=11); Mock (n=9)] were inoculated orally [8.9 log10 genomic equivalents/pig] with PEDV strain PC21A or mock. We used alcian blue or Periodic-Acid-Schiff staining for the detection of acidic or neutral mucin-secreting goblet cells in the small intestine. We demonstrated that PEDV infection of the nursing pigs at post-inoculation days (PIDs) 1-5 and weaned pigs at PIDs 3-5 led to depletion or significant reduction in the number of goblet cells (and also the number of villous goblet cells normalized by jejunal villous crypt height to crypt depth ratios) in the villi or crypts. These findings coincided with the development of intestinal villous atrophy. By immunohistochemistry, a few PEDV antigen-positive goblet cells were identified in the jejunal or ileal villous epithelium of the infected nursing or weaned pigs. During the early stages of PEDV infection, goblet cell mucins in the small intestine may be decreased, possibly leading to an impaired mucus layer and increased susceptibility to secondary enteric bacterial infection.
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Affiliation(s)
- Kwonil Jung
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA.
| | - Linda J Saif
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA.
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Carcinoembryonic Antigen-Related Cell Adhesion Molecule 5 Is an Important Surface Attachment Factor That Facilitates Entry of Middle East Respiratory Syndrome Coronavirus. J Virol 2016; 90:9114-27. [PMID: 27489282 DOI: 10.1128/jvi.01133-16] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 07/23/2016] [Indexed: 12/16/2022] Open
Abstract
UNLABELLED The spike proteins of coronaviruses are capable of binding to a wide range of cellular targets, which contributes to the broad species tropism of coronaviruses. Previous reports have demonstrated that Middle East respiratory syndrome coronavirus (MERS-CoV) predominantly utilizes dipeptidyl peptidase 4 (DPP4) for cell entry. However, additional cellular binding targets of the MERS-CoV spike protein that may augment MERS-CoV infection have not been further explored. In the current study, using the virus overlay protein binding assay (VOPBA), we identified carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) as a novel cell surface binding target of MERS-CoV. CEACAM5 coimmunoprecipitated with the spike protein of MERS-CoV in both overexpressed and endogenous settings. Disrupting the interaction between CEACAM5 and MERS-CoV spike with anti-CEACAM5 antibody, recombinant CEACAM5 protein, or small interfering RNA (siRNA) knockdown of CEACAM5 significantly inhibited the entry of MERS-CoV. Recombinant expression of CEACAM5 did not render nonpermissive baby hamster kidney (BHK21) cells susceptible to MERS-CoV infection. Instead, CEACAM5 overexpression significantly enhanced the attachment of MERS-CoV to the BHK21 cells. More importantly, the entry of MERS-CoV was increased when CEACAM5 was overexpressed in permissive cells, which suggested that CEACAM5 could facilitate MERS-CoV entry in conjunction with DPP4 despite not being able to support MERS-CoV entry independently. Taken together, the results of our study identified CEACAM5 as a novel cell surface binding target of MERS-CoV that facilitates MERS-CoV infection by augmenting the attachment of the virus to the host cell surface. IMPORTANCE Infection with the Middle East respiratory syndrome coronavirus (MERS-CoV) is associated with the highest mortality rate among all known human-pathogenic coronaviruses. Currently, there are no approved vaccines or therapeutics against MERS-CoV infection. The identification of carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) as a novel cell surface binding target of MERS-CoV advanced our knowledge on the cell binding biology of MERS-CoV. Importantly, CEACAM5 could potentiate the entry of MERS-CoV by functioning as an attachment factor. In this regard, CEACAM5 could serve as a novel target, in addition to dipeptidyl peptidase-4 (DPP4), in the development of antiviral strategies for MERS-CoV.
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Abstract
Coronaviruses (CoVs) have a remarkable potential to change tropism. This is particularly illustrated over the last 15 years by the emergence of two zoonotic CoVs, the severe acute respiratory syndrome (SARS)- and Middle East respiratory syndrome (MERS)-CoV. Due to their inherent genetic variability, it is inevitable that new cross-species transmission events of these enveloped, positive-stranded RNA viruses will occur. Research into these medical and veterinary important pathogens—sparked by the SARS and MERS outbreaks—revealed important principles of inter- and intraspecies tropism changes. The primary determinant of CoV tropism is the viral spike (S) entry protein. Trimers of the S glycoproteins on the virion surface accommodate binding to a cell surface receptor and fusion of the viral and cellular membrane. Recently, high-resolution structures of two CoV S proteins have been elucidated by single-particle cryo-electron microscopy. Using this new structural insight, we review the changes in the S protein that relate to changes in virus tropism. Different concepts underlie these tropism changes at the cellular, tissue, and host species level, including the promiscuity or adaptability of S proteins to orthologous receptors, alterations in the proteolytic cleavage activation as well as changes in the S protein metastability. A thorough understanding of the key role of the S protein in CoV entry is critical to further our understanding of virus cross-species transmission and pathogenesis and for development of intervention strategies.
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Zhang D, Huang X, Zhang X, Cao S, Wen X, Wen Y, Wu R, Liang E. Construction of an oral vaccine for transmissible gastroenteritis virus based on the TGEV N gene expressed in an attenuated Salmonella typhimurium vector. J Virol Methods 2015; 227:6-13. [PMID: 26297958 DOI: 10.1016/j.jviromet.2015.08.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Revised: 08/17/2015] [Accepted: 08/17/2015] [Indexed: 01/16/2023]
Abstract
This research aimed to develop an oral vaccine for transmissible gastroenteritis virus (TGEV) based on the TGEV N gene expressed in an attenuated Salmonella typhimurium vector and aimed to evaluate the vaccine's immune response in piglets. Recombinant plasmid pVAX-N was transformed into competent cells of attenuated S. typhimurium SL7207 via electroporation. After it was identified via RT-PCR and double digestion, the screened recombinant bacteria presenting pVAX-N were named SL7207 (pVAX-N). To evaluate the safety and stability of the developed vaccine, different dosages (5 × 10(8), 1 × 10(9), and 2 × 10(9) CFU/mice) of SL7207 (pVAX-N) were inoculated to 6-week-old mice. Piglets below 20 days of age were dosed with 1 × 10(12) CFU. Humoral (neutralization titer and specific IgG), cellular (interleukin-4, γ-interferon, and peripheral lymphocyte proliferation), and mucosal (sIgA) immune responses were detected and evaluated. The three immunizing dosages were determined to be safe for mice and were completely eliminated 8 weeks after the first inoculation. Results of antibody and cytokine detection indicated that SL7207 (pVAX-N) could significantly induce antibody-IgG, antibody-IgA, interleukin-4, and γ-interferon, whose value was maximized on the 6th week. Results confirmed that the recombinant vaccine increased the proliferation of peripheral T lymphocyte. In conclusion, the oral vaccine was developed successfully, and the vaccine could significantly induce humoral, cellular, and mucosal immune responses in piglets.
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Affiliation(s)
- Dan Zhang
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China
| | - Xiaobo Huang
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China; Sichuan Science-observation Experiment Station of Veterinary Drugs and Veterinary Biological Technology, Ministry of Agriculture, Ya'an 625014, China.
| | - Xiaohui Zhang
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China
| | - Sanjie Cao
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China; Sichuan Science-observation Experiment Station of Veterinary Drugs and Veterinary Biological Technology, Ministry of Agriculture, Ya'an 625014, China
| | - Xintian Wen
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China; Sichuan Science-observation Experiment Station of Veterinary Drugs and Veterinary Biological Technology, Ministry of Agriculture, Ya'an 625014, China
| | - Yiping Wen
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China; Sichuan Science-observation Experiment Station of Veterinary Drugs and Veterinary Biological Technology, Ministry of Agriculture, Ya'an 625014, China
| | - Rui Wu
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China; Sichuan Science-observation Experiment Station of Veterinary Drugs and Veterinary Biological Technology, Ministry of Agriculture, Ya'an 625014, China
| | - Entao Liang
- Laboratory of Animal Infectious Disease and Microarray, Laboratory of Zoonosis and Pig Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Ya'an 625014, China
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Suo S, Wang X, Zarlenga D, Bu RE, Ren Y, Ren X. Phage display for identifying peptides that bind the spike protein of transmissible gastroenteritis virus and possess diagnostic potential. Virus Genes 2015; 51:51-6. [PMID: 26013256 PMCID: PMC7089269 DOI: 10.1007/s11262-015-1208-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 05/15/2015] [Indexed: 02/06/2023]
Abstract
The spike (S) protein of porcine transmissible gastroenteritis virus (TGEV) is located within the viral envelope and is the only structural protein that possesses epitopes capable of inducing virus-neutralizing antibodies. Among the four N-terminal antigenic sites A, B, C, and D, site A and to a lesser extent site D (S-AD) induce key neutralizing antibodies. Recently, we expressed S-AD (rS-AD) in recombinant form. In the current study, we used the rS-AD as an immobilized target to identify peptides from a phage-display library with application for diagnosis. Among the 9 phages selected that specifically bound to rS-AD, the phage bearing the peptide TLNMHLFPFHTG bound with the highest affinity and was subsequently used to develop a phage-based ELISA for TGEV. When compared with conventional antibody-based ELISA, phage-mediated ELISA was more sensitive; however, it did not perform better than semi-quantitative RT-PCR, though phage-mediated ELISA was quicker and easier to set up.
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Affiliation(s)
- Siqingaowa Suo
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, 59 Mucai Street, Xiangfang District, Harbin, 150030, China,
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Jung K, Saif LJ. Porcine epidemic diarrhea virus infection: Etiology, epidemiology, pathogenesis and immunoprophylaxis. Vet J 2015; 204:134-43. [PMID: 25841898 PMCID: PMC7110711 DOI: 10.1016/j.tvjl.2015.02.017] [Citation(s) in RCA: 344] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 02/16/2015] [Accepted: 02/18/2015] [Indexed: 12/03/2022]
Abstract
The etiology and epidemiology of PEDV are described. The disease mechanisms and pathogenesis of PEDV are reviewed. Epidemic PED versus endemic PED are demonstrated. Immunoprophylaxis as a preventive strategy is discussed.
Porcine epidemic diarrhea virus (PEDV), a member of the genera Alphacoronavirus in the family Coronaviridae, causes acute diarrhea/vomiting, dehydration and high mortality in seronegative neonatal piglets. For the last three decades, PEDV infection has resulted in significant economic losses in the European and Asian pig industries, but in 2013–2014 the disease was also reported in the US, Canada and Mexico. The PED epidemic in the US, from April 2013 to the present, has led to the loss of more than 10% of the US pig population. The disappearance and re-emergence of epidemic PED indicates that the virus is able to escape from current vaccination protocols, biosecurity and control systems. Endemic PED is a significant problem, which is exacerbated by the emergence (or potential importation) of multiple PEDV variants. Epidemic PEDV strains spread rapidly and cause a high number of pig deaths. These strains are highly enteropathogenic and acutely infect villous epithelial cells of the entire small and large intestines although the jejunum and ileum are the primary sites. PEDV infections cause acute, severe atrophic enteritis accompanied by viremia that leads to profound diarrhea and vomiting, followed by extensive dehydration, which is the major cause of death in nursing piglets. A comprehensive understanding of the pathogenic characteristics of epidemic or endemic PEDV strains is needed to prevent and control the disease in affected regions and to develop an effective vaccine. This review focuses on the etiology, epidemiology, disease mechanisms and pathogenesis as well as immunoprophylaxis against PEDV infection.
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Affiliation(s)
- Kwonil Jung
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA.
| | - Linda J Saif
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, Wooster, Ohio, USA
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Lv X, Wang P, Bai R, Cong Y, Suo S, Ren X, Chen C. Inhibitory effect of silver nanomaterials on transmissible virus-induced host cell infections. Biomaterials 2014; 35:4195-203. [PMID: 24524838 PMCID: PMC7112386 DOI: 10.1016/j.biomaterials.2014.01.054] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 01/22/2014] [Indexed: 01/01/2023]
Abstract
Coronaviruses belong to the family Coronaviridae, which primarily cause infection of the upper respiratory and gastrointestinal tract of hosts. Transmissible gastroenteritis virus (TGEV) is an economically significant coronavirus that can cause severe diarrhea in pigs. Silver nanomaterials (Ag NMs) have attracted great interests in recent years due to their excellent anti-microorganism properties. Herein, four representative Ag NMs including spherical Ag nanoparticles (Ag NPs, NM-300), two kinds of silver nanowires (XFJ011) and silver colloids (XFJ04) were selected to study their inhibitory effect on TGEV-induced host cell infection in vitro. Ag NPs were uniformly distributed, with particle sizes less than 20 nm by characterization of environmental scanning electron microscope and transmission electron microscope. Two types of silver nanowires were 60 nm and 400 nm in diameter, respectively. The average diameter of the silver colloids was approximately 10 nm. TGEV infection induced the occurring of apoptosis in swine testicle (ST) cells, down-regulated the expression of Bcl-2, up-regulated the expression of Bax, altered mitochondrial membrane potential, activated p38 MAPK signal pathway, and increased expression of p53 as evidenced by immunofluorescence assays, real-time PCR, flow cytometry and Western blot. Under non-toxic concentrations, Ag NPs and silver nanowires significantly diminished the infectivity of TGEV in ST cells. Moreover, further results showed that Ag NPs and silver nanowires decreased the number of apoptotic cells induced by TGEV through regulating p38/mitochondria-caspase-3 signaling pathway. Our data indicate that Ag NMs are effective in prevention of TGEV-mediated cell infection as a virucidal agent or as an inhibitor of viral entry and the present findings may provide new insights into antiviral therapy of coronaviruses.
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Affiliation(s)
- Xiaonan Lv
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, No. 59, Mucai Street, Xiangfang District, Harbin 150030, PR China; National Center for Nanoscience and Technology of China, No. 11, Beiyitiao, Zhongguancun, Beijing 100190, PR China
| | - Peng Wang
- National Center for Nanoscience and Technology of China, No. 11, Beiyitiao, Zhongguancun, Beijing 100190, PR China
| | - Ru Bai
- National Center for Nanoscience and Technology of China, No. 11, Beiyitiao, Zhongguancun, Beijing 100190, PR China
| | - Yingying Cong
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, No. 59, Mucai Street, Xiangfang District, Harbin 150030, PR China
| | - Siqingaowa Suo
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, No. 59, Mucai Street, Xiangfang District, Harbin 150030, PR China
| | - Xiaofeng Ren
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, No. 59, Mucai Street, Xiangfang District, Harbin 150030, PR China.
| | - Chunying Chen
- National Center for Nanoscience and Technology of China, No. 11, Beiyitiao, Zhongguancun, Beijing 100190, PR China.
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Kwon HJ, Ryu YB, Kim YM, Song N, Kim CY, Rho MC, Jeong JH, Cho KO, Lee WS, Park SJ. In vitro antiviral activity of phlorotannins isolated from Ecklonia cava against porcine epidemic diarrhea coronavirus infection and hemagglutination. Bioorg Med Chem 2013; 21:4706-13. [PMID: 23746631 PMCID: PMC7127107 DOI: 10.1016/j.bmc.2013.04.085] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 04/18/2013] [Accepted: 04/27/2013] [Indexed: 01/09/2023]
Abstract
Despite the prepdominat agent causing severe entero-pathogenic diarrhea in swine, there are no effective therapeutical treatment of porcine epidemic diarrhea virus (PEDV). In this study, we evaluated the antiviral activity of five phlorotannins isolated from Ecklonia cava (E. cava) against PEDV. In vitro antiviral activity was tested using two different assay strategies: (1) blockage of the binding of virus to cells (simultaneous-treatment assay) and (2) inhibition of viral replication (post-treatment assay). In simultaneous-treatment assay, compounds 2-5 except compound 1 exhibited antiviral activities of a 50% inhibitory concentration (IC₅₀) with the ranging from 10.8 ± 1.4 to 22.5 ± 2.2 μM against PEDV. Compounds 1-5 were completely blocked binding of viral spike protein to sialic acids at less than 36.6 μM concentrations by hemagglutination inhibition. Moreover, compounds 4 and 5 of five phlorotannins inhibited viral replication with IC₅₀ values of 12.2 ± 2.8 and 14.6 ± 1.3 μM in the post-treatment assay, respectively. During virus replication steps, compounds 4 and 5 exhibited stronger inhibition of viral RNA and viral protein synthesis in late stages (18 and 24 h) than in early stages (6 and 12 h). Interestingly, compounds 4 and 5 inhibited both viral entry by hemagglutination inhibition and viral replication by inhibition of viral RNA and viral protein synthesis, but not viral protease. These results suggest that compounds isolated from E. cava have strong antiviral activity against PEDV, inhibiting viral entry and/or viral replication, and may be developed into natural therapeutic drugs against coronavirus infection.
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Affiliation(s)
- Hyung-Jun Kwon
- Infection Control Material Research Center, AI Control Material Research Center and Bioindustrial Process Reasearch Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeongeup-si, Jeonbuk 580-185, Republic of Korea
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28
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Abstract
Sialic acid linked to glycoproteins and gangliosides is used by many viruses as a receptor for cell entry. These viruses include important human and animal pathogens, such as influenza, parainfluenza, mumps, corona, noro, rota, and DNA tumor viruses. Attachment to sialic acid is mediated by receptor binding proteins that are constituents of viral envelopes or exposed at the surface of non-enveloped viruses. Some of these viruses are also equipped with a neuraminidase or a sialyl-O-acetyl-esterase. These receptor-destroying enzymes promote virus release from infected cells and neutralize sialic acid-containing soluble proteins interfering with cell surface binding of the virus. Variations in the receptor specificity are important determinants for host range, tissue tropism, pathogenicity, and transmissibility of these viruses.
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Affiliation(s)
| | - Philippe Delannoy
- Lille University of Science and Technology, Villeneuve d'Ascq Cedex, France
| | - Mark von Itzstein
- Institute for Glycomics, Griffith University, Southport, Queensland Australia
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29
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Löfling J, Lyi SM, Parrish CR, Varki A. Canine and feline parvoviruses preferentially recognize the non-human cell surface sialic acid N-glycolylneuraminic acid. Virology 2013; 440:89-96. [PMID: 23497940 DOI: 10.1016/j.virol.2013.02.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 02/12/2013] [Accepted: 02/13/2013] [Indexed: 12/27/2022]
Abstract
Feline panleukopenia virus (FPV) is a pathogen whose canine-adapted form (canine parvovirus (CPV)) emerged in 1978. These viruses infect by binding host transferrin receptor type-1 (TfR), but also hemagglutinate erythrocytes. We show that hemagglutination involves selective recognition of the non-human sialic acid N-glycolylneuraminic acid (Neu5Gc) but not N-acetylneuraminic acid (Neu5Ac), which differs by only one oxygen atom from Neu5Gc. Overexpression of α2-6 sialyltransferase did not change binding, indicating that both α2-3 and α2-6 linkages are recognized. However, Neu5Gc expression on target cells did not enhance CPV or FPV infection in vitro. Thus, the conserved Neu5Gc-binding preference of these viruses likely plays a role in the natural history of the virus in vivo. Further studies must clarify relationships between virus infection and host Neu5Gc expression. As a first step, we show that transcripts of CMAH (which generates Neu5Gc from Neu5Ac) are at very low levels in Western dog breed cells.
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Affiliation(s)
- Jonas Löfling
- Department of Medicine, Center for Academic Research and Training in Anthropogeny, 9500 Gilman Drive, University of California, San Diego, La Jolla, CA 92093, USA
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Man C, Yu X. Cloning and Sequence Analysis of N Gene of Transmissible Gastroenteritis Virus HYM-09 Isolated from Dog in China. INDIAN JOURNAL OF VIROLOGY : AN OFFICIAL ORGAN OF INDIAN VIROLOGICAL SOCIETY 2012; 23:364-7. [PMID: 24293826 PMCID: PMC3550793 DOI: 10.1007/s13337-012-0072-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 05/28/2012] [Indexed: 11/30/2022]
Abstract
Transmissible gastroenteritis virus (TGEV) is the etiological agent of TGE, and dogs are potential carriers of TGEV. In this study, genomic RNA were extracted from TGEV designated HYM-09 isolated from dog naturally infected with TGEV. The nucleocapsid (N) gene of HYM-09 was amplified by RT-PCR and cloned into pMD18-T vector. The N gene cDNA was sequenced and encompassed an open reading frame of 1,149 nucleotides, encoding a 382-amino acids protein. Sequence analyses of the N genes were performed, including homologous comparison, phylogenetic tree analysis and residue substitution analysis. The results showed that there existed some unique mutations in the HYM-09 isolate N gene, but HYM-09 N gene shared over 96 % homologous identities compared with 12 TGEV reference strains derived from other regions or countries respectively. The phylogenetic tree analysis revealed that the HYM-09 branched into the most strains group. This study shows that the nucleotide sequence analysis can form a base or further study on the mutation trend of non-porcine TGEV.
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Affiliation(s)
- Chaolai Man
- />Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province, College of Life Science and Technology, Harbin Normal University, Harbin, 150025 People’s Republic of China
| | - Xiaolong Yu
- />Institute of Animal Science, Heilongjiang Academy of Agricultural Sciences, NO. 368 Xuefu Road, Harbin, 150086 Heilongjiang People’s Republic of China
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He L, Zhang YM, Dong LJ, Cheng M, Wang J, Tang QH, Wang G. In vitro inhibition of transmissible gastroenteritis coronavirus replication in swine testicular cells by short hairpin RNAs targeting the ORF 7 gene. Virol J 2012; 9:176. [PMID: 22929207 PMCID: PMC3492083 DOI: 10.1186/1743-422x-9-176] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Accepted: 08/22/2012] [Indexed: 11/18/2022] Open
Abstract
Background Transmissible gastroenteritis (TGE) is a highly contagious viral disease of swine, characterized by severe vomiting, diarrhea, and high mortality. Currently, the vaccines for it are only partially effective and no specific drug is available for treatment of TGE virus (TGEV) infection. RNA interference has been confirmed as a new approach for controlling viral infections. In this study, the inhibitory effect of short hairpin RNAs (shRNAs) targeting the ORF 7 gene of TGEV on virus replication was examined. Results Four theoretically effective sequences of TGEV ORF 7 gene were designed and selected for construction of shRNA expression plasmids. In the reporter assays, three of four shRNA expression plasmids were able to inhibit significantly the expression of ORF 7 gene and replication of TGEV, as shown by real-time quantitative RT-PCR analysis of viral ORF 7 and N genes and detection of virus titers (TCID50/ml). Stable swine testicular (ST) cells expressing the shRNAs were established. Observation of the cytopathic effect and apoptosis, as well as a cell proliferation assay demonstrated that the three shRNAs were capable of protecting ST cells against TGEV destruction, with high specificity and efficiency. Conclusions Our results indicated that plasmid-transcribed shRNAs targeting the ORF 7 gene in the TGEV genome effectively inhibited expression of the viral target gene and viral replication in vitro. These findings provide evidence that the shRNAs have potential therapeutic application for treatment of TGE.
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Affiliation(s)
- Lei He
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China
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Belouzard S, Millet JK, Licitra BN, Whittaker GR. Mechanisms of coronavirus cell entry mediated by the viral spike protein. Viruses 2012; 4:1011-33. [PMID: 22816037 PMCID: PMC3397359 DOI: 10.3390/v4061011] [Citation(s) in RCA: 878] [Impact Index Per Article: 73.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 06/13/2012] [Accepted: 06/14/2012] [Indexed: 12/12/2022] Open
Abstract
Coronaviruses are enveloped positive-stranded RNA viruses that replicate in the cytoplasm. To deliver their nucleocapsid into the host cell, they rely on the fusion of their envelope with the host cell membrane. The spike glycoprotein (S) mediates virus entry and is a primary determinant of cell tropism and pathogenesis. It is classified as a class I fusion protein, and is responsible for binding to the receptor on the host cell as well as mediating the fusion of host and viral membranes—A process driven by major conformational changes of the S protein. This review discusses coronavirus entry mechanisms focusing on the different triggers used by coronaviruses to initiate the conformational change of the S protein: receptor binding, low pH exposure and proteolytic activation. We also highlight commonalities between coronavirus S proteins and other class I viral fusion proteins, as well as distinctive features that confer distinct tropism, pathogenicity and host interspecies transmission characteristics to coronaviruses.
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Affiliation(s)
- Sandrine Belouzard
- Center for Infection and Immunity of Lille, CNRS UMR8204, INSERM U1019, Institut Pasteur de Lille, Université Lille Nord de France, 59000 Lille, France;
| | - Jean K. Millet
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA; (J.K.M.); (B.N.L.)
| | - Beth N. Licitra
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA; (J.K.M.); (B.N.L.)
| | - Gary R. Whittaker
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA; (J.K.M.); (B.N.L.)
- Author to whom correspondence should be addressed; ; Tel.: +1-607-253-4021; Fax: +1-607-253-3384
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Yu TF, Shao SL, Xu XJ, Lv JW, Li M. Prediction of TGEV Spike Protein Secondary Structure and B Cell Epitopes. ADVANCES IN INTELLIGENT AND SOFT COMPUTING 2012. [PMCID: PMC7123739 DOI: 10.1007/978-3-642-27537-1_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The spike gene of TGEV TH98 strain was translated into amino sequence by Editseq. The secondary structure and B cell epitope of spike protein of TGEV TH98 strain were predicted by Protean. Combining the results according to these methods, the spike protein of TGEV TH98 strain has complicated secondary structure. There are several epitopes of the B-cells in spike protein, including 43-56aa, 97-104aa, 117-128aa, 132-173aa, 238-257aa, 391-398aa, 535-706aa, 779-799aa, 918-987aa, 1165-1200aa, 1257-1266aa and 1430-1446aa.
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Schwegmann-Wessels C, Bauer S, Winter C, Enjuanes L, Laude H, Herrler G. The sialic acid binding activity of the S protein facilitates infection by porcine transmissible gastroenteritis coronavirus. Virol J 2011; 8:435. [PMID: 21910859 PMCID: PMC3184106 DOI: 10.1186/1743-422x-8-435] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Accepted: 09/12/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transmissible gastroenteritis virus (TGEV) has a sialic acid binding activity that is believed to be important for enteropathogenicity, but that has so far appeared to be dispensable for infection of cultured cells. The aims of this study were to determine the effect of sialic acid binding for the infection of cultured cells under unfavorable conditions, and comparison of TGEV strains and mutants, as well as the avian coronavirus IBV concerning their dependence on the sialic acid binding activity. METHODS The infectivity of different viruses was analyzed by a plaque assay after adsorption times of 5, 20, and 60 min. Prior to infection, cultured cells were either treated with neuraminidase to deplete sialic acids from the cell surface, or mock-treated. In a second approach, pre-treatment of the virus with porcine intestinal mucin was performed, followed by the plaque assay after a 5 min adsorption time. A student's t-test was used to verify the significance of the results. RESULTS Desialylation of cells only had a minor effect on the infection by TGEV strain Purdue 46 when an adsorption period of 60 min was allowed for initiation of infection. However, when the adsorption time was reduced to 5 min the infectivity on desialylated cells decreased by more than 60%. A TGEV PUR46 mutant (HAD3) deficient in sialic acid binding showed a 77% lower titer than the parental virus after a 5 min adsorption time. After an adsorption time of 60 min the titer of HAD3 was 58% lower than that of TGEV PUR46. Another TGEV strain, TGEV Miller, and IBV Beaudette showed a reduction in infectivity after neuraminidase treatment of the cultured cells irrespective of the virion adsorption time. CONCLUSIONS Our results suggest that the sialic acid binding activity facilitates the infection by TGEV under unfavorable environmental conditions. The dependence on the sialic acid binding activity for an efficient infection differs in the analyzed TGEV strains.
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Ren X, Meng F, Yin J, Li G, Li X, Wang C, Herrler G. Action mechanisms of lithium chloride on cell infection by transmissible gastroenteritis coronavirus. PLoS One 2011; 6:e18669. [PMID: 21573100 PMCID: PMC3089605 DOI: 10.1371/journal.pone.0018669] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Accepted: 03/15/2011] [Indexed: 12/16/2022] Open
Abstract
Transmissible gastroenteritis virus (TGEV) is a porcine coronavirus. Lithium chloride (LiCl) has been found to be effective against several DNA viruses, such as Herpes simplex virus and vaccinia virus. Recently, we and others have reported the inhibitory effect of LiCl on avian infectious bronchitis coronavirus (IBV) infection, an RNA virus. In the current study, the action mechanism of LiCl on cell infection by TGEV was investigated. Plaque assays and 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenyl tetrazoliumbromide (MTT) assays showed that the cell infection by TGEV was inhibited in a dose-dependent manner, when LiCl was added to virus-infected cells; the cell infection was not affected when either cells or viruses were pretreated with the drug. The inhibition of TGEV infection in vitro by LiCl was observed at different virus doses and with different cell lines. The inhibitory effect of LiCl against TGEV infection and transcription was confirmed by RT-PCR and real-time PCR targeting viral S and 3CL-protease genes. The time-of-addition effect of the drug on TGEV infection indicated that LiCl acted on the initial and late stage of TGEV infection. The production of virus was not detected at 36 h post-infection due to the drug treatment. Moreover, immunofluorescence (IF) and flow cytometry analyses based on staining of Annexin V and propidium iodide staining of nuclei indicated that early and late cell apoptosis induced by TGEV was inhibited efficiently. The ability of LiCl to inhibit apoptosis was investigated by IF analysis of caspase-3 expression. Our data indicate that LiCl inhibits TGEV infection by exerting an anti-apoptotic effect. The inhibitory effect of LiCl was also observed with porcine epidemic diarrhea coronavirus. Together with other reports concerning the inhibitory effect of lithium salts on IBV in cell culture, our results indicate that LiCl may be a potent agent against porcine and avian coronaviruses.
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Affiliation(s)
- Xiaofeng Ren
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
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Ren X, Liu B, Yin J, Zhang H, Li G. Phage displayed peptides recognizing porcine aminopeptidase N inhibit transmissible gastroenteritis coronavirus infection in vitro. Virology 2010; 410:299-306. [PMID: 21176936 PMCID: PMC7111919 DOI: 10.1016/j.virol.2010.11.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 06/22/2010] [Accepted: 11/16/2010] [Indexed: 12/03/2022]
Abstract
Porcine aminopeptidase N (pAPN) is a cellular receptor of transmissible gastroenteritis virus (TGEV), a porcine coronavirus. Interaction between the spike (S) protein of TGEV and pAPN initiates cell infection. Small molecules, especially peptides are an expanding area for therapy or diagnostic assays for viral diseases. Here, the peptides capable of binding the pAPN were, for the first time, identified by biopanning using a random 12-mer peptide library to the immobilized protein. Three chemically synthesized peptides recognizing the pAPN showed effective inhibition ability to TGEV infection in vitro. A putative TxxF motif was identified in the S protein of TGEV. Phages bearing the specific peptides interacted with the pAPN in ELISA. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays confirmed the protective effect of the peptides on cell infection by TGEV. Moreover, the excellent immune responses in mice induced by the identified phages provided the possibility to develop novel phage-based vaccines.
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Affiliation(s)
- Xiaofeng Ren
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
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37
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Yin J, Glende J, Schwegmann-Wessels C, Enjuanes L, Herrler G, Ren X. Cholesterol is important for a post-adsorption step in the entry process of transmissible gastroenteritis virus. Antiviral Res 2010; 88:311-6. [PMID: 20951168 PMCID: PMC7114218 DOI: 10.1016/j.antiviral.2010.10.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 10/05/2010] [Accepted: 10/05/2010] [Indexed: 12/13/2022]
Abstract
Cholesterol is a major constituent of detergent-resistant membrane microdomains (DRMs). We localized transmissible gastroenteritis virus (TGEV) spike (S) protein in DRMs in the viral envelope. Though S protein was not solubilized by cold non-ionic detergents, this behavior was unchanged when cholesterol was depleted from viral membrane by methyl-β-cyclodextrin (MβCD) and the protein did not comigrate with cellular DRM marker proteins in flotation analyses. Therefore, the S protein is not anchored in the viral membrane DRMs as they are known to occur in the plasma membrane. Cholesterol depletion from viral membrane may not affect the adsorption process as neither the sialic acid binding activity nor the binding to aminopeptidase N was reduced post-MβCD treatment. Reduced infectivity of cholesterol-depleted TGEV was observed only when the adsorption process occurred at 37 °C but not when the virus was applied at 4 °C. Cholesterol is important for a post-adsorption step, allowing membrane rearrangements that facilitate virus entry.
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Affiliation(s)
- Jiechao Yin
- Northeast Agricultural University, Harbin, China
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38
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Ren X, Li G, Liu B. Binding characterization of determinants in porcine aminopeptidase N, the cellular receptor for transmissible gastroenteritis virus. J Biotechnol 2010; 150:202-6. [PMID: 20643168 PMCID: PMC7114188 DOI: 10.1016/j.jbiotec.2010.07.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2010] [Revised: 07/02/2010] [Accepted: 07/12/2010] [Indexed: 11/27/2022]
Abstract
Four truncated porcine aminopeptidase N (pAPN, a cellular receptor for porcine coronaviruses) proteins were expressed in prokaryotic cells. The recognizing of a specific serum against pAPN to these proteins was investigated by enzyme-linked immunosorbent assay (ELISA) and immunoblotting. The binding ability of the proteins to transmissible gastroenteritis virus (TGEV), a porcine coronavirus, was analyzed by ELISA. The inhibitory effect of these proteins to cell infection by TGEV was analyzed using plaque assays. Our data indicate that three truncated pAPNs positively reacted with the specific antiserum and the major binding regions of pAPN were limited in regions 36aa–223aa, 349aa–591aa and 592–963aa. The proteins showed discrepant binding activity to either pAPN antibody or TGE virions. Moreover, the truncated proteins blocked the infection of cells by TGEV to different extent. The results suggest that the major antibody-binding domains of pAPN may associate with the receptor-binding determinants. The role of APN is discussed in the context of virus receptor usage.
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Affiliation(s)
- Xiaofeng Ren
- College of Veterinary Medicine, Northeast Agricultural University, 59 Mucai Street, 150030 Harbin, China.
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39
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Abstract
Coronaviruses most often infect the respiratory or intestinal tract. Transmissible gastroenteritis virus (TGEV), a group 1 coronavirus, infects the porcine small intestine. Piglets up to the age of 3 weeks die from diarrhea caused by the viral gastroenteritis unless they are protected by antibodies. In addition to the cellular receptor, porcine aminopeptidase N, the TGEV spike protein binds to sialic acid residues. We have shown that the sialic acid binding activity mediates the binding of TGEV to a mucin-like glycoprotein present in porcine brush border membranes. This was shown by performing a virus overlay binding assay with proteins obtained from brush border membranes by lectin precipitation. Because of the reactivity with specific lectins we assume that the recognized glycoprotein has the characteristics of a mucin.
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Schwegmann-Weßels C, Glende J, Ren X, Qu X, Deng H, Enjuanes L, Herrler G. Comparison of vesicular stomatitis virus pseudotyped with the S proteins from a porcine and a human coronavirus. J Gen Virol 2009; 90:1724-1729. [PMID: 19264610 DOI: 10.1099/vir.0.009704-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The surface proteins S of severe acute respiratory syndrome coronavirus (SARS-CoV) and transmissible gastroenteritis virus (TGEV) were compared for their ability to mediate infection of viral pseudotypes based on vesicular stomatitis virus (VSV). The cell tropism of the respective pseudotypes corresponded to the tropism of the viruses from which the S protein was derived. Higher infectivity values were obtained with the SARS-CoV S protein than with the TGEV S protein. Differences were observed with respect to the importance of the cytoplasmic tail and the membrane anchor of the S proteins. In the case of the SARS-CoV S protein, truncation of the cytoplasmic tail resulted in increased infectivity. For the TGEV S protein, the inactivation of an intracellular retention signal in the cytoplasmic tail was required. Exchange of the membrane anchor of the S proteins led to a low infection efficiency. Our results indicate that related glycoproteins may show substantial differences in their ability to mediate pseudotype infection.
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Affiliation(s)
| | - Jörg Glende
- Institute of Virology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Xiaofeng Ren
- College of Veterinary Medicine, Northeast Agricultural University, 59 Mucai Street, 150030 Harbin, PR China
- Institute of Virology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Xiuxia Qu
- Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing 100871, PR China
| | - Hongkui Deng
- Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing 100871, PR China
| | - Luis Enjuanes
- Centro Nacional de Biotecnología, CSIC, Department of Molecular and Cell Biology, Campus Universitario de Cantoblanco, Darwin 3, 28049 Madrid, Spain
| | - Georg Herrler
- Institute of Virology, University of Veterinary Medicine Hannover, Hannover, Germany
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Tsunoda I, Libbey JE, Fujinami RS. Theiler's murine encephalomyelitis virus attachment to the gastrointestinal tract is associated with sialic acid binding. J Neurovirol 2008; 15:81-9. [PMID: 19115131 PMCID: PMC2882804 DOI: 10.1080/13550280802380563] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
DA and GDVII are strains of Theiler’s murine encephalomyelitis virus (TMEV). DA virus mutant DApB encodes VP2 puff B of GDVII, whereas DApBL2M contains VP1 loop II of GDVII with a point mutation in VP2 puff B. Neuraminidase treatment of cells inhibited infection by DA and DApB, but not GDVII or DApBL2M viruses; sialic acid (SA) binding correlated with virus persistence. In virus binding assays to intestine sections, all four TMEVs bound goblet cells and the mucus of the epithelium that was SA dependent. Therefore, differences in SA composition on different cell types can affect tropism and infection.
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Affiliation(s)
- Ikuo Tsunoda
- Department of Pathology, University of Utah School of Medicine, 30 North 1900 East, Salt Lake City, UT 84132, USA
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Importance of cholesterol for infection of cells by transmissible gastroenteritis virus. Virus Res 2008; 137:220-4. [PMID: 18727942 PMCID: PMC7114513 DOI: 10.1016/j.virusres.2008.07.023] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 07/11/2008] [Accepted: 07/16/2008] [Indexed: 12/31/2022]
Abstract
In this study, we addressed the question whether cholesterol is important for transmissible gastroenteritis virus (TGEV), a porcine coronavirus, in the initiation of an infection. We found that cholesterol depletion from the cellular membrane by methyl-β-cyclodextrin (MβCD) significantly impaired the efficiency of TGEV infection. Infectivity was also reduced after depleting cholesterol from the viral envelope. This finding is surprising because coronaviruses bud from a pre-Golgi compartment which is expected to be low in cholesterol compared to the plasma membrane. Addition of exogenous cholesterol resulted in a restoration of the infectivity confirming our conclusion that efficient TGEV infection requires cholesterol in both the viral and the cellular membranes. Our data raise the possibility that the viral and cellular proteins involved in the entry process may be associated with cholesterol-rich membrane microdomains.
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43
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Cavanagh D. Coronavirus avian infectious bronchitis virus. Vet Res 2007; 38:281-97. [PMID: 17296157 DOI: 10.1051/vetres:2006055] [Citation(s) in RCA: 654] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Accepted: 09/22/2006] [Indexed: 01/05/2023] Open
Abstract
Infectious bronchitis virus (IBV), the coronavirus of the chicken (Gallus gallus), is one of the foremost causes of economic loss within the poultry industry, affecting the performance of both meat-type and egg-laying birds. The virus replicates not only in the epithelium of upper and lower respiratory tract tissues, but also in many tissues along the alimentary tract and elsewhere e.g. kidney, oviduct and testes. It can be detected in both respiratory and faecal material. There is increasing evidence that IBV can infect species of bird other than the chicken. Interestingly breeds of chicken vary with respect to the severity of infection with IBV, which may be related to the immune response. Probably the major reason for the high profile of IBV is the existence of a very large number of serotypes. Both live and inactivated IB vaccines are used extensively, the latter requiring priming by the former. Their effectiveness is diminished by poor cross-protection. The nature of the protective immune response to IBV is poorly understood. What is known is that the surface spike protein, indeed the amino-terminal S1 half, is sufficient to induce good protective immunity. There is increasing evidence that only a few amino acid differences amongst S proteins are sufficient to have a detrimental impact on cross-protection. Experimental vector IB vaccines and genetically manipulated IBVs--with heterologous spike protein genes--have produced promising results, including in the context of in ovo vaccination.
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Affiliation(s)
- Dave Cavanagh
- Institute for Animal Health, Compton Laboratory, Compton, Newbury, Berkshire RG20 7NN, United Kingdom.
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44
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Abstract
Among coronaviruses, several members are able to interact with sialic acids. For bovine coronavirus (BCoV) and related viruses, binding to cell surface components containing
N-acetyl-9-
O-acetylneuraminic acid is essential for initiation of an infection. These viruses resemble influenza C viruses because they share not only the receptor determinant, but also the presence of an acetylesterase that releases the 9-
O-acetyl group from sialic acid and thus abolishes the ability of the respective sialoglycoconjugate to function as a receptor for BCoV. As in the case of influenza viruses, the receptor-destroying enzyme of BCoV is believed to facilitate the spread of virus infection by removing receptor determinants from the surface of infected cells and by preventing the formation of virus aggregates. Another coronavirus, porcine transmissible gastroenteritis virus (TGEV) preferentially recognizes
N-glycolylneuraminic acid. TGEV does not contain a receptor-destroying enzyme and does not depend on the sialic acid binding activity for infection of cultured cells. However, binding to sialic acids is required for the enteropathogenicity of TGEV. Interaction with sialoglycoconjugates may help the virus to pass through the sialic acid-rich mucus layer that covers the viral target cells in the epithelium of the small intestine. We discuss that the BCoV group of viruses may have evolved from a TGEV-like ancestor by acquiring an acetylesterase gene through heterologous recombination.
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Affiliation(s)
- Christel Schwegmann-Weßels
- Institut für Virologie, Stiftung Tierärztliche Hochschule Hannover, Bünteweg 17, 30559 Hannover, Germany
| | - Georg Herrler
- Institut für Virologie, Stiftung Tierärztliche Hochschule Hannover, Bünteweg 17, 30559 Hannover, Germany
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Ren X, Glende J, Al-Falah M, de Vries V, Schwegmann-Wessels C, Qu X, Tan L, Tschernig T, Deng H, Naim HY, Herrler G. Analysis of ACE2 in polarized epithelial cells: surface expression and function as receptor for severe acute respiratory syndrome-associated coronavirus. J Gen Virol 2006; 87:1691-1695. [PMID: 16690935 DOI: 10.1099/vir.0.81749-0] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The primary target of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is epithelial cells in the respiratory and intestinal tract. The cellular receptor for SARS-CoV, angiotensin-converting enzyme 2 (ACE2), has been shown to be localized on the apical plasma membrane of polarized respiratory epithelial cells and to mediate infection from the apical side of these cells. Here, these results were confirmed and extended by including a colon carcinoma cell line (Caco-2), a lung carcinoma cell line (Calu-3) and Vero E6 cells in our analysis. All three cell types expressed human ACE2 on the apical membrane domain and were infected via this route, as determined with vesicular stomatitis virus pseudotypes containing the S protein of SARS-CoV. In a histological analysis of the respiratory tract, ACE2 was detected in the trachea, main bronchus and alveoli, and occasionally also in the small bronchi. These data will help us to understand the pathogenesis of SARS-CoV infection.
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Affiliation(s)
- Xiaofeng Ren
- Institut für Virologie, Tierärztliche Hochschule Hannover, Bünteweg 17, D-30559 Hannover, Germany
| | - Jörg Glende
- Institut für Virologie, Tierärztliche Hochschule Hannover, Bünteweg 17, D-30559 Hannover, Germany
| | - Marwan Al-Falah
- Institut für Physiologische Chemie, Tierärztliche Hochschule Hannover, Bünteweg 17, D-30559 Hannover, Germany
| | - Victor de Vries
- Institut für funktionelle und angewandte Anatomie, Medizinische Hochschule Hannover, Carl-Neuberg-Straße, D-30625 Hannover, Germany
| | | | - Xiuxia Qu
- Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Lei Tan
- Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Thomas Tschernig
- Institut für funktionelle und angewandte Anatomie, Medizinische Hochschule Hannover, Carl-Neuberg-Straße, D-30625 Hannover, Germany
| | - Hongkui Deng
- Department of Cell Biology and Genetics, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China
| | - Hassan Y Naim
- Institut für Physiologische Chemie, Tierärztliche Hochschule Hannover, Bünteweg 17, D-30559 Hannover, Germany
| | - Georg Herrler
- Institut für Virologie, Tierärztliche Hochschule Hannover, Bünteweg 17, D-30559 Hannover, Germany
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Yin J, Ren X, Tian Z, Li Y. Assembly of pseudorabies virus genome-based transfer vehicle carrying major antigen sites of S gene of transmissible gastroenteritis virus: potential perspective for developing live vector vaccines. Biologicals 2006; 35:55-61. [PMID: 16731004 PMCID: PMC7128284 DOI: 10.1016/j.biologicals.2006.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Revised: 12/20/2005] [Accepted: 02/01/2006] [Indexed: 01/08/2023] Open
Abstract
Two severe porcine infectious diseases, pseudorabies (PR) and transmissible gastroenteritis (TGE) caused by pseudorabies virus (PRV) and transmissible gastroenteritis virus (TGEV) respectively often result in serious economic loss in animal husbandry worldwide. Vaccination is the important prevention means against both infections. To achieve a PRV genome-based virus live vector, aiming at further TGEV/PRV bivalent vaccine development, a recombinant plasmid pUG was constructed via inserting partial PK and full-length gG genes of PRV strain Bartha K-61 amplified into pUC119 vector. In parallel, another recombinant pHS was generated by introducing a fragment designated S1 encoding the major antigen sites of S gene from TGEV strain TH-98 into a prokaryotic expression vector pPROEX HTc. The SV40 polyA sequence was then inserted into the downstream of S1 fragment of pHS. The continuous region containing S1fragment, SV40 polyA and four single restriction enzyme sites digested from pHS was subcloned into the downstream of gG promoter of pUG. In addition, a LacZ reporter gene was introduced into the universal transfer vector named pUGS-LacZ. Subsequently, a PRV genome-based virus live vector was generated via homologous recombination. The functionally effective vector was purified and partially characterized. Moreover, the potential advantages of this system are discussed.
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Affiliation(s)
- Jiechao Yin
- Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, 59 Mucai Street, 150030 Harbin, PR China
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47
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Desselberger U. International symposium: RNA viruses shuttling between animal and man. Future Virol 2006. [DOI: 10.2217/17460794.1.3.305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Ulrich Desselberger
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Molecular Immunology, Padriciano 99, 34012 Trieste, Italy
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48
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Lassnig C, Kolb A, Strobl B, Enjuanes L, Müller M. Studying human pathogens in animal models: fine tuning the humanized mouse. Transgenic Res 2006; 14:803-6. [PMID: 16315087 PMCID: PMC7088949 DOI: 10.1007/s11248-005-1676-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Accepted: 08/03/2005] [Indexed: 01/12/2023]
Abstract
Humanized mice are crucial tools for studying human pathogens in systemic situations. An animal model of human coronavirus infectious disease has been generated by gene transfer of the human receptor for virus-cell interaction (aminopeptidase N, APN, CD13) into mice. We showed that in vitro and in vivo infections across the species barrier differ in their requirements. Transgenic cells were susceptible to human coronavirus HCoV-229E infection demonstrating the requirement of hAPN for viral cell entry. Transgenic mice, however, could not be infected suggesting additional requirements for in vivo virus susceptibility. Crossing hAPN transgenic mice with interferon unresponsive Stat1−/− mice resulted in markedly enhanced virus replication in vitro but did not result in detectable virus replication in vivo. Adaptation of the human virus to murine cells led to successful infection of the humanized transgenic mice. Future genetic engineering approaches are suggested to provide animal models for the better understanding of human infectious diseases.
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Affiliation(s)
- Caroline Lassnig
- Department of Agrobiotechnology, IFA-Tulln, Institute of Biotechnology in Animal Production, University of Natural Resources and Applied Life Sciences, 3430 Tulln, Austria
- Austrian Center for Biomodels and Transgenetics (ÖZBT), University of Veterinary Medicine, 1210 Vienna, Austria
| | | | - Birgit Strobl
- Austrian Center for Biomodels and Transgenetics (ÖZBT), University of Veterinary Medicine, 1210 Vienna, Austria
| | - Luis Enjuanes
- Department of Molecular and Cell Biology, Centro Nacional de Biotecnologia, Consejo Superior de Investigaciones Cientificas, 28049 Madrid, Spain
| | - Mathias Müller
- Department of Agrobiotechnology, IFA-Tulln, Institute of Biotechnology in Animal Production, University of Natural Resources and Applied Life Sciences, 3430 Tulln, Austria
- Austrian Center for Biomodels and Transgenetics (ÖZBT), University of Veterinary Medicine, 1210 Vienna, Austria
- Institute of Animal Breeding and Genetics, University of Veterinary Medicine, 1210 Vienna, Austria
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49
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Ma G, Feng Y, Gao F, Wang J, Liu C, Li Y. Biochemical and biophysical characterization of the transmissible gastroenteritis coronavirus fusion core. Biochem Biophys Res Commun 2005; 337:1301-7. [PMID: 16236266 PMCID: PMC7092864 DOI: 10.1016/j.bbrc.2005.09.189] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2005] [Accepted: 09/30/2005] [Indexed: 11/25/2022]
Abstract
Transmissible gastroenteritis coronavirus (TGEV) is one of the most destructive agents, responsible for the enteric infections that are lethal for suckling piglets, causing enormous economic loss to the porcine fostering industry every year. Although it has been known that TGEV spiker protein is essential for the viral entry for many years, the detail knowledge of the TGEV fusion protein core is still very limited. Here, we report that TGEV fusion core (HR1-SGGRGG-HR2), in vitro expressed in GST prokaryotic expression system, shares the typical properties of the trimer of coiled-coil heterodimer (six α-helix bundle), which has been confirmed by a combined series of biochemical and biophysical evidences including size exclusion chromatography (gel-filtration), chemical crossing, and circular diagram. The 3D homologous structure model presents its most likely structure, extremely similar to those of the coronaviruses documented. Taken together, TGEV spiker protein belongs to the class I fusion protein, characterized by the existence of two heptad-repeat (HR) regions, HR1 and HR2, and the present knowledge about the truncated TGEV fusion protein core may facilitate in the design of the small molecule or polypeptide drugs targeting the membrane fusion between TGEV and its host.
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Affiliation(s)
- Guangpeng Ma
- Department of Preventive Veterinary, College of Veterinary Medicine, Northeast Agriculture University, 150030 Harbin, PR China
| | - Youjun Feng
- Laboratory of Molecular Immunology and Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, PR China
- Graduate School of the Chinese Academy of Sciences, PR China
| | - Feng Gao
- Laboratory of Molecular Immunology and Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, PR China
- China Agricultural University, Beijing 100094, PR China
| | - Jinzi Wang
- China Agricultural University, Beijing 100094, PR China
| | - Cheng Liu
- China Agricultural University, Beijing 100094, PR China
| | - Yijing Li
- Department of Preventive Veterinary, College of Veterinary Medicine, Northeast Agriculture University, 150030 Harbin, PR China
- Corresponding author. Fax: +86 0451 5113336.
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50
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Yin JC, Ren XF, Li YJ. Molecular cloning and phylogenetic analysis of ORF7 region of chinese isolate TH-98 from transmissible gastroenteritis virus. Virus Genes 2005; 30:395-401. [PMID: 15830158 PMCID: PMC7089185 DOI: 10.1007/s11262-004-6783-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Accepted: 12/15/2004] [Indexed: 11/04/2022]
Abstract
Genomic RNA was extracted from a Chinese isolate of porcine transmissible gastroenteritis virus (TGEV) designated TH-98. Employing RT-PCR technique to amplify ORF7 sequence of TGEV, which located at the 3' end of TGEV genome and is poorly understood functionally so far. A recombinant named pPROEX HTc-hp was constructed via inserting ORF7 gene into prokaryotic expression vector pPROEX HTc. The recombinant was sequenced and compared the DNA and its deduced amino acid (aa) sequences with that of some reference strains after restriction endonuclease and PCR analysis. The ORF7 gene named hp gene (Genbank accession number: AY337931) consists of 237 bp in length encoding a hydrophobic protein (HP) of 78 aa with a molecular weight of 9.1 kDa. The sequences of hp gene and Hp protein share 89%-97% and 87%-96% homologous identities compared with 11 TGEV reference strains derived from other regions or countries respectively, which revealed that there are significant variation within-strains, even though the ORF7 region is relatively conservative. In addition, a phylogenetic tree based on these ORF7 DNA sequences was generated, and the tree topology suggests that possible recombination events happened in the evolutionary history of TGEV.
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Affiliation(s)
- Jie-Chao Yin
- Department of Preventive Veterinary, College of Veterinary Medicine, Northeast Agriculture University, 59 Mucai Street, 150030 Harbin, China
| | - Xiao-Feng Ren
- Department of Preventive Veterinary, College of Veterinary Medicine, Northeast Agriculture University, 59 Mucai Street, 150030 Harbin, China
- Institute for Virology, School of Veterinary Medicine Hannover, 17 Buentweg, D-30559 Hannover, Germany
| | - Yi-Jing Li
- Department of Preventive Veterinary, College of Veterinary Medicine, Northeast Agriculture University, 59 Mucai Street, 150030 Harbin, China
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