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Bandaw T, Gebremeskel HF, Muluneh A, Mengistu TS, Kebede IA. Seroprevalence and molecular detection of foot and mouth disease virus in cattle in selected districts of Wolaita Zone, Southern Ethiopia. Sci Rep 2024; 14:7929. [PMID: 38575673 PMCID: PMC10994912 DOI: 10.1038/s41598-024-57404-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Accepted: 03/18/2024] [Indexed: 04/06/2024] Open
Abstract
Foot and mouth disease (FMD) is a highly contagious, endemic, and acute viral cattle ailment that causes major economic damage in Ethiopia. Although several serotypes of the FMD virus have been detected in Ethiopia, there is no documented information about the disease's current serostatus and serotypes circulating in the Wolaita zone. Thus, from March to December 2022, a cross-sectional study was conducted to evaluate FMDV seroprevalence, molecular detection, and serotype identification in three Wolaita Zone sites. A multistage sample procedure was used to choose three peasant associations from each study region, namely Wolaita Sodo, Offa district, and Boloso sore district. A systematic random sampling technique was employed to pick 384 cattle from the population for the seroprevalence research, and 10 epithelial tissue samples were purposefully taken from outbreak individuals for molecular detection of FMDV. The sera were examined using 3ABC FMD NSP Competition ELISA to find antibodies against FMDV non-structural proteins, whereas epithelial tissue samples were analyzed for molecular detection using real-time RT-PCR, and sandwich ELISA was used to determine the circulating serotypes. A multivariable logistic regression model was used to evaluate the associated risk variables. The total seroprevalence of FMD in cattle was 46.88% (95% CI 41.86-51.88), with Wolaita Sodo Town having the highest seroprevalence (63.28%). As a consequence, multivariable logistic regression analysis revealed that animal age, herd size, and interaction with wildlife were all substantially related to FMD seroprevalence (p < 0.05). During molecular detection, only SAT-2 serotypes were found in 10 tissue samples. Thus, investigating FMD outbreaks and identifying serotypes and risk factors for seropositivity are critical steps in developing effective control and prevention strategies based on the kind of circulating serotype. Moreover, further research for animal species other than cattle was encouraged.
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Affiliation(s)
- Tamenech Bandaw
- School of Veterinary Medicine, Wolaita Sodo University, P. O. Box 138, Wolaita Sodo, Ethiopia
| | | | | | - Tilaye Shibiru Mengistu
- School of Veterinary Medicine, Wolaita Sodo University, P. O. Box 138, Wolaita Sodo, Ethiopia
| | - Isayas Asefa Kebede
- School of Veterinary Medicine, Ambo University, P. O. Box 19, Guder, Ethiopia.
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Kim Y, Pool E, Kim E, Dampalla CS, Nguyen HN, Johnson DK, Lovell S, Groutas WC, Chang KO. Potent small molecule inhibitors against the 3C protease of foot-and-mouth disease virus. Microbiol Spectr 2024; 12:e0337223. [PMID: 38466127 PMCID: PMC10986521 DOI: 10.1128/spectrum.03372-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 01/18/2024] [Indexed: 03/12/2024] Open
Abstract
Foot-and-mouth disease (FMD) is one of the most devastating diseases of livestock which can cause significant economic losses, especially when introduced to FMD-free countries. FMD virus (FMDV) belongs to the family Picornaviridae and is antigenically heterogeneous with seven established serotypes. The prevailing preventive and control strategies are limited to restriction of animal movement and elimination of infected or exposed animals, which can be potentially combined with vaccination. However, FMD vaccination has limitations including delayed protection and lack of cross-protection against different serotypes. Recently, antiviral drug use for FMD outbreaks has increasingly been recognized as a potential tool to augment the existing early response strategies, but limited research has been reported on potential antiviral compounds for FMDV. FMDV 3C protease (3Cpro) cleaves the viral-encoded polyprotein into mature and functional proteins during viral replication. The essential role of viral 3Cpro in viral replication and the high conservation of 3Cpro among different FMDV serotypes make it an excellent target for antiviral drug development. We have previously reported multiple series of inhibitors against picornavirus 3Cpro or 3C-like proteases (3CLpros) encoded by coronaviruses or caliciviruses. In this study, we conducted structure-activity relationship studies for our in-house focused compound library containing 3Cpro or 3CLpro inhibitors against FMDV 3Cpro using enzyme and cell-based assays. Herein, we report the discovery of aldehyde and α-ketoamide inhibitors of FMDV 3Cpro with high potency. These data inform future preclinical studies that are related to the advancement of these compounds further along the drug development pathway.IMPORTANCEFood-and-mouth disease (FMD) virus (FMDV) causes devastating disease in cloven-hoofed animals with a significant economic impact. Emergency response to FMD outbreaks to limit FMD spread is critical, and the use of antivirals may overcome the limitations of existing control measures by providing immediate protection for susceptible animals. FMDV encodes 3C protease (3Cpro), which is essential for virus replication and an attractive target for antiviral drug discovery. Here, we report a structure-activity relationship study on multiple series of protease inhibitors and identified potent inhibitors of FMDV 3Cpro. Our results suggest that these compounds have the potential for further development as FMD antivirals.
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Affiliation(s)
- Yunjeong Kim
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA
| | - Emma Pool
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA
| | - Eunji Kim
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA
| | | | - Harry Nhat Nguyen
- Department of Chemistry, Wichita State University, Wichita, Kansas, USA
| | - David K. Johnson
- Computational Chemical Biology Core, The University of Kansas, Lawrence, Kansas, USA
| | - Scott Lovell
- Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, Lawrence, Kansas, USA
| | | | - Kyeong-Ok Chang
- Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA
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Theerawatanasirikul S, Lueangaramkul V, Pantanam A, Mana N, Semkum P, Lekcharoensuk P. Small Molecules Targeting 3C Protease Inhibit FMDV Replication and Exhibit Virucidal Effect in Cell-Based Assays. Viruses 2023; 15:1887. [PMID: 37766293 PMCID: PMC10535379 DOI: 10.3390/v15091887] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Revised: 08/30/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Foot-and-mouth disease (FMD) is a highly contagious disease in cloven-hoofed animals, caused by the foot-and-mouth disease virus (FMDV). It is endemic in Asia and Africa but spreads sporadically throughout the world, resulting in significant losses in the livestock industry. Effective anti-FMDV therapeutics could be a supportive control strategy. Herein, we utilized computer-aided, structure-based virtual screening to filter lead compounds from the National Cancer Institute (NCI) diversity and mechanical libraries using FMDV 3C protease (3Cpro) as the target. Seven hit compounds were further examined via cell-based antiviral and intracellular protease assays, in which two compounds (NSC116640 and NSC332670) strongly inhibited FMDV, with EC50 values at the micromolar level of 2.88 µM (SI = 73.15) and 5.92 µM (SI = 11.11), respectively. These compounds could inactivate extracellular virus directly in a virucidal assay by reducing 1.00 to 2.27 log TCID50 of the viral titers in 0-60 min. In addition, the time-of-addition assay revealed that NSC116640 inhibited FMDV at the early stage of infection (0-8 h), while NSC332670 diminished virus titers when added simultaneously at infection (0 h). Both compounds showed good FMDV 3Cpro inhibition with IC50 values of 10.85 µM (NSC116640) and 4.21 µM (NSC332670). The molecular docking of the compounds on FMDV 3Cpro showed their specific interactions with amino acids in the catalytic triad of FMDV 3Cpro. Both preferentially reacted with enzymes and proteases in physicochemical and ADME analysis studies. The results revealed two novel small molecules with antiviral activities against FMDV and probably related picornaviruses.
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Affiliation(s)
- Sirin Theerawatanasirikul
- Department of Anatomy, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand
| | - Varanya Lueangaramkul
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (V.L.); (A.P.); (N.M.); (P.S.)
| | - Achiraya Pantanam
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (V.L.); (A.P.); (N.M.); (P.S.)
| | - Natjira Mana
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (V.L.); (A.P.); (N.M.); (P.S.)
| | - Ploypailin Semkum
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (V.L.); (A.P.); (N.M.); (P.S.)
| | - Porntippa Lekcharoensuk
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (V.L.); (A.P.); (N.M.); (P.S.)
- Center of Advanced Studies in Agriculture and Food, KU Institute, Bangkok 10900, Thailand
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4
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Saadh MJ. Silver nanoparticles inhibit goatpox virus replication. Arch Virol 2023; 168:32. [PMID: 36604362 DOI: 10.1007/s00705-022-05667-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/31/2022] [Indexed: 01/07/2023]
Abstract
No effective drugs against goatpox virus (GTPV) exist despite the high morbidity and mortality (up to 100%) caused by this virus. In this study, the antiviral activity of silver nanoparticles (AgNPs) against GTPV, a member of the genus Capripoxvirus, was evaluated. Piper betle leaf extract was used as a reducing agent during the biological synthesis of AgNPs from silver nitrate. The AgNPs were characterized using ultraviolet/visible (UV/vis) absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). AgNPs were tested at different concentrations as antiviral agents against GTPV, and the reduction in the median tissue culture infectious dose (TCID50/mL) was used to quantitate antiviral activity. AgNPs caused significant inhibition of GTPV replication by preventing virus entry into the host cell. Pre-treatment of cells with AgNPs caused a slight reduction in infectivity, but this did not significantly correlate with the effect on virus attachment. AgNPs also appeared to significantly reduce the viral genome copy number. This study demonstrates that the AgNPs are capable of inhibiting GTPV replication in vitro.
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O-2-Alkylated Cytosine Acyclic Nucleoside Phosphonamidate Prodrugs Display Pan-Genotype Antiviral Activity against African Swine Fever Virus. mSphere 2022; 7:e0037822. [PMID: 36317894 PMCID: PMC9769911 DOI: 10.1128/msphere.00378-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
African swine fever virus (ASFV) causes a highly contagious hemorrhagic disease with case fatality rates approaching 100% in domestic pigs. ASFV is responsible for substantial economic losses, but despite ongoing efforts, no vaccine or antiviral agent is currently available. Attempts to control the spread of ASFV are dependent on early detection, adherence to biosecurity measures, and culling of infected herds. However, an effective antiviral agent may be used in lieu of or in conjunction with a vaccine to effectively curb ASFV outbreaks. The dose-dependent antiviral activities of two amidate prodrugs (compounds 1a and 1b) of O-2-alkylated 3-fluoro-2-(phosphonomethoxy)propyl cytosine [(R)-O-2-alkylated FPMPC] against ASFV isolates of four different genotypes were determined. Both compounds were found to inhibit ASFV progeny virus output by >90% at noncytotoxic concentrations (<25 μM) in primary porcine macrophages. Analysis of viral transcription and viral protein synthesis indicated that these acyclic nucleotide analogues inhibited late gene expression. Interestingly, time-of-addition studies suggest different viral targets of the compounds, which may be attributed to their differing amino acid prodrug moieties. In view of their promising antiviral activity, these nucleotide analogues merit further evaluation as potential prophylactic and/or therapeutic agents against ASFV infection and their antiviral efficacy in vivo should be considered. IMPORTANCE African swine fever virus is a highly contagious hemorrhagic viral disease. Since its transcontinental spread to Georgia in 2007, ASFV has continued to spread across the globe into countries previously without infection. It is responsible for substantial losses in the domestic pig population and presents a significant threat to the global swine industry. Despite ongoing efforts, there are no vaccines currently available; in their absence, antiviral agents may be a viable alternative. The significance of our research is in identifying the pan-genotype antiviral activity of prodrugs of O-2-alkylated 3-fluoro-2-(phosphonomethoxy)propyl cytosine, which will drive further research on the development of these compounds as antivirals against ASFV.
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Nikunjkumar P, Tamil Selvan RP, Bhanuprakash V. Ribavirin as a curative and prophylactic agent against foot and mouth disease virus infection in C57BL/6 suckling and adult mice model. Virusdisease 2021; 32:737-747. [PMID: 34901324 DOI: 10.1007/s13337-021-00746-8] [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: 06/07/2021] [Accepted: 09/28/2021] [Indexed: 11/29/2022] Open
Abstract
Despite the availability of control measures for foot-and-mouth disease (FMD), the application of antiviral agents is imperative due to certain limitations in the prevention and control of FMD. This study pertains to systematic in vivo investigation of ribavirin as a prophylactic/curative agent, both in suckling and adult C57BL/6 mice against foot-and-mouth disease virus (FMDV) infection. In the adult mice, antiviral efficacy was assessed based on standard clinical score, body weight, and viral load. Only 13.33 to 33.33% of adult mice exhibited disease-specific symptoms following treatment and infection and vice versa, respectively, indicating the antiviral efficacy of the ribavirin. Further, the distribution of virus in different vital organs following ribavirin treatment and virus infection, and vice versa using SYBR green-based real-time PCR is reported. In the blood sample, the viral RNA was detected as early as two days post-infection and there was a significant reduction in virus titer (1000 to 10,000-folds) in the treatment groups compared to the infection control group. Animals receiving ribavirin had significantly lower organ virus titers at 2, 4, 6, 9, and 14 days post-challenge (dpc) than placebo-treated. In suckling mice, the treatment groups were 100% protected/cured compared to the control group. Thus, our data demonstrate that ribavirin may provide a feasible therapeutic approach to prevent as well as to treat FMDV infection. Supplementary Information The online version contains supplementary material available at 10.1007/s13337-021-00746-8.
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Affiliation(s)
- Patel Nikunjkumar
- FMD Vaccine Quality Control Laboratory, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), HA Farm (P.O), Hebbal, Bengaluru, Karnataka 560 024 India
| | - Ramasamy Periyasamy Tamil Selvan
- FMD Vaccine Quality Control Laboratory, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), HA Farm (P.O), Hebbal, Bengaluru, Karnataka 560 024 India
| | - Veerakyathappa Bhanuprakash
- FMD Vaccine Quality Control Laboratory, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), HA Farm (P.O), Hebbal, Bengaluru, Karnataka 560 024 India
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7
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Saadh M. Epigallocatechin gallate (EGCG) combined with zinc sulfate inhibits Peste des petits ruminants virus entry and replication. Saudi J Biol Sci 2021; 28:6674-6678. [PMID: 34764780 PMCID: PMC8568804 DOI: 10.1016/j.sjbs.2021.07.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 07/08/2021] [Accepted: 07/11/2021] [Indexed: 12/31/2022] Open
Abstract
Despite the fact that the Peste des petits ruminants virus (PPRV) leads to high morbidity and mortality (up to 100%), antiviral drugs against PPRV are not available. The aim of this study was to estimate the dose of epigallocatechin gallate (EGCG) co-administered with zinc (II) ions as an antiviral agent against PPRV. Treatment of PPRV-infectedVero cells with EGCG and zinc sulfate (zinc II) was administered, and antiviral activities against PPRV in infected Vero cells was evaluated by determination of virus yields, expressed as logTCID50/mL. Cytotoxicity was determined using the tetrazolium-based MTS test. Zinc sulfate at 1.1 mg/mL and EGCG at 25 μM showed low potentiated and potentiated antiviral activities against PPRV, respectively. These agents caused significant inhibition of PPRV in Vero cells (p < 0.05) with a reduction in logTCID50/mL by up to 3-fold. The combination of EGCG (25 μM) and zinc sulfate (1.1 mg/mL) was observed to have strong antiviral activity (p < 0.01) against PPRV with a reduction in logTCID50/mL of the virus up to 4-times without causing any host cell cytotoxicity. This study is the first one to prove that the zinc II has the capability of stimulating EGCG to inhibit in vitro PPRV entry. Moreover, this combination appears capable of reducing infection resistance by hindering viral adaptation.
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Affiliation(s)
- Mohamed Saadh
- Faculty of Pharmacy, Middle East University, Amman 11831, Jordan.,Faculty of Pharmacy, Philadelphia University , Amman, Jordan
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Theerawatanasirikul S, Thangthamniyom N, Kuo CJ, Semkum P, Phecharat N, Chankeeree P, Lekcharoensuk P. Natural Phytochemicals, Luteolin and Isoginkgetin, Inhibit 3C Protease and Infection of FMDV, In Silico and In Vitro. Viruses 2021; 13:2118. [PMID: 34834926 PMCID: PMC8625466 DOI: 10.3390/v13112118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/13/2021] [Accepted: 10/18/2021] [Indexed: 12/15/2022] Open
Abstract
Foot-and-mouth-disease virus (FMDV) is a picornavirus that causes a highly contagious disease of cloven-hoofed animals resulting in economic losses worldwide. The 3C protease (3Cpro) is the main protease essential in the picornavirus life cycle, which is an attractive antiviral target. Here, we used computer-aided virtual screening to filter potential anti-FMDV agents from the natural phytochemical compound libraries. The top 23 filtered compounds were examined for anti-FMDV activities by a cell-based assay, two of which possessed antiviral effects. In the viral and post-viral entry experiments, luteolin and isoginkgetin could significantly block FMDV growth with low 50% effective concentrations (EC50). Moreover, these flavonoids could reduce the viral load as determined by RT-qPCR. However, their prophylactic activities were less effective. Both the cell-based and the fluorescence resonance energy transfer (FRET)-based protease assays confirmed that isoginkgetin was a potent FMDV 3Cpro inhibitor with a 50% inhibition concentration (IC50) of 39.03 ± 0.05 and 65.3 ± 1.7 μM, respectively, whereas luteolin was less effective. Analyses of the protein-ligand interactions revealed that both compounds fit in the substrate-binding pocket and reacted to the key enzymatic residues of the 3Cpro. Our findings suggested that luteolin and isoginkgetin are promising antiviral agents for FMDV and other picornaviruses.
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Affiliation(s)
- Sirin Theerawatanasirikul
- Department of Anatomy, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand;
| | - Nattarat Thangthamniyom
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (N.T.); (P.S.); (N.P.); (P.C.)
| | - Chih-Jung Kuo
- Department of Veterinary Medicine, National Chung Hsing University, Taichung 40227, Taiwan
| | - Ploypailin Semkum
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (N.T.); (P.S.); (N.P.); (P.C.)
| | - Nantawan Phecharat
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (N.T.); (P.S.); (N.P.); (P.C.)
| | - Penpitcha Chankeeree
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (N.T.); (P.S.); (N.P.); (P.C.)
| | - Porntippa Lekcharoensuk
- Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand; (N.T.); (P.S.); (N.P.); (P.C.)
- Center for Advanced Studies in Agriculture and Food, Kasetsart University Institute for Advanced Studies, Kasetsart University, Bangkok 10900, Thailand
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Kariuki CK, Magez S. Improving the yield of recalcitrant Nanobodies® by simple modifications to the standard protocol. Protein Expr Purif 2021; 185:105906. [PMID: 33991675 DOI: 10.1016/j.pep.2021.105906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/04/2021] [Accepted: 05/06/2021] [Indexed: 11/15/2022]
Abstract
Nanobodies are single-domain antibody constructs derived from the variable regions of heavy chain only (VHH) camelid IgGs. Their small size and single gene format make them amenable to various molecular biology applications that require a protein affinity-based approach. These features, in addition to their high solubility, allows their periplasmic expression, extraction and purification in E. coli systems with relative ease, using standardized protocols. However, some Nanobodies are recalcitrant to periplasmic expression, extraction and purification within E. coli systems. To improve their expression would require either a change in the expression host, vector or an increased scale of expression, all of which entail an increase in the complexity of their expression, and production cost. However, as shown here, specific changes in the existing standard E. coli culture protocol, aimed at reducing breakdown of selective antibiotic pressure, increasing the initial culture inoculum and improving transport to the periplasmic space, rescued the expression of several such refractory Nanobodies. The periplasmic extraction protocol was also changed to ensure efficient osmolysis, prevent both protein degradation and prevent downstream chelation of Ni2+ ions during IMAC purification. Adoption of this protocol will lead to an improvement of the expression of Nanobodies in general, and specifically, those that are recalcitrant.
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Affiliation(s)
- Christopher K Kariuki
- Laboratory of Cellular and Molecular Interactions (CMIM), Vrije Universiteit Brussels, Brussels, Belgium; Department of Tropical and Infectious Diseases, Institute of Primate Research (IPR), Nairobi, Kenya.
| | - Stefan Magez
- Laboratory of Cellular and Molecular Interactions (CMIM), Vrije Universiteit Brussels, Brussels, Belgium; Laboratory for Biomedical Research, Ghent University Global Campus, Yeonsu-Gu, Incheon, South Korea; Department of Biochemistry and Microbiology, Universiteit Gent, Ledeganckstraat 35, 9000, Gent, Belgium.
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Chander Y, Kumar R, Khandelwal N, Singh N, Shringi BN, Barua S, Kumar N. Role of p38 mitogen-activated protein kinase signalling in virus replication and potential for developing broad spectrum antiviral drugs. Rev Med Virol 2021; 31:1-16. [PMID: 33450133 DOI: 10.1002/rmv.2217] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 12/11/2022]
Abstract
Mitogen-activated protein kinases (MAPKs) play a key role in complex cellular processes such as proliferation, development, differentiation, transformation and apoptosis. Mammals express at least four distinctly regulated groups of MAPKs which include extracellular signal-related kinases (ERK)-1/2, p38 proteins, Jun amino-terminal kinases (JNK1/2/3) and ERK5. p38 MAPK is activated by a wide range of cellular stresses and modulates activity of several downstream kinases and transcription factors which are involved in regulating cytoskeleton remodeling, cell cycle modulation, inflammation, antiviral response and apoptosis. In viral infections, activation of cell signalling pathways is part of the cellular defense mechanism with the basic aim of inducing an antiviral state. However, viruses can exploit enhanced cell signalling activities to support various stages of their replication cycles. Kinase activity can be inhibited by small molecule chemical inhibitors, so one strategy to develop antiviral drugs is to target these cellular signalling pathways. In this review, we provide an overview on the current understanding of various cellular and viral events regulated by the p38 signalling pathway, with a special emphasis on targeting these events for antiviral drug development which might identify candidates with broad spectrum activity.
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Affiliation(s)
- Yogesh Chander
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana, India.,Department of Bio and Nano Technology, Guru Jambeshwar University of Science and Technology, Hisar, Haryana, India
| | - Ram Kumar
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana, India.,Department of Veterinary Microbiology and Biotechnology, Rajasthan University of Veterinary and Animal Sciences, Bikaner, India
| | - Nitin Khandelwal
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana, India.,Department of Biotechnology, GLA University, Mathura, India
| | - Namita Singh
- Department of Bio and Nano Technology, Guru Jambeshwar University of Science and Technology, Hisar, Haryana, India
| | - Brij Nandan Shringi
- Department of Veterinary Microbiology and Biotechnology, Rajasthan University of Veterinary and Animal Sciences, Bikaner, India
| | - Sanjay Barua
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana, India
| | - Naveen Kumar
- National Centre for Veterinary Type Cultures, ICAR-National Research Centre on Equines, Hisar, Haryana, India
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Abstract
Antiviral drugs have traditionally been developed by directly targeting essential viral components. However, this strategy often fails due to the rapid generation of drug-resistant viruses. Recent genome-wide approaches, such as those employing small interfering RNA (siRNA) or clustered regularly interspaced short palindromic repeats (CRISPR) or those using small molecule chemical inhibitors targeting the cellular "kinome," have been used successfully to identify cellular factors that can support virus replication. Since some of these cellular factors are critical for virus replication, but are dispensable for the host, they can serve as novel targets for antiviral drug development. In addition, potentiation of immune responses, regulation of cytokine storms, and modulation of epigenetic changes upon virus infections are also feasible approaches to control infections. Because it is less likely that viruses will mutate to replace missing cellular functions, the chance of generating drug-resistant mutants with host-targeted inhibitor approaches is minimized. However, drug resistance against some host-directed agents can, in fact, occur under certain circumstances, such as long-term selection pressure of a host-directed antiviral agent that can allow the virus the opportunity to adapt to use an alternate host factor or to alter its affinity toward the target that confers resistance. This review describes novel approaches for antiviral drug development with a focus on host-directed therapies and the potential mechanisms that may account for the acquisition of antiviral drug resistance against host-directed agents.
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Abstract
Foot and mouth disease (FMD) is a highly contagious and economically important disease of cloven-hoofed animals, which is endemic in Ethiopia. An outbreak follow-up study was undertaken to quantify the transmission parameters of FMD in the crop-livestock mixed (CLM) system and commercial dairy farms in selected areas of northwest Ethiopia. The transmission parameters were quantified using a generalised linear model (GLM) based on a susceptible-infectious-recovered (SIR) epidemic model. The per day average transmission rate between animals was 0.26 (95% CI 0.22-0.32) and 0.33 (95% CI 0.21-0.57) in the CLM system and in the commercial dairy farms, respectively. The average basic reproduction ratio of FMD was 1.68 (95% CI 1.42-2.07) in the CLM system and 1.98 (95% CI 1.26-3.42) in the commercial dairy farms. The medium per day transmission rate and moderate basic reproduction ratio observed in this study indicated that a vaccination coverage needed to stop transmission of the disease in these populations might not be very high.
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13
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Yadav P, Choudhury S, Barua S, Khandelwal N, Kumar N, Shukla A, Garg SK. Polyalthia longifolia leaves methanolic extract targets entry and budding of viruses-an in vitro experimental study against paramyxoviruses. JOURNAL OF ETHNOPHARMACOLOGY 2020; 248:112279. [PMID: 31600562 DOI: 10.1016/j.jep.2019.112279] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 06/04/2019] [Accepted: 10/04/2019] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Synthetic antiviral drugs have several limitations including high cost. Thus research on antiviral property of medicinal plants is continuously gaining importance. Polyalthia longifolia possesses several medicinal properties and has been used in traditional ayurvedic medicine for treatment of dermatological ailments as kushta, visarpa/herpes virus infection and also to treat pyrexia of unknown origin as mentioned in Visarpa Chikitsa. AIM OF THE STUDY Keeping in view the cytotoxic, anti-cancer activity and antiviral efficacy of Polyalthia longifolia against herpes, present study was undertaken to evaluate the in vitro antiviral activity of methanolic extract of Polyalthia longifolia leaves, if any, and to unravel the possible target(s)/mechanism of action. MATERIAL AND METHODS Antiviral activity of Polyalthia longifolia methanolic extract was studied using Vero cell lines against paramyxoviruses, namely-peste des petits ruminants virus (PPRV) and Newcastle disease virus (NDV). Cytotoxicity of the test extract was evaluated employing MTT assay. Virucidal activity, and viral-attachment, virus entry and release assays were determined in Vero cells using standard experimental protocols. The viral RNA in the virus-infected cells was quantified by qRT-PCR. RESULTS At non-cytotoxic concentration, methanolic extract of Polyalthia longifolia leaves was found to inhibit the replication of PPRV and NDV at viral entry and budding level, whereas other steps of viral life cycle such as attachment and RNA synthesis remained unaffected. CONCLUSIONS Polyalthia longifolia leaves extract possesses promising antiviral activity against paramyxoviruses and acts by inhibiting the entry and budding of viruses; and this plant extract evidently possesses excellent and promising potential for development of effective herbal antiviral drug.
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Affiliation(s)
- Prashant Yadav
- Department of Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan (DUVASU), Mathura, India.
| | - Soumen Choudhury
- Department of Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan (DUVASU), Mathura, India.
| | - Sanjay Barua
- National Centre for Veterinary Type Culture Collections (NCVTCC), ICAR-National Research Centre on Equines, Hisar, Haryana, India.
| | - Nitin Khandelwal
- National Centre for Veterinary Type Culture Collections (NCVTCC), ICAR-National Research Centre on Equines, Hisar, Haryana, India.
| | - Naveen Kumar
- National Centre for Veterinary Type Culture Collections (NCVTCC), ICAR-National Research Centre on Equines, Hisar, Haryana, India; Division of Goat Health, ICAR-Central Institute for Research on Goats, Makhdoom, Mathura, India.
| | - Amit Shukla
- Department of Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan (DUVASU), Mathura, India.
| | - Satish K Garg
- Department of Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, U.P. Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go-Anusandhan Sansthan (DUVASU), Mathura, India.
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Soumajit S, Tamil Selvan RP, Bhanuprakash V. In vitro antiviral efficacy of pleconaril and ribavirin on foot-and-mouth disease virus replication. Virusdisease 2019; 30:562-570. [PMID: 31890754 DOI: 10.1007/s13337-019-00559-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 11/26/2019] [Indexed: 10/25/2022] Open
Abstract
Antiviral therapy is a promising strategy to control acute viral infections. FMDV causes an acute infection and the vaccination provides a protective immunity 7 days post immunization. If the infection is uncontained, then it affects the entire herd. In such circumstances, if antiviral drug is administered the infection can be checked in a herd. Ribavirin is known to cure persistently infected BHK21 cells with FMD virus. However, there have been no systematic studies on antiviral activity of ribavirin against FMDV at different time points with the application of ELISA, PCR or real-time PCR. Pleconaril is known to inhibit enteroviruses and rhinoviruses but has not been explored on FMDV. Hence, the present study evaluates the in vitro antiviral efficacy of pleconaril and ribavirin on FMDV replication. The maximum non-toxic concentrations (MNTC) of pleconaril and ribavirin for BHK21 cells respectively were 7.81 μg/50 μL and 15.62 μg/50 μL. Thus, drug concentrations below MNTC were tested for their antiviral activity against serial tenfold diluted FMDV O, A and Asia 1 serotypes. Pleconaril did not inhibit FMDV serotype O replication at 7.5 μg/50 μL based on CPE inhibition assay and this was further confirmed using sandwich ELISA, PCR/real-time PCR. On the other hand, ribavirin at 15.62 μg/50 μL inhibited the in vitro replication of FMDV O, A and Asia 1 and the inhibition was confirmed by serotype specific sandwich ELISA, PCR and real-time PCR assays. The inhibition was directly proportional to the concentration of ribavirin. Therefore, ribavirin could be explored for its in vivo efficacy as a potential therapeutic in the prevention of early spread of FMDV infection in a herd.
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Affiliation(s)
- Sarkar Soumajit
- FMD Vaccine Quality Control Laboratory, ICAR-Indian Veterinary Research Institute, HA Farm (P.O), Hebbal, Bangalore, Karnataka 560 024 India
| | - Ramasamy Periyasamy Tamil Selvan
- FMD Vaccine Quality Control Laboratory, ICAR-Indian Veterinary Research Institute, HA Farm (P.O), Hebbal, Bangalore, Karnataka 560 024 India
| | - Veerakyathappa Bhanuprakash
- FMD Vaccine Quality Control Laboratory, ICAR-Indian Veterinary Research Institute, HA Farm (P.O), Hebbal, Bangalore, Karnataka 560 024 India
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15
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Kumar R, Khandelwal N, Chander Y, Riyesh T, Tripathi BN, Kashyap SK, Barua S, Maherchandani S, Kumar N. MNK1 inhibitor as an antiviral agent suppresses buffalopox virus protein synthesis. Antiviral Res 2018; 160:126-136. [DOI: 10.1016/j.antiviral.2018.10.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 11/24/2022]
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16
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Denner J. Xenotransplantation and Hepatitis E virus. Xenotransplantation 2015; 22:167-73. [PMID: 25676629 DOI: 10.1111/xen.12156] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 01/12/2015] [Indexed: 01/10/2023]
Abstract
Xenotransplantation using pig cells, tissues and organs may be associated with the transmission of porcine microorganisms to the human recipient. Some of these microorganisms may induce a zoonosis, that is an infectious disease induced by microorganisms transmitted from another species. With exception of the porcine endogenous retroviruses (PERVs), which are integrated in the genome of all pigs, the transmission of all other microorganisms can be prevented by specified or designated pathogen-free (spf or dpf, respectively) production of the animals. However, it is becoming clear in the last years that the hepatitis E virus (HEV) is one of the viruses which are difficult to eliminate. It is important to note that there are differences between HEV of genotypes (gt) 1 and gt2 on one hand and HEV of gt3 and gt4 on the other. HEV gt1 and gt2 are human viruses, and they induce hepatitis and in the worst case fatal infections in pregnant women. In contrast, HEV gt3 and gt4 are viruses of pigs, and they may infect humans, induce commonly only mild diseases, if any, and are harmless for pregnant women. The goal of this review was to evaluate the risk posed by HEV gt3 and gt4 for xenotransplantation and to indicate ways of their elimination from pigs in order to prevent transmission to the human recipient.
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De Vleeschauwer AR, Lefebvre DJ, Willems T, Paul G, Billiet A, Murao LE, Neyts J, Goris N, De Clercq K. A Refined Guinea Pig Model of Foot-and-Mouth Disease Virus Infection for Assessing the Efficacy of Antiviral Compounds. Transbound Emerg Dis 2014; 63:e205-12. [DOI: 10.1111/tbed.12255] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Indexed: 11/28/2022]
Affiliation(s)
- A. R. De Vleeschauwer
- Unit of Vesicular and Exotic Diseases; OD Viral Diseases; CODA-CERVA; Veterinary and Agrochemical Research Centre; Brussel Belgium
| | - D. J. Lefebvre
- Unit of Vesicular and Exotic Diseases; OD Viral Diseases; CODA-CERVA; Veterinary and Agrochemical Research Centre; Brussel Belgium
| | - T. Willems
- Unit of Vesicular and Exotic Diseases; OD Viral Diseases; CODA-CERVA; Veterinary and Agrochemical Research Centre; Brussel Belgium
| | - G. Paul
- MSD Animal Health; Intervet International GmbH; Köln Germany
| | | | | | - J. Neyts
- Aratana Therapeutics NV; Leuven Belgium
- Department of Microbiology and Immunology; Rega Institute for Medical Research; Katholieke Universiteit Leuven; Leuven Belgium
| | - N. Goris
- Aratana Therapeutics NV; Leuven Belgium
| | - K. De Clercq
- Unit of Vesicular and Exotic Diseases; OD Viral Diseases; CODA-CERVA; Veterinary and Agrochemical Research Centre; Brussel Belgium
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18
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Khandelwal N, Kaur G, Chaubey KK, Singh P, Sharma S, Tiwari A, Singh SV, Kumar N. Silver nanoparticles impair Peste des petits ruminants virus replication. Virus Res 2014; 190:1-7. [PMID: 24979044 DOI: 10.1016/j.virusres.2014.06.011] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 05/22/2014] [Accepted: 06/22/2014] [Indexed: 01/03/2023]
Abstract
In the present study, we evaluated the antiviral efficacy of the silver nanoparticles (SNPs) against Peste des petits ruminants virus (PPRV), a prototype Morbillivirus. The leaf extract of the Argemone maxicana was used as a reducing agent for biological synthesis of the SNPs from silver nitrate. The SNPs were characterized using UV-vis absorption spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The TEM analysis revealed particle size of 5-30 nm and the XRD analysis revealed their characteristic silver structure. The treatment of Vero cells with the SNPs at a noncytotoxic concentration significantly inhibited PPRV replication in vitro. The time-course and virus step-specific assays showed that the SNPs impair PPRV replication at the level of virus entry. The TEM analysis showed that the SNPs interact with the virion surface as well with the virion core. However, this interaction has no direct virucidal effect, instead exerts a blocking effect on viral entry into the target cells. This is the first documented evidence indicating that the SNPs are capable of inhibiting a Morbillivirus replication in vitro.
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Affiliation(s)
- Nitin Khandelwal
- School of Biotechnology, Rajiv Gandhi Technical University, Airport Road, Bhopal, Madhya Pradesh 462036, India
| | - Gurpreet Kaur
- School of Biotechnology, Rajiv Gandhi Technical University, Airport Road, Bhopal, Madhya Pradesh 462036, India
| | - Kundan Kumar Chaubey
- Virology Laboratory, Division of Animal Health, Central Institute for Research on Goats, Indian Council of Agricultural Research, Makhdoom, Mathura, Uttar Pradesh 281122, India
| | - Pushpendra Singh
- School of Biotechnology, Rajiv Gandhi Technical University, Airport Road, Bhopal, Madhya Pradesh 462036, India
| | - Shalini Sharma
- Department of Veterinary Physiology and Biochemistry, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana 125004, India
| | - Archana Tiwari
- School of Biotechnology, Rajiv Gandhi Technical University, Airport Road, Bhopal, Madhya Pradesh 462036, India
| | - Shoor Vir Singh
- Virology Laboratory, Division of Animal Health, Central Institute for Research on Goats, Indian Council of Agricultural Research, Makhdoom, Mathura, Uttar Pradesh 281122, India
| | - Naveen Kumar
- Virology Laboratory, Division of Animal Health, Central Institute for Research on Goats, Indian Council of Agricultural Research, Makhdoom, Mathura, Uttar Pradesh 281122, India.
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Kumar N, Maherchandani S, Kashyap SK, Singh SV, Sharma S, Chaubey KK, Ly H. Peste des petits ruminants virus infection of small ruminants: a comprehensive review. Viruses 2014; 6:2287-327. [PMID: 24915458 PMCID: PMC4074929 DOI: 10.3390/v6062287] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/26/2014] [Accepted: 05/28/2014] [Indexed: 12/14/2022] Open
Abstract
Peste des petits ruminants (PPR) is caused by a Morbillivirus that belongs to the family Paramyxoviridae. PPR is an acute, highly contagious and fatal disease primarily affecting goats and sheep, whereas cattle undergo sub-clinical infection. With morbidity and mortality rates that can be as high as 90%, PPR is classified as an OIE (Office International des Epizooties)-listed disease. Considering the importance of sheep and goats in the livelihood of the poor and marginal farmers in Africa and South Asia, PPR is an important concern for food security and poverty alleviation. PPR virus (PPRV) and rinderpest virus (RPV) are closely related Morbilliviruses. Rinderpest has been globally eradicated by mass vaccination. Though a live attenuated vaccine is available against PPR for immunoprophylaxis, due to its instability in subtropical climate (thermo-sensitivity), unavailability of required doses and insufficient coverage (herd immunity), the disease control program has not been a great success. Further, emerging evidence of poor cross neutralization between vaccine strain and PPRV strains currently circulating in the field has raised concerns about the protective efficacy of the existing PPR vaccines. This review summarizes the recent advancement in PPRV replication, its pathogenesis, immune response to vaccine and disease control. Attempts have also been made to highlight the current trends in understanding the host susceptibility and resistance to PPR.
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Affiliation(s)
- Naveen Kumar
- Virology Laboratory, Division of Animal Health, Central Institute for Research on Goats, Makhdoom, P.O. Farah, Mathura, UP 281122, India.
| | - Sunil Maherchandani
- Department of Veterinary Microbiology and Biotechnology, Rajasthan University of Veterinary and Animal Sciences, Bikaner, Rajasthan 334001, India.
| | - Sudhir Kumar Kashyap
- Department of Veterinary Microbiology and Biotechnology, Rajasthan University of Veterinary and Animal Sciences, Bikaner, Rajasthan 334001, India.
| | - Shoor Vir Singh
- Virology Laboratory, Division of Animal Health, Central Institute for Research on Goats, Makhdoom, P.O. Farah, Mathura, UP 281122, India.
| | - Shalini Sharma
- Department of Veterinary Physiology and Biochemistry, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana 125004, India.
| | - Kundan Kumar Chaubey
- Virology Laboratory, Division of Animal Health, Central Institute for Research on Goats, Makhdoom, P.O. Farah, Mathura, UP 281122, India.
| | - Hinh Ly
- Veterinary and Biomedical Sciences Department, University of Minnesota, 1988 Fitch Ave., Ste 295, Saint Paul, MN 55108, USA.
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20
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Potential applications for antiviral therapy and prophylaxis in bovine medicine. Anim Health Res Rev 2014; 15:102-17. [PMID: 24810855 DOI: 10.1017/s1466252314000048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Viral disease is one of the major causes of financial loss and animal suffering in today's cattle industry. Increases in global commerce and average herd size, urbanization, vertical integration within the industry and alterations in global climate patterns have allowed the spread of pathogenic viruses, or the introduction of new viral species, into regions previously free of such pathogens, creating the potential for widespread morbidity and mortality in naïve cattle populations. Despite this, no antiviral products are currently commercially licensed for use in bovine medicine, although significant progress has been made in the development of antivirals for use against bovine viral diarrhea virus (BVDV), foot and mouth disease virus (FMDV) and bovine herpesvirus (BHV). BVDV is extensively studied as a model virus for human antiviral studies. Consequently, many compounds with efficacy have been identified and a few have been successfully used to prevent infection in vivo although commercial development is still lacking. FMDV is also the subject of extensive antiviral testing due to the importance of outbreak containment for maintenance of export markets. Thirdly, BHV presents an attractive target for antiviral development due to its worldwide presence. Antiviral studies for other bovine viral pathogens are largely limited to preliminary studies. This review summarizes the current state of knowledge of antiviral compounds against several key bovine pathogens and the potential for commercial antiviral applications in the prevention and control of several selected bovine diseases.
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21
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Krol E, Pastuch-Gawolek G, Nidzworski D, Rychlowski M, Szeja W, Grynkiewicz G, Szewczyk B. Synthesis and antiviral activity of a novel glycosyl sulfoxide against classical swine fever virus. Bioorg Med Chem 2014; 22:2662-70. [DOI: 10.1016/j.bmc.2014.03.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 02/21/2014] [Accepted: 03/16/2014] [Indexed: 10/25/2022]
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22
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Osiceanu AM, Murao LE, Kollanur D, Swinnen J, De Vleeschauwer AR, Lefebvre DJ, De Clercq K, Neyts J, Goris N. In vitro surrogate models to aid in the development of antivirals for the containment of foot-and-mouth disease outbreaks. Antiviral Res 2014; 105:59-63. [PMID: 24583031 DOI: 10.1016/j.antiviral.2014.02.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/14/2014] [Accepted: 02/13/2014] [Indexed: 11/15/2022]
Abstract
Foot-and-mouth disease virus (FMDV) is a highly pathogenic member of the genus Aphthovirus (family Picornaviridae) that is only to be manipulated in high-containment facilities, thus complicating research on and discovery of antiviral strategies against the virus. Bovine rhinitis B virus (BRBV) and equine rhinitis A virus (ERAV), phylogenetically most closely related to FMDV, were explored as surrogates for FMDV in antiviral studies. Although no efficient cell culture system has been reported so far for BRBV, we demonstrate that infection of primary bovine kidney cells resulted in an extensive but rather poorly-reproducible induction of cytopathic effect (CPE). Madin-Darby bovine kidney cells on the other hand supported viral replication in the absence of CPE. Antiviral tests were developed for ERAV in Vero A cells employing a viral RNA-reduction assay and CPE-reduction assay; the latter having a Z' factor of 0.83±0.07. The BRBV and ERAV models were next used to assess the anti-aphthovirus activity of two broad-spectrum antiviral agents 2'-C-methylcytidine (2CMC) and ribavirin, as well as of the enterovirus-specific inhibitor enviroxime. The effects of the three compounds in the CPE-reduction (ERAV) and viral RNA-reduction assays (BRBV and ERAV) were comparable. Akin to 2CMC, compound A, a recently-discovered non-nucleoside pan-serotype FMDV inhibitor, also inhibited the replication of both BRBV and ERAV, whereas enviroxime was devoid of activity. The BRBV and ERAV surrogate models reported here can be manipulated in BSL-2 laboratories and may facilitate studies to unravel the mechanism of action of novel FMDV inhibitors.
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Affiliation(s)
| | | | - Denny Kollanur
- Okapi Sciences NV, Ambachtenlaan 1, 3001 Heverlee, Belgium
| | - Jan Swinnen
- Okapi Sciences NV, Ambachtenlaan 1, 3001 Heverlee, Belgium
| | - Annebel R De Vleeschauwer
- Unit of Vesicular and Exotic Diseases, Virology Department, CODA-CERVA, Veterinary and Agrochemical Research Centre, Groeselenberg 99, 1180 Brussel, Belgium
| | - David J Lefebvre
- Unit of Vesicular and Exotic Diseases, Virology Department, CODA-CERVA, Veterinary and Agrochemical Research Centre, Groeselenberg 99, 1180 Brussel, Belgium
| | - Kris De Clercq
- Unit of Vesicular and Exotic Diseases, Virology Department, CODA-CERVA, Veterinary and Agrochemical Research Centre, Groeselenberg 99, 1180 Brussel, Belgium
| | - Johan Neyts
- Okapi Sciences NV, Ambachtenlaan 1, 3001 Heverlee, Belgium; Department of Microbiology and Immunology, Rega Institute for Medical Research, University of Leuven (KU Leuven), 3000 Leuven, Belgium
| | - Nesya Goris
- Okapi Sciences NV, Ambachtenlaan 1, 3001 Heverlee, Belgium.
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Newcomer BW, Givens MD. Approved and experimental countermeasures against pestiviral diseases: Bovine viral diarrhea, classical swine fever and border disease. Antiviral Res 2013; 100:133-50. [DOI: 10.1016/j.antiviral.2013.07.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 07/01/2013] [Accepted: 07/27/2013] [Indexed: 01/13/2023]
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The potential of antiviral agents to control classical swine fever: a modelling study. Antiviral Res 2013; 99:245-50. [PMID: 23827097 DOI: 10.1016/j.antiviral.2013.06.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Revised: 06/20/2013] [Accepted: 06/21/2013] [Indexed: 11/20/2022]
Abstract
Classical swine fever (CSF) represents a continuous threat to pig populations that are free of disease without vaccination. When CSF virus is introduced, the minimal control strategy imposed by the EU is often insufficient to mitigate the epidemic. Additional measures such as preemptive culling encounter ethical objections, whereas emergency vaccination leads to prolonged export restrictions. Antiviral agents, however, provide instantaneous protection without inducing an antibody response. The use of antiviral agents to contain CSF epidemics is studied with a model describing within- and between-herd virus transmission. Epidemics are simulated in a densely populated livestock area in The Netherlands, with farms of varying sizes and pig types (finishers, piglets and sows). Our results show that vaccination and/or antiviral treatment in a 2 km radius around an infected herd is more effective than preemptive culling in a 1 km radius. However, the instantaneous but temporary protection provided by antiviral treatment is slightly less effective than the delayed but long-lasting protection offered by vaccination. Therefore, the most effective control strategy is to vaccinate animals when allowed (finishers and piglets) and to treat with antiviral agents when vaccination is prohibited (sows). As independent control measure, antiviral treatment in a 1 km radius presents an elevated risk of epidemics running out of control. A 2 km control radius largely eliminates this risk.
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Lefebvre DJ, De Vleeschauwer AR, Goris N, Kollanur D, Billiet A, Murao L, Neyts J, De Clercq K. Proof of concept for the inhibition of foot-and-mouth disease virus replication by the anti-viral drug 2'-C-methylcytidine in severe combined immunodeficient mice. Transbound Emerg Dis 2013; 61:e89-91. [PMID: 23480064 DOI: 10.1111/tbed.12069] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Indexed: 11/30/2022]
Abstract
Recent European contingency plans envisage emergency vaccination as an animal-friendly control strategy for foot-and-mouth disease (FMD). Anti-viral drugs may be used as an alternative or complementary measure. We here demonstrate that the nucleoside analogue 2'-C-methylcytidine (2'CMC) protects severe combined immunodeficient (SCID) mice against lethal FMD virus infection. In brief, SCID mice were inoculated with serotype A FMD virus and treated for five consecutive days with 2'CMC. All 15 treated mice remained healthy until the end of the study at 14 days post-infection (dpi). At that time, viral RNA was no longer detected in 13 of 15 treated mice. All eight untreated mice suffered from an acute generalized disease and were euthanized for ethical reasons on average at 4 dpi. These results illustrate the potential of small molecules to control FMD.
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Affiliation(s)
- D J Lefebvre
- Unit of Vesicular and Exotic Diseases, Virology Department, CODA-CERVA, Veterinary and Agrochemical Research Centre, Brussel, Belgium
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Ribbens S, Goris N, Neyts J, Dewulf J. Classical swine fever outbreak containment using antiviral supplementation: A potential alternative to emergency vaccination and stamping-out. Prev Vet Med 2012; 106:34-41. [DOI: 10.1016/j.prevetmed.2012.03.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Revised: 02/27/2012] [Accepted: 03/03/2012] [Indexed: 11/29/2022]
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Kibenge FS, Godoy MG, Fast M, Workenhe S, Kibenge MJ. Countermeasures against viral diseases of farmed fish. Antiviral Res 2012; 95:257-81. [DOI: 10.1016/j.antiviral.2012.06.003] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Revised: 06/01/2012] [Accepted: 06/09/2012] [Indexed: 12/24/2022]
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28
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Inhibition of viral RNA synthesis in canine distemper virus infection by proanthocyanidin A2. Antiviral Res 2011; 92:447-52. [DOI: 10.1016/j.antiviral.2011.10.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 08/22/2011] [Accepted: 10/06/2011] [Indexed: 02/02/2023]
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29
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Diagnostic performance and application of two commercial cell viability assays in foot-and-mouth disease research. J Virol Methods 2011; 173:108-14. [PMID: 21295609 DOI: 10.1016/j.jviromet.2011.01.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 01/10/2011] [Accepted: 01/25/2011] [Indexed: 11/21/2022]
Abstract
Cell-based assays are still used widely in foot-and-mouth disease (FMD) research, despite the existence of a wide variety of molecular techniques. The aim of this study was to validate an automated, quantitative spectrometric reading to replace the time-consuming and subjective microscopic (MIC) evaluation of the FMD virus-induced cytopathic effect (CPE). Therefore, the diagnostic performance of two commercial cell viability assays (CellTiter 96(®) AQueous One Solution Cell Proliferation Assay (MTS) and CellTiter-Blue(®) Cell Viability Assay (CTB), both from Promega, Leiden, The Netherlands) was evaluated. Following optimization of the assay protocols and using the MIC results as a reference standard, the absorbance-read MTS assay, the fluorescence-read CTB assay and the absorbance-read CTB (CTB(abs)) assay demonstrated similar high sensitivities (97%, 99% and 98%, respectively), specificities (100%, 98% and 99%, respectively), accuracy measures (0.99, 0.98 and 0.98, respectively), precision measures (1.00, 0.98 and 0.99, respectively) and Cohen kappa agreement indices (0.97, 0.97 and 0.96, respectively) for detecting CPE in cell cultures. Due to its performance, cost effectiveness and ease of use, the CTB(abs) assay was selected for further evaluation of its ability to detect virus neutralization and to screen antiviral compounds. The CTB(abs) assay had 99% sensitivity and 100% specificity for the detection of neutralizing antibodies in sera from cattle infected with FMDV and in sera from unvaccinated, uninfected cattle and resulted in a mean Z'-factor of 0.85 for antiviral compound test plates. The CTB(abs) assay is now used routinely in the Belgian FMD reference laboratory for serological testing and high-throughput antiviral compound screening.
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Lefebvre DJ, Neyts J, De Clercq K. Development of a Foot-and-Mouth Disease Infection Model in Severe Combined Immunodeficient Mice for the Preliminary Evaluation of Antiviral Drugs. Transbound Emerg Dis 2010; 57:430-3. [DOI: 10.1111/j.1865-1682.2010.01169.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Vrancken R, Haegeman A, Dewulf J, Paeshuyse J, Puerstinger G, Tignon M, Le Potier MF, Neyts J, Koenen F. The reduction of CSFV transmission to untreated pigs by the pestivirus inhibitor BPIP: a proof of concept. Vet Microbiol 2009; 139:365-8. [PMID: 19592179 DOI: 10.1016/j.vetmic.2009.06.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 06/03/2009] [Accepted: 06/12/2009] [Indexed: 11/26/2022]
Abstract
5-[(4-Bromophenyl)methyl]-2-phenyl-5H-imidazo[4,5-c]pyridine (BPIP) is a representative molecule of a novel class of highly active in vitro inhibitors of the replication of Classical swine fever virus (CSFV). We recently demonstrated in a proof of concept study that the molecule has a marked effect on viral replication in CSFV-infected pigs. Here, the effect of antiviral treatment on virus transmission to untreated sentinel pigs was studied. Therefore, BPIP-treated pigs (n=4), intra-muscularly infected with CSFV, were placed into contact with untreated sentinel pigs (n=4). Efficient transmission of CSFV from four untreated seeder pigs to four untreated sentinels was observed. In contrast, only two out of four sentinel animals in contact with BPIP-treated seeder animals developed a short transient infection, of which one was likely the result of sentinel to sentinel transmission. A significant lower viral genome load was measured in tonsils of sentinels in contact with BPIP-treated seeder animals compared to the positive control group (p=0.015). Although no significant difference (p=0.126) in the time of onset of viraemia could be detected between the groups of contact animals, a tendency towards the reduction of virus transmission was observed. Since sentinel animals were left untreated in this exploratory trial, the study can be regarded as a worst case scenario and gives therefore an underestimation of the potential efficacy of the activity of BPIP on virus transmission.
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Affiliation(s)
- R Vrancken
- Veterinary and Agrochemical Research Centre, Groeselenberg 99, B-1180 Ukkel, Belgium.
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Goris N, Vandenbussche F, Herr C, Villers J, Van der Stede Y, De Clercq K. Validation of two real-time RT-PCR methods for foot-and-mouth disease diagnosis: RNA-extraction, matrix effect, uncertainty of measurement and precision. J Virol Methods 2009; 160:157-62. [PMID: 19447138 DOI: 10.1016/j.jviromet.2009.05.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Revised: 05/03/2009] [Accepted: 05/06/2009] [Indexed: 11/30/2022]
Abstract
Real-time reverse transcription polymerase chain reaction (rRT-PCR) assays are being used routinely for diagnosing foot-and-mouth disease virus (FMDV). Although most laboratories determine analytical and diagnostic sensitivity and specificity, a thorough validation in terms of establishing optimal RNA-extraction conditions, matrix effect, uncertainty of measurement and precision is not performed or reported generally. In this study, different RNA-extraction procedures were compared for two FMDV rRT-PCRs. The NucleoSpin columns available commercially combined high extraction efficiency with ease-of-automation. Furthermore, six different FMDV-negative matrices were spiked with a dilution series of FMDV SAT1 ZIM 25/89. Compared to cell-culture-spiked viral control samples, no matrix effect on the analytical sensitivity was found for blood or foot epithelium. Approximately 1log(10) reduction in detection limit was noted for faecal and tongue epithelium samples, whereas a 3log(10) decrease was observed for spleen samples. By testing the same dilution series in duplicate on 10 different occasions, an estimation of uncertainty of measurement and precision was obtained using blood as matrix. Both rRT-PCRs produced highly precise results emphasising their potential to replace conventional virological methods. The uncertainty measurement, as described in this study, proved to be a useful tool to evaluate the probability of making a wrong decision.
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Affiliation(s)
- Nesya Goris
- Veterinary and Agrochemical Research Centre, Virology Department, Brussels, Belgium.
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Bhanuprakash V, Indrani BK, Hosamani M, Balamurugan V, Singh RK. Bluetongue vaccines: the past, present and future. Expert Rev Vaccines 2009; 8:191-204. [PMID: 19196199 DOI: 10.1586/14760584.8.2.191] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Bluetongue (BT) is a noncontagious and arboviral disease of both domestic and wild ruminants. The disease is enzootic in areas where reservoirs (cattle and wild ruminants) and vectors exist for the BT virus (BTV). A total of 24 BTV serotypes have been recognized worldwide. The major control measures include restriction of animal movement, vector control applying insecticides, slaughter of infected animals and vaccination. Prophylactic immunization of sheep against BT is the most practical and effective control measure to combat BT infection. At present, attenuated vaccines are used in the Republic of South Africa, the USA and other countries. However, EU countries were using attenuated vaccines, only recently shifting to inactivated vaccines owing to their safety and efficacy. In India, inactivated vaccines are in experimental stages and are expected to be on the market shortly. Inactivated vaccines generate serotype-specific long-lasting protective immunity after two injections, and may help in controlling epidemics. Differentiating infected from vaccinated animals (DIVA) is theoretically possible with inactivated vaccines but has not yet been developed, whereas the attenuated live vaccines are not candidates for DIVA. Attenuated live vaccines are efficacious but safety issues are of great concern. New-generation vaccines (subunit, virus-like particles, core-like particles and vectored) can be employed for DIVA. Recombinant vaccines, which generate cross-protection against multiple BTV serotypes, have great potential in BT vaccine regimens. Furthermore, new-generation vaccines are safe and efficacious experimentally, but large-scale field trials are warranted. Alternative areas, such as antivirals, siRNA, interferon and nanotechnology, may be of future use in the control of BT. We give an overview of BT vaccines, starting from conventional to recent developments, and their feasibility in controlling BT infection.
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Affiliation(s)
- V Bhanuprakash
- Division of Virology, Indian Veterinary Research Institute, Campus Mukteswar-263 138, Nainital, Uttarakhand, India.
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Passive immunization with llama single-domain antibody fragments reduces foot-and-mouth disease transmission between pigs. Vaccine 2009; 27:1904-11. [PMID: 19368770 DOI: 10.1016/j.vaccine.2009.01.110] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 01/21/2009] [Accepted: 01/22/2009] [Indexed: 01/24/2023]
Abstract
We aim to develop a method that confers rapid protection against foot-and-mouth disease (FMD) by passive immunization with recombinant llama single-domain antibody fragments (VHHs). Previously constructed genetic fusions of two VHHs (VHH2s) that either neutralizes FMDV or binds to porcine immunoglobulin to increase the serum half-life, conferred only limited protection to pigs. We therefore now generated VHH3s containing an additional FMDV binding VHH. Two VHH3s neutralized FMDV more potently than single VHHs and were highly produced by yeast cells. Injection of a mixture of these two VHH3s 24h before FMD challenge infection of pigs reduced and delayed the development of clinical disease, viraemia and viral shedding. Furthermore, it significantly (P=0.023) delayed FMD transmission. Thus, we have shown a proof of concept of passive FMD immunoprophylaxis using VHHs.
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Passive immunization of pigs with bispecific llama single-domain antibody fragments against foot-and-mouth disease and porcine immunoglobulin. Vet Microbiol 2008; 132:56-64. [DOI: 10.1016/j.vetmic.2008.04.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2007] [Revised: 04/10/2008] [Accepted: 04/23/2008] [Indexed: 11/23/2022]
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Goris N, Maradei E, D’Aloia R, Fondevila N, Mattion N, Perez A, Smitsaart E, Nauwynck H, La Torre J, Palma E, De Clercq K. Foot-and-mouth disease vaccine potency testing in cattle using homologous and heterologous challenge strains: Precision of the “Protection against Podal Generalisation” test. Vaccine 2008; 26:3432-7. [DOI: 10.1016/j.vaccine.2008.04.034] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Revised: 04/08/2008] [Accepted: 04/15/2008] [Indexed: 10/22/2022]
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Leyssen P, De Clercq E, Neyts J. Molecular strategies to inhibit the replication of RNA viruses. Antiviral Res 2008; 78:9-25. [PMID: 18313769 PMCID: PMC7114363 DOI: 10.1016/j.antiviral.2008.01.004] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 01/04/2008] [Accepted: 01/08/2008] [Indexed: 12/24/2022]
Abstract
There are virtually no antiviral drugs available for the treatment of infections with RNA viruses. This is particularly worrisome since most of the highly pathogenic and emerging viruses are, and will likely continue to be, RNA viruses. These viruses can cause acute, severe illness, including severe respiratory disease, hemorrhagic fever and encephalitis, with a high case fatality rate. It is important to have potent and safe drugs at hand that can be used for the treatment or prophylaxis of such infections. Drugs approved for the treatment of RNA virus infections (other than HIV) are the influenza M2 channel inhibitors, amantadine and rimantadine; the influenza neuraminidase inhibitors, oseltamivir and zanamivir, and ribavirin for the treatment of infections with respiratory syncytial virus and hepatitis C virus. The molecular mechanism(s) by which ribavirin inhibits viral replication, such as depletion of intracellular GTP pools and induction of error catastrophe, may not readily allow the design of analogues that are more potent/selective than the parent drug. Highly pathogenic RNA viruses belong to a variety of virus families, each having a particular replication strategy, thus offering a wealth of potential targets to selectively inhibit viral replication. We here provide a non-exhaustive review of potential experimental strategies, using small molecules, to inhibit the replication of several RNA viruses. Other approaches, such as the use of interferon or other host-response modifiers, immune serum or neutralizing antibodies, are not addressed in this review.
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Affiliation(s)
| | | | - Johan Neyts
- Rega Institute for Medical Research, Catholic University Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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Highly pathogenic RNA viral infections: Challenges for antiviral research. Antiviral Res 2008; 78:1-8. [DOI: 10.1016/j.antiviral.2007.12.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Revised: 12/12/2007] [Accepted: 12/13/2007] [Indexed: 12/23/2022]
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