1
|
Maikhunthod B, Chaipayang S, Jittmittraphap A, Thippornchai N, Boonchuen P, Tittabutr P, Eumkeb G, Sabuakham S, Rungrotmongkol T, Mahalapbutr P, Leaungwutiwong P, Teaumroong N, Tanthanuch W. Exploring the therapeutic potential of Thai medicinal plants: in vitro screening and in silico docking of phytoconstituents for novel anti-SARS-CoV-2 agents. BMC Complement Med Ther 2024; 24:274. [PMID: 39030504 DOI: 10.1186/s12906-024-04586-z] [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: 11/04/2023] [Accepted: 07/10/2024] [Indexed: 07/21/2024] Open
Abstract
BACKGROUND The high virulence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for coronavirus disease 2019 (COVID-19), has triggered global health and economic concerns. The absence of specific antiviral treatments and the side effects of repurposed drugs present persistent challenges. This study explored a promising antiviral herbal extract against SARS-CoV-2 from selected Thai medicinal plants based on in vitro efficacy and evaluated its antiviral lead compounds by molecular docking. METHODS Twenty-two different ethanolic-aqueous crude extracts (CEs) were rapidly screened for their potential activity against porcine epidemic diarrhea virus (PEDV) as a surrogate using a plaque reduction assay. Extracts achieving ≥ 70% anti-PEDV efficacy proceeded to the anti-SARS-CoV-2 activity test using a 50% tissue culture infectious dose method in Vero E6 cells. Molnupiravir and extract-free media served as positive and negative controls, respectively. Potent CEs underwent water/ethyl acetate fractionation to enhance antiviral efficacy, and the fractions were tested for anti-SARS-CoV-2 performance. The fraction with the highest antiviral potency was identified using liquid chromatography-high-resolution mass spectrometry (LC-HRMS). Molecular docking analyses of these compounds against the main protease (Mpro) of SARS-CoV-2 (6LU7) were performed to identify antiviral lead molecules. The top three hits were further evaluated for their conformational stability in the docked complex using molecular dynamics (MD) simulation. RESULTS The water fraction of mulberry (Morus alba Linn.) leaf CE (WF-MLCE) exhibited the most potent anti-SARS-CoV-2 efficacy with low cytotoxicity profile (CC50 of ~ 0.7 mg/mL), achieving 99.92% in pre-entry mode and 99.88% in postinfection treatment mode at 0.25 mg/mL. Flavonoids and conjugates were the predominant compounds identified in WF-MLCE. Molecular docking scores of several flavonoids against SARS-CoV-2 Mpro demonstrated their superior antiviral potency compared to molnupiravir. Remarkably, myricetin-3-O-β-D-galactopyranoside, maragrol B, and quercetin 3-O-robinobioside exhibited binding energies of ~ - 9 kcal/mol. The stability of each ligand-protein complex of these compounds with the Mpro system showed stability during MD simulation. These three molecules were pronounced as antiviral leads of WF-MLCE. Given the low cytotoxicity and high antiviral potency of WF-MLCE, it holds promise as a candidate for future therapeutic development for COVID-19 treatment, especially considering its economic and pharmacological advantages.
Collapse
Affiliation(s)
- Bussayarat Maikhunthod
- School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Sukanya Chaipayang
- Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000, Thailand
| | - Akanitt Jittmittraphap
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Narin Thippornchai
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Pakpoom Boonchuen
- School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Panlada Tittabutr
- School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Griangsak Eumkeb
- School of Preclinical Sciences, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Sahachai Sabuakham
- Department of Biochemistry, Center for Translational Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Thanyada Rungrotmongkol
- Program in Bioinformatics and Computational Biology, Graduate School, Chulalongkorn University, Bangkok, 10330, Thailand
- Center of Excellence in Structural and Computational Biology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Panupong Mahalapbutr
- Department of Biochemistry, Center for Translational Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Pornsawan Leaungwutiwong
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Neung Teaumroong
- School of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand.
| | - Waraporn Tanthanuch
- Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000, Thailand.
| |
Collapse
|
2
|
Padhi AK, Kalita P, Maurya S, Poluri KM, Tripathi T. From De Novo Design to Redesign: Harnessing Computational Protein Design for Understanding SARS-CoV-2 Molecular Mechanisms and Developing Therapeutics. J Phys Chem B 2023; 127:8717-8735. [PMID: 37815479 DOI: 10.1021/acs.jpcb.3c04542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
The continuous emergence of novel SARS-CoV-2 variants and subvariants serves as compelling evidence that COVID-19 is an ongoing concern. The swift, well-coordinated response to the pandemic highlights how technological advancements can accelerate the detection, monitoring, and treatment of the disease. Robust surveillance systems have been established to understand the clinical characteristics of new variants, although the unpredictable nature of these variants presents significant challenges. Some variants have shown resistance to current treatments, but innovative technologies like computational protein design (CPD) offer promising solutions and versatile therapeutics against SARS-CoV-2. Advances in computing power, coupled with open-source platforms like AlphaFold and RFdiffusion (employing deep neural network and diffusion generative models), among many others, have accelerated the design of protein therapeutics with precise structures and intended functions. CPD has played a pivotal role in developing peptide inhibitors, mini proteins, protein mimics, decoy receptors, nanobodies, monoclonal antibodies, identifying drug-resistance mutations, and even redesigning native SARS-CoV-2 proteins. Pending regulatory approval, these designed therapies hold the potential for a lasting impact on human health and sustainability. As SARS-CoV-2 continues to evolve, use of such technologies enables the ongoing development of alternative strategies, thus equipping us for the "New Normal".
Collapse
Affiliation(s)
- Aditya K Padhi
- Laboratory for Computational Biology & Biomolecular Design, School of Biochemical Engineering, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India
| | - Parismita Kalita
- Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Shillong 793022, India
| | - Shweata Maurya
- Laboratory for Computational Biology & Biomolecular Design, School of Biochemical Engineering, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India
| | - Krishna Mohan Poluri
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
- Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
| | - Timir Tripathi
- Molecular and Structural Biophysics Laboratory, Department of Biochemistry, North-Eastern Hill University, Shillong 793022, India
- Department of Zoology, School of Life Sciences, North-Eastern Hill University, Shillong 793022, India
| |
Collapse
|
3
|
Porcine Enteric Coronavirus Infections in Wild Boar in Poland - a Pilot Study. J Vet Res 2021; 65:265-269. [PMID: 34917837 PMCID: PMC8643093 DOI: 10.2478/jvetres-2021-0041] [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: 02/16/2021] [Accepted: 07/01/2021] [Indexed: 11/21/2022] Open
Abstract
Introduction Porcine epidemic diarrhoea virus (PEDV) of the Coronaviridae family causes significant economic losses in the pig industry worldwide. Wild boars contribute to the transmission of different viral, bacterial and parasitic infections to livestock animals and humans. However, their role in the maintenance and transmission of PEDV has not been established. Material and Methods In this study, blood and faecal samples from 157 wild boars were collected from 14 provinces of Poland during the 2017–2018 hunting season. RNA was extracted from the faecal homogenate supernatant and subjected to quantitative RT-PCR (RT-qPCR), while clotted blood samples were used for detection of antibodies against PEDV by ELISA. Results Five blood samples (3.2%) were seropositive in ELISA, while none of the faecal samples were found positive using RT-qPCR assays. Conclusion The results of this analysis indicate the need for additional studies incorporating a larger number of samples and preferably comparing different serological methods, to confirm whether wild boars in Poland act as PEDV reservoirs.
Collapse
|
4
|
Singh G, Jorgenson J, Pringle T, Nelson T, Ramamoorthy S. Monitoring SARS-CoV-2 decontamination by dry heat and ultraviolet treatment with a swine coronavirus as a surrogate. Infect Prev Pract 2021; 3:100103. [PMID: 34316570 PMCID: PMC7694467 DOI: 10.1016/j.infpip.2020.100103] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/18/2020] [Indexed: 01/17/2023] Open
Abstract
The critical need for reliable methods to validate decontamination protocols for personal protective equipment (PPE) for re-use during the SARS-CoV-2 pandemic is limited by the need for specialized containment facilities to handle the virus. Hence, we have herein validated the use of a swine coronavirus as a surrogate, and tested the effectiveness of dry heat and ultraviolet (UV) rays for PPE decontamination. Exposure of experimentally contaminated N95 masks and hospital gowns to 60°C for 20 min, and UVC at 1800 mJ/cm2 resulted in a 4-log reduction and inactivation of the surrogate virus. This study provides a novel alternative to validate PPE reprocessing methods.
Collapse
Affiliation(s)
- G Singh
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, USA
| | - J Jorgenson
- Blue Water Resolute (BWR) Innovations, Fargo, ND, USA
| | | | - T Nelson
- Blue Water Resolute (BWR) Innovations, Fargo, ND, USA
| | - S Ramamoorthy
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, USA
| |
Collapse
|
5
|
Srijangwad A, Tripipat T, Saeng-Chuto K, Jermsujarit P, Tantituvanont A, Okabayashi T, Nilubol D. Development and validation of indirect ELISA for antibody detection against different protein antigens of porcine epidemic diarrhea virus in the colostrum and milk of sows. J Immunol Methods 2021; 494:113045. [PMID: 33781786 DOI: 10.1016/j.jim.2021.113045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/20/2021] [Accepted: 03/20/2021] [Indexed: 11/29/2022]
Abstract
The objectives of this study are to develop and optimize indirect ELISA based on three coating antigens of porcine epidemic diarrhea virus (PEDV), recombinant spike (S12), nucleocapsid (N), and whole viral (WV) proteins, for the detection of IgG and IgA antibodies in colostrum and milk and to evaluate the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the assay as a diagnostic method. Colostrum (n = 347) and milk (n = 272) samples from sows were employed in this assay. Indirect ELISA based on three coating antigens was assessed by receiver operating characteristic (ROC) curve analysis with a virus neutralization (VN) test as a reference method, and the cutoff value for calculating DSe and DSp was determined. S12-ELISA showed higher DSe and DSp of IgG and IgA detection compared to N- and WV-ELISA in both colostrum and milk samples. Moreover, S12-ELISA showed perfect agreement and a high correlation with the VN test, which was better than the N- and WV-ELISA for both IgG and IgA detection in colostrum and milk. In contrast, N-ELISA showed lower DSe and DSp compared to S12- and WV-ELISA, along with a correlation with VN and substantial agreement with the VN test. Nevertheless, our developed ELISAs have accuracy for repeatability in both inter- and intra-assay variation. Overall, this research demonstrates that S12-ELISA is more suitable than WV- and N-ELISA to detect IgG and IgA antibodies against PEDV from both colostrum and milk samples.
Collapse
Affiliation(s)
- Anchalee Srijangwad
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Thitima Tripipat
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Kepalee Saeng-Chuto
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Patumporn Jermsujarit
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Angkana Tantituvanont
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand
| | - Tamaki Okabayashi
- Department of Veterinary Science, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan
| | - Dachrit Nilubol
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
| |
Collapse
|
6
|
Myint O, Yoshida A, Sekiguchi S, Van Diep N, Fuke N, Izzati UZ, Hirai T, Yamaguchi R. Development of indirect enzyme-linked immunosorbent assay for detection of porcine epidemic diarrhea virus specific antibodies (IgG) in serum of naturally infected pigs. BMC Vet Res 2019; 15:409. [PMID: 31718620 PMCID: PMC6852973 DOI: 10.1186/s12917-019-2123-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 10/09/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Porcine epidemic diarrhea virus (PEDV) infection is a highly contagious infectious disease causing watery diarrhea, vomiting, dehydration and high mortality rate in newborn piglets. PEDV infection can cause high economic losses in pig industry. In Japan, a PEDV outbreak occurred with high mortality from 2013 to 2015. Even though until now, PEDV infection occurs sporadically. For the control and monitoring of PEDV infection, not only symptomatic pigs, but also asymptomatic pigs should be identified. The objective of this study is to develop and optimize novel indirect ELISA as a simple, rapid, sensitive and specific method for the detection of anti-PEDV antibodies and evaluate the efficacy of the assay as a diagnostic method for PED. RESULTS One hundred sixty-two serum samples, consisting of 81 neutralization test (NT) positive and 81 NT negative sera, were applied to the assay. Indirect ELISA test based on whole virus antigen (NK94P6 strain) derived from Vero cell culture was evaluated by receiver operating characteristic (ROC) analysis with neutralization test (NT) as a reference method, and cut-off value was determined as 0.320 with sensitivity and specificity of 92.6 and 90.1%, respectively. The area under curve (AUC) was 0.949, indicating excellent accuracy of indirect ELISA test. There was significant positive correlation between indirect ELISA and neutralization test (R = 0.815, P < 0.05). Furthermore, the kappa statics showed the excellent agreement between these two tests (kappa value = 0.815). In addition, the sensitivity and specificity of preserved plates with different periods (1 day, 2 weeks, 1, 2, 3, 4, 5 and 6 months) after drying antigen coated plates were 100% and 80-100%, respectively. CONCLUSIONS The developed indirect ELISA test in our study would be useful as a reliable test for serological survey and disease control of PEDV infection, and our pre-antigen coated ELISA plates can be preserved at 4 °C until at least 6 months.
Collapse
Affiliation(s)
- Ohnmar Myint
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-Nishi, Miyazaki, 889-2192, Japan
| | - Ayako Yoshida
- Department of Veterinary Parasitic Diseases, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan.,Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan
| | - Satoshi Sekiguchi
- Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan.,Department of Animal Infectious Disease and Prevention, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Nguyen Van Diep
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-Nishi, Miyazaki, 889-2192, Japan
| | - Naoyuki Fuke
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-Nishi, Miyazaki, 889-2192, Japan
| | - Uda Zahli Izzati
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-Nishi, Miyazaki, 889-2192, Japan
| | - Takuya Hirai
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-Nishi, Miyazaki, 889-2192, Japan
| | - Ryoji Yamaguchi
- Department of Veterinary Pathology, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-Nishi, Miyazaki, 889-2192, Japan.
| |
Collapse
|
7
|
Singh G, Singh P, Pillatzki A, Nelson E, Webb B, Dillberger-Lawson S, Ramamoorthy S. A Minimally Replicative Vaccine Protects Vaccinated Piglets Against Challenge With the Porcine Epidemic Diarrhea Virus. Front Vet Sci 2019; 6:347. [PMID: 31696121 PMCID: PMC6817509 DOI: 10.3389/fvets.2019.00347] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 09/24/2019] [Indexed: 11/24/2022] Open
Abstract
Porcine epidemic diarrhea virus (PEDV), is an economically important enteric coronavirus, with over a 90% mortality rate in neonatal piglets. The virus emerged in the US in 2013, resulting in severe production losses. Effective vaccine development against PEDV is a challenge. Inactivated vaccines are of questionable efficacy. Attenuated vaccines, while more effective, require a relatively long lead development time, are associated with safety concerns and are also unable to prevent new field outbreaks. To combine the safety and efficacy advantages of inactivated and attenuated PEDV vaccines, respectively, in this study, we tested the hypothesis that subjecting PEDV virions to heat treatment at 44°C for 10 min to reversibly unfold structural proteins, followed by exposure to RNAse to fragment the genome, would result in a vaccine preparation with intact viral structure/antigenicity but highly diminished replicative abilities. We expected the vaccine to be both safe and effective in a piglet challenge model. Following the heat and RNAse treatment, PEDV virions had an intact electron microscopic ultrastructure and were amplified only in the 3rd passage in Vero cells, indicating that diminished replication was achieved in vitro. Strong PEDV spike-protein specific and virus neutralizing antibody responses were elicited in vaccinated piglets. Upon challenge, all vaccinated pigs were protected against fecal viral shedding and intestinal pathology, while the unvaccinated controls were not. The vaccine virus was not detected in the fecal matter of vaccinated pigs prior to challenge; nor did they develop intestinal lesions. Thus, the described approach has significant promise in improving current approaches for PEDV immunization.
Collapse
Affiliation(s)
- Gagandeep Singh
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, United States
| | - Pankaj Singh
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, United States
| | - Angela Pillatzki
- Animal Disease Research and Diagnostic Laboratory, South Dakota State University, Brookings, SD, United States
| | - Eric Nelson
- Animal Disease Research and Diagnostic Laboratory, South Dakota State University, Brookings, SD, United States
| | - Brett Webb
- Veterinary Diagnostic Laboratory, North Dakota State University, Fargo, ND, United States
| | - Steven Dillberger-Lawson
- Animal Disease Research and Diagnostic Laboratory, South Dakota State University, Brookings, SD, United States
| | - Sheela Ramamoorthy
- Department of Microbiological Sciences, North Dakota State University, Fargo, ND, United States
| |
Collapse
|
8
|
Xie W, Ao C, Yang Y, Liu Y, Liang R, Zeng Z, Ye G, Xiao S, Fu ZF, Dong W, Peng G. Two critical N-terminal epitopes of the nucleocapsid protein contribute to the cross-reactivity between porcine epidemic diarrhea virus and porcine transmissible gastroenteritis virus. J Gen Virol 2019; 100:206-216. [PMID: 30652967 DOI: 10.1099/jgv.0.001216] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Both porcine epidemic diarrhoea virus (PEDV) and porcine transmissible gastroenteritis virus (TGEV), which cause high mortality in piglets and produce similar clinical symptoms and histopathological morphology, belong to the genus Alphacoronavirus. Serological diagnosis plays an important role in distinguishing pathogen species. Together with the spike (S) protein, the nucleocapsid (N) protein is one of the immunodominant regions among coronaviruses. In this study, two-way antigenic cross-reactivity between the N proteins of PEDV and TGEV was observed by indirect immunofluorescence assay (IFA) and Western blot analysis. Furthermore, the PEDV N protein harbouring truncations of amino acids (aa) 1 to 170 or aa 125 to 301 was demonstrated to cross-react with the anti-TGEV N polyclonal antibody (PAb), whereas the truncation-expressing aa 302 to 401 resulted in a specific reaction with the anti-PEDV N PAb but not with the anti-TGEV N PAb. Mutants of the PEDV N protein were generated based on sequence alignment and structural analysis; we then confirmed that the N-terminal residues 58-RWRMRRGERIE-68 and 78-LGTGPHAD-85 contributed to the cross-reactivity. All the results provide vital clues for the development of precise diagnostic assays for porcine coronaviruses.
Collapse
Affiliation(s)
- Wenting Xie
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Chaojie Ao
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Yilin Yang
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Yinan Liu
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Rui Liang
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Zhe Zeng
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Gang Ye
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Shaobo Xiao
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Zhen F Fu
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 4Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Wanyu Dong
- 5National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
| | - Guiqing Peng
- 3The Cooperative Innovation Center for Sustainable Pig Production, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 2College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, PR China
- 1State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei, PR China
| |
Collapse
|
9
|
A convenient colorimetric assay for the quantification of porcine epidemic diarrhea virus and neutralizing antibodies. J Virol Methods 2018; 262:32-37. [PMID: 30218684 PMCID: PMC7113882 DOI: 10.1016/j.jviromet.2018.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 09/02/2018] [Accepted: 09/09/2018] [Indexed: 01/06/2023]
Abstract
PEDV is an economically important, enteric coronavirus of swine. Visual reading of 96 well plates for virus neutralization (V/N) or TCID50 assays is time consuming. The newly developed colorimetric PEDV V/N and TCID50 assays are reliable and convenient.
Neonatal enteritis caused by the porcine epidemic diarrhea virus (PEDV) is an important cause of high mortality and economic losses to the swine industry. Virus neutralization (V/N) assays are commonly requested in diagnostic laboratories for the assessment of protective antibodies. However, the visual assessment of viral cytopathic effects by operators to determine antibody titers or for viral quantification is a tedious, subjective and time-consuming process, especially when high volume testing is involved. To improve the ease of testing, a colorimetric virus neutralization and TCID50 assays were developed and validated in this study using (3-(4,5-dimethylthiazol-2-yl) Tr-2,5-diphenyltetrazolium- bromide) (MTT), a colorimetric agent which measures cell viability. The respective conventional assays were used as the gold standards. An OD cut off value of ≤0.53, selected by receiver operating characteristics analysis, could distinguish between wells with and without CPE accurately. Performance and reproducibility parameters of the colorimetric assays were comparable to the conventional assays. The described methods can reduce testing time in diagnostic laboratories, while significantly improving current protocols.
Collapse
|
10
|
Reactivity of Porcine Epidemic Diarrhea Virus Structural Proteins to Antibodies against Porcine Enteric Coronaviruses: Diagnostic Implications. J Clin Microbiol 2017; 55:1426-1436. [PMID: 28202790 DOI: 10.1128/jcm.02507-16] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 02/10/2017] [Indexed: 12/25/2022] Open
Abstract
The development of porcine epidemic diarrhea virus (PEDV) antibody-based assays is important for detecting infected animals, confirming previous virus exposure, and monitoring sow herd immunity. However, the potential cross-reactivity among porcine coronaviruses is a major concern for the development of pathogen-specific assays. In this study, we used serum samples (n = 792) from pigs of precisely known infection status and a multiplex fluorescent microbead-based immunoassay and/or enzyme-linked immunoassay platform to characterize the antibody response to PEDV whole-virus (WV) particles and recombinant polypeptides derived from the four PEDV structural proteins, i.e., spike (S), nucleocapsid (N), membrane (M), and envelope (E). Antibody assay cutoff values were selected to provide 100% diagnostic specificity for each target. The earliest IgG antibody response, mainly directed against S1 polypeptides, was observed at days 7 to 10 postinfection. With the exception of nonreactive protein E, we observed similar antibody ontogenies and patterns of seroconversion for S1, N, M, and WV antigens. Recombinant S1 provided the best diagnostic sensitivity, regardless of the PEDV strain, with no cross-reactivity detected against transmissible gastroenteritis virus (TGEV), porcine respiratory coronavirus (PRCV), or porcine deltacoronavirus (PDCoV) pig antisera. The WV particles showed some cross-reactivity to TGEV Miller and TGEV Purdue antisera, while N protein presented some cross-reactivity to TGEV Miller. The M protein was highly cross-reactive to TGEV and PRCV antisera. Differences in the antibody responses to specific PEDV structural proteins have important implications in the development and performance of antibody assays for the diagnosis of PEDV enteric disease.
Collapse
|