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1.
Zhongguo Yufang Shouyi Xuebao / Chinese Journal of Preventive Veterinary Medicine ; 44(11):1135-1141, 2023.
Article in Chinese | CAB Abstracts | ID: covidwho-20238997

ABSTRACT

Previous studies have revealed that developmental regulated brain protein (Drebrin) is involved in cell- to-cell communication, nerve transmission, tumor metastasis, spermatogenesis and other life activities, but there are few studies on viruses. The aim of the current research was therefore, to study the function of Drebrin and its effect on the proliferation of porcine epidemic diarrhea virus (PEDV). The Drebrin gene was cloned according to the Drebrin gene sequence (XM_008015438.2) of Chlorocebus sabaeus registered by GenBank, and the phylogenetic tree was constructed to analyze its homology. The results showed that the CDS region of Vero cells Drebrin gene was 2088 bp long, encoding 695 amino acids, and was relatively conserved and had high homology with all species. To investigate the effect of Drebrin on the proliferation of PEDV in Vero cells, the eukaryotic expression vector pcDNA3.1-Drebrin-Flag was constructed. After transfection of Vero cells with different concentrations of pcDNA3.1-Drebrin-Flag, cells were infected with PEDV. Our results showed that overexpression of Drebrin in Vero cells could significantly inhibit the intracellular PEDV mRNA level and N protein expression, reduce the extracellular virus titer and inhibit the proliferation of PEDV. Further study on the interaction between Drebrin and PEDV S proteins by laser confocal technique was also performed. The results showed that Drebrin and S protein were co-located in the cytoplasm, suggesting that the two proteins may interact with each other. This study demonstrated for the first time that Drebrin can inhibit PEDV proliferation in Vero cells, laying a foundation for further research in to Drebrin function and provides a valuable information for anti-PEDV research.

2.
Letters in Drug Design & Discovery ; 20(8):1055-1065, 2023.
Article in English | ProQuest Central | ID: covidwho-2325140

ABSTRACT

Introduction: Although, several vaccines are being approved, no effective antiviral drug has been developed for COVID-19 infectious. The present investigation was aimed to increase the essential oils of Cuscuta campestris using far-red light treatment and examine the potential of crude extracts of C. campestris against selected pneumonia pathogens and COVID-19.Methods: Anti-COVID-19 activity was determined in human lung cell lines and COVID-19 positive patients.Results: Results demonstrated that the aqueous extract had the highest amount of anti-COVID-19, antibiotic and antioxidant activity. The far-red light treatment increased Scoparone, cineole, Benzofuran, 2, 3- dihydro, Cinnamic acid, and Benzo[h]quinoline, 2, 4-dimethyl, which are mainly effective components against COVID-19 inflammation and pneumonia microbes. CT scan and clinical laboratory tests in a clinical case study, a 30-year-old woman who presented with severe 2019-nCoV, demonstrated that inhalation of 30 mg extract nebulized/day for seven days resulted in significant improvement in consolidation and ground-glass opacity in lungs on the seventh day of treatment.Conclusion: It is hoped that this study leads to the introduction of some compounds that could be used to formulate new and more potent anti-COVID-19 antibiotics, or other drugs of natural origin in medicine.

3.
Avicenna Journal of Phytomedicine ; 13(3):265-279, 2023.
Article in English | CAB Abstracts | ID: covidwho-2319807

ABSTRACT

Objective: Severe disease onset of COVID-19 may result in alveolar injury and respiratory failure. Apoptosis and inflammation are the main causes of respiratory distress syndrome. Berberine is used in medicine as an analgesic, anti-asthmatic, anti-inflammatory, and antiviral. In the current investigation, the effect of berberine on COVID-19 outpatients was studied. Materials and Methods: The present clinical trial was performed on 40 outpatients who were randomly assigned to berberine (300 mg, TID, 2 weeks) (n=19) or placebo groups (n=21). Both groups received standard therapy and they were monitored on days 3, 7, and 14 after the beginning of the therapy for clinical symptoms' improvement, quantitative CRP, lymphopenia, CBC, and SpO2. The severity and frequency of these symptoms and the level of the parameters were statistically compared between the two groups. Results: On days 0, 3, 7, and 14, there was no significant difference between the berberine and placebo groups in the improvement of clinical symptoms (cough, shortness of breath, nausea, loss of smell and taste, diarrhea, dizziness, sore throat, stomachache, body aches, and body temperature), quantitative CRP, lymphopenia, WBC, neutrophils, platelets, or SpO2. Conclusion: Berberine (300 mg, TID, two weeks) is ineffective in treating COVID-19. More research with a larger sample size is needed to investigate different berberine dosages in other pharmaceutical formulations.

4.
Transboundary and Emerging Diseases ; 2023, 2023.
Article in German | ProQuest Central | ID: covidwho-2305942

ABSTRACT

Feline infectious peritonitis (FIP), which is caused by feline infectious peritonitis virus (FIPV), is a fatal and immunologically mediated infectious disease among cats. At present, due to the atypical clinical symptoms and clinicopathological changes, the clinical diagnosis of FIP is still difficult. The gold standard method for the differential diagnosis of FIP is immunohistochemistry (IHC) which is time-consuming and requires specialized personnel and equipment. Therefore, a rapid and accurate clinical diagnostic method for FIPV infection is still urgently needed. In this study, based on the etiological investigation of FIPV in parts of southern China, we attempted to explore a new rapid and highly sensitive method for clinical diagnosis. The results of the etiological investigation showed that the N gene of the FIPV BS8 strain had the highest homology with other strains. Based on this, a specific FIPV BS8 N protein monoclonal antibody was successfully prepared by expression of the recombinant proteins, immunization of mice, fusion and selection of hybridoma cell lines, and screening and purification of monoclonal antibodies. Furthermore, we carried out a time-saving combination method including indirect immunofluorescence assay (IFA) and nested reverse transcription polymerase chain reaction (RT-nPCR) to examine FIP-suspected clinical samples. These results were 100% consistent with IHC. The results revealed that the combined method could be a rapid and accurate application in the diagnosis of suspected FIPV infection within 24 hours. In conclusion, the combination of IFA and RT-nPCR was shown to be a fast and reliable method for clinical FIPV diagnosis. This study will provide insight into the exploitation of FIPV N antibodies for the clinical diagnosis of FIP-suspected ascites samples.

5.
Applied Organometallic Chemistry ; 2023.
Article in English | Scopus | ID: covidwho-2300741

ABSTRACT

Four copper (II) complexes bearing tris-(2-pyridyl)-pyrazolyl borate (Tppy) ligand with corresponding chloride (Cu-1), aqua (Cu-2), azide (Cu-3), and thiocyanide (Cu-4) substitutions were synthesized and characterized by spectroscopic and analytical methods. Spectroscopic and molecular docking studies were employed to investigate the interactions of these complexes with calf thymus (CT) DNA and bovine serum albumin (BSA). The results inferred intercalation binding mode of the complexes with DNA. All the complexes exhibited good binding with BSA as well. In addition, the binding efficacy of the Cu (II) complexes with SARS-Cov-2 was tested in silico. Further, in vitro anticancer activity of the complexes was investigated against the HeLa-cervical, HepG2-liver and A549-lung cancer, and one normal (L929-fibroblast) cell line. IC50 values unveiled that the complexes were more active than cisplatin against all three cancer cells. It was understood that complex Cu-3 containing azide substitution displayed the highest activity on the HeLa cell line (IC50 = 6.3 μM). More importantly, TppyCu (II) complexes were not active against the normal cell line. Lastly, the acridine orange/ethidium bromide (AO/EB) and 4′,6-diamidino-2-phenylindole staining assays indicated that Cu-3 induced cell death in HeLa cells at the late apoptotic stage. This complex also efficiently generated ROS in HeLa cells promoting apoptosis as understood from the DCFH-DA assay. © 2023 John Wiley & Sons, Ltd.

6.
Curr Neuropharmacol ; 2022 Jul 06.
Article in English | MEDLINE | ID: covidwho-2301002

ABSTRACT

The vascular system plays a critical role in human physiology and diseases. It is a complex subject to study using in vitro models due to its dynamic and three-dimensional microenvironment. Microfluidic technology has recently become a popular technology in various biological fields for its advantages in mimicking complex microenvironments to an extent not achievable by more conventional platforms. Microfluidic technologies can reproduce different vascular system-related structures and functions that can be utilized for drug development and human diseases studies. Herein we first review the relevant structural and functional vascular biology systems of various organ systems and then the fabrication methods to reproduce these vascular districts. We provide a thorough review of the latest achievement in vascular organ-on-chip modeling specific to lung, heart, and the brain microvasculature for drug screening and the study of human disorders.

7.
Inorganics ; 11(2):60, 2023.
Article in English | ProQuest Central | ID: covidwho-2262259

ABSTRACT

Two tetranuclear [Zn4Cl2(ClQ)6]·2DMF (1) and [Zn4Cl2(ClQ)6(H2O)2]·4DMF (2), as well as three dinuclear [Zn2(ClQ)3(HClQ)3]I3 (3), [Zn2(dClQ)2(H2O)6(SO4)] (4) and [Zn2(dBrQ)2(H2O)6(SO4)] (5), complexes (HClQ = 5-chloro-8-hydroxyquinoline, HdClQ = 5,7-dichloro-8-hydroxyquinoline and HdBrQ = 5,7-dibromo-8-hydroxyquinoline) were prepared as possible anticancer or antimicrobial agents and characterized by IR spectroscopy, elemental analysis and single crystal X-ray structure analysis. The stability of the complexes in solution was verified by NMR spectroscopy. Antiproliferative activity and selectivity of the prepared complexes were studied using in vitro MTT assay against the HeLa, A549, MCF-7, MDA-MB-231, HCT116 and Caco-2 cancer cell lines and on the Cos-7 non-cancerous cell line. The most sensitive to the tested complexes was Caco-2 cell line. Among the tested complexes, complex 3 showed the highest cytotoxicity against all cell lines. Unfortunately, all complexes showed only poor selectivity to normal cells, except for complex 5, which showed a certain level of selectivity. Antibacterial potential was observed for complex 5 only. Moreover, the DNA/BSA binding potential of complexes 1–3 was investigated by UV-vis and fluorescence spectroscopic methods.

8.
Food and Agricultural Immunology ; 33(1):65-79, 2022.
Article in English | CAB Abstracts | ID: covidwho-2260461

ABSTRACT

Under the COVID-19 pandemic, interest in immune enhancement and anti-obesity is increasing. Thus, in this study, we investigated whether Kadsura japonica fruits (KJF) exhibits immunostimulatory activity and anti-obesity activity. KJF increased the production of immunostimulatory factors and phagocytosis in RAW264.7 cells. Inhibition of TLR2 and TLR4 blocked KJF-mediated production of immunostimulatory factors in RAW264.7 cells. In addition, the inhibition of MAPK and PI3 K/AKT signaling pathway reduced KJF-mediated production of immunostimulatory factors, and the activation of MAPK and PI3 K/AKT signaling pathway by KJF suppressed the inhibition of TLR2/4. KJF attenuated the lipid accumulation and the protein expression such as CEBPa, PPARP, perilipin-1, adiponectin, and FABP4 related to the lipid accumulation in 3T3-L1 cells. In addition, KJF inhibited excessive proliferation of 3T3-L1 cells and protein expressions such as beta-catenin and cyclin D1 related to cell growth. These findings indicate that KJF may have immunostimulatory activity and anti-obesity activity.

9.
Journal of Southern Agriculture ; 53(4):891-898, 2022.
Article in Chinese | CAB Abstracts | ID: covidwho-2263464

ABSTRACT

Objective: To elucidate the mechanism of interferon gene stimulating factor (STING) in the anti-pathogenic microbial infection of pigs, so as to further provide a reference for the scientific prevention and control of viral diseases such as porcine transmissible gastroenteritis, epidemic diarrhea and porcine pseudorabies. Method: High-scored targets were found in exons 4 and 8 of STING gene and corresponding sgRNA sequences were designed based on CRISPR/ Cas9 technology. The annealed sgRNAs were linked with the enzyme digested LentiCRISPRV2 carrier with T4 DNA ligase to obtain LentiCRISPRV2-STING-sgRNA lentivirus carrier(STING-sgRNA);Different combinations of STING sgRNA lentivirus carriers, packaging plasmid psPAX2 and envelope plasmid pMD2.G were transfected into 293T cells to obtain lentivirus containing sgRNA and then transduced into 3D4/21 cells. Monoclonal cell lines were obtained by puromycin screening and limited dilution method. The knockout efficiencies of the STING gene were identified by PCR amplification, Sequencing and Western blotting;The effect of STING gene knockout on the expression of type I interferon was verified by real-time fluorescent quantitative PCR. Result: When 293T cells were transfected with different combinations of STING-sgRNA lentivirus carrier and HA-STING over expression vector, the editing effect of STING eukaryotic expression carrier could be detected in cells, and the combination of STING-sgRNA(1+5)lentivirus carrier showed the supreme editing efficiency. Thus, the STING-sgRNA(1+5)lentivirus carrier combined with the packaging plasmid psPAX2 and the envelope plasmid pMD2.G were transfected 293T cells to package lentivirus, and then infected 3D4/21 cells with lentivirus. The results showed that a 3D4/21 cell line with a large deletion of the STING gene(4989 bp)was obtained. The STING protein was not observed by Western blotting, indicating that the STING gene knockout 3D4/21 cells(3D4/ 21-STING-/-)were successfully constructed. The transcription level of IFN-beta in 3D4/21-STING-/- cells decreased significantly (P<0.05) compared with parental cells when stimulated by transfection of Haemophilusparasuis DNA. Conclusion : By applying CRISPR/Cas9 technology, STING gene is successfully knock out in 3D4/21 cells, resulting in loss of function of STING gene;STING knockout leads to the transcription disorder of type I interferon when cells are stimulated by DNA, which also suggests that STING gene may be a key factor in the anti-pathogenic microbial infection of pigs.

10.
Eur J Pharm Biopharm ; 184: 62-82, 2023 Mar.
Article in English | MEDLINE | ID: covidwho-2235648

ABSTRACT

The intranasal route has been receiving greater attention from the scientific community not only for systemic drug delivery but also for the treatment of pulmonary and neurological diseases. Along with it, drug transport and permeability studies across the nasal mucosa have exponentially increased. Nevertheless, the translation of data from in vitro cell lines to in vivo studies is not always reliable, due to the difficulty in generating an in vitro model that resembles respiratory human physiology. Among all currently available methodologies, the air-liquid interface (ALI) method is advantageous to promote cell differentiation and optimize the morphological and histological characteristics of airway epithelium cells. Cells grown under ALI conditions, in alternative to submerged conditions, appear to provide relevant input for inhalation and pulmonary toxicology and complement in vivo experiments. Different methodologies and a variety of materials have been used to induce ALI conditions in primary cells and numerous cell lines. Until this day, with only exploratory results, no consensus has been reached regarding the validation of the ALI method, hampering data comparison. The present review describes the most adequate cell models of airway epithelium and how these models are differently affected by ALI conditions. It includes the evaluation of cellular features before and after ALI, and the application of the method in primary cell cultures, commercial 3D primary cells, cell lines and stem-cell derived models. A variety of these models have been recently applied for pharmacological studies against severe acute respiratory syndrome-coronavirus(-2) SARS-CoV(-2), namely primary cultures with alveolar type II epithelium cells and organotypic 3D models. The herein compiled data suggest that ALI conditions must be optimized bearing in mind the type of cells (nasal, bronchial, alveolar), their origin and the objective of the study.


Subject(s)
Cell Culture Techniques , Respiratory Mucosa , Humans , Respiratory Mucosa/metabolism , Cell Line , Lung , Nasal Mucosa , Epithelial Cells/metabolism
11.
Asian Pac J Cancer Prev ; 23(9): 3113-3123, 2022 Sep 01.
Article in English | MEDLINE | ID: covidwho-2205791

ABSTRACT

BACKGROUND: This study was carried out to synthesize a new complex of Fe(II) with isoleucine dithiocarbamate ligand and to determine its potential as an anticancer and antiviral agent for SARSCOV-2. METHODS: The synthesized complexes were then characterized by UV-vis and FT-IR spectroscopy and their melting points. The value of the conductivity of the complex compound is also determined. Anti-cancer activity was tested in vitro and molecular docking. Its potential as an antiviral against SARSCOV-2 was also carried out by molecular docking. Pharmacokinetics/ADMET properties were also carried out on the complex. RESULT: Spectral results showed the successful synthesis of Fe(II) isoleucine dithiocarbamate complex. The complex produced UV-vis spectra at 268 and 575 nm, and the IR data at 399-599 cm-1 showed the coordination between the Fe(II) atoms with sulphur, nitrogen and oxygen of the isoleucine dithiocarbamate ligand. Fe(II) isoleucine dithiocarbamate had a cytotoxicity effect on the MCF-7 cell line (IC50 =613 µg/mL). The complex significantly caused morphological changes in the breast cancer cell line, finally leading to cell apoptosis. CONCLUSION: Cytotoxic test of Fe(II) isoleucine dithiocarbamate showed moderate anticancer activity on MCF-7 cancer cells and showed antiviral activity against SARSCOV-2 by interfering with spike glycoprotein -ACE2 receptors, and inhibiting major proteases and 3Clpro.


Subject(s)
Antineoplastic Agents , COVID-19 Drug Treatment , Coordination Complexes , Angiotensin-Converting Enzyme 2 , Antineoplastic Agents/chemistry , Antiviral Agents/pharmacology , Coordination Complexes/pharmacology , Ferrous Compounds , Humans , Isoleucine , Ligands , Molecular Docking Simulation , Nitrogen , Oxygen , Spectroscopy, Fourier Transform Infrared , Sulfur
12.
Pediatrics ; 150, 2022.
Article in English | ProQuest Central | ID: covidwho-2162657

ABSTRACT

PURPOSE OF THE STUDY: To investigate the role of the mucosal immune system of the upper respiratory tract in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by exploration of the presence of pre-existing mucosal SARS-CoV-2-reactive B cells in tonsillar tissue specimens. STUDY POPULATION: Tonsillar tissue from pediatric patients who underwent tonsillectomy at The Hospital for Sick Children in Toronto, Canada in 2015 to 2016, before the COVID-19 pandemic. METHODS: Using flow cytometry and fluorescently labeled tetramers to the SARS-CoV-2 Spike protein (S-protein), SARS-CoV-2-reactive B cells were isolated from tonsillar tissue. Monoclonal antibodies (mAbs) recognizing the SARS-CoV-2 S-protein were generated from these B-cells using single-cell real time-polymerase chain reaction and RNA sequencing. Human embryonic kidney derived cell lines expressing SARS-CoV-2 S protein were used for in vitro assays assessing the mAbs' SARS-CoV-2 recognition and Ag binding. RESULTS: Pre-existing SARS-CoV-2-reactive B cells were identified and isolated from prepandemic human tonsillar tissue. The mAbs generated from these B cells recognized the S-protein of the wild-type SARS-CoV-2 virus. Additionally, the mAbs originated from naïve B cells as well as Ag-experienced memory B cells, germinal center B cells, and plasma cells. These mAbs were able to partially block binding in vitro by consistently showing >20% inhibition of S-protein binding. The antibodies did not react to the S-proteins of endemic coronaviruses, human coronavirus-OC43 and human coronavirus-229E. The antibodies also demonstrated significantly reduced recognition of the SARS-CoV-2 B.1.1.7 and B1.315 variants. CONCLUSIONS: B cells contained in the lymphoid tissues of the upper respiratory tract can contain pre-existing SARS-CoV-2 reactive antibodies. Monoclonal antibodies generated by these B-cells demonstrated in vitro SARS-CoV-2 recognition and neutralizing potential. However, these mAbs had reduced binding to the Spike proteins of SARS-CoV-2 variants and did not recognize endemic coronaviruses. The existence of these antibodies may explain the variation in COVID-19 symptom severity since these pre-existing Abs may lead to rapid engagement of the SARS-CoV-2 pathogen as the mucosal surface of the respiratory tract is a main point of contact.

13.
China Tropical Medicine ; 22(11):1056-1060, 2022.
Article in Chinese | CAB Abstracts | ID: covidwho-2164285

ABSTRACT

Objective: To explore the antiviral effect of baricitinib in the SARS-CoV-2 infection and influence on cytokine levels.

14.
Front Immunol ; 13: 918817, 2022.
Article in English | MEDLINE | ID: covidwho-2141935

ABSTRACT

Most transcriptomic studies of SARS-CoV-2 infection have focused on differentially expressed genes, which do not necessarily reveal the genes mediating the transcriptomic changes. In contrast, exploiting curated biological network, our PathExt tool identifies central genes from the differentially active paths mediating global transcriptomic response. Here we apply PathExt to multiple cell line infection models of SARS-CoV-2 and other viruses, as well as to COVID-19 patient-derived PBMCs. The central genes mediating SARS-CoV-2 response in cell lines were uniquely enriched for ATP metabolic process, G1/S transition, leukocyte activation and migration. In contrast, PBMC response reveals dysregulated cell-cycle processes. In PBMC, the most frequently central genes are associated with COVID-19 severity. Importantly, relative to differential genes, PathExt-identified genes show greater concordance with several benchmark anti-COVID-19 target gene sets. We propose six novel anti-SARS-CoV-2 targets ADCY2, ADSL, OCRL, TIAM1, PBK, and BUB1, and potential drugs targeting these genes, such as Bemcentinib, Phthalocyanine, and Conivaptan.


Subject(s)
COVID-19 Drug Treatment , COVID-19 , SARS-CoV-2 , COVID-19/genetics , Cell Line , Humans , Leukocytes, Mononuclear , Transcriptome
15.
Acta Agriculturae Universitatis Jiangxiensis ; 43(3):660-664, 2021.
Article in Chinese | CAB Abstracts | ID: covidwho-2113771

ABSTRACT

[Objective] At present, a novel emerging Coronavirus Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has caused an epidemic in the world, seriously threatening human life and health. To establish a basis for a rapid detection method for SARS-CoV-2, the monoclonal antibodies targeting nucleocapsid (N)gene were prepared and identified in this study. [Methods] BA LB/c mice were immunized with purified SARS-CoV-2 N recombinant protein. After four times of immunization. the spleen cells of the mice were fused with SP2/0 myeloma cells. The positive hybridoma cell lines stably secreting monoclonal anti-body were screened through ELISA, and the reactivity of the monoclonal antibody was further determined by western blot and indirect immunofluorescence assay. [Results] After three subclones, two hybridoma cell lines designated as 2D11 and 8G6 were obtained. and the prepared antibodies showed good reactivity with the eukaryotic expression of SARS-CoV-2 N protein. [Conclusion] The monoclonal antibody manufactured in this study can be used for SARS-CoV-2 detection.

16.
Front Cell Infect Microbiol ; 12: 1003608, 2022.
Article in English | MEDLINE | ID: covidwho-2109735

ABSTRACT

As new pathogens emerge, new challenges must be faced. This is no different in infectious disease research, where identifying the best tools available in laboratories to conduct an investigation can, at least initially, be particularly complicated. However, in the context of an emerging virus, such as SARS-CoV-2, which was recently detected in China and has become a global threat to healthcare systems, developing models of infection and pathogenesis is urgently required. Cell-based approaches are crucial to understanding coronavirus infection biology, growth kinetics, and tropism. Usually, laboratory cell lines are the first line in experimental models to study viral pathogenicity and perform assays aimed at screening antiviral compounds which are efficient at blocking the replication of emerging viruses, saving time and resources, reducing the use of experimental animals. However, determining the ideal cell type can be challenging, especially when several researchers have to adapt their studies to specific requirements. This review strives to guide scientists who are venturing into studying SARS-CoV-2 and help them choose the right cellular models. It revisits basic concepts of virology and presents the currently available in vitro models, their advantages and disadvantages, and the known consequences of each choice.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Cell Line , China
17.
Journal of Tropical Medicine ; 21(9):1119-1124, 2021.
Article in Chinese | CAB Abstracts | ID: covidwho-2047145

ABSTRACT

Objective: To investigate the effects of miR-221-3p on the proliferation and apoptosis of vascular smooth muscle cells (VSMC) in abdominal aortic aneurysm (AAA) by targeting tissue inhibitor of metalloproteinase- 2 (TIMP-2).

18.
Zhongguo Bingyuan Shengwuxue Zazhi / Journal of Pathogen Biology ; 15(9):997-1004, 2020.
Article in Chinese | CAB Abstracts | ID: covidwho-2040442

ABSTRACT

Objective: To investigate the molecular mechanism of the action by which the MERS-CoV E proxein induces autophagy in 293T cells.

19.
Journal of South China Agricultural University ; 41(5):27-35, 2020.
Article in Chinese | CAB Abstracts | ID: covidwho-2040361

ABSTRACT

Objective: To prepare monoclonal antibodies against porcine epidemic diarrhea virus (PEDV) N protein, and develop an indirect immuno-fluorescence assay method used for detecting PEDV. Method: The expressed recombinantly PEDV N protein was used as an immunogen and 8-week-old female BALB/c mice were immunized. Then their spleen cells with high antibody titer were isolated and fused with SP2/0 cells. The hybridoma cell lines secreting monoclonal antibodies against PEDV N protein were screened. In Vero cells infected with PEDV, monoclonal antibody of anti-PEDV N protein was used as the primary antibody and FITC-goat-anti-mouse IgG was used as the secondary antibody to develop indirect immuno-fluorescence assay method used for detecting PEDV. Result: The prepared hybridoma cell lines could stably secrete anti-PEDV N protein antibodies, ELISA antibody titer in cell supernatant was above 1:3 200, and in mouse ascites above 1:1 000 000. While monoclonal antibodies were applied in established indirect immuno-fluorescence assay, the optimal conditions were that cells were fixed with 80% () acetone at -20 degrees C for 30 min;The primary antibody was diluted 1 000 times by PBS buffer solution and incubated at 4 degrees C overnight;The secondary antibody was diluted 100 times by PBS buffer solution and incubated at 37 degrees C for 1 h. Transmissible gastroenteritis virus (TGEV), classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine reproductive virus (PRV), porcine enteric a corone virus (PEAV), porcine rotavirus (PoRV) and PEDV were detected by established indirect immuno-fluorescence assay method, only PEDV showed positive, all the else viruses showed negative.

20.
Acta Veterinaria et Zootechnica Sinica ; 53(6):2024-2028, 2022.
Article in Chinese | CAB Abstracts | ID: covidwho-2025545

ABSTRACT

This study aimed to analyze the proliferation characteristics of porcine deltacoronavirus (PDCoV) in suspension cultured porcine kidney cells LLC-PK1, so as to provide Candidate cell for large-scale production of PDCoV inactivated vaccine. LLC-PK1 cells were suspended by gradually decreasing serum method. PDCoV adaptive monoclonal cell lines were screened by limited dilution method. Indirect immunofluorescence method was used to identify the infectivity of PDCoV. The initial cell density, MOI, time of receiving virus collection and TPCK pancreatin concentration were screened to determine the best suspension culture conditions. The suspension cell strain LLC-PK1Sa which can proliferate PDCoV efficiently was screened out;PDCoV can specifically infect LLC-PK1 cells;PDCoV inoculated LLC-PK1Sa cells with a density of 2 x 106 cells.mL-1 according to the MOI of 10-3, When the final concentration of TPCK pancreatin reached 7.5 g.mL-1, the titer of virus solution harvested 48 h after inoculation was the highest. In this study, the efficient proliferation of PDCoV in LLC-PK1Sa suspension cells was realized for the first time, and the suspension culture conditions were preliminarily optimized, which could provide theoretical reference for large-scale production of PDCoV inactivated vaccine.

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