Pathogenicity of 2 porcine deltacoronavirus strains in gnotobiotic pigs.
Ontology highlight
ABSTRACT:
SUBMITTER: Jung K
PROVIDER: S-EPMC4378491 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Porcine deltacoronavirus (PDCoV) is a novel enteropathogenic coronavirus in pigs. We have isolated and passaged the PDCoV strain OH-FD22 in an LLC porcine kidney (LLC-PK) cell line. Our study investigated the pathogenicity of the tissue-culture-grown PDCoV (TC-PDCoV) OH-FD22 at cell passages 5, 20 and 40 in LLC-PK cells, in eight 14-day-old gnotobiotic (Gn) pigs. Pigs (n = 3) were euthanized for pathologic examination at post-inoculation day (PID) 3, and the remainder were monitored for clinical signs, virus shedding, and serum antibody responses until PID 28. All inoculated pigs developed watery diarrhea and/or vomiting at PID 1-2 and shed the highest amount of viral RNA in feces at PID 3-5, accompanied by severe atrophic enteritis. They developed high titers of PDCoV-specific IgG/IgA and virus-neutralizing antibodies in serum at PID 23-24. Histologic lesions were limited to the villous epithelium of the jejunum and ileum at PID 3. Two inoculated pigs tested at PID 23-24 had small to moderate numbers of PDCoV antigen-positive cells in the intestinal lamina propria and mesenteric lymph nodes, but not in enterocytes. An analysis of full-length S and N genes of TC- and Gn-pig-passaged OH-FD22 revealed a high genetic stability in cell culture and pigs. TC-PDCoV OH-FD22 (cell passages 5, 20 and 40) was enteropathogenic, and the pathogenicity was similar to that of the original field virus. The TC-PDCoV OH-FD22 will be useful for further pathogenesis studies and for evaluating if higher-level cell-culture passaged virus becomes attenuated for vaccine development.
| S-EPMC7087098 | biostudies-literature
Project description:Porcine deltacoronavirus (PDCoV) have recently emerged in several swine producing countries. Our survey found that in addition to porcine epidemic diarrhoea virus (PEDV), PDCoV has also been a causative enteric pathogen of diarrhoeic outbreaks occurring at swine farms around Japan since late 2013. Phylogenetic analysis using the complete genomes of PDCoVs detected in Japan in 2014 demonstrated that the PDCoVs from Japan may be closely related to the PDCoVs from the U.S. and Korea during 2013 to 2014 but not the PDCoVs from China and Hong Kong during 2004 to 2016 and from Thailand, Vietnam and Laos during 2015 to 2016. To investigate the pathogenicity of a representative Japanese PDCoV, we performed an experimental infection using hysterectomy-produced colostrum-deprived piglets. The PDCoV-inoculated piglets showed acute, watery diarrhoea, but all recovered and survived. In addition, all piglets inoculated with the Japanese PDCoV exhibited virus shedding at high level in faeces and viremia corresponding to their clinical symptoms. In the PDCoV-inoculated group, viruses were mainly detected from jejunums to colons by a quantitative PDCoV-specific PCR and microscopic observation. These findings would provide useful information for establishing a diagnostic methodology for distinguishing diarrhoea caused by PDCoV from that caused by other enteric pathogens, such as PEDV.
| S-EPMC7172274 | biostudies-literature
Project description:Porcine deltacoronavirus strain CHN-SC2015，complete genome
| PRJNA510271 | ENA
Project description:Porcine deltacoronavirus Genome sequencing and assembly
| PRJNA851852 | ENA
Project description:Porcine deltacoronavirus (PDCoV) is a newly emerging enteric pathogen in swine that causes diarrhea in neonatal piglets and creates an additional economic burden on porcine industries in Asia and North America. In this study, a PDCoV isolate, CHN-SC2015, was isolated from Sichuan Province in southwest China. The isolate was characterized by a cytopathic effect, immunofluorescence, and electron microscopy. CHN-SC2015 titers in LLC-PK cells ranged from 104.31 to 108.22 TCID50/mL during the first 30 passages. During serial passage, 11 nucleotide mutations occurred in the S gene, resulting in nine amino acid changes. A whole genome sequencing analysis demonstrated that CHN-SC2015 shares 97.5%-99.1% identity with 59 reference strains in GenBank. Furthermore, CHN-SC2015 contained 6-nt deletion and 9-nt insertion in the ORF1ab gene, 3-nt deletion in the S gene and 11-nt deletion in its 3'UTR compared with other reference strains available in GenBank. A phylogenetic analysis showed that CHN-SC2015 is more closely related to other PDCoV strains in China than to the strains from Southeast Asia, USA, Japan, and South Korea, indicating the diversity of genetic relationships and regional and epidemic characteristics among these strains. A recombination analysis indicated that CHN-SC2015 experienced recombination events between SHJS/SL/2016 and TT-1115. In vivo infection demonstrated that CHN-SC2015 is highly pathogenic to sucking piglets, causing diarrhea, vomiting, dehydration, and death. Virus was shed daily in the feces of infected piglets and upon necropsy, was found distributed in the gastrointestinal tract and in multiple organs. CHN-SC2015 is the first systematically characterized strain from southwest China hitherto reported. Our results enrich the body of information on the epidemiology, pathogenicity and molecular evolution associated with PDCoV.
| S-EPMC6893596 | biostudies-literature
Project description:Porcine deltacoronavirus (PDCoV) is a novel swine enteropathogenic coronavirus that causes acute diarrhea, vomiting, dehydration and mortality in neonatal piglets, resulting in significant economic losses to the pig industry. However, there is currently little information on vaccine studies and commercially available vaccines for PDCoV. Hence, herein, a PDCoV strain, CH/XJYN/2016, was successfully isolated and serially propagated in vitro, and its biological characteristics were determined. Compared to that of previously reported and recently isolated PDCoV strains from China and the United States, the S gene of the CH/XJYN/2016 strain contains novel mutations. Infection studies revealed that CH/XJYN/2016 is pathogenic to suckling piglets and conventional weaned pigs. In addition, the median pig diarrhea dose (PDD50) of PDCoV in conventional weaned pigs was determined (2.0 log10PDD50/3?mL). Furthermore, an inactivated cell-adapted CH/XJYN/2016-based vaccine candidate was developed with different adjuvants. Compared with nonvaccinated pigs, conventional weaned pigs given the inactivated vaccine developed a potent humoral immune response and showed no clinical signs or viral shedding after challenge, indicating a potent protective effect of the vaccine against PDCoV infection. Therefore, the PDCoV vaccine developed in this study is a promising vaccine candidate that can be used for the control of PDCoV infection in pigs.
| S-EPMC7125813 | biostudies-literature
Project description:The porcine small intestinal epithelial cell line, IPEC-J2, is useful to characterize the interactions of enterocytes with enteric viruses in vitro. We investigated whether IPEC-J2 cells are susceptible to porcine deltacoronavirus (PDCoV) infection. We conducted quantification of infectious virus or viral RNA, immunofluorescent (IF) staining for the detection of PDCoV antigens, and TUNEL assay in IPEC-J2 cells inoculated with the strain OH-FD22-P8 grown in LLC-PK cells, and supplemented with 10??g/ml of trypsin in the cell culture medium. Cytopathic effects (CPE) that consisted of enlarged and rounded cells followed by cell shrinkage and detachment, were identified by the 3rd viral passage in the IPEC-J2 cells. PDCoV antigen was detected in the cells showing CPE. By double IF and TUNEL staining, most PDCoV antigen-positive IPEC-J2 cells failed to show TUNEL-positive signals, indicating that PDCoV-infected IPEC-J2 cells may not undergo apoptosis, but rather necrosis, similar to necrotic cell death of infected enterocytes in vivo. There was increased interleukin-6 in PDCoV-infected IPEC-J2 cell culture supernatants at post-inoculation hour (PIH) 48-96, as evaluated by ELISA, concurrent with increased titers of PDCoV at PIH 24-72. The susceptibility of IPEC-J2 cells to PDCoV infection supports their usefulness to characterize the interactions of enterocytes with PDCoV. We also demonstrated that IPEC-J2 cell culture-passaged PDCoV (OH-FD22-P8-I-P4) was enteropathogenic in 10-day-old gnotobiotic pigs, and induced systemic innate and pro-inflammatory cytokine responses during the acute PDCoV infection.
| S-EPMC7117386 | biostudies-literature
Project description:To understand the progression of porcine epidemic diarrhea virus infection, we inoculated gnotobiotic pigs with a newly emerged US strain, PC21A, of the virus. At 24–48 hours postinoculation, the pigs exhibited severe diarrhea and vomiting, fecal shedding, viremia, and severe atrophic enteritis. These findings confirm that strain PC21A is highly enteropathogenic.
| S-EPMC3966387 | biostudies-literature
Project description:Porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV) are epizootic swine viruses. To detect and study the evolution of PEDV and PDCoV in central China (Shanxi, Henan, Hubei province), 70 clinical intestinal and fecal samples from piglets with severe watery diarrhea during August 2015 and June 2016 were collected, tested and analyzed. PEDV was more frequently detected by PCR than PDCoV. Phylogenetic analysis of S genes showed that the 10 PEDV strains from this study clustered into G2a (n?=?7) and G2b (n?=?3) groups. Additionally, the three G2b strains (PEDV S2?) contained the same specific 3?nt deletion in S2 as other reference strains in G2b. Interestingly, complete genome analysis indicated that CH/hubei/2016 was closer to the US INDEL strain and G2a group. CH/hubei/2016 had one recombination event in S2 gene which may have resulted from AH2012-12 (from G2b group) and CH-ZMDZY-11 (from G2a group). Furthermore, 10 purifying selection sites in S gene indicated an adaptive evolution of PEDV in central China swine herds. These results suggested that Pandemic G2a and G2b are predominant PEDV genotype circulating in central China. In addition, the deletion and recombination identified in S gene suggested PEDV strains of central exhibited an evolutionary variety. However, whether these changes affect the pathogenicity and antigenicity of wild PEDV is unknown and is worth for further investigation.
| S-EPMC7111851 | biostudies-literature
Project description:Porcine deltacoronavirus (PDCoV) was first detected in Hong Kong and has recently spread to many countries around the world. PDCoV causes acute diarrhea and vomiting in pigs, resulting in significant economic losses in the global pork industry. In this study, a Chinese PDCoV strain, designated CHN-HG-2017, was isolated from feces of a suckling piglet with severe watery diarrhea on a farm located in central China. Subsequently, the virus was identified by an indirect immunofluorescence assay and electron microscopy. A nucleotide sequence alignment showed that the whole genome of CHN-HG-2017 is 97.6%-99.1% identical to other PDCoV strains. Analysis of potential recombination sites showed that CHN-HG-2017 is a possible recombinant originating from the strains CH/SXD1/2015 and Vietnam/HaNoi6/2015. Furthermore, the pathogenicity of this recombinant PDCoV strain was investigated in 5-day-old piglets by oral inoculation. The challenged piglets developed typical symptoms, such as vomiting, anorexia, diarrhea and lethargy, from 1 to 7 days post-inoculation (DPI). Viral shedding was detected in rectal swabs until 14 DPI in the challenged piglets. Interestingly, high titers of virus-neutralizing antibodies in sera were detected at 21 DPI. Tissues of small intestines from CHN-HG-2017-infected piglets at 4 DPI displayed significant macroscopic and microscopic lesions with clear viral antigen expression. Our analysis of the full genome sequence of a recombinant PDCoV and its virulence in suckling piglets might provide new insights into the pathogenesis of PDCoV and facilitate further investigation of this newly emerged pathogen.
| S-EPMC7087286 | biostudies-literature