Ping Jiang

Nanjing Agricultural University, Nan-ching, Jiangsu Sheng, China

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Publications (83)190.47 Total impact

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    ABSTRACT: Porcine reproductive and respiratory syndrome virus (PRRSV) is an important pathogen that is responsible for large economic losses in the swine industry worldwide. In PRRSV strains, many genetic variations occur in the central hypervariable region (HV2) of the Nsp2 gene, which encodes non-structural protein 2. For example, PRRSV strains VR2332, Em2007, MN184C, and TJM-F92 contained variations in the Nsp2 sequences and exhibited differing levels of virulence in adult pigs. However, the role of HV2 with respect to PRRSV immunity is unclear. In this study, four recombinant PRRSV strains (rBB/+30aa, rBB/Δ68aa, rBB/Δ111aa, and rBB/Δ120aa) were rescued using a highly pathogenic type 2 PRRSV cDNA clone (pBB). All rescued strains displayed similar growth characteristics to the parental rBB virus in pulmonary alveolar macrophages (PAMs). Expression levels of inflammatory cytokines IL-β, IL-6, and TNF-α were significantly lower, at the mRNA and protein level, for groups infected with rBB/Δ111aa and rBB/Δ120aa than those in the rBB group. Levels of these inflammatory cytokines in the rBB/+30aa and rBB/Δ68aa groups were not significantly different with those in the rBB group. Phosphorylation levels of IκB were decreased to a greater extent in the rBB/Δ111aa and rBB/Δ120aa groups compared with those in the rBB/+30aa, rBB/Δ68aa, and rBB groups. Our results indicate that amino acids 323-433 and 628-747 of Nsp2 failed to exert significant effects on PRRSV replication in PAMs, but modulated the expression of inflammatory cytokines in vitro. Copyright © 2015. Published by Elsevier B.V.
    Virus Research 06/2015; 208. DOI:10.1016/j.virusres.2015.05.016 · 2.83 Impact Factor
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    ABSTRACT: Secretory component (SC) is a component of secretory IgA that is designated sIgA to distinguish it from IgA. The monoclonal antibody (MAb) against SC has been shown to be an excellent tool for the detection of the level of sIgA and for the evaluation of the efficacy of mucosal immunity. To prepare a monoclonal antibody against porcine SC, a recombinant porcine SC was expressed and purified. To develop this recombinant SC, the gene encoding the porcine SC was ligated into the pCold I vector. The recombinant vector was then transformed into Escherichia coli BL 21 (DE3), and gene expression was successfully induced by isopropyl-β-d-thiogalactoside (IPTG). After affinity purification with Ni-NTA resin and gel recovery, the recombinant SC protein was used to immunize BALB/c mice. Finally, three hybridoma cell lines showing specific recognitions of both recombinant SC and native SC were used as stable secretors of MAbs against porcine SC and were confirmed to have no reaction to porcine IgA or IgG. The successful preparation of recombinant SC protein and MAbs provides valuable materials that can be used in the mucosal infection diagnosis for porcine disease and mucosal immune evaluation for porcine vaccine, respectively. Copyright © 2015. Published by Elsevier Inc.
    Protein Expression and Purification 05/2015; 113. DOI:10.1016/j.pep.2015.04.013 · 1.51 Impact Factor
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    ABSTRACT: Porcine reproductive and respiratory syndrome virus (PRRSV) is mainly responsible for the heavy economic losses in pig industry in the world. A number of neutralizing epitopes have been identified in the viral structural proteins GP3, GP4, GP5 and M. In this study, the important amino acid (aa) residues of HP-PRRSV strain BB affecting neutralization susceptibility of antibody were examined using resistant strains generated under neutralizing antibody (NAb) pressure in MARC-145 cells, reverse genetic technique and virus neutralization assay. HP-PRRSV strain BB was passaged under the pressure of porcine NAb serum in vitro. A resistant strain BB34s with 102 and 104 aa substitutions in GP5, which have been predicted to be the positive sites for pressure selection (Delisle et al., 2012), was cloned and identified. To determine the effect of the two aa residues on neutralization, 8 recombinant PRRSV strains were generated, and neutralization assay results confirmed that the aa residues 102 and 104 in GP5 played an important role in NAbs against HP-PRRSV in MARC-145 cells and porcine alveolar macrophages. Alignment of GP5 sequences revealed that the variant aa residues at 102 and 104 were frequent among type 2 PRRSV strains. It may be helpful for understanding the mechanism regulating the neutralization susceptibility of PRRSV to the NAbs and monitoring the antigen variant strains in the field. Copyright © 2015. Published by Elsevier B.V.
    Virus Research 04/2015; 204. DOI:10.1016/j.virusres.2015.04.015 · 2.83 Impact Factor
  • PLoS ONE 04/2015; 10(4):e0122678. DOI:10.1371/journal.pone.0122678 · 3.53 Impact Factor
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    ABSTRACT: Recently, a series of acute swine erysipelas outbreaks occurred in Eastern China. Eight strains isolated from cases of septicemia were determined as serotype 1a, and 4 of the isolates were resistant to acriflavine. One isolate strain named HX130709 was attenuated on agar media containing acriflavine dye. The 432-bp hypervariable region in spaA gene of the field and attenuated strains were amplified and sequenced. It was further compared with the vaccine strain G4T10, and thus, the eight field strains can be divided into four spaA-types. The partial spaA gene analysis also showed that no point mutations occurred among different archived passages of HX130709 during the attenuation. Results of pulsed-field gel electrophoresis showed that eight distinct patterns with 22 to 30 DNA fragment bands were produced from field strains, and twelve distinct patterns with 23 to 27 DNA fragment bands were produced from different passages of the attenuated strains. Mouse pathogenicity test showed that the mortality of the mice infected with 104 CFU field strains was 100% and the attenuation of strain HX130709 occurred between 46 and 50 passages. All the field and attenuated strains were highly sensitive to β-lactam antibiotics, tetracyclines and macrolides. So, we can make conclusions that the acute swine erysipelas outbreaks in Eastern China were caused by serotype 1a E. rhusiopathiae strains with different biochemical characteristics, and the virulence of serotype 1a E. rhusiopathiae strains is unrelated with some point mutations in 432-bp hypervariable region of the spaA gene.
    Journal of Veterinary Medical Science 02/2015; DOI:10.1292/jvms.14-0589 · 0.88 Impact Factor
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    ABSTRACT: Porcine reproductive and respiratory syndrome virus (PRRSV) usually establishes a prolonged infection and causes an immunosuppressive state. It has been proposed that interleukin-10 (IL-10) plays an important role in PRRSV-induced immunosuppression. However, this mechanism has not been completely elucidated. In this study, we found that transfection of 3D4/2 macrophages with the N protein gene of type 2 PRRSV significantly upregulated IL-10 expression at the transcriptional level. Moreover, alanine substitution mutation analysis revealed that the N protein residues 33-37, 65-68, and 112-123 were related to the upregulation of IL-10 promoter activity. Recombinant PRRSV with mutations at residues 33-37 in the N protein (rQ33-5A and rS36A), recovered from corresponding infectious cDNA clones, induced significantly lower levels of IL-10 production in infected monocyte-derived dendritic cells, as compared to their revertants rQ33-5A(R) and rS36A(R), and the wild-type recombinant PRRSV strain rNT/wt. These data indicate that type 2 PRRSV N protein plays an important role in IL-10 induction and the N-N non-covalent domain is associated with this activity.
    Journal of General Virology 01/2015; 96(Pt_6). DOI:10.1099/vir.0.000061 · 3.53 Impact Factor
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    ABSTRACT: Porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) are very two important pathogens that have coursed huge economic losses in swine production in worldwide. In this study,a vector pCMV-TJM containing the full-length cDNA clone of PRRSV attenuated strain TJM-F92 was firstly constructed by PCR method. Then a gene sequence containing Afl II/Mlu I e restriction enzyme sites and a transcription regulatory sequence for ORF6 (TRS6) was inserted be- tween ORF7 and 3'UTR, yielding a expression vector pCMV-TJM-TRS. Subsequently, a plasmid pCMV-TJM-Cap was constructed by cloning of PCV2 ORF2 gene into the unique sites Afl II /Mlu I of pCMV- TJM-TRS plasmid DNA. Then three recombinant PRRSV, rTJM, rTJM/TRS and rTJM/Cap, were rescued by transfection of pCMV-TJM, pCMV-TJM-TRS and pCMV-TJM-Cap into Marc-145 cells, respectively,and confirmed by the genome sequence, restriction enzyme digestion, Western Blot and IFA. They all had the molecular markers which was different from the parent virus. The growth characteristics of the rescued viruses were similar to that of parent virus. rTJM/Cap could also express efficiently PCV2 Cap protein in Marc-145 cells. At passage 8, it still had PCV2 ORF2 gene which examined by RT-PCR. It indicated that the full-length cDNA clone of PRRSV attenuated strain TJM-F92 and recombinant PRRSV rTJM/Cap expressing PCV2 Cap protein were successfully constructed. It made an important foundation for studying on the pathogenic mechanisms of PRRSV and PRRSV-PCV2 vaccine in the future.
    Bing du xue bao = Chinese journal of virology / [bian ji, Bing du xue bao bian ji wei yuan hui] 01/2015; 31(1):65-73.
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    ABSTRACT: Porcine diarrhea outbreaks caused by porcine epidemic diarrhea virus (PEDV) has occurred in China with significant losses of piglets since 2010. In this study, the complete S and ORF3 genes of 15 field PEDV isolates in mid-eastern China from 2011 to 2013 were detected and compared with other reference strains. Based on S gene, all of the PEDV strains could be assigned to 3 genogroups. Only 1 isolate, JS120103, belonged to genogroup 1 and showed a close relationship with previous Chinese strains DX and JS-2004-2, European strain CV777, and Korean strain DR13. The other 14 isolates belonged to genogroup 3 and showed a close relationship with other Chinese strains isolated after 2010. The S genes of those isolates were 9 nucleotides longer in length than JS120103 and the other reference strains in genogroup 1, with 15 bp insertion and 6 bp deletion. Homology analyses revealed that all of the Chinese field isolates, except JS120103, are 97.6% to 100% (95.8% to 100%) identical in nucleotide (deduced amino acid) sequence to each other. Meanwhile, based on the ORF3 gene, all of the PEDV isolates could be separated into 3 genogroups. Eleven of the 15 field isolates in this study belonged to genogroup 3 and were 95.8% to 100% identical in nucleotide sequence or 95.6% to 100% in deduced amino acid sequence to each other. Our results indicate that the variant PEDV strain spread wildly in mid-eastern China. This will be useful to take into consideration in the control and prevention of this disease.
    Canadian journal of veterinary research = Revue canadienne de recherche vétérinaire 01/2015; 79(1). · 0.85 Impact Factor
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    ABSTRACT: Background Encephalomyocarditis virus (EMCV) can cause myocarditis, respiratory failure, reproductive failure, and sudden death in pre-weaned piglets, which has been isolated in China. EMCV VP1 protein was one of the most important structural proteins and played an important role in the protective immunity. In this study, 10 monoclonal antibodies (McAbs) against EMCV VP1 were screened and identified.ResultsEpitope mapping results indicated that McAbs (6E11, 7A7, 7C9) specifically recognized the linear epitopes V(2)ENAEK(7), McAbs (1D1, 2A2, 5A1, 5A11, 5G1) recognized the epitope F(19)VAQPVY(25), and McAbs 1G8 and 3A9 recognized P(42)IGAFTVK(49). Protein sequence alignment of VP1 with 16 EMCV isolates indicated that the epitope F(19)VAQPVY(25) was conserved in all the reference strains. The epitopes P(42)IGAFTVK(49) and V(2)ENAEK(7) only had 1 or 2 variable amino acid among the reference strains. The 3D model analysis results showed that these epitopes presented as spheres were shown within the context of the complete particle.Conclusions In this study, ten McAbs against EMCV VP1 were developed and three B-cells epitopes (2-7aa, 19-25aa and 42-49aa) were defined in VP1. All the results herein will promote the future investigations into the function of VP1 of EMCV and development of diagnostic methods of EMCV.
    Virology Journal 12/2014; 11(1):2507. DOI:10.1186/s12985-014-0226-8 · 2.09 Impact Factor
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    ABSTRACT: Encephalomyocarditis virus (EMCV) infects animals of various species and causes a variety of clinical symptoms. In this study, an infectious full-length cDNA clone was constructed, and the characteristics of the rescued virus were investigated in vitro and in vivo. Our data demonstrated that the growth kinetics in vitro and plaque morphology of the rescued EMCV rNJ08 strain were similar to those of the parental strain. Although rNJ08 infected BALB/c mice, none of the mice died during the observation period of 14 days post-inoculation. The availability of the infectious cDNA clone provides a genetic platform for studying gene function and for the rational design of vaccines.
    Archives of Virology 11/2014; 160(3). DOI:10.1007/s00705-014-2290-1 · 2.28 Impact Factor
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    ABSTRACT: Adhesion protein MSG1 mediating adherence to porcine erythrocytes in Mycoplasma suis (M. suis) invasion has been identified previously. In order to determine the host membrane proteins that interact with MSG1, recombinant His-tagged MSG1 (rMSG1) was used to screen for interacting proteins in the protein extracts of porcine erythrocyte membrane. Potential rMSG1-interacting proteins were initially identified as band 3 and β-actin with molecular weight of 46 and 45 kDa, respectively. Immune fluorescence results showed that rMSG1 can specifically bind with the β-actin of HeLa, BHK-21, and HEK-293A cells, respectively. RNA interference assays further demonstrated that the interaction between β-actin and rMSG1 on HeLa cells was specific and dose dependent. Confocal microscopy showed that both rMSG1 and M. suis can partially co-localize with β-actin on the surface of porcine erythrocytes. Pull-down assays showed that rMSG1 can directly interact with β-actin. Our study is the first to report the interaction of MSG1 with β-actin, which will be of help to understand the pathogenesis of M. suis and develop a cultivation system.
    Archives of Microbiology 10/2014; 197(2). DOI:10.1007/s00203-014-1050-7 · 1.86 Impact Factor
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    ABSTRACT: A highly virulent and antigenic variant of pseudorabies virus (PRV) broke out in China at the end of 2011 and caused great economic loss in the pig industry. In this study, an infectious bacterial artificial chromosome (BAC) clone containing the full-length genome of the emerged variant PRV ZJ01 strain was generated. The BAC-derived viruses, vZJ01-GFPΔgE/gI (gE/gI deleted strain, and exhibiting green autofluorescence), vZJ01ΔgE/gI (gE/gI deleted strain), and vZJ01gE/gI-R (gE/gI revertant strain), showed similar in vitro growth to their parent strain. In pigs, inactivated vZJ01ΔgE/gI vaccine generated significantly high levels of neutralizing antibodies against ZJ01 compared with Bartha-K61 live vaccine (p<0.05). After fatal ZJ01 challenge, all five animals in the inactivated vZJ01ΔgE/gI vaccine group survived without exhibiting any clinical sings, but two of five animals exhibited central nervous signs in the Bartha-K61 group. Meanwhile, all the non-vaccinated control animals died at 7 days post-challenge. This indicates that the inactivated vZJ01ΔgE/gI vaccine is a promising vaccine candidate for controlling the variant strains of PRV now circulating in China.
    Virus Research 09/2014; 195. DOI:10.1016/j.virusres.2014.09.003 · 2.83 Impact Factor
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    ABSTRACT: Here, we used reverse transcription-PCR (RT-PCR) and western blot to detect protease-activated receptor (PAR) 1, PAR 2 and PAR 4 expression in cancer tissues and cell lines of esophageal squamous cell carcinoma, and investigated the co-relationship between PAR expression and clinic-pathological data for esophageal cancer. The methylation of PAR4 gene promoter involved in esophageal carcinoma was also analyzed. By comparing the mRNA expressions of normal esophageal tissue and human esophageal epithelial cells (HEEpiC), we found that among the 28 cases of esophageal squamous cell carcinoma, PAR1 (60%) and PAR2 (71%) were elevated in 17 and 20 cases, respectively, and PAR4 (68%) expression was lowered in 19 cases. Whereas, in human esophageal squamous cells (TE-1 and TE-10), PAR1 and PAR2 expression was increased but PAR4 was decreased. Combined with clinical data, the expression of PAR1 in poorly differentiated (P=0.016) and middle and lower parts of the esophagus (P=0.016) was higher; expression of PAR4 in poorly differentiated carcinoma was lower (P=0.049). Regarding TE-1 and TE-10 protein expression, we found that in randomized esophageal carcinoma, PAR1 (P=0.027) and PAR2 (P=0.039) expressions were increased, but lowered for PAR4 (P=0.0001). In HEEpiC, TE-1, TE-10, esophageal and normal esophagus tissue samples (case No. 7), the frequency of methylation at the 19 CpG loci of PAR4 was 35.4%, 95.2%, 83.8%, 62.6% and 48.2%, respectively. Our results indicate that the expression of PAR1 and PAR2 in esophageal squamous cell carcinoma is increased but PAR4 is decreased. Hypermethylation of the promoter of the PAR4 gene may contribute to reduced expression of PAR4 in esophageal squamous cell carcinoma.
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    ABSTRACT: Parainfluenza virus type 3 (PIV3) is one of the most important viral respiratory pathogens for humans and for many animals, but goat infection has been rarely reported. Starting in Aug 2013, goats in the Jiangsu and Anhui provinces of eastern China suffered severe respiratory diseases. In order to identify the causative agent, numerous related pathogens were tested with RT-PCR or PCR. A unique PIV3 strain was detected in most of the clinical nasal swabs or serum samples. The virus was isolated on MDBK cells and characterized by RT-PCR, nucleotide sequence analysis and hemagglutination test. The entire M and F gene coding regions, HN, 5′-UTR-N and L gene fragments were amplified using pairs of degenerate primers. Nucleotide, amino acid sequence alignments and phylogenetic analyses based on these genes indicated that the goat-derived PIV3 strain was distinct from previously reported BPIV3 genotypes and HPIV3 strains. The novel isolate, named JS2013, might be a potentially new member of the respirovirus genus. Goats were experimentally infected with JS2013 culture. The virus-inoculated goats displayed coughing and nasal discharges that were related to respiratory diseases. Viremia and virus shedding were detected during 4-10 days post inoculation (dpi). Virus-specific HI antibodies became positive from 14 dpi. This is the first report of the detection of PIV3 from Chinese goat herds and genetic and pathogenetic characterization of the novel goat-derived PIV3.
    Veterinary Microbiology 09/2014; 174(1-2). DOI:10.1016/j.vetmic.2014.08.027 · 2.73 Impact Factor
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    ABSTRACT: Porcine circovirus type 2 (PCV2) has been identified as the essential causal agent of post-weaning multisystemic wasting syndrome, which has spread worldwide. To discover cellular protein responses of PK-15 cells to PCV2 infection, two-dimensional liquid chromatography-tandem mass spectrometry (MS) coupled with isobaric tags for relative and absolute quantification (iTRAQ) labeling was employed to quantitatively identify the proteins that were differentially expressed in PK-15 from the PCV2-infected group compared to the uninfected control group. A total of 196 cellular proteins in PK-15 that were significantly altered at different time periods post-infection were identified. These differentially expressed proteins were related to the biological processes of binding, cell structure, signal transduction, cell adhesion, etc. and their interactions. Moreover, some of these proteins were further confirmed by Western blot. The high number of differentially expressed proteins identified should be very useful in elucidating the mechanism of replication and pathogenesis of PCV2 in the future.
    Virus Genes 08/2014; 49(3). DOI:10.1007/s11262-014-1106-4 · 1.84 Impact Factor
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    ABSTRACT: Wild chrysanthemum (Chrysanthemum indicum L.) is traditionally used in folk medicine as an anti-inflammatory agent. It is also used in the southwest plateau region of China to prevent ultraviolet-induced skin damage. However, the role and mechanism by which wild chrysanthemum prevents UV-induced skin damage and photoaging have never been investigated in vitro. In the present study, we found that aqueous extracts from wild chrysanthemum strongly reduced high-dose UVB-induced acute cell death of human immortalized keratinocytic HaCat cells. Wild chrysanthemum extract was also demonstrated to reduce low-dose UVB-induced expression of the photoaging-related matrix metalloproteinases MMP-2 and MMP-9. The ROS level elevated by UVB irradiation was strongly attenuated by wild chrysanthemum extract. Further study revealed that wild chrysanthemum extract reduced UVB-triggered ERK1/2 and p38 MAPK phosphorylation and their protective role, which is partially dependent on inhibiting p38 activation. These results suggest that wild chrysanthemum extract can protect the skin from UVB-induced acute skin damage and photoaging by reducing the intracellular reactive oxygen species (ROS) level and inhibiting p38 MAPK phosphorylation. The present study confirmed the protective role of wild chrysanthemum against UV-induced skin disorders in vitro and indicated the possible mechanism. Further study to identify the active components in wild chrysanthemum extract would be useful for developing new drugs for preventing and treating skin diseases, including skin cancer and photoaging, induced by UV irradiation.
    Cytotechnology 07/2014; DOI:10.1007/s10616-014-9773-5 · 1.45 Impact Factor
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    ABSTRACT: Background Erysipelothrix rhusiopathiae is the causative agent of animal erysipelas and, to a fewer occurrences, human erysipeloid. It is ubiquitous in nature and commensal in diverse species of animals, wild or domestic, from mammals and birds to reptiles and fish. Mechanisms of its virulence and pathogenicity are poorly understood. Results Making use of the complete genome sequencing of E. rhusiopathiae strain SY1027 and comparative genome analysis between the three highly pathogenic strains (SY1027, Fujisawa and ATCC19414), the genomic structure and putative functional elements, such as pathogenicity island (PAI)-like regions, potential virulence factors and horizontal transferring genes of the bacteria are identified. Strain SY1027 genome is 1,752,910 base pairs long, just 30 kilobases smaller than strain Fujisawa, with the same GC level of 36.36%. It contains 1,845 open reading frames (ORF) predicted by GLIMMER 3.02, of which 1,775 were annotated by PGAAP, 1,757 (~95.23%) were annotated by NCBI nr blast, 1,209 by COG database and 1,076 by KEGG database. 37 potential virulence factors were annotated in strain SY1027 by VFDB, while 19 (~51.35%) of them are common in the 2 strains, 7 of which are potentially related to antibiotic resistance and highly conserved (~98-100% match identity (ID)) amongst the three strains of E. rhusiopathiae and modestly homologous to other gastrointestinal tract-inhabiting Firmicutes (~40% match ID), e.g. Clostridium spp., Enterococcus spp. Genomic island- and pathogenicity island-like regions were also predicted, in which some showed association with tRNA and potential virulence factors. Conclusion Complete genome sequencing of Erysipelothrix rhusiopathiae, the causative agent of animal erysipelas, was performed. Molecular identification of various genomic elements pave the way to the better understanding of mechanisms underlying metabolic capabilities, pathogenicity of swine erysipelas and prospective vaccine targets besides the widely used SpaA antigens.
    BMC Microbiology 07/2014; 14(1):176. DOI:10.1186/1471-2180-14-176 · 2.98 Impact Factor
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    ABSTRACT: Since October 2010, porcine diarrhea outbreaks have occurred widely, resulting in major losses in suckling piglets in China. A variant porcine epidemic diarrhea virus (PEDV), characterized by base deletion and insertion in the S gene, compared to classical PEDV CV777, was shown to be responsible for this outbreak. In this study, a multiplex TaqMan probe-based real-time PCR was developed for detecting PEDV and differentiating the variant from classical PEDV, by using two sets of primers and probes based on the S gene of PEDV. The limits of detection of both variant and classical PEDV were 5×10(2) DNA copies. Specificity was determined using eight other viral pathogens of swine. Reproducibility was evaluated using standard dilutions, with coefficients of variation <1.4%. Standard dilutions included in each test allowed quantification of the amount of PEDV. Among 42 intestinal samples from pigs with severe watery diarrhea, 36 variant PEDV and three classical PEDV samples were detected, with viral loads of 10(2)-10(8) copies/μl and 10(3)-10(5) copies/μl, respectively, which suggested that the variant PEDV was prevalent in China. The multiplex TaqMan probe-based real-time PCR should be a useful tool for quantifying viral load, detecting PEDV, and differentiating variant from classical PEDV.
    Journal of Virological Methods 06/2014; 206. DOI:10.1016/j.jviromet.2014.06.006 · 1.88 Impact Factor
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    ABSTRACT: Porcine circovirus type 2 (PCV2) has been identified as the etiologic agent which causing postweaning multisystemic wasting syndrome in swine farms in the world. Some quantitative proteomic studies showed that many proteins significantly changed in PCV2-infected cells. To explore the role of cellular chaperones during PCV2 infection, cytoprotective chaperone Hsp27 was analyzed in PCV2-infected PK-15 cells in this study. The results showed that Hsp27 could up-regulate and accumulate in phosphorylated forms in the nuclear zone during PCV2 replication. Suppression of Hsp27 phosphorylation with specific chemical inhibitors or downregulation of all forms of Hsp27 via RNA interference significantly reduced the virus replication. Meanwhile, over-expression of Hsp27 enhanced PCV2 genome replication and virion production. It indicated that Hsp27 was required for PCV2 production in PK-15 cells culture. It should be helpful for understanding the mechanism of replication and pathogenesis of PCV2 and development of novel antiviral therapies in the future.
    Virus Research 06/2014; DOI:10.1016/j.virusres.2014.05.024 · 2.83 Impact Factor
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    ABSTRACT: Porcine reproductive and respiratory syndrome virus (PRRSV) causes substantial economic losses to many swine-producing regions. In this study, PRRSV strain NT0801-F80 was derived from its parental isolate NT0801 by 80 passages in Marc-145 cells. Experimental infection of piglets clearly demonstrated that strain NT0801-F80 is less virulent than NT0801. However, whole genome sequencing showed that the genomes of the parental and attenuated strains are highly conserved compared with those of four other pairs of virulent parental/attenuated vaccine strains (VR2332 and RespPRRS MLV, JA142 and Ingelvac(®) ATP MLV, CH-1a and CH-1R, and JXA1 and JXAR). The attenuated strain NT0801-F80 has only 21 nucleotide changes, producing only 14 amino acid changes in NSP2, GP2, GP3, and GP5, compared with those aa sequences of the virulent parental strain. These mutated aa in the attenuated virus may be involved in virulence. These data provide valuable information on the attenuation mechanism of PRRSV that should be useful in future research.
    Virus Genes 05/2014; DOI:10.1007/s11262-014-1086-4 · 1.84 Impact Factor

Publication Stats

855 Citations
190.47 Total Impact Points

Institutions

  • 2007–2015
    • Nanjing Agricultural University
      Nan-ching, Jiangsu Sheng, China
  • 2010–2014
    • Kunming Institute of Zoology CAS
      • State Key Laboratory of Genetic Resources and Evolution
      Yün-nan, Yunnan, China
  • 2012
    • Nanjing Xiaozhuang University
      Nan-ching, Jiangsu Sheng, China
  • 2011
    • Kunming Medical College
      Yün-nan, Yunnan, China