Publications by authors named "Xin-yuan Qiao"
Article Synopsis
- A new method was developed for detecting five types of viruses (astrovirus, rotavirus, norovirus, sapovirus, and enteric adenovirus) linked to acute enteritis.
- The method combines dual priming oligonucleotide (DPO) technology with high-performance liquid chromatography (HPLC) analysis, resulting in higher sensitivity compared to traditional methods like agarose gel electrophoresis.
- This assay demonstrated 100% specificity and sensitivity ranging from 96% to 100%, highlighting its potential for accurate diagnosis of enteric virus infections.
A loop-mediated isothermal amplification (LAMP) assay was developed for detection of bovine parvovirus (BPV) DNA. Four primers were designed to recognize six distinct regions on the target DNA based on a highly conserved sequence in the VP2 region of the BPV genome. The optimized LAMP reaction conditions were 8 mM Mg²⁺, 1.
View Article and Find Full Text PDFInfectious pancreatic necrosis virus (IPNV) infects wild and cultured salmonids, causing high mortality in juvenile trouts and salmons. IPNV VP2-VP3 fusion gene was constructed by splicing overlap extension (SOE) PCR and inserted into Lactobacillus/Escherichia coli shuttle vectors (pPG1and pPG2) followed by transformation of Lactobacillus casei competent cell to yield two recombinant strains: Lc:PG1-VP2-VP3 (surface-displayed) and Lc:PG2-VP2-VP3 (secretory). Subsequently, juvenile rainbow trouts were inoculated with the recombinant strains via orogastric route.
View Article and Find Full Text PDFArticle Synopsis
- Infectious pancreatic necrosis virus (IPNV) poses a significant threat to salmonid fish, leading to high mortality rates and considerable economic losses in aquaculture.
- Lactobacillus strains are being explored as effective vehicles for delivering vaccines, with two recombinant strains, Lc:PG1-VP2 and Lc:PG2-VP2, created to present the IPNV capsid gene in rainbow trout.
- The study found that Lc:PG2-VP2 prompted a stronger immune response compared to other strains, resulting in a substantial reduction of virus loads in infected fish, making it a promising candidate for a live vaccine against IPNV.
Article Synopsis
- Researchers created effective mucosal vaccine formulations against porcine epidemic diarrhea virus (PEDV) by inserting DNA fragments for the spike protein (S1) and nucleocapsid (N) into specific plasmids and transforming them into Lactobacillus casei (Lc), resulting in four recombinant strains.
- When administered orally, the combination of live Lc expressing both S1 and N proteins triggered significantly stronger immune responses compared to either protein alone, although not as strong as the N protein alone.
- The study found that the surface-displayed combination (PG1-S1 + PG1-N) had better immunogenicity and PEDV-neutralizing activity than the secretory mixture (PG2-S1 + PG2-N), with
This study explored the feasibility of Lactobacillus pentosus as a live vehicle to deliver and express antigen. First of all, L. pentosus transformed by electroporation with the plasmids pg611-6D (anchored) and pg612-6D (secretory) based on the xylose operon generated the recombinant strains rLppg611-6D and rLppg612-6D, respectively, expressing the D antigenic site of the spike (S) protein of Transmissible gastroenteritis virus (TGEV), for intragastric administration in mice.
View Article and Find Full Text PDFPorcine epidemic diarrhea virus (PEDV) LJB/03 strain was isolated from the feces of piglets suspected to be suffering from a severe diarrhea in Heilongjiang Province, and was identified by immunofluorescence test, immunelectronmicroscopy, RT-PCR and indirect ELISA assay. Characteristics of the virus culture and the methods of improvement of virus titer were explored. The results showed that the virus had the typical appearance of the coronavirus.
View Article and Find Full Text PDFThe objective of this study to design a delivery system resistant to the gastrointestinal environment for oral vaccine against porcine rotavirus. Lactococcus lactis NZ9000 was transformed with segments of vP4 of the porcine rotavirus inserted into the pNZ8112 surface-expression vector, and a recombinant L. lactis expressing VP4 protein was constructed.
View Article and Find Full Text PDF[The surface display of porcine parvovirus VP2 protein in Lactobacillus casei].
Sheng Wu Gong Cheng Xue Bao
March 2007
Lactobacillus casei 393 was selected as a bacterial carrier for the expression of Porcine Parvovirus (PPV) protective antigen VP2 protein. The gene encoding PPV VP2 protein was cloned into the Lactobacillus casei surface expression vector pPG, and then the constructed recombinant vector pPG-VP2 was electrotransformed into Lactobacillus casei 393 generating the recombinant system pPG-VP2/L. casei393 expressing PPV VP2 protein.
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