Publications by authors named "Zhifen Wen"

Porcine epidemic diarrhea virus (PEDV) infects pigs of all ages by invading villous epithelial cells of the small intestine causing severe diarrhea with high mortality rate in suckling piglets. Mucosal immunity is believed to play an important role in PEDV control and mucosal delivery of vaccines induces mucosal immunity more efficiently than parenteral vaccination. In this study, coated PEDV-loaded microspheres with the size range of 700-900 μm in diameter were developed by centrifugal granulation-fluidized bed coating and demonstrated as an effective oral delivery system to protect PEDV antigens against the complex gastrointestinal environment by detecting the live virus particles in microspheres after the simulated gastric fluid treatment and the PEDV RNA in fecal swabs collected from all weaned piglets (100%) orally inoculated with coated PEDV-loaded microspheres.

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PEDV variants, causing severe diarrhea in neonatal suckling piglets with a mortality rate up to 100%, have being epidemic since late 2010 in china. To meet the pressing need of safe and cost-efficient PED maternal vaccines against PEDV variant, we vaccinated growing piglets with a flagellin-adjuvanted PED vaccine rSF-COE-3D by injection at Houhai acupoint. The vaccination not only enhanced the antibody responses of serum IgG/IgA, mucosal IgA and serum neutralizing antibody, but also improved the production of IFN-γ and IL-4.

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Porcine epidemic diarrhea (PED) is an important re-emergent infectious disease and inflicts huge economic losses to the swine industry worldwide. To meet the pressing need of developing a safe and cost-efficient PED maternal vaccine, we generated three PED subunit vaccine candidates, using recombined Salmonella flagellin (rSF) as a mucosal molecular adjuvant. Domain D3 in rSF was replaced with COE domain of PEDV to generate rSF-COE-3D.

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Since 2010, variant strains of porcine epidemic diarrhea virus (PEDV) have caused disasters in the pork industry. The spike (S) protein, as the major immunity-eliciting antigen, has previously been used for serological testing and has been found to correlate significantly with the results of the serum neutralization (SN) test. However, further evaluation of this method is needed as new epidemic strains of PEDV emerge.

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We identified from suckling piglets with diarrhea in China a new bat-HKU2-like porcine coronavirus (porcine enteric alphacoronavirus). The GDS04 strain of this coronavirus shares high aa identities (>90%) with the reported bat-HKU2 strains in Coronaviridae-wide conserved domains, suggesting that the GDS04 strain belongs to the same species as HKU2.

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Influenza A H7N9 virus is the latest emerging pandemic threat, and has rapidly diverged into three clades, demanding a H7N9 virus vaccine with broadened protection against unmatched strains. Hemagglutinin (HA)-based structural design approaches for stabilizing HA proteins have provided excitingly promising results. However, none of the HA-based structural design approaches has been applied to a recombinant replicative influenza virus.

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