Identification and characterization of linear B cell epitopes on the nucleocapsid protein of porcine epidemic diarrhea virus using monoclonal antibodies.

The nucleocapsid (N) protein of porcine epidemic diarrhea virus (PEDV), the most important pathogen causing severe diarrhea in piglets, is a highly conserved structural protein. In this study, 5 monoclonal antibodies (McAbs) against the PEDV N-protein were prepared and identified. Three new epitopes, QIRWRMRRGERI, GYAQIASLAPNVAALLFGGNVA VRE and HEEAIYDDV, were firstly identified in the viral N-protein, by using McAbs 3F10, 6A11, and 1C9.

Pathogenicity and immunogenicity of a new strain of porcine epidemic diarrhea virus containing a novel deletion in the N gene.

Since late 2010, highly virulent PEDV G2-genotype strains have emerged globally extracting heavy losses on the pork industries of numerous countries. We investigated the characteristics of a field strain of PEDV (PEDV strain SH) isolated from a piglet with severe diarrhea on a farm in Shanghai China. Whole genome sequencing and analysis revealed that the SH strain belonged to subtype G2b and has a unique 12-aa deletion (aa 399-410) including the antigenic epitope NEP-1C9 (aa 398-406) of the N protein.

Highly efficient cellular uptake of a cell-penetrating peptide (CPP) derived from the capsid protein of porcine circovirus type 2.

Porcine circovirus type 2 (PCV2) is one of the smallest, nonenveloped, single-stranded DNA viruses. The PCV2 capsid protein (Cap) is the sole viral structural protein and main antigenic determinant. Previous sequence analysis has revealed that the N terminus of the PCV2 Cap contains a nuclear localization signal (NLS) enriched in positively charged residues.

Optimized conditions for preserving stability and integrity of porcine circovirus type2 virus-like particles during long-term storage.

Although porcine circovirus type 2 (PCV2) virus-like particles (VLPs) have been successfully harvested from various protein expression systems, conditions to promote their stability and integrity during long-term storage have not been well defined since only the intact VLPs, instead of the monomeric capsid protein (Cap), can induce neutralizing antibodies in pigs in previous studies. In this study, freshly prepared PCV2 VLPs were stored in several media (various concentrations of NaCl, sorbitol, sucrose and trehalose) at three temperatures (4°C, -20°C and -80°C) and their stability and integration were evaluated after 7 month. Addition of 15% trehalose in storage buffer promoted long-term preservation of PCV2 VLPs.

Detecting time-dependent coherence between non-stationary electrophysiological signals--a combined statistical and time-frequency approach.

Various time-frequency methods have been used to study time-varying properties of non-stationary neurophysiological signals. In the present study, a time-frequency coherence estimate using continuous wavelet transform (CWT) together with its confidence intervals are proposed to evaluate the correlation between two non-stationary processes. The approach is based on averaging over repeat trials.