The porcine epidemic diarrhea virus (PEDV) is a member of the coronavirus family, causing deadly watery diarrhea in newborn piglets. The global pandemic of PEDV, with significant morbidity and mortality, poses a huge threat to the swine industry. The currently developed vaccines and drugs are only effective against the classic GI strains that were prevalent before 2010, while there is no effective control against the GII variant strains that are currently a global pandemic. In this review, we summarize the latest progress in the biology of PEDV, including its transmission and origin, structure and function, evolution, and virus–host interaction, in an attempt to find the potential virulence factors influencing PEDV pathogenesis. We conclude with the mechanism by which PEDV components antagonize the immune responses of the virus, and the role of host factors in virus infection. Essentially, this review serves as a valuable reference for the development of attenuated virus vaccines and the potential of host factors as antiviral targets for the prevention and control of PEDV infection.

Transgenic pigs play an important role in producing higher quality food in agriculture and improving human health when used as animal models for various human diseases in biomedicine. Production of transgenic pigs, however, is a lengthy and inefficient process that hinders research using pig models. Recent applications of the CRISPR/Cas9 system for generating site-specific gene knockout/knockin models, including a knockout pig model, have significantly accelerated the animal model field. However, a knockin pig model containing a site-specific transgene insertion that can be passed on to its offspring remains lacking. Here, we describe for the first time the generation of a site-specific knockin pig model using a combination of CRISPR/Cas9 and somatic cell nuclear transfer. We also report a new genomic “safe harbor” locus, named pH11, which enables stable and robust transgene expression. Our results indicate that our CRISPR/Cas9 knockin system allows highly efficient gene insertion at the pH11 locus of up to 54% using drug selection and 6% without drug selection. We successfully inserted a gene fragment larger than 9 kb at the pH11 locus using the CRISPR/Cas9 system. Our data also confirm that the gene inserted into the pH11 locus is highly expressed in cells, embryos and animals.

Classical swine fever (CSF) caused by classical swine fever virus (CSFV) is one of the most detrimental diseases, and leads to significant economic losses in the swine industry. Despite efforts by many government authorities to stamp out the disease from national pig populations, the disease remains widespread. Here, antiviral small hairpin RNAs (shRNAs) were selected and then inserted at the porcine Rosa26 (pRosa26) locus via a CRISPR/Cas9-mediated knock-in strategy. Finally, anti-CSFV transgenic (TG) pigs were produced by somatic nuclear transfer (SCNT). Notably, in vitro and in vivo viral challenge assays further demonstrated that these TG pigs could effectively limit the replication of CSFV and reduce CSFV-associated clinical signs and mortality, and disease resistance could be stably transmitted to the F1-generation. Altogether, our work demonstrated that RNA interference (RNAi) technology combining CRISPR/Cas9 technology offered the possibility to produce TG animal with improved resistance to viral infection. The use of these TG pigs can reduce CSF-related economic losses and this antiviral strategy may be useful for future antiviral research. Classical swine fever (CSF), caused by classical swine fever virus (CSFV), and is a highly contagious, often fatal porcine disease that causes significant economic losses. Due to the economic importance of this virus to the pig industry, the biology and pathogenesis of CSFV have been investigated extensively. Despite efforts by many government authorities to stamp out the disease from national pig populations, the disease remains widespread, and it is only a matter of time before the virus is reintroduced and the next round of disease outbreaks occurs. These findings highlight the necessity and urgency for developing effective approaches to eradicate the challenging CSFV. In this study, we successfully produced anti-CSFV TG pigs by combining RNAi technology and CRISPR/Cas9 technologies, and viral challenge results confirmed that these TG pigs could effectively limit the replication of CSFV in vivo and in vitro. Additionally, we confirmed that the disease resistance traits in the TG founders were stably transmitted to their F1-generation offspring. Altogether, our work reported the combinational application of CRISPR/Cas9 and RNA interference (RNAi) technology in the generation of anti-CSFV TG pigs, it provided an alternative strategy to change the virus. The results of this study suggested that these TG pigs offered potential benefits over commercial vaccination and reduced CSFV-related economic losses.

Transmissible gastroenteritis virus (TGEV) is a member of the alphacoronavirus genus, which has caused huge threats and losses to pig husbandry with a 100% mortality in infected piglets. TGEV is observed to be recombining and evolving unstoppably in recent years, with some of these recombinant strains spreading across species, which makes the detection and prevention of TGEV more complex. This paper reviews and discusses the basic biological properties of TGEV, factors affecting virulence, viral receptors, and the latest research advances in TGEV infection-induced apoptosis and autophagy to improve understanding of the current status of TGEV and related research processes. We also highlight a possible risk of TGEV being zoonotic, which could be evidenced by the detection of CCoV-HuPn-2018 in humans.

Background: There is increasing evidence that long non-coding RNAs (lncRNAs) are involved in the process of carcinogenesis and treatment using chemotherapy. Pterostilbene, a phytochemical agent with natural antioxidant and anti-inflammatory properties, has been shown to modulate oncogenic processes in many cancers. However, there has been limited research on the association between pterostilbene and the expression of lncRNAs. Methods: MCF7 breast cancer cells were treated with various concentrations of pterostilbene and their gene expression profile was analyzed by quantitative real-time PCR, Western blotting and immunofluorescence. Results: Treatment with pterostilbene inhibited cell proliferation and epithelial-to-mesenchymal transition (EMT), and increased cell apoptosis, autophagy and ER stress. The Akt/mTOR pathway was downregulated, but p38 MAPK/Erk signaling was activated in cells following treatment with pterostilbene. Pterostilbene increased the expression of the lncRNAs MEG3, TUG1, H19, and DICER1-AS1 whereas the expression of LINC01121, PTTG3P, and HOTAIR declined. Knockdown of lncRNA H19 resulted in a reduction of the cell invasion, with the cells becoming more sensitive to pterostilbene therapy. Conclusions: These results suggest that efficient optimum disruption of lncRNA expression might possibly improve the anti-tumor effects of phytochemical agents, thus serving as a potential therapy for breast cancer.