Assessment of hemagglutination activity of porcine deltacoronavirus

Porcine deltacoronavirus induces mitochondrial apoptosis in ST cells / 生物工程学报

Porcine deltacoronavirus (PDCoV) is a newly emerging enteropathogenic swine coronavirus causing acute diarrhea and vomiting in pigs. The apoptosis of ST cells induced by PDCoV infection was studied in this research. In ST cells, caspase activity assay showed that the activity of caspase 3, caspase 8 and caspase 9 increased significantly with the infection of PDCoV, but not observed in UV irradiated PDCoV-infected cells, indicating that PDCoV infection activated both endogenous and exogenous apoptotic pathways in ST cells, and the induction of apoptosis depended on viral replication. To further investigate the endogenous apoptosis induced by PDCoV, cytochrome C and apoptosis-inducing factors in cytoplasm and mitochondria were detected. Compared with normal cells, the amount of cytochrome C released from mitochondria to cytoplasm increased significantly in PDCoV-infected cells, and the release increased with the prolongation of infection, while the apoptosis-inducing factor was always localized to mitochondria, suggesting that PDCoV induced apoptosis was initiated through caspase-dependent mitochondrial apoptosis pathway by promoting cytochrome C in the mitochondrial membrane gap into the cytosol. In conclusion, this study reveals the mechanism of PDCoV inducing apoptosis.

Isolation and characterization of Korean porcine deltacoronavirus strain KNU16-07

Porcine deltacoronavirus (PDCoV) has emerged in several pig-raising countries and has been a causative pathogen associated with diarrheal diseases in South Korea since 2014. In the present study, we were able to isolate and cultivate a Korean PDCoV strain (KNU16-07) in cell culture and investigate its pathogenicity. PDCoV-inoculated piglets showed watery diarrhea accompanied by acute enteritis in the natural host. Sequencing analysis demonstrated the genetic stability of KNU16-07 for at least thirty serial passages.

Development and application of real-time RT-PCR and S1 protein-based indirect ELISA for porcine deltacoronavirus / 生物工程学报

Porcine deltacoronavirus (PDCoV) has been recently recognized as an emerging viral pathogen that causes diarrhea in newborn piglets. A total of 254 small intestinal or fecal samples collected from 10 provinces including Henan, Hunan, Zhejiang, Jiangxi, Anhui, Hebei, Heilongjiang, Jiangsu, Shandong and Shanghai between 2014 and 2015, were screened by quantitative RT-PCR targeting the viral M gene. Eleven PDCoV positive samples were identified with a total positive rate of 4.33%. An indirect enzyme-linked immunosorbent assay (ELISA) was developed based on the recombinant S1 protein of PDCoV. This assay was used to test 609 serum samples of pigs with diarrhea symptoms collected from 10 provinces between 2015 and 2016. The positive rate of PDCoV antibody was 44.17% (269/609). The two methods can be used to monitor the PDCoV epidemiology in the levels of PDCoV specific RNA or antibody, helping better prevent and control PDCoV.

A simple and rapid identification method for newly emerged porcine Deltacoronavirus with loop-mediated isothermal amplification

BACKGROUND: Porcine Deltacoronavirus (PDCoV) is a newly emerged enteropathogenic coronavirus that causes diarrhea and mortality in neonatal piglets. PDCoV has spread to many countries around the world, leading to significant economic losses in the pork industry. Therefore, a rapid and sensitive method for detection of PDCoV in clinical samples is urgently needed. RESULTS: In this study, we developed a single-tube one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay specific for nucleocapsid gene to diagnose and monitor PDCoV infections. The detection limit of RT-LAMP assay was 1 × 101 copies of PDCoV, which was approximately 100-fold more sensitive than gel-based one-step reverse transcription polymerase chain reaction (RT-PCR). This assay could specifically amplify PDCoV and had no cross amplification with porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine kobuvirus (PKoV), porcine astrovirus (PAstV), porcine reproductive and respiratory syndrome virus (PRRSV), classic swine fever virus (CSFV), and porcine circovirus type 2 (PCV2). By screening a panel of clinical specimens (N = 192), this method presented a similar sensitivity with nested RT-PCR and was 1-2 log more sensitive than conventional RT-PCR in detection of PDCoV. CONCLUSIONS: The RT-LAMP assay established in this study is a potentially valuable tool, especially in low-resource laboratories and filed settings, for a rapid diagnosis, surveillance, and molecular epidemiology investigation of PDCoV infections. To the best of our knowledge, this is the first work for detection of newly emerged PDCoV with LAMP technology.