Project description:We designed a long-term culture system for porcine intestinal organoids from intestinal crypt or single Lgr5+ stem cells by combining previously defined insights in the growth requirements of intestinal epithelium of human and mouse. We showed that long-term cultured swine intestinal organoids were expanded in vitro more than six months at least and maintained the potential to differentiate into different types of cells. These organoids were successfully infected with porcine enteric coronavirus including porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV). RNA-seq analysis showed that robust induction of transcripts associated with antiviral signaling in response to enteric coronavrius infection, including a number of interferon-stimulated genes and cytokines. Moreover, gene set enrichment analysis indicated that PEDV infection could suppress immune response in organoids. This 3D intestinal organoid model offers a long-term, renewable resource for investigating porcine intestinal infections with a variety of pathogens.
Project description:Innate immune response is the first line of antiviral defense resulting, in most cases, in pathogen clearance with minimal clinical consequences. Viruses have developed diverse strategies to evade innate immune response and to ensure their survival. Using transmissible gastroenteritis virus (TGEV) as a model, we previously reported that accessory gene 7 counteracts host antiviral response by its association with the catalytic subunit of protein phosphatase 1 (PP1c). A transcriptomic analysis was performed to further investigate the effect of gene 7 absence on the host cell. A recombinant TGEV virus lacking gene 7 expression (rTGEV-delta7) was previously generated in our laboratory. Porcine ST cells were mock infected or infected with wild type (rTGEV-wt) or mutant (rTGEV-delta7) virus. Gene expression was analyzed at 6 and 12 hours post infection (hpi) by using porcine Affymetrix microarray. Three biological replicates were made for each sample type.
Project description:Transmissible gastroenteritis virus (TGEV; Coronaviridae family) causes huge economic losses to the swine industry. MicroRNAs (miRNAs) play a regulatory role in viral infection and may be involved in the mammalian immune response. Here, we report a comprehensive analysis of host miRNA expression in TGEV-infected swine testis (ST) cells. Deep sequencing generated 3,704,353 and 2,763,665 reads from uninfected ST cells and infected ST cells, respectively. The reads were aligned to known Sus scrofa pre-miRNAs in miRBase 19, identifying 284 annotated miRNAs. Certain miRNAs were differentially regulated during TGEV infection, which confirmed the hypothesis that specific miRNAs play a regulatory role in virus-host interactions. 59 unique miRNAs displayed significant differentially expression between the normal and TGEV-infected ST cell samples: 15 miRNAs were significantly up-regulated and 44 were significantly down-regulated. Stem-loop RT-PCR was carried out to determine the expression levels of specific miRNAs in the two samples, and the results were consistent with those of sequencing. Gene ontology enrichment analysis of host target genes demonstrated that the differentially expressed miRNAs are involved in regulatory networks, including cellular process, metabolic process, immune system process. This is the first report of the identification of ST cell miRNAs and the comprehensive analysis of the miRNA regulatory mechanism during TGEV infection, which revealed the miRNA molecular regulatory mechanisms for the viral infection, expression of viral genes and the expression of immune-related genes. The results presented here will aid research on the prevention and treatment of viral diseases. 2 ST(Porcine testicular cells) cell samples, ST: normal ST cell sample (contro sample), TGEV: TGEV (Transmissible gastroenteritis virus) infected ST cell samples
