Primary goose kidney tubular epithelial cells for goose astrovirus genotype 2 infection: establishment and RNA sequencing analysis.

Goose astrovirus genotype 2 (GAstV-2) mainly causes gout in goslings; therefore, it is a major pathogen threatening to goose flocks. However, the mechanisms underlying host-GAstV-2 interactions remain unclear because host cells suitable for GAstV-2 replication have been unavailable. We previously noted that GAstV-2 is primarily located in goose renal epithelial cells, where it causes kidney damage. Therefore, here, we derived goose primary renal tubular epithelial (RTE) cells (GRTE cells) from the kidneys of goose embryos after collagenase I digestion. After culture in Dulbecco's modified Eagle medium/Nutrient mixture F-12 with 10% fetal bovine serum (FBS), the isolated cells had polygonal with roadstone-like morphology; they were identified to be epithelial cells based on the presence of cytokeratin 18 expression detected through immunofluorescence assay (IFA). GAstV-2 infection in GRTE cells led to no obvious cytopathic effects; the maximum amounts of infectious virions were observed 48 h post infection through IFA and quantitative PCR. Next, RNA-seq was performed to identify and map post-GAstV-2 infection differentially expressed genes. The downregulated pathways were mainly related to metabolism, including tryptophan metabolism, drug metabolism by cytochrome P450, xenobiotic metabolism by cytochrome P450, retinol metabolism, butanoate metabolism, starch and sucrose metabolism, ascorbate and aldarate metabolism, and drug metabolism by other enzymes and peroxisome. In contrast, the upregulated pathways were mostly related to the host cell defense and proliferation, including extracellular matrix-receptor interaction, complement and coagulation cascades, phagosome, PI3K-Akt signaling pathway, human T-lymphotropic virus 1 infection, lysosome, and tumor necrosis factor signaling pathway. In conclusion, we developed a GRTE cell line for GAstV-2 replication and analyzed the potential host-GAstV-2 interactions through RNA-seq; our results may aid in further investigating the pathogenic mechanisms underlying GAstV-2 infection and provide strategies for its prevention and control.