Development and characterization of a new cell line derived from European eel <i>Anguilla anguilla</i> kidney

Abstract

A new cell line derived from the kidney of European eel, <i>Anguilla anguilla</i>, has been established and characterized. This cell line, designated as EK (eel kidney), has been maintained in Leibovitz's L-15 supplemented with 10% fetal bovine serum for over 24 months, and subcultured more than 60 times. This cell line consists predominantly of fibroblast-like cells, and can grow at 15-37°C under an optimum temperature of 26°C. The origin of this cell line was confirmed by polymerase chain reaction (PCR) amplification and <i>18s</i> recombinant (r)RNA sequencing. The chromosome analysis of EK cells at passage 58 revealed an ananeuploid karyotype. The EK cells were successfully transfected with the Pegfp-N1 plasmid, suggesting its potential in genetic studies. The susceptibility test showed a significant cytopathic effect (CPE) in EK cells for <i>Rana grylio</i> virus, and the viral replication was evidenced with quantitative real-time PCR (qRT-PCR) assay. After poly (I:C) stimulation, the expression of the immune-related molecules including interferon regulatory factor-3 (<i>irf3</i>), interferon regulatory factor-7 (<i>irf7</i>) and cytochrome P450 (<i>CYP</i>450) were significantly upregulated in EK cells, while the expression of transforming growth factor (TGF-<i>β</i>) was downregulated. These results suggested the potential of EK cell line as a model in gene engineering, virus identification and environmental toxicology.