Establishment and characterization of a new marine fish cell line derived from red-spotted grouper Epinephelus akaara

A new marine fish cell line, EAGL, derived from the liver of red‐spotted grouper Epinephelus akaara was established and characterized. The cells multiplied well in minimum essential medium (MEM) supplemented with 10% foetal bovine serum (FBS) at temperatures between 25 and 30° C. The growth rate of this cell line increased as the proportion of FBS increased from 5 to 20% at 25° C, with maximum growth at the concentration of 15 or 20% FBS. Morphologically, the cells were epithelial‐like and the presence of pancytokeratin confirmed their epithelial origin. Chromosome analysis revealed that the modal chromosome number was 48. The susceptibility of the cell line to four fish viruses was tested. Significant cytopathic effect (CPE) was only observed in Singapore grouper iridovirus (SGIV)‐infected cells, and the virus replication was further confirmed by immunofluorescence, electron microscopy and real‐time reverse‐transcription (RT)‐PCR assay. When the cells were transfected with pEGFP‐N3 plasmid, bright fluorescent signals were observed, suggesting that this cell line can be used for transgenic and genetic manipulation studies.