Cell Culture of Rainbow Trout Liver

Abstract

The primary cultures of rainbow trout fry liver cells were performed in TC199 medium sup-plemented with 10% fetal bovine serum and with 10ng/ml of epidermal growth factor (EGF) and/or 40 nM of insulin. Epithelial cells grown in a flask supplemented with EGF and insulin, designated RTL-4, could be transferred at the 40th day of the primary culture and have been subcultured 40 times. The cells got fast doubling time gradually, and were able to be transferred at intervals of 7-10 days. RTL-4 cells grow in the manner of contact inhibited monolayer and consist of large epithelial cells with a round nucleus and abundant granular organella. Electron microscopically, most of the cells were large and round with a round nucleus having a large electron-dense nucleolus at the center of nucleus and had well developed rough surfaced endoplasmic reticulum and mitochondria which are the principle morphological properties of liver cells. Some of the cells were weakly PAS positive. RTL-4 cells had as high a susceptibility to IPNV as that of SE-A10 cells, when examined by plaque assay. And the cells had a tenth or less susceptibility to IHNV than that of SE-A10 cells.