Development and characterization of a cell line from the embryos of half smooth tongue sole (Cynoglossus semilaevis)

A new cell line, CSEC, has been successfully established from embryos at gastrula stage of a cultured marine fish, half smooth tongue sole (Cynoglossus semilaevis). CSEC cells grow actively and stably more than 50 passages for over 200 d in DMEM medium supplemented with 15% FBS (fetal bovine serum), 2.5 ng/cm³ bFGF (basic fibroblast growth factor), 1 ng/cm³ LIF (leukemia inhibitory factor) and 50 mmol/dm³ 2-ME (2-mecaptoethanol). The cells grew well in the temperature range of 24-30℃ and the optimal growth temperature was 24℃. FBS and bFGF concentrations are the two key components for CSEC cells proliferation. Chromosome analysis reveals that CSEC cells have a normal diploid karyotype with 2n=42t. The significant fluorescent signals were observed in CSEC after transfection with the GFP reporter gene, suggesting that the CSEC cell line can be used as a useful tool for transgenic and genetic manipulation studies. CSEC cells showed the cytopathic effect (CPE) after infection with lymphosystis disease virus (LCDV) in 2 d. Moreover, the LCDV particles can be observed in the cytoplasm of virus-infected cells by electron microscopy. It suggests that CSEC could be potentially used for the study of aquatic virus.