Mass cultivation of marine fish Chinook salmon embryo cells in bioreactor with low-serum medium

Mass cultivation of marine fish cells is the key step of killed virus vaccine preparation for preventing mariculture fishes from virus infection. In the low-serum culture of Chinook salmon embryo cells (CHSE), the optimal glucose (1-5 mmol/L) and glutamine (0-0.6 mmol/L) concentrations were determined and the culture technique of medium-exchange was established in the basis on the understanding of cell growth and metabolism features. CHSE cells attached on microcarriers were inoculated into 1.5-L bioreactor at 6.5×105 cells/mL and the cells of 2.3×106 cells/mL in mid logarithmic phase at 9 days were successfully transferred to a 5-L disk packed-bed bioreactor at the density of 5.3×105 cells/mL. A cell density of 5.9×106 cells/mL was achieved at 22 days in the packed-bed bioreactor using medium-exchange culture to control nutrient and byproduct concentrations away from inhibitory levels. In addition, cell density in packed-bed bioreactor was successfully estimated by the glucose consumption kinetics. This work laid the foundations for large-scale preparation of viruses by CHSE cells as host.