Effect of temperature oscillation on insect cell growth and baculovirus replication

Temperature oscillation can enhance cell viability of sf9 insect cells and baculovirus production of occlusion bodies (OB) and extracellular virus (ECV) compared with constant temperature in stationary culture and suspension culture. The optimal oscillation range was 24 to 28 degreesC. At this temperature oscillation, the viability of uninfected and infected sf9 cells can be maintained much longer than at 28 degreesC. Although the rate of virus infection was a little low at 24 to 28 degreesC, the final cell infectivity was similar to that at a constant temperature of 28 degreesC. The production of OB was increased from 13.4 to 17.4/cell in stationary culture and from 13.9/cell to 18.1/cell in suspension culture. The titer of ECV was increased from 87 to 114 PFU/cell in stationary culture and from 79 to 114 PFU/cell in suspension culture.