Cowger N L, O'Connor K C, Bivins J E
Department of Chemical Engineering, Tulane University, New Orleans, Louisiana, USA.
Enzyme Microb Technol. 1997 Apr;20(5):326-32. doi: 10.1016/s0141-0229(96)00153-6.
Simulated microgravity within the NASA High Aspect Rotating-Wall Vessel (HARV) provides a quiescent environment to culture fragile insect cells. In this vessel, the duration of stationary and death phase for cultures of Spodoptera frugiperda cells was greatly extended over that achieved in shaker-flask controls. For both HARV and control cultures, S. frugiperda cells grew to concentrations in excess of 1 x 10(7) viable cells ml-1 with viabilities greater than 90%. In the HARV, stationary phase was maintained 9-15 days in contrast to 4-5 days in the shaker flask. Furthermore, the rate of cell death was reduced in the HARV by a factor of 20-90 relative to the control culture and was characterized with a death rate constant of 0.01-0.02 day-1. Beginning in the stationary phase and continuing in the death phase, there was a significant decrease in population size in the HARV versus an increase in the shaker flask. This phenomenon could represent cell adaptation to simulated microgravity and/or a change in the ratio of apoptotic to necrotic cells. Differences observed in this research between the HARV and its control were attributed to a reduction in hydrodynamic forces in the microgravity vessel.
美国国家航空航天局高长宽比旋转壁式生物反应器（HARV）内的模拟微重力为培养脆弱的昆虫细胞提供了一个静态环境。在这个生物反应器中，草地贪夜蛾细胞培养的静止期和死亡期的持续时间比摇瓶对照中的长得多。对于HARV和对照培养物，草地贪夜蛾细胞均生长至浓度超过1×10⁷个活细胞/毫升，活力大于90%。在HARV中，静止期维持9 - 15天，而在摇瓶中为4 - 5天。此外，相对于对照培养物，HARV中的细胞死亡率降低了20 - 90倍，其特征是死亡率常数为0.01 - 0.02天⁻¹。从静止期开始并持续到死亡期，HARV中的种群数量显著减少，而摇瓶中的种群数量增加。这种现象可能代表细胞对模拟微重力的适应和/或凋亡细胞与坏死细胞比例的变化。本研究中观察到的HARV与其对照之间的差异归因于微重力生物反应器中流体动力的降低。
