Figure 1 The effect of temperature downshift on the performance of CHO-K1 HP and CHO-K1 LP shake flask cultures. (●, black) LP constant temperature, (■, pink) HP constant temperature, (▼, green) LP temperature downshift, and (▲, purple) HP temperature downshift. The temperature was downshifted from 37°C to 33°C on day 5 (vertical dashed line). (a) Viable cell density. (b) Cell viability. (c) Antibody titer. (d) Cell specific antibody production rate. (e) Significance analysis of final antibody titer. (f) Significance analysis of antibody-specific production rate. (g) Daily percentage of LP CHO cell cycle. (h) Daily percentage of HP CHO cell cycle. Samples were taken at 24-h intervals and experimental values represent three biological replicates ± SD. Two-tailed Student’s t-test was conducted using GraphPad Prism 8.0 ((*) p < 0.05, (**) p < 0.01, (***) p < 0.001 and (****) p < 0.0001).