Induction of the autophagy pathway enhances antibody productivity in fed-batch cultures
Since the most common culture systems found in industry are fed-batch cultures, the ability of the AIP to enhance protein production was also evaluated on this culture platform. CHO-aIL-1β cells were cultured in the presence or absence of AIP using fed-batch and the production of IgG was evaluated by ELISA. Figure 3 shows the specific and volumetric productivity in AIP-treated and control (0 µM peptide) cultures. The specific productivity increased from 9.6 ± 1.5 µg/106cells/day in control cultures up to 13.7 ± 0.6 µg/106cells/day in AIP-treated cultures. The increase in specific productivity above that of controls was statistically significant in 2 and 4 µM AIP-containing cultures (ANOVA, P < 0.05). The volumetric productivity also increased significantly (ANOVA, P < 0.05) to 1260.1 ± 87.1 and 1229.7 ± 90.0 µg/mL in cultures with 3 and 4 µM AIP concentrations, so by over 2-fold compared to the control cultures. These findings are consistent with those obtained in batch cultures, but with the volumetric productivity increase over twice as much as the 46% increase observed in batch culture.