Intensified fed-batch bioprocess is a bioprocess in which we increase the inoculation concentration of viable cells in the production (N) stage of the process, in which it is necessary to achieve a sufficiently high concentration of viable cells in the pre-production (N-1) stage. Here, this can be achieved in two ways, either by using highly enriched growth media and feeding media, or by perfusion. In our experiment, we used the latter, obtaining a sufficiently high concentration of viable cells to be able to inoculate the production bioreactors with 5.0 and 10.0 x 106 viable cells/mL (10x and 20x more than the reference process). With the introduction of the pre-production stage, we shifted the growth stage, which is mostly non-production, to pre-production stage. At the same time, perfusion was used to get rid of significant amounts of lactate and ammonia, which are by-products of metabolism and cause growth inhibition. As a result, higher maximum concentrations of viable cells were achieved in the production stage. Moreover, it was reached between 5 and 7 days earlier. In addition, we were also interested in the effect of different initial concentrations of living cells on the production process. We also studied the effect of various additives in the feeding medium on the titer and product quality (mAb), namely added AA, Na2HPO4, galactose and Mn. Our main goal was to achieve the same titer with the same quality earlier compared to the reference process and thus shorten the production stage of the bioprocess. We found that this was achieved between 5 and 6 days earlier, and that at the end of the bioprocess the titer was higher between 1.5x and 2.0x compared to the reference process. In terms of quality, we focused on glycan profiles, which were on different days of bioprocess compared with the reference process on day 14. Here, different deviations and trends of changes were observed.
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