The biopharmaceutical industry strives for greater efficiency in the production of biological drugs by using a larger number of clones in shorter development timelines, which allows for better production cell lines and higher production yields. The previously used shake flasks (SF) are being replaced by 24-deep well plates (24DW) and 96-deep well plates (96DW). The aim of this master's thesis is to evaluate the impact of different transfection platforms (classical - LT and high-throughput 96W platform - HT) on the growth conditions of CHO cells and the titer of recombinant antibodies, as well as to assess the HT technology for the selection of stably transfected CHO cells in 24DW and 96DW cultivation platforms. The expression efficiency of inserted genes affecting antibody glycosylation was evaluated by mRNA analysis. When comparing viability at the selection crisis point in 24DW and 96DW, the following p-values were obtained: < 0.0001 (cell line 1), 0.1365 (cell line 2), and 0.0002 (cell line 3). Selection was more stressful for cells in 96DW compared to 24DW. The HT transfection method resulted in greater variability of viability in cell lines 1 and 2. In cell line 3, comparable average viabilities (p = 0.6916) were obtained between LT and HT. In fed-batch culture, comparable titers were obtained on day 7 and partially comparable titers on day 14 between 24DW and 96DW, as well as between LT and HT. Very similar maximum titers were achieved with each platform. The highest specific productivity was obtained with 96DW HT. It was demonstrated that additional genes for glycosylation regulation (GE genes) could be the reason for lower titers and viable cell density (VCD). Different transfection methods did not affect the expression of those genes (gene A, p = 0.1425; gene B, p = 0.0777), while lower expression was observed in 96DW compared to 24DW (gene A, p < 0.0001; gene B, p < 0.0001).
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