Background: Transient Gene Expression (TGE) gained popularity over the last decade as a rapid method for the production of milligram to gram quantities of recombinant proteins for preclinical studies in biophama industry. Thereby, the optimization of the TGE technique for Chinese hamster ovary (CHO) as the dominant host for the production of biotherapeutics is of great interest to reach the values for Human Embryo Kidney-293 (HEK-293) cells in terms of transfection efficiencies and production titers. TGE efficiencies are cell line and vector dependant.
Methods: In transfection efficiency optimization experiments, different starting cell densities, different amounts of plasmid DNA and PEI transfection reagent were investigated to achieve the best conditions leading to maximum transfection efficiencies. Furthermore, in order to investigate the effect of peptone feeding on transfection efficiency, three different sources of peptones with the greatest effect in the CD DG44 basal media were selected; Casein Tryptone N1, Soy petone A2SC and Soy peptone E110.
Results: The transfection strategy performed here was able to make an outstanding increase in transfection efficiency of CHO DG44 cell line transfected with pTracer-SV40-mutated t-PA plasmid from 3.6% in our starting non-optimized condition to 66.93% in finally optimized situation. Moreover, peptone feeding strategy used here was successful to increase volumetric productivities up to 37%. In addition, the amounts of both PEI and plasmid DNA were reduced up to 66% and 25%, respectively compared to our previous protocol.
Conclusion: Here we described an optimization process for TGE in suspension-adapted CHO cells based on Polyethylenimine (PEI)/DNA concentration, DNA: PEI ratio, starting cell densities and peptone feeding strategy.
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Bioresour Technol
June 2024
Centre for Technology in Water and Wastewater, University of Technology, Sydney NSW 2007, Australia.
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February 2024
Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India.
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October 2023
Department of Environmental Engineering, National Cheng Kung University, No. 1, University Road, Tainan, 701, Taiwan; Sustainable Environment Research Laboratory (SERL), National Cheng Kung University, No. 1, University Road, Tainan, 701, Taiwan. Electronic address:
In this study, a mixed-cultural metabolic network for anaerobic digestion that included the concept of a "universal bacterium" was constructed, and metabolic flux analysis (MFA) applying this network was conducted to evaluate the flow of electrons and materials during H fermentation under various conditions. The MFA results from two H fermenters feeding glucose with (GP) or without (GA) the addition of peptone suggest that hydraulic retention time (HRT) presents a significant impact on hydrogen production, and the reversed trends could be observed at HRTs below and above 4 h. From the MFA results of lactate/acetate-fed H fermenter, the highest flux of H production is associated with more significant acetate consumption and the following pathways toward the anaplerotic reactions cycle that produces NADH.
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March 2023
Marmara University, School of Medicine, Department of Physiology, İstanbul, Turkey. Electronic address:
Neuropeptide W (NPW), a novel hypothalamic peptide, contributes to the central regulation of food intake and energy balance, and suppresses feeding behavior when administered centrally. The aim of our study was to investigate the role of peripherally administered NPW in the modulation of gastric emptying, and to evaluate the participation of afferent fibers, cholecystokinin (CCK) receptors and gastric smooth muscle contractility in the regulatory effects of NPW on gastric motility. In Sprague-Dawley male rats equipped with gastric fistula, gastric emptying rate of the saline and peptone solutions was measured following subcutaneous administration of NPW (0.
View Article and Find Full Text PDFN Z Vet J
July 2022
Epilab, School of Veterinary Science, Massey University, Palmerston North, New Zealand.
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