However, under our conditions, EGCG addition was not effective when it was added at the intermediate point of culture, but it was effective when it was added on the first day of culture. in cells cultured in EGCG-containing media, which may be suggesting that there was less stress in the culture environment. Additionally, EGCG did not affect the N-glycan quality of IgG1. Our results indicated that adding EGCG only on the first day of the culture enhanced the specific productivity and total amount of recombinant protein production in batch cultures. This approach may prove to be useful for biopharmaceutical production. Keywords:Chinese hamster ovary cells, ()-Epigallocatechin-3-gallate, Natural compound, G0/G1 phase arrest, Cell longevity, Recombinant protein production == Introduction == Chinese hamster ovary (CHO) cells account for the largest number of approved host cells used in manufacturing of biopharmaceuticals between 1982 and 2014, and during the most recently examined period from 2010 to July 2014 (Walsh2014). Compared with other host cells such asEscherichia coliandSaccharomyces cerevisiae, CHO cells have an advantage in terms of post-translational modifications FD 12-9 of recombinant proteins. Recombinant protein productivity in CHO cells is highly associated with cell growth. Many attempts have been undertaken to control cell growth (Kumar et al.2007), such as cell engineering (Bi et al.2004; Fussenegger et al.1998; Strotbek et al.2013), cell cycle inhibitors (Du et al.2015), amino acid depletion (Fomina-Yadlin et al.2014) and temperature shift to reduce the temperature of the cell culture (Kaufmann et al.1999; Moore et al.1997; Trummer et al.2006). Several genes related to ribosome biogenesis and protein translation are highly expressed in the G1 phase of the cell cycle (Kumar et al.2007). Cell cycle arrest, particularly in the G1 phase, has been used to enhance productivity by Goat polyclonal to IgG (H+L)(Biotin) prolonging the production phase, in a number of commercially relevant cell lines such as hybridomas and CHO cells (Kumar et al.2007). Although regulation of the cell cycle improves production in CHO cells, many of the methods take time and effort, have variable process set points, or have other issues (Du et al.2015; Kumar et al.2007). In this study, we attempted to use a natural compound found in food, to improve the production capacity with a simple and uniform method. Oxidative stress causes several diseases (Ishizawa et al.2014; Tajima et al.2012; Yamano et al.2015). Catechin polyphenols found in green tea (Tsujimura1930,1934) have health benefits due to antioxidant activity (Higdon and Frei2003; Williamson and Manach2005). Among them, ()-epigallocatechin-3-gallate (EGCG) is the major catechin in green tea, and it has been suggested to be responsible for the majority of the potential health benefits attributed to green tea consumption (Nagle et al.2006). Several studies have reported that EGCG induced G0/G1 cell cycle arrest (Ahmad et al.2000a; Bae et al.2009; Gupta et al.2003; Ma et al.2014). EGCG has been reported to have great potential as a FD 12-9 cancer chemopreventive agent in clinical applications similarly to cell cycle modulators because of its safety, low cost and bioavailability (Singh et al.2002,2011). In normal cells, EGCG affects cell proliferation differently from carcinoma cells through different modulation of the FD 12-9 transcription factor, nuclear factor-B (NF-B) (Ahmad et al.2000b), or the activity of extracellular signal-regulated kinase (Erk) and protein kinase B (PKB)/Akt, and the expression of B cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) (Chung et al.2003). In non-cancer cells, EGCG FD 12-9 reversibly regulates the cell cycle-related genes, cyclin D1, cyclin E2, cyclin-dependent kinase 6 (Cdk6) and Cdk2 (Bae et al.2009). These cell cycle-related genes are suppressed when cells are in a medium containing EGCG, but restored to the original levels after its removal (Bae et al.2009). EGCG is not believed to have significant harmful effects on noncancerous animal cells. For example, EGCG increases neuronal survival in vivo and in vitro FD 12-9 (Ortiz-Lopez et al.2016; Singh et al.2016) and has anti-inflammatory properties in colitis models (Oz et al.2013). In addition, EGCG is a water-soluble molecule, which means.
However, under our conditions, EGCG addition was not effective when it was added at the intermediate point of culture, but it was effective when it was added on the first day of culture