Antiapoptosis Engineering for Improved Protein Production from CHO Cells.

Improving the time integral of viable cell concentration by overcoming cell death, namely apoptosis, is one of the most widely used strategies for the efficient production of therapeutic proteins. By establishing stable cell lines that overexpress antiapoptotic genes or downregulate proapoptotic genes, the final product yields can be enhanced as cells become more resistant to environmental stresses. From the selection of high-expressing clones to verification of antiapoptotic activity, the method to construct a stable antiapoptotic cell line is discussed in this chapter.

Six-Year Survival Outcomes for Patients with HER2-Positive Early Breast Cancer Treated with CT-P6 or Reference Trastuzumab: Observational Follow-Up Study of a Phase 3 Randomised Controlled Trial.

Background: The Phase 3 CT-P6 3.2 study demonstrated equivalent efficacy and comparable safety between CT-P6 and reference trastuzumab in patients with human epidermal growth factor receptor-2 (HER2)-positive early breast cancer after up to 3 years' follow-up.

Objective: To investigate long-term survival with CT-P6 and reference trastuzumab.

Untangling the mechanism of 3-methyladenine in enhancing the specific productivity: Transcriptome analysis of recombinant Chinese hamster ovary cells treated with 3-methyladenine.

3-Methyladenine (3-MA) is a chemical additive that enhances the specific productivity (q ) in recombinant Chinese hamster ovary (rCHO) cell lines. Different from its widely known function of inhibiting autophagy, 3-MA has instead shown to increase autophagic flux in various rCHO cell lines. Thus, the mechanism by which 3-MA enhances the q requires investigation.

Anti-Apoptosis Engineering for Improved Protein Production from CHO Cells.

Improving the time integral of viable cell concentration by overcoming cell death, namely apoptosis, is one of the widely used strategies for efficient production of therapeutic proteins. By establishing stable cell lines that overexpress anti-apoptotic genes or down-regulate pro-apoptotic genes, the final product yields can be enhanced as cells become more resistance to environmental stresses. From the selection of high-expressing clones to verification of anti-apoptotic activity, the method to construct a stable anti-apoptotic cell line is discussed in this chapter.

Chemical inhibition of autophagy: Examining its potential to increase the specific productivity of recombinant CHO cell lines.

Chinese hamster ovary (CHO) cells activate and undergo apoptosis and autophagy for various environmental stresses. Unlike apoptosis, studies on increasing the production of therapeutic proteins in CHO cells by targeting the autophagy pathway are limited. In order to identify the effects of chemical autophagy inhibitors on the specific productivity (qp ), nine chemical inhibitors that had been reported to target three different phases of autophagy (metformin, dorsomorphin, resveratrol, and SP600125 against initiation and nucleation; 3-MA, wortmannin, and LY294002 against elongation, and chloroquine and bafilomycin A1 against autophagosome fusion) were used to treat three recombinant CHO (rCHO) cell lines: the Fc-fusion protein-producing DG44 (DG44-Fc) and DUKX-B11 (DUKX-Fc) and antibody-producing DG44 (DG44-Ab) cell lines.

Effect of glucose feeding on the glycosylation quality of antibody produced by a human cell line, F2N78, in fed-batch culture.

The human cell line rF2N78 produces an antibody with a high galactosylation ratio which resembles human IgG. However, it has been observed that the aglycosylated antibody starts to appear when glucose is depleted. To determine whether glucose depletion is a main cause for aglycosylation of the antibody, fed-batch cultures of rF2N78 cells were performed using different feeding cocktails (glucose only, nutrient feeding cocktail without glucose, and nutrient feeding cocktail with glucose).

Autophagy and its implication in Chinese hamster ovary cell culture.

Chinese hamster ovary (CHO) cells, that are widely used for production of therapeutic proteins, are subjected to apoptosis and autophagy under the stresses induced by conditions such as nutrient deprivation, hyperosmolality and addition of sodium butyrate. To achieve a cost-effective level of production, it is important to extend the culture longevity. Until now, there have been numerous studies in which apoptosis of recombinant CHO (rCHO) cells was inhibited, resulting in enhanced production of therapeutic proteins.

Effect of culture pH on recombinant antibody production by a new human cell line, F2N78, grown in suspension at 33.0 °C and 37.0 °C.

The human host cell line, F2N78, is a new somatic hybrid cell line designed for therapeutic antibody production. To verify its potential as a human host cell line, recombinant F2N78 cells that produce antibody against rabies virus (rF2N78) were cultivated at different culture pH (6.8, 7.