Autophagy and its implication in Chinese hamster ovary cell culture

Abstract

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. Recently, autophagy in rCHO cells has drawn attention because it can be genetically and chemically controlled to increase cell survival and productivity. Autophagy is a global catabolic process which involves multiple pathways and genes that regulate the lysosomal degradation of intracellular components. A simultaneous targeting of anti-apoptosis and pro-autophagy could lead to more efficient protection of cells from stressful culture conditions. In this regard, it is worthwhile to have a detailed understanding of the autophagic pathway, in order to select appropriate genes and chemical targets to manage autophagy in rCHO cells, and thus to enhance the production of therapeutic proteins.

Meta‐Analysis of Publicly Available Chinese Hamster Ovary (CHO) Cell Transcriptomic Datasets for Identifying Engineering Targets to Enhance Recombinant Protein Yields

“…Both the regulatory profiles of the PG and GG point toward a clear pattern of downregulation of lysosomal activity by disrupting trafficking and recycling of lysosomal proteins and structural lipids and impairing lysosomal processing. None of these proteins have been engineered in recombinant CHO cells, however strategies to induce autophagocytic and suppress lysosomal pathways have been implemented before using inhibitors as described in Kim et al with up to 30% increase in recombinant mAB yields …”

High insulin impaired ovarian function in early pregnant mice and the role of autophagy in this process

“…ment, and protein homeostasis. Autophagy is reported to contribute to the maintenance of ovarian functioning in many ways [23][24][25]. Insulin is reported to be involved in the regulation of autophagy, and studies have shown that insulin can inhibit autophagy through activating mTORC1 (mechanistic target of rapamycin complex 1) and PKB (protein kinase B) [26].…”

Glutamine substitution: the role it can play to enhance therapeutic protein production

“…Autophagy, which is known as a programed cell death type 2, plays an important role in the maintenance of intracellular homeostasis via regulation of the cellular response to a variable metabolic stress [43,44]. As shown in Figure 3, addition of 10 mM ammonia to the cultures induced conversion of LC3-1 to LC3-2 form, which is an autophagy marker.…”