Small molecule epigenetic modulators for enhancing recombinant antibody production in CHO cell cultures

Abstract

Small molecule epigenetic modulators that modify epigenetic states in cells are useful tools for regulating gene expression by inducing chromatin remodeling. To identify small molecule epigenetic modulators that enhance recombinant protein expression in Chinese hamster ovary (CHO) cells, we examined eight histone deacetylase inhibitors (iHDACs) and six DNA methyltransferase inhibitors as chemical additives in recombinant CHO (rCHO) cell cultures. Among these, a benzamidebased iHDAC, CI994, was the most effective in increasing monoclonal antibody (mAb) production. Despite suppressing cell growth, the addition of CI994 to mAbexpressing GSR cell cultures at 10 μM resulted in a 2.3-fold increase in maximum mAb concentration due to a 3.0-fold increase in specific mAb productivity (q mAb ).CI994 increased mAb messenger RNA levels and histone H3 acetylation in GSR cells, and chromatin immunoprecipitation-quantitative polymerase chain reaction analysis revealed that CI994 significantly increased the histone H3 acetylation level at the cytomegalovirus promoter driving mAb gene expression, indicating that chromatin remodeling in the promoter region results in enhanced mAb gene transcription and q mAb . Similar beneficial effects of CI994 on mAb production were observed in mAbexpressing CS13-1.00 cells. Collectively, our findings indicate that CI994 increases mAb production in rCHO cell cultures by chromatin remodeling resulting from acetylation of histones in the mAb gene promoter.

Genome-Wide CRISPR/Cas9 Screening Unveils a Novel Target ATF7IP–SETDB1 Complex for Enhancing Difficult-to-Express Protein Production

“…Epigenetic modifications, such as histone modification and DNA methylation, have been successfully used to achieve specific phenotypes in CHO cells . Numerous studies have demonstrated that the inhibition of histone deacetylases and DNA methyltransferases leads to enhanced cell-specific productivity with growth suppression, − but to our knowledge, the modulation of histone methyltransferases has not yet been explored in CHO cells. In our study, we observed that inhibiting the histone methyltransferase ATF7IP–SETDB1 complex improved cell-specific productivity and suppressed cell growth.…”

Genome‐wide CRISPR/Cas9 knockout screening to mitigate cell growth inhibition induced by histone deacetylase inhibitors in recombinant CHO cells

“…Here, when iHDACs were added to CHO-BS cell cultures, q p was increased up to three-fold, but the bsAb concentration was increased by <10% owing to reduced VCC (Figure 1). Because the degree of growth concentration, CHO-BS cells showed more severe growth inhibition than GSR cells (Kim et al, 2022). When using iHDACs-resistant rCHO cells, recombinant protein production can be further enhanced by mitigating the growth-inhibitory effects of iHDACs.…”

“…Because the degree of growth inhibition by iHDACs varies among rCHO cell lines, iHDAC concentrations must be optimized for individual rCHO cell lines. At the same CI994 concentration, CHO‐BS cells showed more severe growth inhibition than GSR cells (Kim et al, 2022). When using iHDACs‐resistant rCHO cells, recombinant protein production can be further enhanced by mitigating the growth‐inhibitory effects of iHDACs.…”

“…Histone deacetylase inhibitors (iHDACs) such as sodium butyrate (NaBu), valeric acid, and CI994, act as chemical additives to enhance recombinant protein production in rCHO cell cultures (Backliwal et al, 2008; Kim et al, 2022; Palermo et al, 1991). iHDACs increase specific productivity while inhibiting the cell growth of rCHO cells in a dose‐dependent manner (Birzele et al, 2010; Kim & Lee, 2000; Seong Lee & Lee, 2012).…”

Strategies and Considerations for Improving Recombinant Antibody Production and Quality in Chinese Hamster Ovary Cells

“…The production of recombinant antibody drugs is mostly achieved by constructing expression vectors in vitro through genetic engineering technology. Given that recombinant antibodies often need to undergo a series of post-translational modifications (such as glycosylation modification), folding, and correct cleavage, antibody drugs with biological activity and low immunogenicity can be produced, therefore, mammalian cells have become the dominant system for the production of recombinant antibodies, especially for full-length monoclonal antibodies ( Hussain et al, 2021 ; Kim et al, 2021 ; Ha et al, 2022 ).…”