A compendium of stable hotspots in the CHO genome
Date
2023-04-04
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Biotechnology and Bioengineering
Abstract
The use of targeted integration for industrial CHO cell line development currently requires significant upfront effort to identify genomic loci capable of supporting multigram per liter therapeutic protein production from a limited number of transgene copies. To address this barrier to widespread adoption, we characterized transgene expression from thousands of stable hotspots in the CHO genome using the Thousands of Reporters Integrated in Parallel high-throughput screening method. This genome-scale data set was used to define a limited set of epigenetic properties of hotspot regions with sizes on the order of 10 kb. Cell lines with landing pad integrations at eight retargeted hotspot candidates consistently exhibited higher transgene mRNA expression than a commercially viable hotspot in equivalent culture conditions. Initial benchmarking of NISTmAb and trastuzumab productivity from one of these hotspots yielded mAb productivities of approximately 0.7–2 g/L (qP range: 2.9–8.2 pg/cell/day) in small-scale fed-batches. These findings indicate the list of hotspot candidates identified here will be a valuable resource for targeted integration platform development within the CHO community.
Description
This article was originally published in Biotechnology and Bioengineering. The version of record is available at: https://doi.org/10.1002/bit.28390. © 2023 The Authors. Biotechnology and Bioengineering published by Wiley Periodicals LLC.
Keywords
bioprocessing, CHO cell, genomic hotspot, site-specific integration, TRIP
Citation
Hilliard, W., & Lee, K. H. (2023). A compendium of stable hotspots in the CHO genome. Biotechnology and Bioengineering, 1– 11. https://doi.org/10.1002/bit.28390