Development and application of genomic tools for process enhancement in Chinese hamster ovary cells.

摘要

Chinese Hamster Ovary (CHO) cell lines have become the dominant host cell system for the production of recombinant proteins, therapeutics that have transformed the landscape of modern healthcare providing effective therapies for a wide variety of diseases from cancer to rheumatoid arthritis. Besides the capability to perform complex post translational modifications, their predominance stems from their ability for transformation from non-secretory cells to cells secreting at the levels of professional secretors in the human body. However, the genetic and physiological properties that render them such high producers are not well characterized. Genomic and proteomic tools can potentially aid in understanding and improving recombinant therapeutic production processes, leading to significant compression of the timeline for transition of the recombinant protein from lab to clinic. Through a collaborative effort with the Bioprocessing Technology Institute of Singapore (A*STAR), in this work, a near complete CHO transcriptome repertoire using high throughput sequencing technologies has been established. These EST sequences have been used to develop microarrays on both the Affymetrix and the Nimblegen platforms as well as proteomic tools, which have been applied for the profiling of CHO cells lines to better understand not only the process, but also the producing cells themselves. The promise of many molecular tools, including the ability to engineer CHO cells at the genome level, can only be realized to the fullest extent when the complete genome sequence, or atleast the genes and their regulatory sequences are available. This spurred the sequencing of the Chinese hamster genome, which, on completion yielded a 2.52 Gb genome, with approximately 27,000 annotated genes. As the field of cell culture bioprocessing matures, the physiological insight gained through the application of these genomic resources will serve as a direct route towards improving the producing cell, the process as well as the product.