UNS:Intergrating novel nutrient feeding strategies with computational glycosylation models to improve production of complex biotherapeutics from mammalian factories

Johns Hopkins University, Baltimore MD

Investigators

Abstract

1512265 Betenbaugh, Michael J. Biopharmaceuticals such as recombinant erythropoietin (rEPO) have transformed the lives of millions of patients in the US and around the world by enabling the recipients to address chronic renal failure or other illnesses. Unfortunately, the costs of providing these drugs are often prohibitive, limiting the availability and affordability of biotherapeutic treatments for patients that need them. This project will address both cost and efficacy challenges by transforming biomanufacturing with novel media additives. The quality of rEPO and other drugs will be enhanced by altering the properties of biopharmaceuticals in ways that endow these products with longer circulatory lifetimes, allowing patients to take lower doses at longer intervals. Likewise, this project will lower the costs of manufacturing by incorporating novel inexpensive nutrients that improve the capacity of producer cells to generate high quality drugs. In tandem, advanced computational models will be implemented in order to determine the optimal media formulations for generating high quality biopharmaceuticals. In addition, students from the high school to the post-graduate level will be educated and engaged in important bioprocessing techniques including mammalian cell culture, media design, and pharmaceutical manufacturing. In order to achieve these goals, an experimental and computational systems biotechnology approach will be implemented in which the media will be designed to optimize the glycosylation profile of biotherapeutics such as recombinant erythropoietin (rEPO) produced in Chinese hamster ovary (CHO) cells. CHO cells have emerged as a major cell factory for generating glycoprotein biotherapeutics. The structure and nature of the oligosaccharide (or glycan) component of a glycoprotein therapeutic is extremely important to the quality, efficacy, and value of the products. Biosynthetically, glycan structure is dictated by two factors: levels of glycosylation enyzmes and availability of nucleotide sugar substrates. This project will integrate experimental and computational methods to manipulate nutrient components to enhance the levels of these critical nucleotide sugar substrates and improve glycosylation. A series of novel sugar analogs will be investigated for their capacity to increase the nucleotide sugar pool and improve quality of rEPO and other biological products. These novel sugar analogs, which are simple and inexpensive to produce, contain chemical modifications on specific carbon groups that facilitate crossing the cell membrane for efficient channeling into pathways for nucleotide sugar synthesis. In order to elucidate the impact of these and other nutrients, these media components will be incorporated into a computational model of N-linked glycosylation that currently is based only on glycosylation enzyme transferase activity. The model will be extended to predict the influence on final glycan structures of nucleotide sugar biosynthesis from nutrients or supplements in the media. Such an expansion of the current glycoinformatics suite will enable users to design optimal media compositions for a desirable N-glycan profile present on glycoprotein biotherapeutics. By including the effect of nutrients on metabolism and linking that to the final glycan structure, this modeling tool will have significant versatility and power for rapidly and cost-effectively improving biotherapeutic product quality. As a result, novel nutrients will be incorporated into the bioprocessing media formulation of mammalian cell cultures with the assistance of comptutational algorithms in order to increase production and yield of desirable complex high quality biotherapeutics and reduce the need for time consuming and expensive experimental investigation. This approach may have a broad impact across a number of bioprocesses and biological products. This award by the Biotechnology and Biochemical Engineering Program of CBET is co-funded by the Biomaterials Program of the Division of Materials Research.