EAPSI:Characterization of a Plant Cell-Produced Drug for the Treatment of Nerve Agent Exposure

Corbin Jasmine M, Davis CA

Investigators

Abstract

Plant cell suspension cultures are being investigated as a safe, cost-efficient, and scalable platform for the production of human therapeutic proteins. However, a major barrier for commercialization of this technology is the difference in the N©\glycosylation of proteins produced by humans and plants: the presence of plant-specific glycan structures can reduce the drug¡¯s efficacy and potentially cause an unwanted immune response. Thus, the goal of this work is to characterize the glycan profile of a protein therapeutic produced in a transgenic rice cell culture. This research will be conducted in collaboration with Dr. Kazuhito Fujiyama of Osaka University, an expert in analysis and modification of plant-made glycoproteins, and will enable use of his research group¡¯s highly specialized protocols, equipment, and expertise. The glycan profile will be determined for rice cell culture-produced butyrylcholinesterase, a native human enzyme used for the treatment of exposure to organophosphorus nerve agents such as sarin. The protein will be analyzed using liquid chromatography¨Cmass spectrometry, and the resulting data will be processed using bioinformatics software and databases of known plant-specific glycan structure. The glycans will be first cleaved from the protein and analyzed independently to determine glycan structure. Next, glycopeptide fragments will be generated and analyzed to provide information about site-specific glycosylation patterns. Knowledge of the glycan structures and site occupancy will later be used to further understanding of plant glycosylation patterns and to enable in vitro glycan humanization of the plant-made BuChE. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.