N-Glycosylation has been shown to be a major factor in the overall efficacy of a therapeutic protein. However, the current inability to produce proteins with specific homogeneous N-glycan structures precludes the elucidation of structure-function relationships. Glycoproteins make up the vast majority of therapeutic proteins entering the market place. One of the fundamental challenges of glycobiology and the biopharmaceutical industry in particular is the ability to design and produce individual glycoforms of a therapeutic protein that impart maximum efficacy. GlycoFi's yeast based protein expression platform enables the manufacturing of therapeutic proteins with specific predetermined human N-glycosylation structures. In the future these glycoengineering efforts will make it possible to screen for and select the specific N-glycosylation structures that impart the highest possible efficacy to glycoprotein-based drugs. This proposal seeks to understand how these uniform N-glycan structures can be utilized to influence tissue distribution and pharmacokinetics of a glycoprotein. This knowledge will ultimately lead to the development of targeted drugs with increased potency and reduced toxicity. In Phase I of this project, different homogeneous glycoforms of the model protein Kringle3, chosen for its lack of biological function, will be produced, radiolabeled and injected into rats for analysis of N-glycosylation dependent blood clearance and tissue localization. The data obtained from Phase I will be applied in Phase II for the analysis of complex proteins of therapeutic value. Relevance to Public Health: GlycoFi's yeast-based protein production technology enables the study of N-glycosylation structure-function relationships and creates the ability not only to pinpoint the specific glycoforms that optimize the bioactivity, pharmacokinetics and overall efficacy of a therapeutic protein, but also to manufacture them at low cost with a high degree of uniformity. GlycoFi's technology will provide the biopharmaceutical industry with a high capacity alternative to mammalian cell culture that will allow life-improving drugs to reach the clinic in a faster, more cost-effective manner.
