Grant: CIHR Fellowship

The aim of this project is to engineer proteins to bind to glycans. Glycans, or carbohydrates, saccharides, or simply sugars, are indispensable for life on earth. Glycans are the most abundant organic molecules on the planet, and every known cell type wears a patterned coat. Indeed, glycan patterns are linked to a wide range of diseases, including infection, inflammation, and cancer. Although the exceptional potential of glycans for innovative disease detection and prevention has been recognized for some time, their potential has barely been tapped because of critical technical challenges. Proteins capable of binding glycans could detect altered glycosylation and be used to predict, diagnose, and prevent disease, and have potentially profound therapeutic impact. Natural glycan-binding proteins, such as lectins, have limited use in studying glycans due to low specificity and affinity. Hence, there is a need to build new tools to probe glycans and their functions. Nanobodies (Nb) are uniquely suited to overcome these critical bottlenecks and complex technical challenges. The rationale is that Nb are small tractable single-domain antibodies that can be evolved to bind virtually any epitope. For this project, I shall leverage my expertise in the different disciplines of directed evolution, structural biology, and protein engineering, to engineer Nbs that bind glycans with high affinity and specificity, using mucus as a natural glycan source. The Ribbeck lab has shown mucus glycans are key components of the innate immune system that promote beneficial microbes, while limiting pathogens. I have developed a mucus glycan array, with >200 mucus glycans, to screen for Nb binding. This unique glycan array will allow for the engineering of glycan-binding Nbs to identify and potentially suppress, disease states. This proposal sets a firm experimental groundwork that could lead to pivotal changes in the prevention and treatment of diseases related to impaired glycan structures.