Nathan Hotaling

Dendritic cells are the link between innate and adaptive immunity and are the most potent antigen presenting cells in the immune system. As such these cells represent an ideal target for modulating the immune response to implanted materials, combination products, and vaccine conjugates. Dendritic cells (DCs) have evolved to respond to a variety of pathogens via a vast array of membrane bound and intracellular receptors known as pattern recognition receptors or PRRs. These receptors recognize both endogenous and exogenous motifs and depending on which receptors are stimulated, and to what extent, modulate the ultimate DC phenotype. A particular class of PRRs known as C-type lectin receptors (CLRs) has recently been identified as a prevalent class of receptor on dendritic cells. C-type lectin receptors recognize characteristic pathogen and danger associated carbohydrate motifs. The functional outcome from the stimulation of these receptors, what the ideal surface presentation method of the glycan for these receptors is, and even the exact glycan structures many of these receptors will bind has yet to be elucidated. The goal of this proposal is to elucidate, from a large array of glycans, which carbohydrates, in what structures, and in which context modulate primary dendritic cell phenotype and can cause a functional immunomodulatory effect. The hypothesis is that glycans and glycoproteins when isolated and surface-immobilized have functional modulatory effects on primary human dendritic cell (DC) phenotype. It is also hypothesized that this modulatory affect can be controllably altered via the type, form, context, and/or density of carbohydrate presentation. This hypothesis will be validated by determining the molecular characteristics and contexts of glycan display that can functionally modulate DC phenotype. Once these characteristics have been determined a polymer carrier will then be developed to mimic these properties in a controllable and reproducible fashion. A high throughput (HTP) assay will then be developed that can determine functional cellular responses to surface immobilized glycans so that large arrays of glycans can be tested. Finally, exogenous, endogenous, and aberrant endogenous glycan arrays will be tested to determine the ability of the display methodology and HTP assay to select glycans of clinical significance.