Optimizing assembly of asymmetric peptide nanofiber vaccines for delivery through mucosal membranes

Mucosal vaccines are gaining increased attention due to their potential to tackle distinct bodily mucosae and induce immune responses to prevent and treat infectious diseases and autoimmune conditions such as inflammatory bowel disease (IBD). Some benefits over traditional vaccination methods include needle-free delivery and localized action through the production of IgA and tissue resident T cells. Firstly, materials need to cross a dense layer of mucus before reaching the epithelium and achieving the desired therapeutic goal. Moreover, each mucosal membrane is distinct and presents its own properties, for instance, pH, immune cell type, turnover rate, etc, that call for specific biomaterial properties for successful delivery. Inspired by infectious organisms that naturally cross human mucus to impair cellular function (e.g., Influenza A virus), this project aims to develop a safe and effective carrier platform that can both attach to and cross mucosae in time before being carried away by natural mucus turnover in the host organism. The asymmetry of the fibers is essential so that they can perform a Brownian ratchet-like motion, where one subunit of the fiber is constantly cleaving mucus whereas the other provides support by attaching to mucus. After conjugating each subunit with a fluorophore, we observed through confocal microscopy that they combine most effectively at 95°C for 10 minutes. We also tested the binding activity of two mucin-binding peptides identified from the literature as well as epitopes of interest through a mucoadhesion assay. C3a1 showed the highest binding activity. Knowing this, we aim to conjugate this binding subunit with a mucus cleaving enzyme and assess their overall dynamics in mucus.