Genetic engineering has allowed the production of subunit vaccines in a whole range of systems, each with their own advantages and disadvantages.
However most subunit vaccines do not generate a mucosal immune response.
In our approach, we are investigating a wide combinatorial range of antigen-antibody fusion molecules that can effectively cross the gut barrier and lead to mucosal immunity. The gut barrier is a selectively permeable membrane, were transcytosed antigens can either induce an immune reaction or a tolerogenic reaction. Among parameters, specific targeting to immune cells is important for mucosal immune response.
In a project together with Dr. Cox (Immunology Lab, UGent) and Dr. Sanders (Lab of Genetherapy, UGent), different recombinant mucosal vaccines will be produced in plants. The Cox lab recently identified a receptor for protein transcytosis on the enterocytes of the small intestine. Antibodies against these receptors were transcytosed across the small intestine gut lining and resulted in elicitation of specific immune response. We will produce fusions between a monoclonal antibody against this receptor and different antigens in plant expression platforms, starting with the green fluorescent reporter as model antigen. Fusion vaccine with antibodies targeting an enterocyte receptor will allow evaluating transcytosis across the enterocytes and interaction with immune cells in vitro. In a second phase, delivery of the recombinant vaccines within the feed will allow to study the in vivo systemic and mucosal immune responses.