Title: Polymeric Biomaterials for Gene and Vaccine Delivery
Speaker: Associate Professor Wang Chun（University of Minnesota, USA）
Time: 9:30-11:30a.m., Jan.8th, 2016
Venue: Room 214, Building No. 16, Wushan Campus

Abstract:
Since the last decade, much progress has been made toward designing cationic polymeric gene carriers with high transfection efficiency and low cytotoxicity and in elucidating the relationship between polymer structure and gene delivery performance. However, delivery of gene-based vaccine to improve antigen presentation and immune activation poses unique challenges that have yet been fully addressed. We have shown that a chemically simple cationic polymer can have surprisingly high efficiency in transfecting dendritic cells (DCs), leading to antigen-presentation and T cell activation, but the mechanism behind in vitro and in vivo delivery is rather complex. Further, cellular stress responses (including apoptosis and autophagy) provoked by polyplexes and the timing of phenotypic maturation of DCs may be manipulated to improve transgene expression and cross-presentation of antigen. In addition to serving as models, such polymers may have the potential to be practically useful carriers of DNA vaccine in preventing and treating diseases. To facilitate formulation and delivery of multi-component cancer vaccines, we have recently developed a new class of biodegradable semi-solid polymers (named Caproxamers®) that allows easy loading and controlled release of both hydrophobic and hydrophilic cargos. Subcutaneous injection of antigens and adjuvants formulated in an ortho-ester-containing Caproxamer induced antigen-specific antibody and T cell responses and showed therapeutic benefit in mice with orthotopic brain tumor. Combining simplicity in synthesis with versatility in properties, the potential use of the Caproxamers may go beyond vaccine delivery to include other drug delivery applications.