Adjuvants and delivery systems based on polymeric nanoparticles for mucosal vaccines

Most pathogens enter the body through mucosal surfaces. Therefore, vaccination through the mucosal route can greatly enhance the mucosal immune response. Vaccination via the mucosal surface is the most effective way to trigger a protective mucosal immune response, but the vast majority of vaccines used are administered by injection. Strategies to enhance the mucosal immunity have been developed by using vaccine adjuvants, delivery systems, bacterial or viral vectors, and DNA vaccines. Appropriate vaccine adjuvants and drug delivery systems can improve the immunogenicity of antigens, induce a stronger immune response, and reduce the vaccine dose and production cost. In recent years, many studies have focused on finding safe and effective vaccine adjuvants and drug delivery systems to formulate the mucosal vaccines for solving the above problems. Great progress has also been made in vaccine adjuvants and drug delivery systems based on biodegradable polymer nanoparticles. In this paper, the research progress of the mucosal vaccine and its related adjuvants and drug delivery systems in recent years was reviewed, and the application of polymers as adjuvants and drug delivery system in vaccine was prospected. This review provides a fundamental knowledge for the application of biodegradable polymer nanoparticles as adjuvants and carriers in mucosal vaccines and shows great application prospects.