Mucosal immunity and vaccine development

The mucosal system, which includes the respiratory, gastrointestinal, and urogenital tracts, serves as a primary entry point for pathogens, with a unique immune microenvironment and specialized defense mechanisms. In recent years, especially following the onset of the COVID-19 pandemic, there has been increasing recognition of the importance of mucosal immunity, motivated by an enhanced comprehension of its fundamental mechanisms. Currently, strategies based on mucosal delivery systems to administer antigens and induce strong mucosal protective immunity have become a key focus in the development of mucosal vaccines. Compared with conventional intramuscular delivery, mucosal vaccination can simultaneously elicit a robust local mucosal response, effectively block pathogen entry into the local mucosa, and generate systemic immune responses to prevent symptomatic infections and severe disease. In addition, mucosal delivery offers advantages such as ease of administration and low invasiveness, making it a more widely acceptable approach to vaccination. In the present study, we conducted a systematic review of the mechanisms of mucosal immunity, the technological platforms for mucosal vaccines, and proposed a perspective on the challenges and future directions for the development of next-generation mucosal vaccines, with the goal of enhancing public knowledge and awareness regarding mucosal immunity and its possible effects on global health.