Strategies for mucosal vaccine development.

Vaccines able to induce both secretory IgA for protection of mucosal surfaces and systemic immunity to pathogens invading the host are of great interest in the war against infectious diseases. Mucosal vaccines trigger immune cells in mucosal inductive sites and thus can induce immunity in both the mucosal and systemic compartments. This review presents a critical survey of adjuvants and delivery systems currently being tested for mucosal immunization. A better understanding of cellular and molecular factors involved in the regulation of mucosal immunity will help in the design of safer mucosal vaccines to elicit the appropriate protective immune response to a given pathogen.