Cellular and Molecular Basis of Immune Responsiveness at Mucosal Surface

Immunity at mucosal sites is typified by an apparent paradigm: active immunological suppression (tolerance) co-exists with a state of immune responsiveness and the two phenomena synergize with rather than antagonize each other to promote host defense.

The cellular and molecular mechanisms underlying this apparently paradoxical situation are being elucidated and appear to involve subpopulations of dendritic cells residing in or near the mucosal epithelial lining. Specific targeting of mucosal dendritic cells via appropriate transepithelial mobilization and activation should thus impact on the design of vaccines against mucosal infections and by and large of vaccines against inflammatory diseases such as allergies and autoimmune disorders.