Generation and Maintenance of Mucosal Memory B Cell Responses?

The mucosal immune system comprises B cells that can mount potent antibody responses against a variety of mucosal pathogens. Mucosal B cell responses can play a decisive role in protection against mucosal pathogens. Induction of mucosal B cell responses can be achieved through mucosal vaccination. However, mucosal administration of antigens without the use of adjuvants or delivery systems can lead to tolerance rather than immunity, and thus considerable efforts have been focused on development of effective immunopotentiating adjuvants and delivery systems. However, because the ultimate goal of vaccination is the induction and maintenance of immunological memory, the underlying mechanisms for induction of long-term mucosal B cell memory need to be analyzed for the selection of appropriate adjuvants. Moreover, as the antigen unspecific innate immune system invoked by adjuvants contributes significantly to the development of antigen-specific B cell responses, and presumably B cell memory, optimal interaction of B cells with cellular components of the innate immune system is required. To better understand the mechanisms that lead to the induction of mucosal antibody responses, antibodies against single epitopes from specific B cell clones as opposed to antibodies against large poly proteins from multiple B cell clones can be studied. This review deals with the concept of mucosal B cell memory with special emphasis on efforts to devise effective prophylactic or therapeutic vaccines.