ABSTRACT

Mucosal epithelia separate the external environment from the tissues of the body. This chapter describes B cells and antibodies associated with the mucosal immunity and the progression of mucosal B-cell development from the inductive phase in organized follicles in gut-associated lymphoid tissue to the production of immunoglobulins by plasma cells in effector mucosal tissues. Mucosal tissue can be subdivided into structures and cells associated with the inductive or the effector arms of the mucosal immune response. Peripheral lymphoid tissue develops in a largely antigen-free environment, whereas mucosal lymphoid tissues are exposed to the lumenal microbiota or their components from the earliest moments after birth and face constant antigenic stimulation throughout life. In the small intestine, the induction and regulation of the mucosal B-cell response occurs primarily in Peyer's patches, the clusters of organized lymphoid tissue concentrated in the terminal ileum in most mammalian species.