ABSTRACT
This chapter discusses the molecules and pathways that control the development, activation, and effector functions of mast cell, eosinophil, and basophil populations in mucosal tissues. Mast cells, which are abundantly found in the skin and mucosal tissues, play an important role as regulators of multiple mucosal and mucosa-associated functions such as epithelial secretion, smooth muscle contraction, and local activation of nerves. Basophils arise from a common granulocyte-monocyte precursor in the bone marrow that has the capacity to differentiate into eosinophils, basophil–mast cell precursors, mast-cell precursors, and basophil precursors in vitro. In addition to the antibody-mediated immediate activation of basophils described earlier, basophils can be activated by IgE during certain types of chronic inflammation. Basophil development and effector functions can also be regulated by cytokines. In addition to antibody- and cytokine-mediated activation, basophils are activated by allergens, parasite antigens, and other pathogen-associated molecules. Basophils express toll-like receptors and complement receptors.
