ABSTRACT

For several decades mast cells and basophils have been recognized as important e¡ector cells in the pathogenesis of asthma. Elevated numbers of airway mast cells (1) and their activation products have been clearly documented in the airways of asthmatic patients. Likewise, the accumulation of basophils in the lungs of patients with fatal asthma (2) and in the late-phase airway responses of experimental allergen challenge (3^5) has linked this cell type and itsmediators to the process of airway in£ammation. In this chapter we will review the functions of both of these leukocytes, with an emphasis on their contribution to asthma pathogenesis. Given the complexity of the airway in£ammatory response in asthma and the involvement of several immunological pathways and cell types, our discussion of cell-speci¢c functions in vivo will rely on evidence from human studies as well as established animal and in vitro models.