title: Mast cells, their subtypes, and relation to asthma phenotypes.
abstract: Mast cells (MCs) are among the first cell types associated with allergies and asthma. Studies in human asthma have identified their presence in the lung submucosa and smooth muscle and also in the airway epithelium. As our understanding of the distribution and location of these MCs in the human airway has increased, it is clear that much remains to be understood regarding the presence and subtype of these MCs in relationship to asthma phenotypes, defined both clinically and on the basis of immunologic pathways. Human MCs have traditionally been divided into two major subtypes based on the protease granule content, with tryptase representing total MCs. There is emerging evidence that in the epithelium, MCs of an altered subtype (with tryptase, chymase, and/or carboxypeptidase A3) may play a role in the pathophysiology of poorly controlled, severe, Th2-associated asthma.
authors: 1 Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh Asthma Institute at UPMC/University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors: Merritt L
authors: ML
authors: Fajt
authors: Sally E
authors: SE
authors: Wenzel
mesh_terms: D001249:Asthma / Q000276:immunology*; D043422:Carboxypeptidases A; D053818:Chymases; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D006801:Humans; D008168:Lung / Q000166:cytology / Q000276:immunology*; D008407:Mast Cells / Q000166:cytology / Q000201:enzymology / Q000276:immunology*; D009130:Muscle, Smooth / Q000166:cytology; D010641:Phenotype; D020545:Respiratory Mucosa / Q000166:cytology; D012720:Severity of Illness Index; D018418:Th2 Cells / Q000276:immunology / Q000378:metabolism; D053802:Tryptases
chemical_list: D016207:Cytokines; C468648:CPA3 protein, human; D043422:Carboxypeptidases A; D053818:Chymases; D053802:Tryptases