title: Eosinophils in vasculitis: characteristics and roles in pathogenesis.
abstract: Eosinophils are multifunctional granular leukocytes that are implicated in the pathogenesis of a wide variety of disorders, including asthma, helminth infection, and rare hypereosinophilic syndromes. Although peripheral and tissue eosinophilia can be a feature of many types of small-vessel and medium-vessel vasculitis, the role of eosinophils has been best studied in eosinophilic granulomatosis with polyangiitis (EGPA), where eosinophils are a characteristic finding in all three clinical stages of the disorder. Whereas numerous studies have demonstrated an association between the presence of eosinophils and markers of eosinophil activation in the blood and tissues of patients with EGPA, the precise role of eosinophils in disease pathogenesis has been difficult to ascertain owing to the complexity of the disease process. In this regard, results of clinical trials using novel agents that specifically target eosinophils are providing the first direct evidence of a central role of eosinophils in EGPA. This Review focuses on the aspects of eosinophil biology most relevant to the pathogenesis of vasculitis and provides an update of current knowledge regarding the role of eosinophils in EGPA and other vasculitides.
authors.affiliation: Laboratory of Parasitic Diseases, National Institutes of Allergic and Infectious Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA.
authors.forename: Paneez
authors.initials: P
authors.lastname: Khoury
authors.affiliation: Vasculitis Translational Research Program, National Institutes of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Grayson
authors.affiliation: Laboratory of Parasitic Diseases, National Institutes of Allergic and Infectious Diseases, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA.
authors.forename: Amy D
authors.initials: AD
authors.lastname: Klion
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D018925:Chemokines / Q000276:immunology; D015267:Churg-Strauss Syndrome / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology / Q000276:immunology*; D002986:Clinical Trials as Topic; D016207:Cytokines / Q000276:immunology*; D004804:Eosinophils / Q000276:immunology*; D019317:Evidence-Based Medicine; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D007113:Immunity, Innate / Q000276:immunology; D016896:Treatment Outcome; D014657:Vasculitis / Q000276:immunology
chemical_list: D015415:Biomarkers; D018925:Chemokines; D016207:Cytokines; D005938:Glucocorticoids