title: Allergic and nonallergic asthmatics have distinct patterns of T-cell activation and cytokine production in peripheral blood and bronchoalveolar lavage.
abstract: Activation of lymphocyte subpopulations was determined in conjunction with levels of cytokines in peripheral blood and bronchoalveolar lavage (BAL) of asthmatics. Allergic asthmatics had increased numbers of CD4+ IL-2R+ T cells in peripheral blood and BAL, and T-cell activation closely correlated with numbers of low-affinity IgE receptor (CD23) bearing B cells. In contrast, in nonallergic asthmatics both CD4+ and CD8+ T cells from blood and BAL had increased expression of IL-2R, HLA-DR, and VLA-1. Furthermore, in the nonallergic asthmatics CD8+ T cells were decreased in blood but increased in BAL. Cytokine levels were determined in BAL fluid and supernatants from purified peripheral blood T cells and enriched BAL lymphocyte preparations. Allergic asthmatics were characterized by increased levels of IL-4 and IL-5, and this elevated IL-4 contributed to the elevated IgE levels found in these allergic subjects. In contrast, nonallergic asthmatics had elevated levels of IL-2 and IL-5, with IL-2 contributing to T-cell activation. In both types of asthma, the close correlation of IL-5 levels with eosinophilia suggests that IL-5 is responsible for the characteristic eosinophilia of asthma. Thus, we provide evidence of distinct T-cell activation resulting in different spectra of cytokines in allergic and nonallergic asthma.
authors.affiliation: Swiss Institute of Allergy and Asthma Research, Davos, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Walker
authors.forename: E
authors.initials: E
authors.lastname: Bode
authors.forename: L
authors.initials: L
authors.lastname: Boer
authors.forename: T T
authors.initials: TT
authors.lastname: Hansel
authors.forename: K
authors.initials: K
authors.lastname: Blaser
authors.forename: J C
authors.initials: JC
authors.lastname: Virchow
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000209:etiology / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000276:immunology*; D016207:Cytokines / Q000032:analysis / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000150:complications* / Q000276:immunology; D007371:Interferon-gamma / Q000032:analysis; D007378:Interleukins / Q000032:analysis; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets; D008297:Male; D008875:Middle Aged; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D016207:Cytokines; D007378:Interleukins; D007371:Interferon-gamma