title: Stimulation of IgE and IgA production by CD45RA T helper cells in atopic patients.
abstract: The role of CD45RA T cells on allergen-dependent lymphocyte functions was analyzed in atopic patients. As compared with age-matched nonatopic controls, atopic patients exhibited a significantly (p < 0.01) increased frequency of CD45RA T cells in peripheral blood. Concentration of serum IgE correlated with increases in this T cell subset. In contrast to nonatopic controls, not only CD45RO but also CD45RA T cells from atopic patients provide help for allergen-stimulated IgE and IgA production, and they act in a synergistic fashion. Transwell coculture experiments revealed that optimal production of IgE and IgA required physical contact of CD45RA T cells with B cells. Freshly prepared and in vitro-activated CD45RO and CD45RA T cells from atopic patients showed an increased expression of CD40 ligand when compared with nonatopic individuals. In addition, CD45RA (and CD45RO) T cells from atopic individuals produced IL-4, IL-5, and IFN-gamma when stimulated with mitogens. Whereas stimulation of normal lymphocytes with tetanus Ag was followed by conversion of the CD45RA to the CD45RO phenotype, T cells from atopic donors did not acquire the CD45RO isoform to the same degree despite T cell activation. In atopic patients, addition of IL-4 to anti-CD3/anti-TCR stimulated CD45RA T cell prevented the shift towards the CD45RO phenotype. These data indicate that a subset of CD45RA T cells plays a unique role as effector T cells regulating IgE and IgA production in atopic patients.
authors.affiliation: Department of Pediatric Pneumology and Immunology, Virchow Clinic, Humboldt University, Berlin, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Nasert
authors.forename: N
authors.initials: N
authors.lastname: Burtchen
authors.forename: F
authors.initials: F
authors.lastname: Kussebi
authors.forename: M
authors.initials: M
authors.lastname: Millner
authors.forename: R
authors.initials: R
authors.lastname: Kroczek
authors.forename: T
authors.initials: T
authors.lastname: Jung
authors.forename: R
authors.initials: R
authors.lastname: Schwinzer
authors.forename: U
authors.initials: U
authors.lastname: Wahn
authors.forename: H
authors.initials: H
authors.lastname: Renz
mesh_terms: D000485:Allergens / Q000494:pharmacology; D001402:B-Lymphocytes / Q000276:immunology; D002450:Cell Communication / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000276:immunology*; D007070:Immunoglobulin A / Q000096:biosynthesis* / Q000097:blood; D007073:Immunoglobulin E / Q000096:biosynthesis* / Q000097:blood; D016130:Immunophenotyping; D017493:Leukocyte Common Antigens / Q000032:analysis*; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D018655:Lymphocyte Count; D006377:T-Lymphocytes, Helper-Inducer / Q000145:classification / Q000276:immunology / Q000378:metabolism*
chemical_list: D000485:Allergens; D016207:Cytokines; D007070:Immunoglobulin A; D007073:Immunoglobulin E; D017493:Leukocyte Common Antigens