title: Eosinophil infiltration into human skin is antigen-dependent in the late-phase reaction.
abstract: Eosinophils play a critical role in late-phase reaction allergic inflammatory responses, although the factors responsible for selective tissue eosinophilia are currently ill-defined. To determine whether recruitment of eosinophils is allergen-specific, or a feature of inflammation in allergic individuals, we have examined cutaneous cell infiltrates and endothelial cell adhesion molecule expression in atopic subjects 6 h (n = 8) and 24 h (n = 7) following ultraviolet-B (UVB) irradiation, or intradermal injection of late-phase reaction allergens or diluent control, using standard immunohistochemical techniques. The numbers of eosinophils were increased significantly, when compared to controls, at both 6 h (P < 0.01) and 24 h (P < 0.05), following intradermal allergen challenge, whereas no significant increase in eosinophils was observed following UVB irradiation. UVB and allergen both induced significant increases in neutrophils, monocytes and T cells at 24 h compared to control sites. An increased expression of endothelial cell adhesion molecules, E-selectin and intercellular adhesion molecule-1 (ICAM-1), was observed in both models of inflammation. Vascular cell adhesion molecule-1 (VCAM-1) was induced weakly on some biopsies following allergen, and not at all following UVB. These data indicate that eosinophil infiltration in susceptible individuals is a specific property of allergen. Although this study would support the postulated role of VCAM-1 in selective eosinophil recruitment, given its variable and weak expression, additional factors are likely to be involved.
authors.affiliation: Department of Allergy and Respiratory Medicine, UMDS, Guy's Hospital, London, U.K.
authors.forename: T M
authors.initials: TM
authors.lastname: Litchfield
authors.forename: C H
authors.initials: CH
authors.lastname: Smith
authors.forename: B A
authors.initials: BA
authors.lastname: Atkinson
authors.forename: P G
authors.initials: PG
authors.lastname: Norris
authors.forename: P
authors.initials: P
authors.lastname: Elliott
authors.forename: D O
authors.initials: DO
authors.lastname: Haskard
authors.forename: T H
authors.initials: TH
authors.lastname: Lee
mesh_terms: D000485:Allergens / Q000276:immunology*; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002465:Cell Movement; D017449:Dermatitis, Allergic Contact / Q000276:immunology*; D004804:Eosinophils / Q000276:immunology*; D004890:Erythema / Q000209:etiology / Q000276:immunology*; D006801:Humans; D009000:Monocytes / Q000276:immunology; D009504:Neutrophils / Q000276:immunology; D011832:Radiation Injuries / Q000276:immunology; D012867:Skin / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D014466:Ultraviolet Rays
chemical_list: D000485:Allergens; D015815:Cell Adhesion Molecules