title: Fel d 1-specific IgG antibodies induced by natural exposure have blocking activity in skin tests.
abstract: Cat-allergic patients frequently have IgG antibodies directed against Fel d 1. The aim of this study was to investigate whether these IgG antibodies influence the results of the skin test. Titrated skin tests were performed with Fel d 1 and IgE and IgG antibody levels were measured in 59 patients with cat allergy. Levels of specific IgG against Fel d 1 ranged from less than 0.25 to 3.5 microgram/ml. By means of a multiple regression analysis it was shown that the amount of specific IgG antibodies contributes significantly to the results of the skin test. Presence of specific IgG against Fel d 1 was accompanied by higher skin thresholds for Fel d 1. In conclusion, this study indicates that even low levels of specific IgG, induced by natural exposure to cat allergens, have a blocking effect on the early phase skin reaction.
authors.affiliation: Department of Pulmonology, Academic Medical Center, University of Amsterdam, The Netherlands.
authors.forename: A M
authors.initials: AM
authors.lastname: Witteman
authors.forename: S O
authors.initials: SO
authors.lastname: Stapel
authors.forename: D H
authors.initials: DH
authors.lastname: Sjamsoedin
authors.forename: H M
authors.initials: HM
authors.lastname: Jansen
authors.forename: R C
authors.initials: RC
authors.lastname: Aalberse
authors.forename: J S
authors.initials: JS
authors.lastname: van der Zee
mesh_terms: D000293:Adolescent; D000328:Adult; D000485:Allergens; D000818:Animals; D019138:Antibodies, Blocking / Q000097:blood*; D000918:Antibody Specificity; D002415:Cats / Q000276:immunology*; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007073:Immunoglobulin E / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood*; D007428:Intradermal Tests; D008297:Male; D008875:Middle Aged
chemical_list: D000485:Allergens; D019138:Antibodies, Blocking; D006023:Glycoproteins; D007074:Immunoglobulin G; D007073:Immunoglobulin E; C059296:Fel d 1 protein, Felis domesticus