In:
International Archives of Allergy and Immunology, S. Karger AG, Vol. 118, No. 2-4 ( 1999), p. 190-192
Abstract:
〈 b 〉 Background: 〈 /b 〉 Antigen recognition by antibodies of different isotypes can result in completely different effects as exemplified by Type I allergy. While the IgE–antibody–mediated release of biological mediators constitutes the immunopathological basis for the immediate symptoms observed in allergic patients, allergen–specific IgG antibodies are thought to have protective effects. 〈 b 〉 Methods: 〈 /b 〉 Cell lines secreting five human monoclonal IgG antibodies (BAB1–BAB5) with specificity for the major birch pollen allergen Bet v 1 were established from a birch–pollen–allergic patient who had received birch– pollen–specific immunotherapy. The influence of the Bet v 1–specific IgG antibodies on IgE binding to Bet v 1 was investigated. BAB2 was expressed in 〈 i 〉 Escherichia coli 〈 /i 〉 as recombinant Fab, purified and tested for its ability to modulate Bet v 1–induced immediate–type skin reactions. 〈 b 〉 Results: 〈 /b 〉 The BAB antibodies belonged to different IgG subclasses (BAB1: IgG1; BAB2, BAB3, BAB5: IgG4; and BAB4: IgG2) reflecting a tendency towards Th2. BAB1 represented the only antibody which strongly blocked IgE binding to Bet v 1, whereas BAB 3–BAB5 had little effect on IgE binding. Surprisingly, natural BAB2 antibodies as well as recombinant BAB2 Fabs strongly enhanced IgE binding to Bet v 1 and Bet v 1–induced immediate–type skin reactions and thus represent ‘enhancing antibodies’. 〈 b 〉 Conclusion: 〈 /b 〉 The demonstration that anti–allergen IgG antibodies can also enhance IgE binding to a given allergen explains the unpredictability of specific immunotherapy as well as the controversy on the role of IgG in atopy.
Type of Medium:
Online Resource
ISSN:
1018-2438
,
1423-0097
Language:
English
Publisher:
S. Karger AG
Publication Date:
1999
detail.hit.zdb_id:
1482722-0
