Abstract | BACKGROUND:
IgE-dependent activation of mast cells and basophils through the high-affinity IgE receptor ( Fc epsilon RI) is involved in the pathogenesis of allergen-induced immediate and late responses. OBJECTIVE: We investigated the expression and cellular distribution of Fc epsilon RI in the nasal mucosa after allergen challenge in patients with summer hay fever. METHODS: Fourteen grass pollen-sensitive patients and seven normal control subjects underwent nasal challenge with grass pollen and allergen diluent in random order separated by 2 weeks. Nasal airway caliber was monitored by acoustic rhinometry, and nasal biopsy was performed at 6 hours. Messenger RNA for Fc epsilon RI was determined by using reverse-transcription polymerase chain reaction, and Fc epsilon RI protein expression was determined by immunohistology with a mouse monoclonal antibody (22E7) and a rabbit polyclonal antibody (997) directed against the alpha subunit. Co-localization of Fc epsilon RI receptors was performed by using double-immunostaining methods. RESULTS: In atopic subjects, there was a significant early decrease in nasal airway caliber, which extended up to 6 hours after allergen challenge. Fc epsilon RI mRNA levels were elevated at 6 hours (p = 0.03). Cells expressing Fc epsilon RI protein were increased in patients with atopic rhinitis compared with normal control subjects (p = 0.03). Further increases in Fc epsilon RI+ cells were observed after allergen challenge only in the atopic group (p = 0.02). Double immunohistochemistry revealed that the majority of Fc epsilon RI+ cells were mast cells (64%), followed by macrophages (20%), eosinophils (4%), and dendritic cells (2%), with 10% Fc epsilon RI+ cells being unidentified. CONCLUSIONS:
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Authors | K Rajakulasingam, S R Durham, F O'Brien, M Humbert, L T Barata, L Reece, A B Kay, J A Grant |
Journal | The Journal of allergy and clinical immunology
(J Allergy Clin Immunol)
Vol. 100
Issue 1
Pg. 78-86
(Jul 1997)
ISSN: 0091-6749 [Print] United States |
PMID | 9257791
(Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial)
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Chemical References |
- Allergens
- RNA, Messenger
- Receptors, IgE
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Topics |
- Adult
- Allergens
(pharmacology)
- Antibody Affinity
- Cell Movement
(immunology)
- Dendritic Cells
(metabolism)
- Eosinophils
(metabolism)
- Female
- Humans
- Immunohistochemistry
- Macrophages
(metabolism)
- Male
- Mast Cells
(metabolism)
- RNA, Messenger
(biosynthesis)
- Receptors, IgE
(biosynthesis, genetics)
- Rhinitis, Allergic, Seasonal
(etiology, immunology, metabolism)
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