Relevance of Ara h1, Ara h2 and Ara h3 in peanut‐allergic patients, as determined by immunoglobulin E Western blotting, basophil–histamine release and intracutaneous testing: Ara h2 is the most important peanut allergen

Clinical and Experimental Allergy - Tập 34 Số 4 - Trang 583-590 - 2004
Stef J. Koppelman1,2, Michel Wensing1, M. Ertmann1, André C. Knulst1, Edward F. Knol1
1Department of Dermatology/Allergology, University Hospital Utrecht, Utrecht, The Netherlands
2TNO Nutrition and Food Research, Zeist, The Netherlands

Tóm tắt

SummaryBackground A number of allergenic proteins in peanut has been described and the relative importance of these allergens is yet to be determined.Objectives We have investigated the relevance of previously identified peanut allergens in well‐characterized peanut‐allergic patients by in vitro, ex vivo and in vivo assays.Methods Thirty‐two adult peanut‐allergic patients were included based on careful and standardized patient history and the presence of peanut‐specific IgE. The diagnosis peanut allergy was confirmed using double‐blind placebo‐controlled food challenges in 23 patients. Major peanut allergens Ara h1, Ara h2 and Ara h3 were purified from peanuts using ion‐exchange chromatography. IgE immunoblotting was performed and IgE‐cross‐linking capacity was examined by measuring histamine release (HR) after incubating patient basophils as well as passively sensitized basophils with several dilutions of the allergens. Intracutaneous tests (ICTs) using 10‐fold dilution steps of the purified allergens and crude peanut extract were performed.Results Ara h2 was recognized most frequently (26 out of 32) in all tests and induced both positive skin tests and basophil degranulation at low concentrations, whereas Ara h1 and Ara h3 were recognized less frequently and reacted only at 100‐fold higher concentrations as analysed with HR and intracutaneous testing (ICT). Next to the three tested allergens, proteins with molecular weights of somewhat smaller than 15 kDa were identified as a IgE‐binding proteins on immunoblot in the majority of the patients (20 out of 32).Conclusion We conclude that Ara h2 is, for our patient group, the most important peanut allergen, and that previously unidentified peanut proteins with molecular weights of somewhat smaller than 15 kDa may be important allergens as well. ICT in combination with basophil–HR and IgE immunoblotting provides insight in the patient specificity towards the individual peanut allergens.

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Tài liệu tham khảo

Sampson HA, 1985, Food hypersensitivity and atopic dermatitis, evaluation of 113 patients, 669

Grundy J, 2002, Rising prevalence of allergy to peanut in children, data from 2 sequential cohorts, 110, 784

10.1016/S0091-6749(99)70224-1

Hourihane JO, 1997, An evaluation of the sensitivity of subjects with peanut allergy to very low doses of peanut protein, a randomized, double-blind, placebo-controlled food challenge study, 100, 596

10.1067/mai.2002.129235

10.1016/0091-6749(91)90325-I

10.1046/j.1365-2222.1998.00301.x

Becker WM., 1997, Characterization of Ara h1 by two‐dimensional electrophoresis immunoblot and recombinant techniques, new digestion experiments with peanuts imitating the gastrointestinal tract, 113, 118

10.1074/jbc.273.22.13753

10.1074/jbc.274.8.4770

10.1172/JCI118216

10.1111/j.1432-1033.1997.t01-1-00334.x

10.1016/0091-6749(92)90469-I

10.1159/000024203

10.1006/abbi.1997.9998

10.1016/S0091-6749(96)80014-5

10.1172/JCI5349

Koppelman SJ, 2003, Peanut allergen Ara h3, isolation from peanuts and biochemical characterization, 58, 1144

10.3109/02770906609106941

Dreborg S, 1993, Allergen standardisation of skin tests, Allergy, 48, 49, 10.1111/j.1398-9995.1993.tb04756.x

Laemmli UK., 1970, Cleavage of structural proteins during the assembly of the head of bacteriophage T4, Nature, 227, 359, 10.1038/227680a0

10.1073/pnas.76.9.4350

De Boer M, 1986, Metabolic comparison between basophils and other leukocytes from human blood, J Immunol, 136, 3447, 10.4049/jimmunol.136.9.3447

Pruzansky JJ, 1983, Dissociation of IgE from receptors on human basophils. I. Enhanced passive sensitization for histamine release, J Immunol, 131, 1949, 10.4049/jimmunol.131.4.1949

10.1016/S0091-6749(98)70178-2

10.1159/000231384

10.1002/eji.1830210404

10.1016/S0091-6749(97)70245-8

10.1046/j.1365-2222.1999.00521.x

10.1034/j.1398-9995.2001.056002132.x

10.4049/jimmunol.169.2.882

10.1016/S0091-6749(02)82053-X

10.1067/mai.2003.61

10.1111/j.1398-9995.1998.tb03967.x

Crowe SE, 1992, Gastrointestinal food hypersensitivity, basic mechanisms of pathophysiology, 103, 1075

10.1084/jem.182.6.1871

Knippels LMJ, 1999, Immune‐mediated effects upon oral challenge of ovalbumin‐sensitized Brown Norway rats, further characterization of a rat food allergy model, 156, 161