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Dictionary of Allergies .. Hemoglobin of Chironomids

Hemoglobin of Chironomids

Chironomids, of which approximately 10,000 species exist, are reported to cause severe immediate type allergic diseases in man. Hemoglobins of chironomids are potent inhalative allergens in humans. Well characterized allergens are the hemoglobins of Chironomus thummi (Chi t I) for which IgE-binding fragments have been identified.

The allergy is common in water rich areas and among fish hobbyists[1]. The specific immune response to Chi t I is associated with the HLA-D region. Baur X. (1980)investigated by radioimmunologic methods for antibody estimation, skin tests, and complementary clinical examinations 99 persons handling larvae of chironomids or their extracts. Approximately 1/3 of the exposed subjects suffered from respiratory hypersensitivity caused by IgE antibodies specific to hemoglobin molecules of this insect species. It has been successful to locate the antigenic determinant of one of these hemoglobins within a defined amino acid sequence.

These represents one of the first cases for which the antigenic active region within the molecular structure of a clinically relevant inhalent has been recognized[2]. It has been proven by RAST inhibition, double immunodiffusion and a new allergoprint technique, based upon PAGE separation of insect crude extracts the immunological cross-reactivity between 14 chironomid species from different continents. Using isolated chironomid haemoglobins and sera of sensitized persons, as well as rabbit antibodies against larval crude extract or against the haemoglobin fraction of Chironomus thummi, it could be proven that cross-reactivity derives at least predominantly from haemoglobin components with common antigenic determinants in the different species[3]..

Reference

1. Baur, X., et al: Association of the immune response to chironomid allergen Chi t I with the HLA-D region. XIVth Congress of EAACI, Berlin, Sept. 17-22, 1989.

2. Baur X. Hemoglobins of chironomids: until now unknown potent inhalent antigens for humans (author's transl). Klin Wochenschr. 1980 Oct 15;58(20):1163-4.

3. Baur X, Dewair M, Haegele K, Prelicz H, Scholl A, Tichy H. Common antigenic determinants of haemoglobin as basis of immunological cross-reactivity between chironomid species (Diptera, Chironomidae): studies with human and animal sera. Clin Exp Immunol. 1983 Nov;54(2):599-607.

Γκέλης Ν.Δ. - Λεξικό Αλλεργίας - Εκδόσεις ΒΕΛΛΕΡOΦΟΝΤΗΣ - Κόρινθος 2013

Gelis Ν.D. - Dictionary of Allergies - VELLEROFONTIS Publications - Corinth 2013