Antigenicity of an aphid allergen in respiratory allergic diseases / 천식및알레르기

ABSTRACT

BACKGROUND: Several inhalant allergens are newly identified from arthropods including insects or arachnids recently. Aphids (Heteroptera Aphididae) are widespread sucking insects, which are parasitic on numerous host plants such as various crops, trees and weeds. Among aphids, Aphis gossypii is a particularly polyphagous species that has been described on almost 300 host plants from various botanical families. Thus A. gossypii is found throughout the country and is a species anyone can easily contact. It is unknown whether aphids have a role in the pathogenesis of respiratory allergy. OBJECTIVE: We assumed that aphids can act as an inhalant allergen on the hypothesis that numerous allergenic materials are released from aphids and become airborne. Using a representative species, A. gossypii, this study was performed to evaluate the antigenicity of an aphid allergen in patients with respiratory allergic diseases. METHODS: Skin prick test with crude extracts of A. gossypii and 50 common inhalant allergens was performed for 225 subjects with respiratory allergic diseases (bronchial asthma and/or rhinitis). A. gossypii-specific IgE (sIgE) were detected by means of ELISA, and IgE- binding components were identified by SDS-PAGE with immunoblot analysis. RESULTS: Of the 225 enrolled subjects, 37 (16.4%) subjects showed positive skin reactivity to A. gossypii. Of them, 17 (7.6%) subjects had A. gossypii-sIgE by ELISA. The SDS-PAGE of A. gossypii extracts showed various protein bands ranging from 9 to 200 kd. Of them, diverse IgE-binding pattern was noted for individual subject by immunoblot analysis. The inhibitory ELISA results indicated that IgE binding to A. gossypii was partially inhibited by the allergenic extracts of house dust mite (HDM), cockroach, or other aphid (Acyrthosiphon kondoi). Finally, A. gossypii-bronchial challenge test was conducted for one asthmatic farmer with skin reactivity to A. gossypii and strong job-related symptoms, but showed no significant response. CONCLUSION: A. gossypii can elicit IgE response in some patients with respiratory allergic diseases. A. gossypii may have a cross-reactivity with HDM and cockroach. Further study will be needed to evaluate its clinical significance in respiratory allergy patients.