IgE Binding Pattern to Dermatophagoides Pteronyssinus in Younger and Older Asthmatic Children : An IgE Imnlunoblot Analysis

Abstract

House dust mite is the most important causative allergens of childhood asthma and its

positive rate of allergy skin test reaches up to 80% in atopic asthmatic children in

Korea. Although the mite sensitization is more significant in older children(>4 years), it

is also important in some younger(<4 years) asthmatic children. To identify the major

allergens in Korean atopic asthmatic children and find the variations of IgE binding

pattern to Dermatophagoides pteronyssinus(Dp) in younger and older age groups, we

conducted IgE immunoblot.

Sera were collected in 25 children with Dp-sensitive atopic asthma : Group Ⅰ

(younger children aged 1-3), Goup Ⅱ(older children aged 4-12). Using our own-made

crude Dp extract, we conducted IgE- immunoblot (biotin-avidine-phosphatase system).

In the group Ⅰ, the 15KD protein was significantly bound by 69.2%(9/13) of sera and

98KD, 59KD, 31KD, 25KD components were bound by 8-16% of sera, respectively. In

the group Ⅱ, the 15KD and 25KD proteins were significantly bound Immunoblot by

100% and 67% of sera, and 18KD, 94KD by 33%, 98KD by 25%, 45KD by 8% of sera,

respectively.

In conclusion, the 15KD protein is the most prevalent IgE-binding antigen in all age

groups, on the other hands, IgE-sensitization to 25KD component is confirmed mainly in

the cases of older age group in this study.