Serum specific IgE reactivity to recombinant Der f 11 in asthmatic children

This study was designed to examine the prevalence of positive serum IgE rea ctivity to the recombinant group 11 Dermatophagoides farinae allergen (rDer f 11) in asthmatic children in Taiwan. Using immunoblot analysis in a preli minary study of 18 asthmatic children, 13 (72.2%) reacted positively to rDe rf 11 and 16 (88.9%) showed positive reactivity to D. farinae extracts. The allergenicity of rDerf 11 was further evaluated with in vivo skin tests an d in vitro IgE immunodot assays in 24 mite skin-test-positive asthmatic chi ldren. Whereas 17 (70.8%) had positive skin tests to rDer f 11, 18 (75.0%) had positive serum IgE reactivity to rDerf 11. A good coincidence (87.5%) b etween the immunodot assay and the skin test was confirmed in these asthmat ic children. Moreover, the prevalence of serum IgE reactivity to rDerf I I was further investigated in a large panel of 49 mite skin-test-positive ast hmatic children. Again, 38 (77.6%) had positive serum IgE reactivity to rDe r f I I in immunodot assays. Taken together, the positive IgE reactivity to rDerf I I in immunodot analysis ranged from 75 to 77.6% in two groups of 7 3 mite skin-test-positive asthmatic children. High incidence of serum IgE a ntibodies specific for rDerf 11 in the present study suggests that Derf 11 is a novel major allergen of house dust mites.