RESUMEN
PURPOSE: This study investigated the differences in the profile of IgE-binding components between Dermatophagoides pteronyssinus (Dp) and Dermatophagoides farina (Df) in respiratory allergic patients sensitized to Dp/Df. METHODS: Eighteen patients with respiratory allergic diseases having higher levels of serum specific IgE to Df compared to those to Dp (>twice) were enrolled. IgE-immunoblot analysis using Dp and Df extracts were used to compare the IgE binding components. Study subjects were classified into 2 groups according to the results of IgE-immunoblot analysis: 6 subjects having IgE-binding components to group 1 and 2 allergens (group B) and 12 subjects not having them (group A). RESULTS: Group A subjects were older (47.92±8.51 vs. 35.50±11.10, P=0.039) and males were dominant (75% vs. 0% P=0.009). IgE-immunoblot analysis demonstrated that all the group B subjects had IgE bindings to 2 major components, 14 and 25 kDa, while group A subjects had IgE bindings to high-molecular weight components ranging from 60-98 kDa. The enzyme-linked immunosorbent assay inhibition test showed a significant inhibition with additions of Df, not with Dp in group B subjects. Serum specific IgE levels to Dp and Df were significantly higher in group B than in group A, while its ratio (Df to Dp) was significantly higher in group A. No differences were noted in clinical parameters, total IgE, or eosinophil cationic protein levels. CONCLUSION: Heterogeneity of IgE binding patterns to Dp and Df extracts was noted according to the ratio of serum specific IgE (Df/Dp).