ABSTRACT
Background@#Hen’s egg white (HEW) is the most common cause of food allergy in children which induces mild to fatal reactions. The consultation for a proper restriction is important in HEW allergy. We aimed to identify the changes in HEW allergenicity using diverse cooking methods commonly used in Korean dishes. @*Methods@#Crude extract of raw and 4 types of cooked HEW extracts were produced and used for sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE), enzyme-linked immunosorbent assay (ELISA), and ELISA inhibition assays using 45 serum samples from HEW allergic and tolerant children. Extracts were prepared; scrambled without oil for 20–30 seconds in frying pan without oil, boiled at 100°C for 15 minutes, short-baked at 180°C for 20 minutes, and long-baked at 45°C for 12 hours with a gradual increase in temperature up to 110°C for additional 12 hours, respectively. @*Results@#In SDS-PAGE, the intensity of bands of 50–54 kDa decreased by boiling and baking.All bands almost disappeared in long-baked eggs. The intensity of the ovalbumin (OVA) immunoglobulin E (IgE) bands did not change after scrambling; however, an evident decrease was observed in boiled egg white (EW). In contrast, ovomucoid (OM) IgE bands were darker and wider after scrambling and boiling. The IgE binding reactivity to all EW allergens were weakened in short-baked EW and considerably diminished in long-baked EW. In individual ELISA analysis using OVA+OM+ serum samples, the median of specific IgE optical density values was 0.435 in raw EW, 0.476 in scrambled EW, and 0.487 in boiled EW. Conversely, it was significantly decreased in short-baked (0.406) and long-baked EW (0.012). Significant inhibition was observed by four inhibitors such as raw, scrambled, boiled and short-baked HEW, but there was no significant inhibition by long-baked HEW (IC50 > 100 mg/mL). @*Conclusion@#We identified minimally reduced allergenicity in scrambled EW and extensively decreased allergenicity in long-baked EW comparing to boiled and short-baked EW as well as raw EW. By applying the results of this study, we would be able to provide safer dietary guidence with higher quality to egg allergic children.
ABSTRACT
Purpose@#Perilla seed (PS) is the most common cause of seed-induced anaphylaxis in Korean children, but the reports on PS allergy, including phenotype and cross-reactivity, are rare. The aim of this study is to assess the clinical characteristics of PS allergy and investigate cross-reactivity with sesame seed (SS). @*Methods@#Through a retrospective medical record review, patients with clinical PS allergy were identified in a single tertiary hospital. Clinical characteristics of allergic reaction upon exposure to PS and SS, results of skin prick test (SPT) to PS and SS, and the levels of serum SS-specific immunoglobulin E (SS-sIgE) were investigated. Cross-reactivity between PS and SS was studied using IgE enzymelinked immunosorbent assay (ELISA) inhibition. @*Results@#The median age of 34 PS-allergic children was 41.5 months (range, 10 months to 12 years), and the proportion of anaphylaxis upon exposure to PS was 29.4% (n = 10). The PS SPT was positive in 94.1% (n = 32) with the median wheal size of 6.25 mm. Among PS-allergic children, the percentages of patients with positive symptoms, negative symptoms, and indeterminate symptoms upon exposure to SS were 8.8%, 41.2%, and 50%, respectively. Out of 14 PS-allergic children who were tolerant to SS, positive sensitization to SS was noticed in 78.6% by serum SS-sIgE, and 57.1% by SS SPT. Partial cross-reactivity between PS and SS was identified in IgE ELISA inhibition. @*Conclusion@#This study reported the clinical profiles and SPT results in a relatively large number of PS-allergic children and identified the partial cross-reactivity between PS and SS for the first time.