Reduction of Antigenicity and Allergenicity of Hen's Egg White by High Pressure Treatment for Prevention of Food Allergy

背景：鸡蛋过敏是婴幼儿直接食物过敏反应最常见的原因之一。卵泡样蛋白（gald1， OVM）是一种主要的源自蛋清的过敏原。如果能通过高压处理选择性地改变OVM的生物活性，则可用于生产低致敏性食品。在这项研究中，研究了高压治疗对OVM的致敏性和结构的影响。方法：将样品在100-600 MPa压力下，在10℃下加压10 min。用血清IgE抗体和抗原致敏的人嗜碱性细胞样细胞系KU812F释放的β-己糖氨酸酶[E.C.3.2.1.52]活性评价其致敏性。在获得患者知情同意后，使用5例蛋清过敏患者对OVM的RAST评分较高的患者和1名健康志愿者的血清。在0.1 ~ 400mpa的压力下测量荧光光谱。通过确定光谱质心<v>，定量了荧光光谱。结果：β-己糖氨酸酶释放量在0.1 ~ 400 MPa范围内随压力升高而逐渐降低，在更高压力下释放量增加。在400mpa的压力下，观察到致敏性显著降低50-90%。荧光强度随压力升高而升高。与原生态OVM相比，最大波长红移了2 ~ 8 nm。这表明酪氨酸残基周围的极性增加，疏水核暴露在分子表面。<v>值降低2.0 ~ 3.0 ^*100 （cm^<-1>）。随后的压力降低使<v>值增加了0.1 ~ 1.2 ^*100 （cm^<-1>）。这些结果表明高压引起了第三系结构的不可逆变化。结论：高压对致敏性的降低可能是由于OVM构象的展开。高压处理是降低OVM致病性的有效食品加工技术。少

Background : Egg allergy is one of the most frequent causes of immediate food-allergic reactions in infant and young children. Ovomucoid (Gal d 1, OVM) is a major allergen derived from egg white. If the biological activities of OVM can be selectively modified by high pressure treatment, it is useful for the production of low allergenic foods. In this study, the effects of high pressure treatment on an allergenicity and structure of OVM were investigated.Methods : The sample was pressurized under the pressures at 100-600 MPa at 10℃ for 10 min. The allergenicity was evaluated on the basis of β-hexosaminidase [E.C.3.2.1.52] activity released from the human basophile like cell line KU812F sensitized with serum IgE antibody and antigen. Sera from 5 patients with egg white allergies having high RAST scores to OVM and a healthy volunteer were used after obtaining informed consent from the patients. The fluorescence spectroscopy was measured under pressure from 0.1 to 400 MPa. The fluorescence … More spectra was quantified by specifying the center of spectral mass<v>.Results : The releases of β-hexosaminidase were decreased gradually with elevating pressure from 0.1 to 400 MPa and were increased at higher pressures. Significant decreases in allergenicities, 50-90%, were observed in the pressurised OVM at 400 MPa. The fluorescence intensities were increased with elevating pressure. The maximum wavelengths were red-shifted by 2 nm to 8 nm, compared with the native OVM. This indicates that the polarity around the tyrosin residues increase and the hydrophobic cores are exposed to the surface of the molecules. The <v> values were decreased by 2.0 to 3.0 ^*100 (cm^<-1>). The subsequent pressure decrease increased the <v> values by 0.1 to 1.2 ^*100 (cm^<-1>). These results suggest that the high pressure induced irreversible changes in the tertiary structure.Conclusion : The reduction of allergenicity by high pressure seems due to the unfolding of the conformation of OVM. High pressure treatment could be effective food processing technique to reduce the allegenicity of OVM. Less