Schmidt Mirko H H, Raulf-Heimsoth Monika, Posch Anton
Research Institute for Occupational Medicine of the Berufsgenossenschaften, Ruhr University, Department of Allergology/Immunology, Bochum, Germany.
Ann Allergy Asthma Immunol. 2002 Dec;89(6):613-8. doi: 10.1016/S1081-1206(10)62110-2.
Potential cross-reactions between natural rubber latex and fruit/vegetable specific immunoglobulin (Ig)E antibodies have been reported for many years. This study was designed to investigate the molecular basis of acquired food sensitization focusing on the storage protein patatin and the patatin-like latex protein Hev b 7.
The amount of potato-specific IgE in the serum of latex-allergic health care workers and children with atopic dermatitis was determined to evaluate cross-reactivity between Hev b 7 and patatin. Additionally, the stability of potato patatin to digestion was investigated.
Human serum was tested on its reactivity to latex and potato proteins by IgE immunoblotting after one-dimensional (1-D) and 2-D electrophoresis. Latex- and potato-specific IgE concentrations were measured in fluorescence enzyme immunoassays (CAP, Pharmacia, Uppsala, Sweden). Further, potato patatin was chromatographically isolated to perform auto-inhibition tests. Stability of patatin to degradation was determined by digestion in vitro.
Patatin was identified as major cross-reactive potato allergen by N-terminal sequencing. Seventy-five percent of the potato-sensitized people reacted with patatin in 1-D immunoblots, and 25% of the positive reactions to Hev b 7 could be blocked by preincubation of the patients' sera with purified potato patatin. Examination of children with atopic dermatitis showed that most sera contained patatin-specific IgE, whereas no Hev b 7-specific IgE was detected. Finally, patatin has been found partially stable to digestion in vitro.
Patatin was identified as a major cross-reactive protein in latex-associated potato allergy and appears to be relevant for atopic dermatitis. Therefore, patatin could be a suitable marker for the determination of potato sensitization, and it may also constitute an important food allergen. Cross-reactivity between Hev b 7 and patatin was restricted to primarily latex-sensitized adults, suggesting a different mechanism of sensitization in children with atopic dermatitis.
多年来一直有报道称天然橡胶乳胶与水果/蔬菜特异性免疫球蛋白（Ig）E抗体之间可能存在交叉反应。本研究旨在以储存蛋白马铃薯素和类马铃薯素乳胶蛋白Hev b 7为重点，研究获得性食物致敏的分子基础。
测定乳胶过敏医护人员和特应性皮炎患儿血清中马铃薯特异性IgE的含量，以评估Hev b 7与马铃薯素之间的交叉反应性。此外，还研究了马铃薯素对消化的稳定性。
通过一维（1-D）和二维（2-D）电泳后的IgE免疫印迹法检测人血清对乳胶和马铃薯蛋白的反应性。采用荧光酶免疫分析法（CAP，Pharmacia，瑞典乌普萨拉）测定乳胶和马铃薯特异性IgE浓度。此外，通过色谱法分离马铃薯素以进行自身抑制试验。通过体外消化测定马铃薯素对降解的稳定性。
通过N端测序确定马铃薯素是主要的交叉反应性马铃薯过敏原。75%的马铃薯致敏者在1-D免疫印迹中与马铃薯素发生反应，25%对Hev b 7的阳性反应可通过用纯化的马铃薯素预孵育患者血清来阻断。对特应性皮炎患儿的检查表明，大多数血清含有马铃薯素特异性IgE，而未检测到Hev b 7特异性IgE。最后，发现马铃薯素在体外对消化具有部分稳定性。
马铃薯素被确定为乳胶相关马铃薯过敏中的主要交叉反应性蛋白，似乎与特应性皮炎有关。因此，马铃薯素可能是测定马铃薯致敏的合适标志物，它也可能是一种重要的食物过敏原。Hev b 7与马铃薯素之间的交叉反应主要限于乳胶致敏的成年人，这表明特应性皮炎患儿的致敏机制不同。
