Data_Sheet_3_Occupational Allergic Sensitization Among Workers Processing King Crab (Paralithodes camtschaticus) and Edible Crab (Cancer pagurus) in Norway and Identification of Novel Putative Allergenic Proteins.xlsx

Introduction: Asthma and allergy occur frequently among seafood processing workers, with the highest prevalence seen in the crustacean processing industry. In this study we established for the first time the prevalence of allergic sensitization in the Norwegian king- and edible crab processing industry and characterized the IgE-reactive proteins.
Materials and Methods: Two populations of crab processing workers participated; 119 king crab and 65 edible crab workers. The investigation included information on work tasks and health through a detailed questionnaire. Allergic sensitization was investigated by crab-specific IgE quantification and skin prick tests (SPT) to four in-house prepared crab extracts; raw meat, cooked meat, raw intestines and raw shell. Allergen-specific IgE binding patterns were analyzed by IgE immunoblotting to the four allergen extracts using worker serum samples. Total proteins in crab SPT extracts and immunoblot-based IgE binding proteins were identified by mass spectrometric analysis.
Results: Positive SPTs were established in 17.5% of king- and 18.1% of edible crab workers, while elevated IgE to crab were demonstrated in 8.9% of king- and 12.2% of edible crab processing workers. There was no significant difference between the king and edible crab workers with respect to self-reported respiratory symptoms, elevated specific IgE to crab or SPT results. Individual workers exhibited differential IgE binding patterns to different crab extracts, with most frequent binding to tropomyosin and arginine kinase and two novel IgE binding proteins, hemocyanin and enolase, identified as king- and edible crab allergens.
Conclusions: Occupational exposure to king- and edible crabs may frequently cause IgE mediated allergic sensitization. Future investigations addressing the diagnostic value of crab allergens including tropomyosin and arginine kinase and the less well-known IgE-binding proteins hemocyanin and enolase in a component-resolved diagnostic approach to crab allergy should be encouraged.

引言：海鲜加工工人中哮喘与过敏的发病率较高，其中甲壳类动物加工业的患病率居于首位。本研究首次明确了挪威帝王蟹与食用蟹加工业工人的过敏致敏率，并对IgE反应性蛋白进行了表征。
材料与方法：本研究纳入两类蟹类加工工人人群：119名帝王蟹加工工人与65名食用蟹加工工人。研究通过详细问卷调查收集了工人的工作任务与健康相关信息。采用蟹类特异性IgE定量检测以及针对四种室内制备的蟹类提取物（生蟹肉、熟蟹肉、生蟹肠及生蟹壳）的皮肤点刺试验（skin prick tests, SPT），对工人的过敏致敏情况进行评估。利用工人血清样本，通过IgE免疫印迹（immunoblotting）技术分析四种过敏原提取物的过敏原特异性IgE结合模式。通过质谱分析（mass spectrometric analysis）鉴定蟹类皮肤点刺试验提取物中的总蛋白，以及免疫印迹检测到的IgE结合蛋白。
结果：帝王蟹加工工人中17.5%的皮肤点刺试验结果呈阳性，食用蟹加工工人中这一比例为18.1%；同时，帝王蟹加工工人中8.9%的蟹类特异性IgE水平升高，食用蟹加工工人中这一比例为12.2%。在自我报告的呼吸道症状、蟹类特异性IgE升高水平以及皮肤点刺试验结果方面，帝王蟹与食用蟹加工工人之间无显著差异。个体工人对不同蟹类提取物的IgE结合模式存在差异，其中与原肌球蛋白（tropomyosin）、精氨酸激酶（arginine kinase）结合最为频繁，此外还鉴定出两种新型IgE结合蛋白——血蓝蛋白（hemocyanin）与烯醇化酶（enolase），可作为帝王蟹与食用蟹的过敏原。
结论：职业暴露于帝王蟹与食用蟹可能频繁引发IgE介导的过敏致敏反应。未来应鼓励开展相关研究，以原肌球蛋白、精氨酸激酶以及鲜为人知的IgE结合蛋白血蓝蛋白与烯醇化酶等蟹类过敏原为对象，通过组分分辨诊断（component-resolved diagnostic）方法评估其在蟹类过敏诊断中的应用价值。