College of Food Science and Engineering, Ocean University of China, No.5, Yushan Road, Qingdao, Shandong Province 266003, P. R. China.
Technology Center of Qingdao Customs District, No.70 Qutangxia Road, Qingdao, Shandong Province 266002, P. R. China.
J Agric Food Chem. 2020 Oct 14;68(41):11553-11567. doi: 10.1021/acs.jafc.0c03840. Epub 2020 Oct 5.
Tropomyosin (TM) is the major shrimp allergen that could trigger anaphylactic reactions. Recently, recombinant TM (rTM) has been accepted widely in the field of allergen-specific immunotherapy, but the allergenicity of rTM has not been compared with natural TM (nTM) based on an digestion profile. In this work, IgG-/IgE binding, allergen peptides, and degranulation ability of the digested samples in simulated gastric fluid/simulated intestinal fluid/gastrointestinal models from nTM and rTM were evaluated by immunoassays, proteomics, and basophil degranulation assay. Results showed that pepsin-digested and trypsin-digested samples of rTM exhibited lower IgG-/IgE binding and degranulation than those of nTM. More peptides of the digested samples from rTM (57.8%) matched shrimp allergic epitopes than those from nTM (33.3%). However, the peptide SITDELDQTF (269-278) appeared most frequently. These findings would supply foundation data for epitope-based immunotherapy to shrimp allergic individuals.
原肌球蛋白(TM)是主要的虾过敏原,可引发过敏反应。最近,重组 TM(rTM)已在过敏原特异性免疫治疗领域得到广泛认可,但尚未基于消化谱比较 rTM 与天然 TM(nTM)的变应原性。在这项工作中,通过免疫分析、蛋白质组学和嗜碱性粒细胞脱颗粒试验评估了 nTM 和 rTM 在模拟胃液/模拟肠液/胃肠道模型中消化后的样品的 IgG-/IgE 结合、过敏原肽和脱颗粒能力。结果表明,胃蛋白酶和胰蛋白酶消化后的 rTM 样品的 IgG-/IgE 结合和脱颗粒能力低于 nTM。rTM 消化样品中有更多的肽(57.8%)与虾过敏表位匹配,而 nTM 中只有 33.3%。然而,肽 SITDELDQTF(269-278)出现的频率最高。这些发现为基于表位的免疫疗法治疗虾过敏个体提供了基础数据。