School of Food Science and Technology, National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian 116034, P. R. China.
Liaoning Engineering Research Center of Special Dietary Food, Dalian Polytechnic University, Dalian 116034, P. R. China.
J Agric Food Chem. 2023 Nov 8;71(44):16739-16751. doi: 10.1021/acs.jafc.3c04999. Epub 2023 Oct 28.
Although tropomyosin has been identified as a major allergen in Antarctic krill, the digestive fate of Antarctic krill tropomyosin and its relationship with allergenicity are unknown. In this study, Antarctic krill tropomyosin was administered to BALB/c mice both gavage and intraperitoneal injection to explore its sensitizing and eliciting capacity, and its digestion products were analyzed for structural changes and digestion-resistant linear epitopes. Mice gavaged with tropomyosin exhibited lower levels of specific IgE and IgG, mast cell degranulation, vascular permeability, and anaphylaxis symptoms than those in the intraperitoneal injection group. This may be due to the destruction of macromolecular aggregates, loose expansion of the tertiary structure, complete disappearance of α-helix, and significant changes in molecular force upon the digestion of tropomyosin. Nevertheless, the intragastric administration of Antarctic krill tropomyosin still triggered strong allergic reactions, which was attributed to the existence of seven digestion-resistant linear epitopes (Glu26-His44, Thr111-Arg125, Glu157-Glu164, Glu177-Gly186, Val209-Ile225, Arg244-Arg255, and Val261-Ile270).
尽管肌球蛋白轻链已被鉴定为南极磷虾的主要过敏原，但南极磷虾肌球蛋白的消化命运及其与变应原性的关系尚不清楚。在这项研究中，通过灌胃和腹腔注射将南极磷虾肌球蛋白给予 BALB/c 小鼠，以探索其致敏和激发能力，并分析其消化产物的结构变化和消化抗性线性表位。与腹腔注射组相比，经肌球蛋白灌胃的小鼠的特异性 IgE 和 IgG、肥大细胞脱颗粒、血管通透性和过敏症状水平较低。这可能是由于肌球蛋白消化导致大分子聚集体的破坏、三级结构的松散扩展、α-螺旋的完全消失以及分子力的显著变化。然而，南极磷虾肌球蛋白的胃内给药仍引发强烈的过敏反应，这归因于存在七个消化抗性线性表位（Glu26-His44、Thr111-Arg125、Glu157-Glu164、Glu177-Gly186、Val209-Ile225、Arg244-Arg255 和 Val261-Ile270）。
