Faculty of Chemistry-Innovation Center d.o.o., 11000, Belgrade, Serbia.
Institute for Risk Assessment Sciences, Immunotoxicology Group, Utrecht University, 3584 CM, Utrecht, The Netherlands.
Mol Nutr Food Res. 2018 Sep;62(17):e1800341. doi: 10.1002/mnfr.201800341. Epub 2018 Jul 29.
During food processing, the Maillard reaction (МR) may occur, resulting in the formation of glycated proteins. Glycated proteins are of particular importance in food allergies because glycation may influence interactions with the immune system. This study compared native and extensively glycated milk allergen β-lactoglobulin (BLG), in their interactions with cells crucially involved in allergy.
BLG was glycated in MR and characterized. Native and glycated BLG were tested in experiments of epithelial transport, uptake and degradation by DCs, T-cell cytokine responses, and basophil cell degranulation using ELISA and flow cytometry. Glycation of BLG induced partial unfolding and reduced its intestinal epithelial transfer over a Caco-2 monolayer. Uptake of glycated BLG by bone marrow-derived dendritic cells (BMDC) was increased, although both BLG forms entered BMDC via the same mechanism, receptor-mediated endocytosis. Once inside the BMDC, glycated BLG was degraded faster, which might have led to observed lower cytokine production in BMDC/CD4 T-cells coculture. Finally, glycated BLG was less efficient in induction of degranulation of BLG-specific IgE sensitized basophil cells.
This study suggests that glycation of BLG by MR significantly alters its fate in processes involved in immunogenicity and allergenicity, pointing out the importance of food processing in food allergy.
在食品加工过程中，美拉德反应（MR）可能发生，导致糖化蛋白的形成。糖化蛋白在食物过敏中尤为重要，因为糖化可能影响与免疫系统的相互作用。本研究比较了天然和广泛糖化的牛奶过敏原β-乳球蛋白（BLG），在与过敏中关键涉及的细胞相互作用方面。
MR 中糖化 BLG 并对其进行了表征。使用 ELISA 和流式细胞术，在体外实验中检测了天然和糖化 BLG 对上皮细胞转运、摄取和降解的影响，以及对 DC 细胞、T 细胞细胞因子反应和嗜碱性粒细胞脱颗粒的影响。BLG 的糖化诱导了部分展开，并减少了其在 Caco-2 单层上的肠道上皮转移。尽管两种 BLG 形式都通过相同的机制，即受体介导的内吞作用进入 BMDC，但骨髄来源的树突状细胞（BMDC）摄取糖化 BLG 的增加。一旦进入 BMDC，糖化 BLG 降解更快，这可能导致在 BMDC/CD4 T 细胞共培养中观察到的细胞因子产生降低。最后，糖化 BLG 在诱导 BLG 特异性 IgE 致敏嗜碱性粒细胞脱颗粒方面的效率较低。
本研究表明，MR 对 BLG 的糖化显著改变了其在免疫原性和变应原性过程中的命运，指出了食品加工在食物过敏中的重要性。
