Food and Biobased Research, Wageningen University and Research, Wageningen, The Netherlands.
Laboratory of Food Chemistry, Wageningen University and Research, Wageningen, The Netherlands.
PLoS One. 2020 Aug 14;15(8):e0236212. doi: 10.1371/journal.pone.0236212. eCollection 2020.
Although an impact of processing on immunogenicity of food proteins has clearly been demonstrated, the underlying mechanisms are still unclear. We applied 3 different processing methods: wet heating (60 °C) and low- or high-temperature (50 °C or 130 °C, respectively) dry-heating in absence or presence of reducing sugars, to β-lactoglobulin (BLG), lysozyme and thyroglobulin, which represent dietary proteins with different pI or molecular weight. Uptake of the soluble fraction of the samples was tested in two types of, genetically homogeneous, antigen-presenting cells (macrophages and dendritic cells derived from THP-1 monocytes). This revealed a strong correlation between the uptake of the different protein samples by macrophages and dendritic cells, and confirmed the key role of hydrophobicity, over aggregation, in determining the uptake. Several uptake routes were shown to contribute to the uptake of BLG by macrophages. However, cytokine responses following exposure of macrophages to BLG samples were not related to the levels of uptake. Together, our results demonstrate that heat-treatment-induced increased hydrophobicity is the prime driving factor in uptake, but not in cytokine production, by THP-1 macrophages.
虽然加工对食物蛋白质免疫原性的影响已经得到明确证实，但潜在的机制仍不清楚。我们应用了 3 种不同的加工方法：湿式加热（60°C）和低或高温（50°C 或 130°C，分别）干式加热，分别在存在或不存在还原糖的情况下，处理β-乳球蛋白（BLG）、溶菌酶和甲状腺球蛋白，它们分别代表具有不同等电点或分子量的膳食蛋白质。我们在两种类型的遗传同质、抗原呈递细胞（巨噬细胞和树突状细胞，源自 THP-1 单核细胞）中测试了样品可溶性部分的摄取。这表明巨噬细胞和树突状细胞对不同蛋白质样品的摄取之间存在很强的相关性，并证实了疏水性、聚集过度在决定摄取方面的关键作用。研究表明，几种摄取途径有助于巨噬细胞摄取 BLG。然而，巨噬细胞暴露于 BLG 样品后细胞因子反应与摄取水平无关。总之，我们的研究结果表明，热处理诱导的疏水性增加是 THP-1 巨噬细胞摄取的主要驱动因素，但不是细胞因子产生的主要驱动因素。
