Jiang Bingjun, Qu Hong, Hu Yuanlei, Ni Ting, Lin Zhongping
College of Life Sciences, National Lab of Protein Engineering and Genetic Engineering of Plants, Peking University, Beijing 100871, PR China.
BMC Bioinformatics. 2007 Oct 9;8:375. doi: 10.1186/1471-2105-8-375.
Safety assessment of genetically modified (GM) food, with regard to allergenic potential of transgene-encoded xenoproteins, typically involves several different methods, evaluation by digestibility being one thereof. However, there are still debates about whether the allergenicity of food allergens is related to their resistance to digestion by the gastric fluid. The disagreements may in part stem from classification of allergens only by their sources, which we believe is inadequate, and the difficulties in achieving identical experimental conditions for studying digestion by simulated gastric fluid (SGF) so that results can be compared. Here, we reclassify allergenic food allergens into alimentary canal-sensitized (ACS) and non-alimentary canal-sensitized (NACS) allergens and use a computational model that simulates gastric fluid digestion to analyze the digestibilities of these two types.
The model presented in this paper is as effective as SGF digestion experiments, but more stable and reproducible. On the basis of this model, food allergens are satisfactorily classified as ACS and NACS types by their pathways for sensitization; the former are relatively resistant to gastric fluid digestion while the later are relatively labile.
The results suggest that it is better to classify allergens into ACS and NACS types when understanding the relationship between their digestibility and allergenicity and the digestibility of a target foreign protein is a parameter for evaluating its allergenicity during safety assessments of GM food.
对于转基因食品的安全性评估,就转基因编码的异种蛋白的致敏潜力而言,通常涉及几种不同的方法,其中之一是通过消化性评估。然而,关于食物过敏原的致敏性是否与其对胃液消化的抗性有关,仍然存在争议。这些分歧可能部分源于仅根据过敏原的来源进行分类,我们认为这种分类方式并不充分,以及在模拟胃液(SGF)消化研究中难以实现相同的实验条件以便比较结果。在此,我们将致敏性食物过敏原重新分类为消化道致敏(ACS)和非消化道致敏(NACS)过敏原,并使用模拟胃液消化的计算模型来分析这两种类型的消化性。
本文提出的模型与SGF消化实验一样有效,但更稳定且可重复。基于该模型,食物过敏原根据其致敏途径被令人满意地分类为ACS和NACS类型;前者对胃液消化相对抗性较强,而后者相对不稳定。
结果表明,在理解过敏原的消化性与其致敏性之间的关系时,将过敏原分类为ACS和NACS类型更好,并且在转基因食品安全性评估中,目标外源蛋白的消化性是评估其致敏性的一个参数。