Ju H R, Okumiya M, Nishizono S, Ki M, Sugano M, Imaizumi K
Laboratory of Nutrition Chemistry, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
Food Chem Toxicol. 1997 Jul;35(7):663-8. doi: 10.1016/s0278-6915(97)00031-8.
The allergenicity of two types of whey protein hydrolysates-bacterial protease hydrolysed whey protein (BHW) with a molecular mass less than 3500 and trypsin hydrolysed whey protein (THW) with a molecular mass less than 6500-was compared with that of whey protein concentrate (WPC) or beta-lactoglobulin (beta-LG) in vivo by their ability to release rat chymase II (RChyII), an indicator of mucosal mast cell degranulation in the intestine. Antigen-specific reaginic activity and immunoglobulin (Ig)G in serum were markedly lower in rats primed with BHW than in those with WPC or beta-LG, although these were not lowered in THW-primed rats. In contrast, rats primed with either hydrolysate and subsequently orally challenged with the primed antigen increased the release of RChyII to a greater extent than did rats primed and challenged with the native proteins. The extent of the release was primarily attributed to the nature of primed rather than challenged antigen. These results indicate that determination of circulatory RChyII is a sensitive in vivo method to evaluate the allergenicity of milk protein hydrolysates. The improper hydrolysis of dietary protein may enhance allergic reactions.
通过测定大鼠糜酶II（RChyII，肠道黏膜肥大细胞脱颗粒的一个指标）的释放能力，在体内比较了两种乳清蛋白水解产物（分子量小于3500的细菌蛋白酶水解乳清蛋白（BHW）和分子量小于6500的胰蛋白酶水解乳清蛋白（THW））与乳清蛋白浓缩物（WPC）或β-乳球蛋白（β-LG）的致敏性。用BHW致敏的大鼠血清中抗原特异性反应素活性和免疫球蛋白（Ig）G明显低于用WPC或β-LG致敏的大鼠，不过用THW致敏的大鼠中这些指标并未降低。相反，用任何一种水解产物致敏并随后经口给予致敏抗原攻击的大鼠，其RChyII的释放程度比用天然蛋白质致敏并攻击的大鼠更高。释放程度主要归因于致敏抗原而非攻击抗原的性质。这些结果表明，测定循环中的RChyII是评估乳清蛋白水解产物致敏性的一种灵敏的体内方法。膳食蛋白质的不当水解可能会增强过敏反应。
