Chirdo F G, Rumbo M, Añón M C, Fossati C A
Center for the Investigation and Development of Cryotechnology of Foods, Dept. of Immunology, School of Exact Sciences, UNLP, La Plata, Argentina.
Scand J Gastroenterol. 1998 Nov;33(11):1186-92. doi: 10.1080/00365529850172557.
Secretion of dietary antigens into breast milk has been extensively documented. The presence of these antigens is of relevance because they could be involved in the modulation of the immune response in neonates. The objective of this study is to determine the gliadin concentration in milk, colostrum, and serum samples from healthy lactating mothers on a normal diet. Gliadin levels in milk samples from a group of six mothers after a brief period of gluten restriction were also determined. The molecular weight of secreted gliadins was also analysed.
Gliadin concentration was determined with a highly sensitive competitive enzyme-linked immunosorbent assay, modified so as to eliminate anti-gliadin antibody interference. The level of gliadin/IgA anti-gliadin immune complexes in milk, colostrum, and serum samples was determined.
Gliadin was detected in all 49 milk samples. Its concentration varied between 5 and 1200 ng/ml (mean, 178 ng/ml). In colostrum (n = 14) gliadin levels were higher (range, 28-9000 ng/ml; mean, 883 ng/ml), not being detectable in one case. Gliadin was detectable in 14 of 31 serum samples, in which levels were lower than in milk and colostrum samples (mean, 41 ng/ml). Neither a correlation between gliadin levels in milk, colostrum, and serum samples from the same subject nor a relation between gluten intake and gliadin concentration in milk samples from six subjects under a 3-day gluten-free diet could be found. Higher levels of immune complexes were observed in colostrum samples than in milk and serum samples. No correlation was detected between gliadin concentration and the level of immune complexes. The analysis of milk and colostrum samples by immunoblotting showed bands of immunoreactive gliadin presenting Mr similar to those of native proteins from wheat extracts.
Very high levels of gliadin were detected in milk samples from healthy mothers on an unrestricted diet. Gliadin levels were higher than those reported for dietary antigens in other studies. Breast milk contained non-degraded gliadins and gliadin/anti-gliadin IgA immune complexes.
饮食抗原分泌至母乳中已有大量文献记载。这些抗原的存在具有相关性，因为它们可能参与新生儿免疫反应的调节。本研究的目的是测定正常饮食的健康哺乳期母亲的乳汁、初乳和血清样本中的麦醇溶蛋白浓度。还测定了一组六名母亲在短期限制麸质摄入后的乳汁样本中的麦醇溶蛋白水平。同时分析了分泌型麦醇溶蛋白的分子量。
采用高度灵敏的竞争性酶联免疫吸附测定法测定麦醇溶蛋白浓度，并进行改良以消除抗麦醇溶蛋白抗体干扰。测定乳汁、初乳和血清样本中麦醇溶蛋白/抗麦醇溶蛋白IgA免疫复合物的水平。
在所有49份乳汁样本中均检测到麦醇溶蛋白。其浓度在5至1200 ng/ml之间（平均为178 ng/ml）。初乳（n = 14）中的麦醇溶蛋白水平更高（范围为28至9000 ng/ml；平均为883 ng/ml），有一例未检测到。在31份血清样本中的14份中可检测到麦醇溶蛋白，其水平低于乳汁和初乳样本（平均为41 ng/ml）。未发现同一受试者的乳汁、初乳和血清样本中的麦醇溶蛋白水平之间存在相关性，也未发现6名受试者在3天无麸质饮食期间的麸质摄入量与乳汁样本中的麦醇溶蛋白浓度之间存在关联。初乳样本中的免疫复合物水平高于乳汁和血清样本。未检测到麦醇溶蛋白浓度与免疫复合物水平之间存在相关性。通过免疫印迹法对乳汁和初乳样本进行分析，结果显示免疫反应性麦醇溶蛋白条带的分子量与小麦提取物中的天然蛋白相似。
在饮食不受限制的健康母亲的乳汁样本中检测到非常高水平的麦醇溶蛋白。麦醇溶蛋白水平高于其他研究中报道的饮食抗原水平。母乳中含有未降解的麦醇溶蛋白和麦醇溶蛋白/抗麦醇溶蛋白IgA免疫复合物。
