Docena G, Rozenfeld P, Fernández R, Fossati C A
Cátedra de Inmunología, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina.
Allergy. 2002 Feb;57(2):83-91. doi: 10.1034/j.1398-9995.2002.1o3219.x.
This study aimed the to investigate presence of residual allergenic cow's milk proteins (CMP) in some milk substitutes employed in the treatment of cow's milk allergy (CMA). These allergens may interfere with the treatment, and elicit allergic reactions in sensitized individuals.
The protein composition of the different extracts was evaluated by Lowry's method and tricine SDS-PAGE. Different immunoenzymatic methods were used (ELISA, EAST and immunoblotting) to quantify total serum IgE and specific serum IgE, as well as to detect the presence of antigenic and allergenic components.
The results showed a higher protein content in mammalian milks (cow, sheep, mare, goat, and human) than in hydrolyzed substitutes (partially or extensively hydrolyzed casein or whey proteins). Residual native, processed, or contaminant polypeptides have been identified in the moderate hydrolysates, whereas extensive hydrolysates did not show the presence of residual components by immunoblotting. However, specific antibodies with capacity to bind to peptides have been detected by EAST and ELISA, suggesting that extensive hydrolysates contain residual peptides that preserve immunoreactive epitopes. We were unable to demonstrate either residual antigenicity or allergenicity in an amino-acid-based formula.
Immunoenzymatic methods were used to detect the presence of cross-reactive components in mammalian milks. Residual allergenic components from cow's milk could be identified in both the moderate and extensive hydrolysates analyzed. This information may be relevant to the treatment of CMA.
本研究旨在调查用于治疗牛奶过敏（CMA）的一些牛奶替代品中残留的致敏性牛奶蛋白（CMP）的存在情况。这些过敏原可能会干扰治疗，并在致敏个体中引发过敏反应。
通过洛瑞法和三羟甲基氨基甲烷-十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（tricine SDS-PAGE）评估不同提取物的蛋白质组成。使用不同的免疫酶法（酶联免疫吸附测定法、免疫印渍法和免疫印迹法）来定量总血清免疫球蛋白E（IgE）和特异性血清IgE，以及检测抗原和致敏成分的存在情况。
结果显示，哺乳动物奶（牛奶、羊奶、马奶、山羊奶和人奶）中的蛋白质含量高于水解替代品（部分或完全水解的酪蛋白或乳清蛋白）。在中度水解物中鉴定出了残留的天然、加工或污染多肽，而通过免疫印迹法，深度水解物未显示出残留成分的存在。然而，通过免疫印渍法和酶联免疫吸附测定法检测到了具有与肽结合能力的特异性抗体，这表明深度水解物含有保留免疫反应性表位的残留肽。我们无法在氨基酸配方奶粉中证明残留的抗原性或致敏性。
使用免疫酶法检测哺乳动物奶中交叉反应成分的存在情况。在所分析的中度和深度水解物中均能鉴定出牛奶中的残留致敏成分。这一信息可能与CMA的治疗相关。
