用于评估“低敏”婴儿配方奶粉中残留抗原活性的抗牛奶酪蛋白成分的单克隆抗体和多克隆抗体。

Plebani A, Restani P, Naselli A, Galli C L, Meini A, Cavagni G, Ugazio A G, Poiesi C

Department of Paediatrics, Institute G. Gaslini, University of Genova, Italy.

Clin Exp Allergy. 1997 Aug;27(8):949-56.

BACKGROUND

Hydrolysed casein and whey protein formulas have been developed with the aim of preventing sensitization in infants at high risk of cow milk allergy. Subsequently these products have also been used for treatment of children with cow milk allergy. However, severe reactions have occurred in some allergic infants fed with these formulas raising doubts about their absolute safety and suggest the need for developing in vitro techniques for detection of eventual residual allergenic activity in such preparations.

OBJECTIVES

Our purpose was to evaluate the usefulness of monoclonal and polyclonal antibodies against casein components (alpha, beta and kappa casein) as reagents for the detection of the residual antigenic activity of casein components in several hydrolysed formulas.

METHODS

The monoclonal and polyclonal antibodies were produced according to standard procedures by immunizing female Balb/c mice with casein fraction (a mixture of alpha, beta and kappa casein). ELISA assays were developed to test the specificity of the antibodies and to detect and evaluate the amount of residual antigenic activity of the casein components in hydrolysed formulas.

RESULTS

Use of polyclonal antiserum specific for casein allowed detection of residual antigenic activity of casein components in all partial hydrolysates and in the two extensive whey protein hydrolysates in the amounts ranging from 0.05 to 0.67% of total protein. No such activity was detectable in either the two extensive casein hydrolysates tested or the aminoacid based formula. The polyclonal antiserum proved to be more suitable than monoclonals for detecting residual antigenic activity in the hydrolysates. The monoclonal antibodies were directed against epitopes expressed on different casein components.

CONCLUSIONS

In this study the ELISA inhibition assay with polyclonal antibodies specific for casein components of cow milk proved to be a sensitive method for estimating residual antigenicity in the hydrolysed formulas commercially available for infants with cow milk allergy suggesting their potential application for the quality control of hypoallergenic infant formulas.

背景

已开发出酪蛋白水解物和乳清蛋白配方奶粉，旨在预防牛奶过敏高危婴儿的致敏反应。随后，这些产品也被用于治疗牛奶过敏儿童。然而，一些食用这些配方奶粉的过敏婴儿出现了严重反应，这引发了对其绝对安全性的质疑，并表明需要开发体外技术来检测此类制剂中最终残留的致敏活性。

目的

我们的目的是评估抗酪蛋白成分（α、β和κ酪蛋白）的单克隆抗体和多克隆抗体作为检测几种水解配方奶粉中酪蛋白成分残留抗原活性试剂的实用性。

方法

通过用酪蛋白组分（α、β和κ酪蛋白的混合物）免疫雌性Balb/c小鼠，按照标准程序制备单克隆抗体和多克隆抗体。开发酶联免疫吸附测定（ELISA）来测试抗体的特异性，并检测和评估水解配方奶粉中酪蛋白成分残留抗原活性的量。

结果

使用对酪蛋白具有特异性的多克隆抗血清能够检测到所有部分水解物以及两种深度乳清蛋白水解物中酪蛋白成分的残留抗原活性，其含量占总蛋白的0.05%至0.67%。在所测试的两种深度酪蛋白水解物或氨基酸基配方奶粉中均未检测到此类活性。事实证明，多克隆抗血清比单克隆抗体更适合检测水解物中的残留抗原活性。单克隆抗体针对不同酪蛋白成分上表达的表位。