Food allergy and the potential allergenicity-antigenicity of microparticulated egg and cow's milk proteins

Approximately 3-4 million Americans experience food allergic reactions at some time in their lives. In the pediatric population, eggs and milk are most frequently implicated in food allergic reactions. The most well-understood adverse reactions to foods are secondary to the development of IgE antibodies to specific food antigens. Once an individual becomes sensitized (i.e., makes specific IgE antibodies), ingestion of the food may lead to a variety of cutaneous, respiratory, and/or gastrointestinal symptoms, and anaphylactic shock. The use of SDS-PAGE and immunoblot analyses with sera from documented food allergic patients provide a very sensitive indicator of the antigenic/allergic composition of various foods. As demonstrated in a study of infant formulas of hydrolyzed cow's milk protein, the absence of demonstrable bands on SDS-PAGE gels and immunoblots correlates with an inability to provoke an allergic response. In addition, it was demonstrated that SDS-PAGE with silver staining could detect protein fractions at a concentration of 50-100 ng/ml, a concentration below which allergic individuals are unlikely to react. These studies confirmed that patients clinically allergic to egg and/or cow's milk possess IgE and IgG antibodies to protein fractions in egg and cow's milk, as well as the microparticulated egg/cow's milk proteins, Simplesse and Beta IL. Compared to egg and cow's milk, there is no evidence that the Simplesse or Beta IL test materials possess any "novel" protein fractions or antigens. In addition, there is no evidence that these microparticulated proteins result in increased immunologic activity, as determined by the intensity of protein band staining.(ABSTRACT TRUNCATED AT 250 WORDS)