Reactivity of Rat and Man to Egg-White

The hen’s egg is a rich source of dietary protein and as such is important in human nutrition. Unfortunately, the white of an egg is not tolerated by some individuals and its ingestion causes unpleasant symptoms of an allergic nature. The clinical problem of egg-hypersensitivity is complex, especially as many of the protein fractions of egg-white may cause an allergic response in sensitive individuals. Nevertheless, the unusual reaction of the rat to egg-white in many ways resembles the different allergic manifestations produced by egg in man. For instance, in both species egg-white may cause urticaria, angioedema, and signs of shock, these symptoms being of an anaphylactoid or anaphylactic origin. Furthermore, genetical factors are important in determining egg-white reactivity in both man and the rat. Experimental investigations into the basic mechanisms involved in the reaction of rats to egg-white might reveal new and more effective treatments against egg-white allergy in man. This article reviews some biological aspects of egg-white which are relevant to this problem.