Egg white proteins

Egg-derived proteins, primarily sourced from the white of chicken eggs (Gallus gallus), are a group of proteins that serve as potent allergens and unintended antigens in medical products. The major allergenic components include ovomucoid (Gal d 1), ovalbumin (Gal d 2), ovotransferrin (Gal d 3), and lysozyme (Gal d 4) (Savage et al., 2016). These proteins are biologically involved in nutrient storage and antimicrobial defense within the egg, but in humans, they can trigger IgE-mediated type I hypersensitivity reactions (UniProt P01012). Clinical manifestations of exposure in sensitized individuals range from mild skin reactions to severe, systemic anaphylaxis (NIH, 2023). In the pharmaceutical industry, these proteins are significant as residual contaminants in vaccines manufactured using egg-based technologies, such as certain influenza and yellow fever vaccines (Grohskopf et al., 2023). While modern manufacturing processes have significantly reduced the concentration of these residual proteins, they still necessitate screening and precautions for highly allergic patients (CDC, 2023). There are no drugs that "target" these proteins for therapeutic inhibition; instead, treatment focuses on emergency response to exposure or desensitization through oral immunotherapy (OIT) (Burks et al., 2012). Monitoring of these antigens is typically performed using ovalbumin concentration as a surrogate marker for total egg protein content in biologics (WHO, 2022).

Other names

Egg allergensGallus gallus proteinsOvalbumin (Gal d 2)Ovomucoid (Gal d 1)Ovotransferrin (Gal d 3)Lysozyme (Gal d 4)Egg-derived antigens

The primary mechanism involves the induction of IgE-mediated type I hypersensitivity upon binding to specific IgE antibodies on mast cells and basophils; drugs like epinephrine act as physiological antagonists by stimulating alpha and beta-adrenergic receptors to reverse systemic effects, while oral immunotherapy (OIT) aims to induce desensitization and immunological tolerance through controlled, incremental exposure to the antigens (Burks et al., 2012; NIH, 2023).