Beta-lactoglobulin A (BLG)

Beta-lactoglobulin A is the primary whey protein found in the milk of cows and other ruminants, belonging to the lipocalin family of transport proteins (UniProt: P02754). It is characterized by an eight-stranded, anti-parallel beta-barrel structure that forms a central hydrophobic pocket, which allows it to bind and transport small hydrophobic molecules such as retinol and fatty acids (PubMed: 10998255). While it serves as a major source of amino acids for the neonate, it is absent in human milk, making it a potent foreign antigen in humans. Consequently, Beta-lactoglobulin A (clinically known as Bos d 5) is a major allergen responsible for cow's milk protein allergy (CMPA), particularly in infants and young children (Allergome: Bos d 5). It is not a traditional therapeutic target for drug inhibition; instead, it is utilized in diagnostic assays and as the active component in oral immunotherapy (OIT) protocols designed to induce desensitization and clinical tolerance in allergic patients (PubMed: 28641963). Additionally, its robust structure makes it a subject of research for the encapsulation and delivery of hydrophobic nutraceuticals.

Other names

Bos d 5LGBBeta-LGWhey protein variant A

Induction of immune tolerance through allergen-specific immunotherapy (desensitization), which shifts the immune response from a Th2-mediated allergic profile to a Treg and Th1-mediated tolerant profile, often characterized by increased allergen-specific IgG4.