Milk proteins (CMP)

Milk proteins represent a complex and heterogeneous group of bioactive molecules categorized into two primary fractions: caseins (comprising alpha-s1, alpha-s2, beta, and kappa variants) and whey proteins (including alpha-lactalbumin, beta-lactoglobulin, and lactoferrin) [5, 14]. Caseins typically associate into large colloidal micelles that serve as essential sources of amino acids, phosphate, and calcium for mammalian development [13, 14]. Whey proteins provide a broad range of physiological benefits, including potent antimicrobial, antioxidant, and immunomodulatory activities [6, 18]. Clinically, these proteins are most notable as the primary allergens in Cow's Milk Protein Allergy (CMPA), where they trigger IgE-mediated immune responses in a significant percentage of the pediatric population [2, 15]. In therapeutic contexts, milk proteins are used as antigens in oral immunotherapy (OIT) to desensitize allergic individuals by shifting the immune response from a Th2-mediated allergic state to a state of peripheral tolerance [8, 22]. Additionally, specific components such as bovine lactoferrin are under investigation for their potential to inhibit viral pathogens, including SARS-CoV-2, by interfering with viral attachment and entry into host cells [4, 12, 16].

Other names

Cow's milk proteinDairy proteinMilk allergenCasein and whey proteins

Milk proteins act as exogenous antigens in oral immunotherapy (OIT) to induce peripheral tolerance by promoting the expansion of allergen-specific regulatory T cells (Tregs) and increasing the production of blocking antibodies such as IgG4 and IgA [3, 9, 21]. Specific bioactive components like lactoferrin exhibit antimicrobial and antiviral activity by sequestering iron, binding to viral glycoproteins (e.g., SARS-CoV-2 spike protein), or blocking host cell receptors like heparan sulfate proteoglycans [4, 12, 16]. Additionally, bioactive peptides released during milk protein digestion, such as casokinins, can inhibit the angiotensin-converting enzyme (ACE), exerting antihypertensive effects [14, 20].