Cashew allergen protein (Ana o 1, Ana o 2, Ana o 3)

Cashew allergen proteins are a group of highly stable seed storage proteins derived from the cashew tree (Anacardium occidentale) that are responsible for triggering IgE-mediated allergic reactions in sensitized individuals [8, 13, 15]. The major allergens identified are Ana o 1 (a 7S vicilin-like globulin), Ana o 2 (an 11S legumin-like globulin), and Ana o 3 (a 2S albumin) [1, 4, 6]. These proteins are characterized by their resistance to heat and proteolytic digestion, which allows them to maintain their structural integrity and allergenic potential through food processing and the human digestive tract [13, 18]. Upon ingestion, these allergens cross-link IgE antibodies on the surface of mast cells and basophils, leading to the systemic release of inflammatory mediators [13, 15]. This can result in a range of clinical manifestations, from oral allergy syndrome to severe, life-threatening anaphylaxis [8, 14, 15]. While strict dietary avoidance is the current standard of care, these proteins are the primary targets for diagnostic component-resolved testing and therapeutic strategies such as oral immunotherapy (OIT) and epicutaneous immunotherapy (EPIT) [12, 22, 23]. These therapies aim to induce immune tolerance and increase the threshold for allergic reactions by modulating T-cell responses and inducing a shift from Th2 to Th1/Treg phenotypes [10, 22]. The high potency of cashew allergens, particularly Ana o 3, makes them a significant focus for biotech companies developing food allergy treatments [1, 18].

Other names

Anacardium occidentale allergenAna o 1Ana o 2Ana o 3Cashew nut allergen

Induction of immune tolerance (desensitization) through gradual exposure to the allergen, leading to a shift from a Th2-mediated allergic response to a Th1/Treg-mediated regulatory response [10, 22, 23]. Omalizumab acts as an adjunctive therapy by neutralizing circulating IgE to prevent mast cell degranulation [12].