Allergenene

Allergenene are substances capable of triggering allergic reactions in susceptible individuals. Most allergenes are proteins or glycoproteins that, after sensitization, are recognized by the immune system as threats. In genetically predisposed people, exposure can lead to the production of specific IgE antibodies. Upon subsequent contact, these antibodies bind to mast cells and basophils, releasing histamine and other mediators that cause symptoms.

Common allergen categories include environmental allergens such as pollen, house dust mites, mould spores, animal dander, and cockroach; food allergens such as milk, eggs, peanuts, tree nuts, soy, wheat, fish, shellfish, and sesame; and contact allergens such as nickel, latex, fragrances, and certain preservatives. Some substances can act as allergens through multiple routes, and cross-reactivity can occur between related proteins.

Symptoms caused by allergen exposure range from mild to life-threatening. Inhaled allergens often affect the nose and lungs, leading to rhinitis or asthma symptoms. Food allergens can cause oral itching, hives, vomiting, or anaphylaxis. Skin contact allergens may trigger dermatitis. The severity depends on individual sensitivity and exposure dose.

Diagnosis typically relies on medical history, skin prick tests or specific IgE blood tests, and in some cases, controlled oral food challenges. Management focuses on avoidance strategies, patient education, and action plans for potential reactions. For individuals at risk of anaphylaxis, emergency treatment with epinephrine auto-injectors is essential. Allergen immunotherapy is available for certain inhalant allergens and venom.

Regulatory labeling requirements in many regions mandate disclosure of major allergens in foods and consumer products, enabling informed choices and safer handling.