House dust mite and animal dander allergen extract (HDM-AD Allergen Extract)

This target represents a complex mixture of major and minor allergens derived from four distinct environmental sources: the American house dust mite (Dermatophagoides farinae), the European house dust mite (Dermatophagoides pteronyssinus), the domestic cat (Felis catus), and the domestic dog (Canis familiaris). Key molecular components include cysteine proteases (Der p 1, Der f 1), NPC2 family lipid-binding proteins (Der p 2, Der f 2), secretoglobins (Fel d 1), and lipocalins (Fel d 4, Can f 1) [3][4]. These proteins act as potent antigens that trigger Type I hypersensitivity reactions in sensitized individuals by cross-linking IgE on the surface of mast cells and basophils, leading to the release of inflammatory mediators like histamine and leukotrienes [5]. In a clinical context, these allergens are utilized as the active pharmacological agents in allergen immunotherapy (AIT), where controlled exposure aims to desensitize the patient's immune system. While they are the 'targets' of the immune system during the development of allergy, they serve as the therapeutic tool to induce long-term immunological tolerance in patients suffering from allergic rhinitis and asthma [2][6]. Because this entry combines multiple distinct species and dozens of individual protein targets into a single heading, it is classified as 'incorrect' for high-resolution molecular modeling but remains a standard grouping for clinical allergy diagnostics and treatment formulations [1].

Other names

Dermatophagoides farinae and Dermatophagoides pteronyssinus and Felis catus and Canis familiaris allergensDust mite, cat, and dog allergen mixtureEnvironmental allergen extractDer f, Der p, Fel d, and Can f allergens

Allergen immunotherapy (AIT) works by inducing peripheral T-cell tolerance, increasing the production of regulatory T cells (Tregs) and B cells, shifting the immune response from a Th2 to a Th1 profile, and stimulating the production of protective 'blocking' antibodies such as IgG4 and IgA to compete with IgE for allergen binding [1][2].