Feline allergen Fel d 7 (Fel d 7)

Feline allergen Fel d 7 is a 17.5–18 kDa protein belonging to the lipocalin family, specifically identified as a homologue of von Ebner gland protein (VEGP) [1, 4]. It is primarily secreted by the lingual salivary glands and is found in cat saliva, tears, and on the fur [1, 3]. Fel d 7 is a clinically significant cat allergen, with sensitization rates ranging from 31% to 54% among cat-allergic individuals [1, 5]. It is associated with respiratory conditions such as asthma and allergic rhinitis, as well as atopic dermatitis [1, 13]. Notably, Fel d 7 exhibits high sequence identity (approximately 63%) and structural similarity with the major dog allergen Can f 1, leading to frequent cross-reactivity between cat and dog allergies [2, 8]. In the therapeutic landscape, Fel d 7 is a target for component-resolved diagnosis and allergen-specific immunotherapy (AIT), which aims to induce immune tolerance [12, 13]. Research is also exploring the use of neutralizing monoclonal antibodies to block IgE binding and prevent allergic symptoms [12, 14]. The protein also functions as a lipid-binding molecule, carrying ligands such as palmitic and oleic acids, which may influence its allergenicity [8, 11].

Other names

von Ebner gland proteinVEGPCat lipocalinFelis domesticus allergen 7

Allergen-specific immunotherapy (AIT) induces immune tolerance through the induction of regulatory T cells (Tregs) and allergen-specific IgG4 antibodies, which compete with IgE for allergen binding.