Can Physicochemical Properties Alter the Potency of Aeroallergens? Part 1 - Aeroallergen Protein Families

Abstract

Purpose of review: Respiratory allergies are non-communicable diseases caused by the hypersensitivity of the immune system to environmental aeroallergens. The culprits are aero-transported proteins eliciting respiratory symptoms in sensitized/allergic individuals. This review intends to provide a holistic overview on the categorization of aeroallergens into protein families (Part 1) and to exploit the impact of physicochemical properties on inhalant protein allergenicity (Part 2). This first part will focus particularly on aeroallergen organization into families and how this classification fits their physicochemical properties.

Recent findings: Aeroallergen classification into protein families facilitates the identification of common physicochemical properties, thus aiding a better comprehension of known allergens, while predicting the behavior of novel ones. The available online databases gathering important features of aeroallergens are currently scarce. Information on distinct aeroallergen classification is still lacking, as data is dispersed and often outdated, hampering an efficient evaluation of new aeroallergens.

Keywords: Aeroallergens; Allergic asthma; Allergic sinusitis; Inhalant allergies; Physicochemical properties; Protein allergenicity; Respiratory allergies.

Fig. 1

Pymol representation of: a) Crystal structure of polcalcin allergen Che a 3 from Chenopodium album with calcium ions represented as green spheres (PDB ID: 2OPO); b) 3D structure of troponin C allergen Bla g 6 from Blattella germanica predicted by AlphaFold; c) 3D structure of myosin light chain allergen Bla g 8 from Blattella germanica predicted by AlphaFold; d) 3D structure of sarcoplasmic calcium binding allergen Aed a 5 from Aedes aegypdi predicted by AlphaFold; e) Crystal structure of profilin allergen Bet v 2 from Betula pendula (PDB ID: 5NZC); f) Crystal structure of lipocalin allergen Bla g 4 from Blattella germanica (PDB ID: 4N7C); g) Crystal structure of FABP allergen Der f 13 from Dermatophagoides farina (PDB ID: 2A0A); h) Crystal structure of nsLTP allergen Art v 3 from Artemisia vulgaris (PDB ID: 6FRR); i) 3D structure of α -amylase allergen Der p 4 from Dermatophagoides pteronyssinus predicted by AlphaFold; j) 3D structure of subtilisin-like protease allergen Cur l 4 from Cochliobolus lunatus predicted by AlphaFold; k) Crystal structure of β -expansin/Grass group-1 allergen Zea m 1 from Zea mays (PDB ID: 2HCZ); l) Crystal structure of Ole e 1-like allergen Lig v 1 from Ligustrum vulgare (PDB ID: 6YOA); m) Crystal structure of PR-10 allergen Bet v 1 from Betula pendula (PDB ID: 1BV1); n) 3D structure of tropomyosin allergen Der p 10 from Dermatophagoides pteronyssinus predicted by AlphaFold). All protein structures are represented in cartoon and colored by chain