Characterizing Allergen Profiles and Identifying Group 2 Allergens of Three Storage Mites: Acarus siro, Chortoglyphus arcuatus and Carpoglyphus lactis.

BACKGROUND: Storage mites are important contributors to allergic diseases, yet their allergens remain poorly characterized compared to those of house dust mites. Comprehensive molecular data on storage mite allergens are limited, hindering improved diagnosis and understanding of their allergenic potential. METHODS: We assembled and annotated the genomes of three storage mite species, Acarus siro, Chortoglyphus arcuatus and Carpoglyphus lactis. Comprehensive allergen profiling was performed using integrated genomics, transcriptomics and proteomics approaches. Putative allergen genes were identified and classified into allergen groups. IgE-binding capacity of selected allergens was validated using ELISA assays. In addition, the immunostimulatory potential of newly identified allergens was assessed by measuring IL-6 production in a dendritic cell line. RESULTS: We identified 75, 70 and 64 putative allergen genes in A. siro, C. arcuatus and C. lactis, corresponding to 33, 31 and 32 allergen groups, respectively. Extensive gene family expansions and multiple isoallergens were observed, particularly, among Group 2 allergens belonging to the NPC2 family. ELISA IgE-binding assays validated four Group 2 allergens in A. siro and one in each of C. arcuatus and C. lactis. Notably, these newly identified Group 2 allergens significantly induced the production of the pro-inflammatory cytokine IL-6 in a dendritic cell line. CONCLUSION: This study provides a comprehensive genomic and proteomic characterization of storage mite allergens and identifies previously unrecognized Group 2 allergens with IgE-binding and immunostimulatory capacity. These findings establish a foundational resource for improved diagnosis of storage mite allergy and support future investigations into the molecular mechanisms underlying mite allergenicity.