Comprehensive Allergen Profile of Blomia tropicalis Provides Insights into the Component-Resolved Diagnosis of Mite Allergy

Abstract

BackgroundBlomia (B.) tropicalis, as an important species of house dust mites (HDMs), plays a critical role in allergic diseases in tropical populations, but its allergen components are less investigated than those of other HDMs. Multiple omics methods have largely improved the identification of mite allergens. Here, we sought to identify a comprehensive allergen profile of B. tropicalis and advance the allergen component-resolved diagnosis (CRD) of mite allergy. MethodsReference mite allergen sequences were searched in a high-quality genome of B. tropicalis. Comparative analysis was performed for important allergen groups. ELISA was used to assess the allergenicities of recombinant proteins of specific allergens. ResultsA complete allergen profile of B. tropicalis was revealed, including thirty-seven allergen groups (up to Blo t 42). In-depth comparative analysis not only determined the homology of major allergen groups 5 and 21 but also shed light on the emergence and divergence of chitin-binding allergens. The specific Blo t 12 was identified to be a chitin-binding protein originating from the chitinase of allergen group 15. Immunoassays of recombinant proteins verified three novel allergens and the ELISA results suggested geographical differences in the B. tropicalis sensitization rate. ConclusionsThe comprehensive allergen profile revealed in B. tropicalis, the comparative analysis of allergen groups and the immunoassay assessment of recombinant proteins largely expanded our knowledge to B. tropicalis allergens and could ultimately benefit the CRD of HDM allergy.