Proteome, Allergenome, and Novel Allergens of House Dust Mite, Dermatophagoides farinae

Abstract

Dermatophagoides farinae mite is a predominant source of indoor allergens causing high incidence of allergy worldwide. People with different genetic background respond differently to the mite components, and thus the component-resolved diagnosis (CRD) is preferred to the conventional allergy test based on crude mite extract. In this study, proteome and culprit components in the D. farinae whole body extract that sensitized the allergic patients were studied by using SDS-PAGE (1DE) and 2DE-IgE immunoblotting followed by LC-MS/MS and database search for protein identification. From the 1DE, the mite extract revealed 105 proteins that could be classified into seven functionally different groups: allergens, structural components, enzymes, enzyme inhibitor, receptor proteins, transporters, and binding/regulatory/cell signaling proteins. From the 2DE, the mite extract produced 94 spots; 63 were bound by IgE in sera of 20 D. farinae allergic patients. One more protein that was not revealed by the 2DE and protein staining reacted with IgE in 2 allergic patients. Proteins in 40 spots could be identified as 35 different types. Three of them reacted to IgE of >50% of the allergic patients, and hence they are major allergens: tropomyosin or Der f 10 (75%), aconitate hydratase (70%), and one uncharacterized protein (55%). Aconitate hydratase is a novel D. farinae major allergen unraveled in this study. Several mite minor allergens that have never been previously reported are also identified. The data have clinical applications in the component-resolved diagnosis for tailor-designed allergen-specific immunotherapy.

Genomes of trombidid mites reveal novel predicted allergens and laterally-transferred genes associated with secondary metabolism

“…The major allergens in D. farinae are the 25-kDa Der f 1, a papain-like cysteine protease; and Der f 2, a 14-kDa uncharacterised protein with a ML (lipid-binding) domain [77]. However, many other minor allergens have been detected by immunoproteomic studies [113, 114] or predicted by homology searches in the D. farinae genome [77]. In L. deliense , five distinct clusters of papain-like cysteine proteases were identified (AllFam AF030), of which three were shared with D. farinae , one was shared only with D. tinctorium , and one was unique (Fig.…”

“…Recently, an alpha-enolase has been reported as a novel minor allergen in D. farinae [114]. However, the two enolases (AF031) with predicted allergenic properties in the L. deliense genome formed an orthologous cluster that was absent from other mites sequenced to date, with homologues in parasitic nematodes and distant chelicerate relatives ( e.g.…”

Mass spectrometry to complement standardization of house dust mite and other complex allergenic extracts

“…While these two HDM species cohabitate all geographical regions, one of the two species may be dominant. For example, D. pteronyssinus is most common in Australia and the United Kingdom , but D. farinae is most common in Thailand .…”

Integrating Proteomes for Lung Tissue and Lavage Reveals Pathways that Link Responses in Allergen-Challenged Mice

“…Mice exposed to allergen are a mainstay for asthma research, and a common approach is to challenge animals with inhaled house dust mite (HDM). HDM is an aeroallergen that is clinically relevant, and is a complex stimulus with multiple immunogens and stressors, including fungal spores, bacterial endotoxins, lipid-binding proteins and proteases 1,2 . Repeated HDM challenge induces pathophysiological symptoms that are hallmarks of human asthma 3 .…”