Perfil de reatividade de IgE, IgG4 e IgG1 ao extrato alergênico de Dermatophagoides farinae em indivíduos atópicos e não atópicos por meio de imunoproteômica

Abstract

Dermatophagoides farinae (Df) is considered one of the major house dust mite and it is an important source of indoor allergens worldwide. Several Df allergens occur as isoallergens that present changes in amino acid sequences or glycosylation, leading to differences in allergen sensitization. The aim of this study was investigate the reactivity of IgE, IgG1 and IgG4 antibodies to Df antigenic isoforms in Brazilian atopic and non-atopic subjects, with potential application for the allergy laboratorial diagnosis and follow-up of specific allergen immunotherapy. Atopic (n=60) and non-atopic (n=30) subjects were selected on the basis of the respiratory allergy history and skin prick test (SPT) to house dust mite allergens. Sera were analyzed by enzyme-linked immunosorbent assay (ELISA) for measuring levels of IgE, IgG1 and IgG4 antibodies to Df allergen. Crude Df extract was separated by one (1-D)- and two (2-D)-dimensional electrophoresis with subsequent 1-D and 2-D immunoblot for evaluating the profile of IgE-, IgG1-, and IgG4-binding components from the Df allergen extract in sera from atopics and non-atopics. Levels of IgE, IgG1 and IgG4 specific to Df and frequencies of 1-D reactivity profile were used to select sera to immunoproteomic analyses. 2-D IgE, IgG1 and IgG4 reactivity profile shown interestingly patterns of recognition and some spots could be related to hypothetical allergens. Single IgE and double IgE/IgG4 binding in atopic migrated only below 37 kDa and single IgG1 binding migrated exclusively above 37 kDa. The immunoproteomics approach in both atopic and non-atopic groups showed a great number of antigenic components and the most of them could be related to a known hypothetical allergen. In addition, the immunoreactivity of these proteins observed may be potentially useful for serodiagnosis and opens further opportunities for the development of a personalized immunotherapeuticalcomposition for treating patients with allergic disease.