Identification of B Cell Epitopes of Blo t 13 Allergen and Cross-Reactivity with Human Adipocytes and Heart Fatty Acid Binding Proteins.
Cross-reactivity between allergens and human proteins could have a clinical impact in allergic diseases. Blo t 13 is an allergen from the mite Blomia tropicalis, which belongs to the fatty acid binding protein (FABP) family and has structural homology with human FABPs. This work aimed to map B cell epitopes on Blo t 13 and to identify epitopes involved in cross-reactivity with human heart FABP (FABP3) and adipocyte FABP (FABP4). Sera from 25 patients with house dust mite (HDM) allergy that were sensitized to Blo t 13 were used for testing the reactivity of immunoglobulin E (IgE) and IgG to FABP. The epitope mapping of Blo t 13 was performed using overlapping peptides, and cross-reactivity between Blo t 13 and human FABP was analyzed using human sera and anti-Blo t 13 monoclonal antibodies. IgE antibodies to all FABPs were detected in 14/25 serum samples, and IgG was detected in 25/25 serum samples. The cross-reactivity of Blo t 13 was 42% with FABP3 and 48% with FABP4. Two IgE-binding regions were identified in Blo t 13; one between residues 54 and 72 (the main cross-reacting region) and another between residues 111 to 129. Our results suggest that exposure to the Blo t 13 allergen could induce an auto-reactive response to endogenous FABP in allergic patients sensitized to Blo t 13.
['Múnera|Marlon|M|', 'Martínez|Dalgys|D|', 'Labrada|Alexis|A|0000-0003-0956-7946', 'Caraballo|Luis|L|', 'Puerta|Leonardo|L|0000-0003-2246-9697']
D017667:Adipocytes D000485:Allergens D000595:Amino Acid Sequence D000818:Animals D000911:Antibodies, Monoclonal D003429:Cross Reactions D018604:Epitope Mapping D018985:Epitopes, B-Lymphocyte D000074026:Fatty Acid Binding Protein 3 D050556:Fatty Acid-Binding Proteins D005260:Female D006801:Humans D006967:Hypersensitivity D007073:Immunoglobulin E D007074:Immunoglobulin G D008297:Male D008925:Mites D009206:Myocardium D017434:Protein Structure, Tertiary D016415:Sequence Alignment
cross-reactivity Blomia tropicalis FABP house dust mites IgE IgG