Allergenic contribution of the IgE-reactive domains of the 1,3-beta-glucanase Ole e 9: diagnostic value in olive pollen allergy.
BACKGROUND
Designing of methods for an accurate diagnosis is a main goal of allergy research. Olive pollen allergy is currently diagnosed using commercially available pollen extracts that do not allow identification of the molecules that elicit the disease.


OBJECTIVE
To analyze the suitability of using the N- and C-terminal domains (NtD and CtD, respectively) of the 1,3-beta-glucanase Ole e 9, a major allergen from olive pollen, for in vitro diagnosis.


METHODS
Serum samples from 55 olive-allergic patients were assayed using enzyme-linked immunosorbent assay to study hypersensitive patients with IgE reactivity to Ole e 9. The specific IgEs to NtD and CtD, obtained by recombinant technology, were determined by means of immunoblotting, enzyme-linked immunosorbent assay, and inhibition assays.


RESULTS
Thirty-one of 33 serum samples from Ole e 9-allergic patients were IgE reactive to recombinant NtD (rNtD) (n = 26 [79%]), recombinant CtD (rCtD) (n = 22 [67%]), or both (n = 17 [52%]). Nine patients (27%) were exclusively reactive to rNtD and 5 (15%) to rCtD. Inhibition assays of IgE binding to Ole e 9 with a mixture of both domains abolished 90% of the binding, whereas 44% and 45% were abolished when rNtD and rCtD were used, respectively.


CONCLUSIONS
Because sensitization to NtD or CtD of Ole e 9 could be correlated to vegetable food-latex-pollen cross-reactivity processes or to the exacerbation and persistence of asthma, respectively, these molecules could be used in vitro as markers of disease to classify patients and to design a patient-tailored immunotherapy approach.
Palomares
Oscar
O
Departamento de Bioquímica y Biología Molecular, Facultad de Química, Universidad Complutense de Madrid, Madrid, Spain.
Villalba
Mayte
M
Quiralte
Joaquín
J
Rodríguez
Rosalía
R
D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D000937:Antigen-Antibody Reactions; D052179:Antigens, Plant; D001249:Asthma / Q000175:diagnosis* / Q000209:etiology / Q000276:immunology; D001667:Binding, Competitive; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D031658:Olea / Q000276:immunology*; D010446:Peptide Fragments / Q000276:immunology; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D011058:Pollen / Q000009:adverse effects* / Q000276:immunology; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000175:diagnosis* / Q000209:etiology / Q000276:immunology; D012882:Skin Tests; D001617:beta-Glucosidase / Q000737:chemistry / Q000235:genetics / Q000276:immunology*
D000485:Allergens; D052179:Antigens, Plant; D010446:Peptide Fragments; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D007073:Immunoglobulin E; C433244:OLE9 protein, Olea europaea; D001617:beta-Glucosidase