CROSS-REACTIVITY OF OLEA-EUROPAEA WITH OTHER OLEACEAE SPECIES IN ALLERGIC RHINITIS AND BRONCHIAL-ASTHMA

Cross-reactivity between pollen extracts of four species of Oleaceae w as studied: olive (Olea europaea), ash (Fraxinus excelsior), privet (L igustrum vulgare), and lilac (Syringa vulgaris). Thus, 51 patients and 13 atopic controls were studied, by means of intracutaneous skin test s, histamine-release tests against the four extracts, and specific IgE to O. europaea. The proteic content of the four extracts was assessed by SDS-PAGE and immunoblotting, and similarity of all the extracts st udied was observed after electrophoresis and immunodetection. Six comm on bands were found to be responsible for the cross-reactivity, with a pparent molecular weights of 49.6, 40, 36.7, 19.7, 16.7, and 14 kDa, r espectively. The cross-reactivity was also corroborated by immunoblott ing inhibition and FEIA inhibition. The patients had a similar respons e to the four allergenic extracts used, although the response to Olea was greatest. When the patients were compared by their geographic orig in (northern or southern Spain, according to the distribution of areas of olive pollen influence), there were no significant differences bet ween the two groups in skin reactivity, but a higher histamine release was observed for the four extracts in the southern group, although it was significant only for Fraxinus and Ligustrum. This work corroborat ed the practicality of the diagnostic methods used and the cross-react ivity between the four species studied, as demonstrated by the differe nt methods used. Therefore, we suggest that only O. europaea extract b e used in diagnosis and immunotherapy in Oleaceae pollen allergy.