Cross-reactivity between and in immunotherapy extracts for the treatment of allergy to .

and are the two most common subspecies of the genus. and have exhibited cross-reactivity in previous studies. pollen is the main cause of allergy in the Mediterranean area. It has been shown that a high percentage of patients sensitized to with allergic rhinitis (AR) have an increased risk of developing asthma. The present study aimed to confirm the cross-reactivity between and and to evaluate the use of a single extract in patients allergic to both subspecies as a preferable option for the diagnosis and treatment of allergy in a highly pollinated area of the Spanish Mediterranean coast. The present study was a single centre, observational cross-sectional study of adult patients diagnosed with AR and/or bronchial asthma who were sensitized to pollen. A total of 24 patients were enrolled in the study and included in the analysis. Allergovit immunotherapy extracts were selected for the study based on the protein content ( pollen extract). The results of an ELISA revealed that 79.1% (n=19) of the patient sera were reactive to immunotherapy extracts. ELISA inhibition assay of the IgE binding to demonstrated inhibition values >70% in the sera of highly reactive patients, confirming the cross-reactivity between the two subspecies. In addition, all patients enrolled in the study exhibited double skin positivity against and extracts, as assessed by the skin prick test, further supporting the reactivity between the two subspecies. The present study demonstrated that and pollen extracts were highly cross-reactive, and that a unique pollen extract may be used for the diagnosis and immunotherapy of patients allergic to .