Molecular sensitization profile to grass and olive pollens in Portugal

Background.Grass and olive pollens have overlapping pollination periods and are common allergens in the Iberian Peninsula.Objective: To determine the sensitization pattern to major Phleum pratense and Olea europaea pollens in the Portuguese population with pollen allergic rhinitis (AR) using molecular allergen diagnosis (MAD). Methods. Seasonal AR patients (≥ 12 years), with positive skin prick tests (SPT) to Phleum and Olea were recruited from 16 centers.Using ALEX 2 , specific IgE to Phl p1, Phl p2, Phl p5, Phl p6, Phl p7, Phl p 12, Ole e1, Ole e7 and Ole e9 were determined.Immunoblotting of Olea allergic patients was performed.Results.Included 175 patients (55.4% female; mean age 31.6 ± 13.3 years; 85.7% adults; 40% asthmatic, Coast 28%/Inland 72% and North 29.1%/Centre 20.6%/South 50.3%).Considering Phleum MAD, 85.7% were sensitized to Phl p1, 45.7% to Phl p2, 50.3% to Phl p5, 45.7%, to Phl p6, 10.9% to Phl p7 and 22.9% to Phl p12.Sensitization to Ole e1 was found in 56.6%, to Ole e7 in 1.7% and Ole e9 in 3.4% M a n u s c r i p t a c c e p t e d f o r p u b l i c a t i o npatients.Sensitization to Phl p7 was more frequent in asthmatics (17.4% vs 6.6%; p = 0.044).Sensitization to Phl p5, Phl p6, Phl p12 and Ole e1 was more frequent in inland.Regarding sensitization patterns: 53.1% patients were sensitized to both species genuine´ sIgE, 38.3% to Phleum and 3.4% only to Olea species' sIgE.Immunoblotting of Olea allergic patients showed a high intensity band that may correspond to Ole e12.Conclusions.MAD showed "genuine" Grass and Olea sensitization in approximately 50% of our patients.