Interference of Dermatophagoides pteronyssinus sensitization in grass pollen allergy.

Summary: Background. Climate conditions in the northwest of Spain are from the rest of the country, and the pollen sensitisation rates and allergens involved are different. The present study aimed to investigate the sensitisation profile of patients with grass pollen allergy and the interference of other sensitisations in respiratory symptoms. Methods. A total of 959 Spanish patients with seasonal respiratory symptoms and a positive skin prick test (SPT) to Phleum pratense pollen were studied. Patients were classified as having rhinitis and/or bronchial asthma. A battery of SPTs, including common weeds and tree pollens, profilin, polcalcin, moulds, Dermatophagoides pteronyssinus, Lepidoglyphus destructor, and cat and dog dander were performed. Serum specific IgE (sIgE) to Phl p 1 and Phl p 5, adding sIgE to Phl p 7, Phl p 12 and house dust mites (HDMs) or other pollens in selected cases were measured. Results.The majority (89.8%) of the patients were polysensitised according to SPT. HDM co-sensitisation was the most prevalent (62.3%). Profilin and polcalcin rendered a positive result in 25.9% and 18.7% of the patients, respectively. A higher proportion of patients recognized sIgE to Phl p 1 (88.7%) with respect to Phl p 5 (59%). Phl p 1-sIgE levels were higher than Phl p 5-sIgE levels, and no differences were found in patients with rhinitis and/or asthma. However, total serum IgE was higher in patients with asthma. Multivariate regression analyses revealed that only sIgE to Dermatophagoides pteronyssinus (after adjusting by sIgE to Phl p 1, Phl p 5 and Lepidoglyphus destructor) was associated with a greater risk of asthma. Conclusions. Phl p 1 is the most relevant allergen in patients with grass pollen allergy in the northwest of Spain. Sensitisation rates against panallergens are low. Even in patients with grass pollen allergy, HDM sensitisation plays a relevant role in asthma.

Profilin, a Change in the Paradigm.

Profilin is a protein that is present in all eukaryotic cells and is responsible for cross-reactivity between pollen, latex, and plant foods. It has been classically acknowledged as a minor or nearly irrelevant allergen, although recent data are changing this conception. The objective of this manuscript is to provide a comprehensive review of published data on the role of this ubiquitous allergen in pollen, latex, and plant food allergy. The patterns of recognition of this minor allergen follow a north-south gradient. Although present in all pollens and vegetables, profilin is significantly associated with allergy to grass pollen and to Cucurbitaceae fruits. Heb v 8, the latex profilin, is usually a marker of profilin allergy in plant food-allergic patients, although it has no clinical relevance in latex allergy. Sensitization to profilin jeopardizes the diagnosis of pollen allergy and selection of immunotherapy, and although component-resolved diagnosis can identify its impact, there are no tailored treatments available. In recent years, several new publications have shown how profilin should be taken into account and, under certain circumstances, considered a marker of severity, an allergen capable of inducing respiratory symptoms, and, in its natural purified form, a potential candidate for etiological treatment of food allergy. Current data on profilin strongly support the need for a shift in the previously accepted paradigm for this allergen. More research should be done to assess the real clinical impact of sensitization in specific populations and to develop therapeutic strategies.