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Background: Profilins are dominant pan-allergens known to cause cross-sensitization, leading to clinical symptoms such as pollen-food syndrome. This study aimed to determine the T-cell response to Phl p 12 in profilin-sensitized patients, by measuring the prevalence, strength and cross-reactivity to clinically relevant profilins., Methods: The release of Phl p allergens from pollen was determined by mass spectrometry and immunochemistry. T-cell responses, epitope mapping and cross-reactivity to profilins (Phl p 12, Ole e 2, Bet v 2 and Mal d 4) were measured in vitro using PBMCs from 26 Spanish grass-allergic donors IgE-sensitized to profilin. Cross-reactivity was addressed in vivo using 2 different mouse strains (BALB/c and C3H)., Results: Phl p 12 and Phl p 1 are released from pollen simultaneously and in similar amounts. Both T-cell response frequency (17/26 donors) and strength were comparable between Phl p 12 and Phl p 1. T-cell cross-reactivity to other profilins correlated with overall sequence homology, and 2 immunodominant epitope regions of Phl p 12 were identified. Data from mice immunized with Phl p 12 showed that cross-reactivity to Bet v 2 was mediated by conserved epitopes and further influenced by additional genetic factors, likely to be MHC II., Conclusion: The strength, prevalence and cross-reactivity of T-cell responses towards Phl p 12 are comparable to the major allergen Phl p 1, which supports the hypothesis that T cells to Phl p 12 can play an important role in development of allergic symptoms, such as those associated with pollen-food syndrome., (© 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.)

Background: Sensitisation to pan-allergens has become an interesting tool for the study of the allergenic profile of different populations. Profilins are one of the most common pan-allergens to be studied because they are responsible for a large number of sensitisations and are clearly related to cross-reactivity and co-sensitisation., Objectives: The objective of this study was to investigate the profile of sensitisation to profilins and to correlate it with sensitisation to foods and pollens., Methods: Six hundred and fifty-four consecutive patients were skin-prick tested with a battery of common allergens including pollens, epithelia, mites and moulds and profilin and divided into three groups depending on their sensitisation profile (non-atopic, atopic with pollinosis and atopic without pollinosis). Patients with symptoms were challenged and diagnosed with the offending food extracts. Profilin sensitisation was identified and analysed in detail., Results: According to the classification of the population, the prevalence of profilin sensitisation was estimated at 2.9% in patients suffering respiratory allergy, 4.2% in atopic patients, and 5.9% in pollen-sensitised individuals. Positive association was observed between pollen (except Cupressus and olive) and profilin but not with moulds, mites or epithelia. With respect to foods, positive association was only observed between profilin and melon sensitisation. Lastly, in terms of symptoms, positive association was only observed between profilin sensitisation and OAS., Conclusion: Profilin sensitisation seems to be a marker of pollen-related poly-sensitisation in our area. Pan-allergen diagnosis seems to be an essential tool for developing and improving selection of the correct treatment for allergic patients., (Copyright © 2013 SEICAP. Published by Elsevier Espana. All rights reserved.)

Background: Peach allergy is the main cause of vegetable food allergy in the Mediterranean area. Pru p 3 is the major allergen, and it is mainly found in the peel., Objective: We sought to calculate the frequency of tolerance to peach pulp in Spanish children suffering from allergic reactions after eating or having contact with peach and to analyze the sensitization pattern to peach allergens., Methods: Fifty-seven children (32 boys; median age, 7.4 yr) were included in the study. A systematized questionnaire on allergic reactions to peach was administered. Prick tests with peach peel and pulp, peach lipid transfer protein (LTP), and profilin were performed. Serum-specific IgE to peach, rPru p 1, rPru p 3, and rPru p 4 was determined by ImmunoCAP. Oral food challenges (OFCs) with peach pulp were performed on all but one child., Results: Eighty-eight percent of the children had positive prick tests with peach peel, 35% with peach pulp, 88% with peach LTP, and 9% with profilin. Serum-specific IgE to peach was demonstrated in 100% of the patients; rPru p 3-specific IgE in 96%; rPru p 1-specific IgE in 11%; and rPru p 4-specific IgE in 10%. Oral food challenge was negative in 52 (93%) children., Conclusions: More than 90% of the study population tolerated peeled peach. Pru p 3 was the major allergen. Pru p 1 and 4 showed low prevalence., (© 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.)

Background: Lipid transfer proteins (LTPs) and profilins are the most important panallergens in the management of patients who are allergic to pollen and plant food in our area. LTPs are highly stable proteins that can induce systemic symptoms after ingestion. Profilins are labile proteins that are present in pollens and vegetables. Considered markers of several types of pollen sensitization, they are responsible for cross-reactivity between pollens and vegetables. The objective of this study was to assess the frequency of sensitization to LTP and profilin using skin prick tests (SPTs) in patients referred to our allergy unit for any complaint (not only pollen and plant food allergy)., Methods: The study sample comprised 430 consecutive patients who were evaluated using their medical history and SPTs with pollen, date palm profilin, and peach extract enriched in Pru p 3 (30 g/mL) as an LTP marker., Results: We found that 52 (12.1%) patients were sensitized to profilin and 53 (12.3%) to LTP. Pollen allergy was diagnosed in 53% and plant food allergy in 11%. In the LTP-sensitized group and the profilin-sensitized group, 37.7% and 34.6% of the patients had plant food allergy, respectively. Thirty-three patients (62.3%) were sensitized to LTP but had no symptoms after eating vegetables., Conclusions: To the best of our knowledge, this is the first study to analyze the real rate of sensitization to profilin and LTP in a population sensitized to allergens other than pollens and plant foods. Twelve percent of patients were sensitized to both profilin and LTP. A large proportion of LTP-sensitized patients had no symptoms at the time of the study.

Background: Allergy diagnosis needs to be improved in patients suffering from pollen polysensitization due to the existence of possible confounding factors in this type of patients., Objective: To evaluate new diagnostic strategies by comparing skin responses to pan-allergens and conventional allergenic extracts with specific IgE (sIgE) to purified allergen molecules., Methods: One thousand three hundred and twenty-nine pollen-allergic patients were diagnosed by a combination of an in vitro method with a panel of 13 purified allergens, including major allergens and pan-allergens, using a high-capacity screening technology (ADVIA-Centaur) and skin prick test (SPT) to pan-allergens and conventional extracts., Results: There was a high concordance (kappa index) between in vitro (sIgE to major allergens) and in vivo (SPT to conventional extracts) methods in patients who were not sensitized to pan-allergens, but SPT with conventional extracts failed to diagnose patients with sensitization to pan-allergens. In patients who were simultaneously sensitized to polcalcins and profilins, there was a duplication both in the number of sensitizations to major allergens and in the years of disease evolution. There was a statistical association between sensitization to profilins and/or lipid transfer proteins and food allergy (P<0.0001)., Conclusion: The novel diagnostic strategy has proven to be a valuable tool in daily clinical practice. Introduction of routine SPT to pan-allergens is a simple and feasible way of improving diagnostic efficacy. Patients sensitized to pan-allergens should be tested by an adequate panel of allergenic molecules in order to identify the allergens that are responsible for the allergic disease.

Background: Allergy diagnosis in patients exposed to multiple pollen species is complex and misdiagnosis is often a cause for unsuccessful specific immunotherapy., Objective: We studied the sensitization profile of individual allergens (major, minor and pan-allergens) in pollen-sensitized patients in a region with high exposure to olive pollen by investigating the influence of minor allergens on allergic disease and the association between pan- and minor allergen sensitizations., Methods: A panel of 13 purified allergens, which included the most relevant allergens in the area, as well as minor olive allergens and pan-allergens, were screened using a high-capacity technology (ADVIA-Centaur) in 891 patients., Results: Olive allergy as measured by specific IgE to Ole e 1 was the leading pollinosis in the area. The minor olive allergens Ole e 7 and Ole e 9 were markers of more severe allergic illness. Profilin sensitization was associated mainly with grass allergy, the second most prevalent pollinosis. Salsola kali pollen allergy was the third most common cause of pollinosis in the area. The prevalence of sensitization to the peach allergen Pru p 3, a nonspecific lipid-transfer protein, was notable., Conclusion: Epidemiological analysis by component-resolved diagnosis is a new method, which elucidates the interaction between allergen exposure gradient and patient sensitization. High exposure leads to differential sensitization profiles some of which are associated with more severe allergic conditions. Profilin sensitization, related mainly to grass pollinosis, was a marker of more severe grass pollen sensitization.

Background: In contrast to other Rosaceae fruit, only few cases of patients with adverse reactions to strawberry are listed in literature. OBJECTIVE To identify allergenic proteins in strawberry and to express and characterize recombinant strawberry lipid transfer protein (LTP; rFra a 3)., Methods: Established apple-allergic patients were recruited on the basis of a reported allergic reaction to strawberry (n=28, confirmed by double-blind placebo-controlled food challenge in four patients) or on the basis of IgE reactivity to LTP (n=34). Sensitization to purified natural and recombinant allergens was assessed by RAST, immunoblot (inhibition) and basophil histamine release (BHR). A strawberry cDNA library was screened for genes homologous to known fruit allergens. Fra a 3 was cloned and expressed in the yeast Pichia pastoris and compared with peach and apple LTP by RAST, immunoblot-inhibition and BHR tests., Results: Genes homologous to Bet v 1, Bet v 6, profilin and LTP were identified in a strawberry cDNA library. In BHR the rFra a 3 induced histamine release at a 100-fold higher concentration than peach LTP. RAST inhibition showed high cross-reactivity to peach and apple LTP, although IgE reactivity was lower by a factor 5. On strawberry immunoblot, patients' IgE showed reactivity to a Bet v 1 homologue, profilin, LTP and high-molecular weight bands., Conclusion: In addition to a Bet v 1 homologue, strawberry also contains IgE-binding profilin and LTP. The rFra a 3 has less allergenic potency than peach and apple LTP, and therefore is an interesting tool for future immunotherapy. Fra a 3 does not seem to be clinically relevant.