Pru P3 Research Articles

Artificial intelligence tools for molecular analysis of sensitization profiles in patients with atopic dermatitis and bronchial asthma

Background. The variety of characteristics that should be taken into account in the clinical phenotyping of allergic diseases is currently being discussed. One of such characteristics is the individual spectrum of sensitization. An important stage in modern allergology has become the introduction of molecules / components for the detection of mediated reactions to specific class E immunoglobulins.Aim. To determine the dominant phenotypes of sensitization in patients with severe atopic dermatitis and bronchial asthma based on the results of molecular diagnostics by the ImmunoCAP Immuno Solid-phase Allergen Chip (ISAC) method using machine learning.Materials and methods. The study included 100 patients who were candidates for genetically engineered biological therapy (n = 63), severe atopic dermatitis (n = 20), or their combination (n = 17) were included. Allergodiagnosis was performed by the ImmunoCAP ISAC method.Results. Based on the results of the study, 6 phenotypes were identified. In phenotype 1, pollen molecules (Amb a1, Phl p4) and crossed reactive food molecules (Mal d1, Ara h8, Gly m4, Act d8, Pru p3) are the leading, among epidermal molecules only Fel d1 (epidermal allergen) and Asp f6 (fungal allergen) are found. For phenotype 2, the significant allergens were fungal (Asp f6), epidermal (Can f1, Can f5, Can f6, Fel d1), food (Gad c1) and cross reactive food molecules (Mal d1, Pru p1. Ara h8, Cor a1.0401). In phenotype 4, only 3 allergen groups are present:epidermal (Fel d1, Fel d2, Can f5, Can f6, Can f3), fungal (Asp f6), and cross food allergy (Jug r3, Pru p3). Phenotype 5 and 6 are dominated by epidermal molecules (Can f1 and Fel d1), true food allergies allergens (Gad c1 and Gal d1 and Gad c1, Gal d1, Gal d3, respectively). In phenotype 3, a combination of the previously labeled molecules is noted.Conclusion. Each of the identified phenotypes reveals a different set of molecules that can be used in real clinical practice to develop reduced panels, making them more accessible.

Impact of pollen exposure and age distribution on diagnostic tests for safe introduction of various nuts in patients with a primary nut allergy

Introduction ( contexte de la recherche ) The performance of nuts skin prick-test (SPT) and specific IgE is known to potentially be altered by the cross-reactivity with pollens. This can result in misguidance for safe introduction of nuts in patients allergic to one or multiple nuts. We sought to evaluate the impact of pollen sensitization related to the patients age and his geographical area under the nuts diagnostic tests performance in patients with a primary nut allergy. We analyzed paraclinical data from a prospective multicenter pan-European study (the Pronuts study) including SPT and specific IgE (whole extract and major allergens) for nuts, sesame seed and pollens (Bet v 1 and Pru p 3) from allergic patients with a primary nut allergy. To analyze the performance of the tests, we made ROC curves using these variables. One hundred and twenty children were enrolled. Sensitization to Bet v 1 and PR-10 nuts components (Ara h 8 and Cor a 1) were more prevalent and significantly higher in Geneva and London than in Spain, whereas sensitization to Pru p 3 and LTP nuts components (Ara h 9, Cor a 8, Jug r 3) were more prevalent and had higher specific IgE levels in Spain. Specific IgE to PR-10s and LTP nuts components were significantly higher in older patients (≥ 6 years) than in younger children. Levels of specific IgE to nuts seed storage proteins tended to be higher in patients ≥ 6 years compared to younger children. Concerning the performance of the diagnostic tests, in children older than 6 years, specific IgE to Ara h 2 performed significantly better than peanut SPT. Similarly, the AUC for SPT to hazelnut was larger in younger children. However, specific IgE to Cor a 9 and Cor a 14 performed better than hazelnut SPT in children older than 6 years of age in Geneva and London, respectively. For cashew and walnut, no clear differences were found between the AUC for SPT, IgE or components based on age categories. For safe introduction of various nuts in patients diagnosed with a primary nut allergy, the diagnostic strategy needs to be adapted to the local pollen exposure, especially in older children, as sensitization to Bet v1 or Pru p3 may lead to false positive IgE or SPT results to various nuts.

Evaluation of two commercial peach extracts for skin prick testing in the diagnosis of hypersensitivity to lipid transfer protein. A multicenter study.

The clinical usefulness of two commercial peach extracts for SPT (by Lofarma SpA and ALK-Abellò, respectively) was compared in a multicenter study carried out in Italy. Peach allergic patients were tested with the two extracts in parallel and underwent the detection of IgE specific for all three peach allergens currently available (Pru p1, Pru p3, and Pru p4, respectively). The two extracts were almost identical in terms of sensitivity and specificity, being able to detect virtually all patients sensitized to stable peach allergens (lipid transfer protein (LTP) and, presumably, peamaclein) but scoring negative in patients exclusively sensitive to labile allergens (either PR-10 and/or profilin). Thus, the two extracts represent an excellent tool to carry out a preliminary component-resolved diagnosis of peach allergy at the first patient visit.

Pru p3 sublingual immunotherapy and allergy to lipid transfer protein, a case report

Pru p3 sublingual immunotherapy and allergy to lipid transfer protein, a case report

Characterization of Peanut Allergic Patients in an Area with a High Ltp Prevalence

We studied the pattern of sensitization to relevant allergens of peanut (Ara h2 and Ara h9) and peach (Pru p3) in a peanut allergic patients in an area with strong prevalence of LTP sensitization. Subjects with a clear history of reaction after peanut ingestion and peanut-specific IgE were included (N=170). Specific IgE (sIgE) to peanut and peach , allergens Ara h2, 9 and Pru p3 were measured by ImmunoCAP. The subjects were grouped in intervals of 15 years: Group A) 15-30 y.o. (N=64); Group B) 31-45 y.o. (N=80) and Group C) more than 45 y.o. (N=26). The clinical symptoms reported were: anaphylaxis in 60% of the cases, urticaria/angioedema in 35% and OAS in 6%. Skin prick test (SPT) and sIgE to peanut were positive in 48% and 61% of the subjects, respectively. We observed that in Group A this percentage was higher than in other groups, being 60% and 72% for SPT and sIgE to peanut, respectively. sIgE to Ara h9 and Pru p3 were both positive in 80% in Group A, 56% and 63% in Group B; and 17% and 21% respectively in Group C. No recognition was detected to Ara h 2. A 65% of the patients were also allergic to peach. We detected that in these patients the percentage of positive cases to Pru p3 was slightly higher than Ara h9, but not significant. Peanut allergy in Mediterranean adult population is due to the LTP, Ara h9. A significant decrease of positive skin test and sIgE along age was detected.

FOOD SENSITIZATION IN CHILDREN WITH OPISTHORCHIS FELINEUS INVASION

Aim: to determine the mechanism of food sensitization in children with chronic Opisthorchis felineus invasion. Patients and methods: during the epidemiological study the groups of patients (7–10 years) with chronic opisthorchiasis (n =237) and children without chronic opisthorchiasis (n =496) were formed. The investigation included interviewing of parents / guardians, measurement of total IgE, specific IgE to food allergens and component-resolved diagnostic, real-time PCR in stool samples. Results: the chronic opisthorchiasis invasion in children is associated with reduced risk of food sensitization, compared with non-infected group (9,7 vs 16,94%, OR =0,53; 95% CI 0,31–0,88; p =0,01). Opisthorchiasis of high intensity negatively correlated with increased level of specific IgE to food allergens in serum (OR =0,46; 95% CI 0,24–0,91; p =0,023). The association between level of total IgE and intensity of opisthorchiasis combinated with food sensitization was found. The sensitization to allergens class I (cyp c1, cor a11, gal d2, pru p3) is more prevalent in patients with opisthorchiasis, in uninfected children the sensitization to bet v1-homologues (mal d1, pru p1, cor a1, ara h8) is most common. Conclusions: the epidemiological data on the effect of the Opisthorchis felineus invasion on mechanisms of food sensitization in children were obtained.

Anaphylaxis caused by flaxseed

Methods and results Prick-prick carried out with flaxseed showed a strong positivity. Skin prick test to inhaled allergens were positive to mites, dog and cat danders, plain tree and grasses. Skin prick test to food allergens were positive to almond, hazelnut, peanut, chestnut, walnut, mustard, lentils, soybeans, rice, oat, corn and lupine. Total IgE was: 291 UI/ml. Specific IgE (CAP, ThermoFisher Scientific) to flaxseed was 2.68 kU peach 7.65 kU/L, peanut 2.01 kU / L , lettuce 0.92 kU / L , lupin 3.76 kU / L. Corn IgE 2.71 kU / L , Pru p3 7.62 kU / L , Cor a8 0.68 kU / L. ISAC, ImmunoCAP was positive to Fel d1, Phl p1, Der f1, Der f2, Der p1, Der p2, Pla a3, Ara h9, Cor a8, Jug r3, Pru p3 and Art v3. ISAC performed after inhibit patients’s serum (ISAC inhibition) with a complete flaxseed extract (f233:Linum usitatissium from ImmunoCAP, ThermoFisher Scientific) did not reduced the positivity to non-specific lipid transfer proteins (nsLTP). ISAC inhibition with a complete mite extract (d1: D. pteronyssinus from ImmunoCAP, ThermoFisher Scientific) reduces exclusively the signal of mites (Der f1, Der f2, Der p1, Der p2) in >83%.An immunoblot performed with flaxseed extracts (soluble and liposoluble), showed the presence of an IgE-binding band of about 18 kDa in the liposoluble fraction and a 20 kDa band in the soluble one.

Immunological changes after one year of specific immunotherapy with Pru p 3

Rationale In Southern Europe Pru p3 is the primary sensitizer of plants fruit and responsible for severe reactions. Specific immunotherapy (SIT) brings a new perspective to treat anaphylactic patients. There is a lack of knowledge regarding immunological response that includes changes in the basophil activation and antibody production during IT. We aimed to analyse early changes in the basophil response to Pru p 3 and another related allergen (Ara h 9) during the first year of sublingual immunotherapy (SLIT).

Basophils response to Pru p 3 and Ara h 9 in patients sensitised to peach under specific immunotherapy

Rationale In Southern Europe Pru p3 is the primary sensitizer of plants fruit and it is responsible of severe reactions. Specific immunotherapy (SIT) brings a new perspective to treat those patients. There is a lack of knowledge regarding cellular responses that include changes in the basophil activation during the IT. We aim to analyse early changes in the basophil response to Pru p 3 and other related allergen (Ara h 9) after the first month of sublingual immunotherapy (SLIT).

Food sensitization in children with Opisthorchis felineus invasion

To determine the mechanism of food sensitization in children with chronic Opisthorchis felineus invasion. During the epidemiological study the groups of patients (7-10 years) with chronic opisthorchiasis (n = 237) and children without chronic opisthorchiasis (n = 496) were formed. The investigation included interviewing of parents/guardians, measurement of total IgE, specific IgE to food allergens and component-resolved diagnostic, real-time PCR in stool samples. The chronic opisthorchiasis invasion in children is associated with reduced risk of food sensitization, compared with non-infected group (9.7 vs 16.94%, OR = 0.53; 95% CI 0.31-0.88; p = 0.01). Opisthorchiasis of high intensity negatively correlated with increased level of specific IgE to food allergens in serum (OR = 0.46; 95% CI 0.24-0.91; p = 0.023). The association between level of total IgE and intensity of opisthorchiasis combinated with food sensitization was found. The sensitization to allergens class I (cyp c1, cor a11, gal d2, pru p3) is more prevalent in patients with opisthorchiasis, in uninfected children the sensitization to bet v1-homologues (mal d1, pru p1, cor a1, ara h8) is most common. The epidemiological data on the effect of the Opisthorchis felineus invasion on mechanisms of food sensitization in children were obtained.

Modification du spectre de l’allergie aux protéines de transfert lipidique par les anti-inflammatoires non-stéroïdiens

The major allergens of rosaceae are pathogenesis related proteins that are secreted to protect the plant against phytopathogenic fungus. Pru p3, a lipid transfer protein (LTP) is one of peach major allergens. A 38 year-old woman had a history of isolated peach allergy since the childhood (contact urticaria). Consumption of peeled peaches and other rosaceae was well tolerated. She occasionally took non-steroidal anti-inflammatory drugs (NSAIDs) on demand for migraine. She presented anaphylactic symptoms three hours after nectarine consumption. She had taken ketoprofen before meal. Positive skin prick tests were observed for peach, nectarine, plum and cherry. Specific IgE to Pru p3 were positive, specific IgE for other peach allergens remained negative. Challenge test with nectarine alone and NSAID alone were negative. We hypothesized that intake of NSAID before fruit eating may have increased the level of LTP allergen in the serum, leading to clinical manifestations. A similar mechanism has already been described in food anaphylaxis due to wheat with previous NSAID intake.

In vivo and in vitro studies on the sensitisation to a panel of allergens in a large rosacea allergic group of patients

Allergy to peach and apple is a frequent problem in the Mediterranean area. Both fruits share allergens between them and with those from other plants and pollens. Component resolved diagnosis assays (CRD) enable to detect IgE antibodies to a wide panel of allergens. A detailed clinical evaluation plus CRD permit a precise analysis of sensitizations to many allergens. Our aim was to analyse sensitisation to fruit and pollen allergens by in vivo/in vitro methods in patients allergic to peach and/or apple. Methods We included 107 patients. A detailed history, including questions related with response or tolerance to different fruits and plants, skin prick test (SPT) with a large panel of representative allergens in our area, and specific IgE antibodies using a CRD platform (ISAC, Phadia). Results Sixty-six cases (61,68%) had symptoms with peel peach, 46(42,99%) with pulp peach and 21(19,62%) with apple. SPT with Pru p3 was positive in 53(49,53%), to Pru p1 in 9(8,41%) and to Mal d1 in 38(35,51%). CRD was positive to Pru p3 in 45(42,05%) and to Mal d1 in 6(5,6%). From the total group, 27(25,23%) tolerated peel peach, 47(43,92%) pulp peach and 76(71,02%) apple. Patients had skin test and CRD positive to allergens from fruits that they tolerated. Furthermore, different degree of clinical response and sensitization was obtained with all the other allergens evaluated. Conclusions In vivo and in vitro evaluations with an extensive panel of allergens enable to make a precise diagnosis of allergic patients to fruits. However, discrepancies exist between clinical response and sensitization. Further studies are in progress for understanding these findings.

Rhinitis induced to mace

Results Skin prick test to mace and ginger (10%) were positive and specific IgE to Pru p3 and mace were detected. Double-blind, placebocontrolled, oral food challenge (DBPCFC) with this spice showed rhinitis in few minutes and was negative to ginger. Through electrophoresis of peach, Pru p3, mace and ginger extracts were identified and the corresponding proteins purified and characterized as allergens. Mace extract was recognized by both anti-Pru p3 and antiTLPs antibodies, however immunoblotting study with patient sample demostrated proteins bands immunodetection in this extract with similar molecular weight to peach thaumatins. Finally skin prick tests with these purified allergens (Pru p 2.1 y 2.2) were positive. Conclusion Thaumatin-like proteins are a new family of pollen and fruit allergens. Because of the sequence homologies between PR-5 proteins and thaumatin, an intensely sweet tasting protein isolated from the fruits of the West African rain forest shrub Thaumatococcus daniellii, these molecules are referred to as thaumatin-like proteins (TLP’s). To our knowledge, this is the first report on the implication of TLPÂ s in spice allergy. Unfortunately, information on fundamental aspects of the TLP family remains quite limited, this means that challenging fundamental and applied studies need to be conducted to characterize TLP’s significance and clinical involvement.

Peach allergy: different clinical profiles across Europe

Rosaceae fruit allergy is the most common food allergy in Europe in patients over 5 years of age. The two fruits most frequently involved are peach and apple. Different clinical phenotypes of peach allergy are observed across Europe in relation to different allergen sensitisation patterns to the peach allergens Pru p1 (Bet v 1 homologue), Pru p 3 (peach lipid transfer protein, LTP), and Pru p 4 (peach profilin). In areas rich in birch trees of Central and Northern Europe peach allergy is linked to birch pollinosis and apple allergy, and the major allergen involved is Pru p 1. These patients present mild oropharyngeal symptoms (oral allergy syndrome, OAS) upon peach ingestion. Profilin co-sensitisation is also found in a minority of patients, but the clinical presentation is similarly OAS. In contrast, in the Mediterranean areas free of birch trees peach allergy may result from a primary sensitisation to Pru p 3, or be linked to pollen allergy with sensitisation to pollen profilin and secondary to Pru p 4, or a combination of both. In patients monosensitised to Pru p 3 the phenotype is severe and the great majority experience systemic reactions including anaphylaxis. In subjects monosensitised to Pru p 4, peach allergy is linked to a pollen allergy, generally to grass pollen, and the phenotype is mild with OAS in all the patients. When sensitisation to Pru p 3 and Pru p 4 are combined systemic reactions are less frequently observed than in patients monosensitised to Pru p3, and OAS is more frequently reported. Sensitisation to Pru p 2, the thaumatin like protein in peach, may be found in combination with Pru p 3 and 4, but its clinical relevance has not yet been established. Peach allergy across Europe is an interesting model food allergy that illustrates how different allergen sensitisation profiles determine the clinical phenotypes of fruit allergy. The reason for the (almost) lack of sensitisation to Pru p 3 in Central and Northern Europe still remains unclear.

In Vitro Evidence Of The Synergistic Effect Of Non Steroidal Anti Inflammatory Drugs (NSAIDs) Into Ig-E Mediated Food Allergy Response In Basophils

RATIONALE: It has been reported that NSAIDs can increase the severity or induce some food allergies. The aim of this study is to evaluate the effect in basophiIs of NSAIDs in IgE mediated allergic responses to peach lipid transfer protein (Pru p3). METHODS: 24 patients with peach allergy according to clinical history, positive skin prick test (SPT) and serum specific IgE to Pru p3 > 0.75 kU/L were selected (Group A). Exacerbation or induction of the peach allergy symptoms after NSAIDs intake was reported in all patients tolerant to NSAIDs. 7 peach allergic patients with no exacerbation of symptoms by NSAIDs intake, positive SPT and serum specific IgE to Pru p3 > 0.75 kU/L (Group B), and 5 healthy subjects (Group C) were also included. Basophils response was evaluated through CD63 expression using the Flow2CAST (Bühlmann) kit. Stimuli were performed with Pru p 3 and L-ASA at different concentrations. RESULTS: In Group A a statistically significant increase in basophil activation when stimulation was performed with Pru p 3 together with L-ASA (3mM, 0.3mM and 0.1mM) compared to the activation induced by Pru p 3 alone (Wilcoxon Matched Pairs test: 3mM, p<0.0001; 0.3mM, p=0.0117 and 0.1mM p=0.0085). This increase was not observed in Group B. In Group C the basophil activation test with Pru P 3 and L-ASA did not show any response. CONCLUSIONS: We report preliminary results of an in vitro model showing that NSAIDs affect somehow on basophil IgE-mediated responses in some patients with Pru p 3 allergy.

モモ果皮からのモモアレルゲンＰｒｕ ｐ３抽出

（1） 少量のモモ果皮から主要アレルゲンPru p3を抽出する方法として，高速振盪機を使用した抽出方法を検討した．5gの果皮を20mmol/Lのアスコルビン酸ナトリウムを含有するpH 5のクエン酸-リン酸緩衝液10ml中で10分間振盪をおこなうと，夾雑物の影響が少ない状態でタンパク質が抽出され，N末端アミノ酸解析に十分なPru p3が得られた．（2） モモ果皮からmRNAを取得することを目的に，全RNAの抽出をSDS-フェノール法で行った．その後キットを用いてmRNAを精製したところ，5gの試料から抽出した場合は8.75μgのmRNAが得られることがわかった．mRNAからcDNAを合成し，cDNAを鋳型にしたRT-PCRにより，Pru p3の遺伝子発現が確認した．

Specific sublingual immunotherapy with peach LTP (Pru p 3). One year treatment: a case report

AbstractIntroductionFood allergy is an increasing problem with limited therapeutic approaches apart from to the eviction diet.Case presentationA 40-year-old female patient with food allergy symptoms was polysensitized to almost all vegetable food since the age of 36; the onset of symptoms was during pregnancy. The allergological study demonstrated positive skin prick tests (SPT) to nuts, legumes, cereals, spices, several fresh fruits including peach, and other groups of vegetable foods however, it was negative to common aeroallergens. Serum specific IgE levels were negative (&lt;0.35 kU/L) to profilin and carbohydrate determinants, but positive to Pru p 3 (3.5 kU/L). Positive double-blind placebo-controlled food challenge to peach confirmed the allergic disease. She received specific sublingual immunotherapy with native Pru p 3 at a concentration of 40 μg/ml with 5 administrations per week and a cumulative dose of 200 μg of nPru p 3 per month. After an ultra-rush build-up phase concluded in one day she continued therapy during a year with 5 administrations per week. The clinical evolution and laboratory studies demonstrated an early reduction on SPT reactions with no relevant changes on serum specific IgE, IgG, IgG1and IgG4to Pru p 3 during the immunotherapy period. The challenge test was negative 4 months after the beginning of the SLIT. Regarding clinical response she markedly improved after the first month of treatment, and by the 3th month she had no major vegetable dietary restrictions, except for nuts and pepper.ConclusionThese results demonstrate the excellent efficacy and safety of sublingual specific protein immunotherapy developed according to the patient specific sensitivity profile to Pru p3.

Specific sublingual immunotherapy with peach LTP (Pru p 3). One year treatment: a case report.

IntroductionFood allergy is an increasing problem with limited therapeutic approaches apart from to the eviction diet.Case presentationA 40-year-old female patient with food allergy symptoms was polysensitized to almost all vegetable food since the age of 36; the onset of symptoms was during pregnancy. The allergological study demonstrated positive skin prick tests (SPT) to nuts, legumes, cereals, spices, several fresh fruits including peach, and other groups of vegetable foods however, it was negative to common aeroallergens. Serum specific IgE levels were negative (<0.35 kU/L) to profilin and carbohydrate determinants, but positive to Pru p 3 (3.5 kU/L). Positive double-blind placebo-controlled food challenge to peach confirmed the allergic disease. She received specific sublingual immunotherapy with native Pru p 3 at a concentration of 40 μg/ml with 5 administrations per week and a cumulative dose of 200 μg of nPru p 3 per month. After an ultra-rush build-up phase concluded in one day she continued therapy during a year with 5 administrations per week. The clinical evolution and laboratory studies demonstrated an early reduction on SPT reactions with no relevant changes on serum specific IgE, IgG, IgG1 and IgG4 to Pru p 3 during the immunotherapy period. The challenge test was negative 4 months after the beginning of the SLIT. Regarding clinical response she markedly improved after the first month of treatment, and by the 3th month she had no major vegetable dietary restrictions, except for nuts and pepper.ConclusionThese results demonstrate the excellent efficacy and safety of sublingual specific protein immunotherapy developed according to the patient specific sensitivity profile to Pru p3.

Crystal Structure of Peach Pru p 3, the Prototypic Member of the Family of Plant Non-specific Lipid Transfer Protein Pan-allergens

This study describes the three-dimensional crystal structure of a non-specific lipid transport protein (ns-LTP) from Rosaceae. Whilst ns-LTPs from species other than Rosaceae, such as nuts, cereals, grape, oranges and vegetables are also responsible for plant food allergies, this is less frequent compared with ns-LTPs from Rosaceae in the Mediterranean area. In this heterologously expressed peach Pru p3, a ligand is present inside the central cavity of the protein, presumably a fatty acid that was present or produced in the culture medium of the expression organism Escherichia coli. Moreover, the two molecules of ns-LTP present in the asymmetric unit bind this ligand in a different way, suggesting a significant degree of plasticity for the peach ns-LTP binding cavity, despite the presence of four disulphide bridges. Two molecules are present in the asymmetric unit: molecule A is a fully liganded protein, while molecule B apparently represents a partially liganded state. Also, molecular dynamics simulation, along with other evidence, suggests that these two molecular conformations represent different states in solution. Comparison of the 3D models of different ns-LTPs justifies the evidence of a high degree of conservation of the putative IgE binding epitopes among proteins of the Rosaceae family and the presence of significant amino acid replacements in correspondence of the same regions in ns-LTPs of botanical species unrelated to Rosaceae.

Presence of Allergenic Proteins in Different Peach (Prunus persica) Cultivars and Dependence of Their Content on Fruit Ripening

It has been reported that various cultivars of fruits and vegetables may present a different pattern for the contained allergens. Here, we report on the different content in allergenic proteins for different peach (Prunus persica) cultivars, sampled during two consecutive harvest seasons. Fruits from six cultivars of peaches were harvested fully ripe, and the proteins extracted from whole or chemically peeled fruits were analyzed by SDS-PAGE and immunoblotting. All the protein extracts from whole fruit contained a 9 kDa protein. This protein proved to be absent in the extracts taken from chemically peeled fruit. In four cultivars, this protein corresponds to the allergen Pru p3, a lipid transfer protein that causes the oral allergy syndrome (OAS) in sensitized people. In the following year, fruits from four of the six cultivars of peaches studied previously were harvested at different times, at one and two weeks before the commercial ripening time and when fully ripe, to ascertain whether the presence of the 9 kDa allergen might be related to the ripening process. Two cultivars out of four produced an intense allergenic band corresponding to a 9 kDa protein already two weeks before the commercial ripening date, while the others showed a progressive increment of the 9 kDa allergen during ripening.