Currant allergy and the Rosaceae-grass pollen allergy syndrome: a case report.

BACKGROUND: Despite the increasing use of currants in culinary recipes, currant allergy has rarely been reported. OBJECTIVES: To study a case of currant allergy and to explore cross-reactivity between grass pollen and Rosaceae family fruit allergens. METHODS: Skin prick tests to pollen and skin prick-to-prick tests with currants and peach were performed. Specific IgE levels were determined using the CAP method. We prepared a protein extract of 0.1 mg/mL in phosphate-buffered saline using red currant in the presence of protease inhibitors. Immunoblot inhibition studies were performed to explore cross-reactivity between grass pollen and currant allergens. RESULTS: Skin prick test results were positive to Dactylis, arizonic, and olive pollens. Results of skin prick-to-prick tests with fresh red and black currants were negative and positive, respectively, to peach. The specific IgE level was 5.7 KU/L to red currant and 2.92 KU/L to peach (CAP). Western blot analysis with red currant extract revealed specific IgE protein bands of 37 and 26 kDa. Preincubation of sera with extracts from red currant and peach inhibited both IgE bands, and preincubation with Dactylis pollen inhibited the 37-kDa band only. CONCLUSIONS: We report a case of allergy to grass pollen with an oral allergy syndrome involving several fruits from 2 different families of the Rosidae subclass confirmed by in vitro tests. Inhibition studies demonstrated cross-reactivity between different fruits (currant and raspberry) from the Rosidae subclass and were incomplete with grass pollen allergens.     

Lack of crossreaction with Bet v 1 in patients sensitized to Dau c 1, a carrot allergen.

BACKGROUND: Pollen-related food allergies to fresh fruit and vegetables are a well-known clinical phenomenon. Allergens related to Bet v 1 are responsible for these cross-reactions. OBJECTIVE: To characterize the allergen recognized by four carrot-allergic patients. METHODS: Sera from four patients showing strong immediate systemic reactions after contact or ingestion of raw carrot were studied by immunoblotting. The 18-kD allergen, named Dau c 1, was isolated by ethanol precipitation and specific extraction after SDS-PAGE and its N-terminal amino acid sequence was determined. RESULTS: All the patients had significant levels of specific IgE to carrot, but no specific IgE to birch pollen was detected in any of them. IgE immunodetection with the sera only recognized a single band of around 18 kD in raw carrot and in celery (with weaker reaction). No reactive band was found with birch pollen. These results were confirmed using a polyclonal anti-carrot antiserum. The carrot IgE-binding protein had a pl of 4.2 and its N-terminal sequence was homologous to that of Bet v 1 and to allergens previously described in celery and other foods. The four patients studied were not sensitized to birch pollen and three of them tolerated fruit ingestion. CONCLUSION: The whole study indicated that a sensitization to Dau c 1 induces IgE antibodies that do not cross-react with birch pollen allergens.     

Carrot allergy: double-blinded, placebo-controlled food challenge and identification of allergens

BACKGROUND: Allergic reactions to carrot affect up to 25% of food-allergic subjects. Clinical manifestations of carrot allergy and IgE responses to carrot proteins, however, have never been studied in subjects with carrot allergy confirmed by means of double-blinded, placebo-controlled food challenge (DBPCFC). OBJECTIVE: The purposes of this investigation were to confirm clinically relevant sensitizations to carrot by means of DBPCFC, to validate current diagnostic methods, and to identify IgE-reactive carrot proteins in patients with true allergy. METHODS: DBPCFCs were performed in 26 subjects with histories of allergic reactions to carrot. Patients underwent skin prick tests with carrot extract, fresh carrot, and various pollen extracts. Specific IgE to carrot, celery, birch, and mugwort pollen and to rBet v 1, rBet v 2, and rBet v 6 were measured through use of the CAP method. Carrot allergens were identified by means of immunoblotting and blotting inhibition. RESULTS: Twenty of 26 patients had positive DBPCFC results. The sensitivity of the determination of carrot-specific IgE antibodies through use of the CAP method (> or =0.7 kU/L) was 90%, the sensitivity for skin prick testing with commercial extracts was 26%, and the sensitivity for prick-to-prick tests with raw carrot was 100%. The Bet v 1--related major carrot allergen Dau c 1 was recognized by IgE from 85% of patients; 45% were sensitized to cross-reactive carbohydrate determinants and 20% to carrot profilin. In 1 subject, a Bet v 6--related carrot allergen was recognized. In 4 patients, IgE binding to Dau c 1 was not inhibited or was weakly inhibited by rBet v 1 or birch pollen extract. CONCLUSION: This study confirmed the allergenicity of carrot by means of DBPCFC. DBPCFC-positive patients had exclusively specific IgE antibodies to birch pollen--related carrot allergens, Dau c 1 being the major allergen. The lack of inhibition of IgE binding to Dau c 1 by birch allergens in a subgroup of patients might indicate an secondary immune response to new epitopes on the food allergen that are not cross-reactive with Bet v 1.     

IgE to food allergens are highly prevalent in patients allergic to pollens, with and without symptoms of food allergy

Serum samples from 274 patients allergic to one or more of three pollens (birch, grass, mugwort), from 36 patients allergic to cat and/or Dermatophagoides pteronyssinus but not to pollen and from 55 non-allergic controls, as well as 20 cord blood samples, were examined for specific IgE to six ‘pollen-associated’ food allergens In uiing a new sensitive assay (CAP). A questionnaire asking for reactions to food was also sent to all patients. In the pollen group, 111 patients (47%) were positive (≥0.71 kU/l) fora food allergen (392 positive tests). Of these, 92 were sensitive to apple, 68 to potato, 64 to carrot, 63 to celery, 61 to peach and 44 to melon. In the non-allergic group, no IgE to any of the food allergens tested was found, whereas in the group allergic to non-pollen allergens, only one individual had such an IgE. The CAP assay was found to he more sensitive than RAST for the allergens studied. A history of clinical reactions (oral symptoms in 67, rhinoconjunctivitis in 65, asthma in 42 and urticaria in 39) to the corresponding food allergen was reported mainly by patients with positive CAP. In conclusion, we found a high prevalence of IgE to some food allergens in patients allergic to pollen and Ihe absence of such antibodies in the control groups. The new in vitro assay, being moresensitue than previous ones, indicated a high prevalence of food specific IgE in pollen allergic patients, which in many cases did not correspond to clinical symptoms of food allergy.     

Fruit-pollen-latex cross-reactivity: implication of profilin (Bet v 2).

BACKGROUND: An association between allergy to fruits and latex, and between pollen and plant-derived food has been described. The cross-reactive structures responsible for these associations have not yet been completely elucidated. METHODS: IgE reactivity to the recombinant allergens Bet v 1 and Bet v 2, different pollens, natural latex, papain, and bromelain was investigated in 29 patients with allergy to fruits or vegetables who lived in an area without birch trees. RESULTS: Exactly 79.3% of patients were allergic to grass pollen, and two of them had clinical allergy to latex. Serum IgE reactivity (CAP) to birch pollen was found in 65% of patients, to Bet v 2 in 51.7%, to Bet v 1 in 3.4%, to latex in 58.6%, to bromelain in 51.7%, and to papain in 17.2% of patients. All subjects with positive IgE to Bet v 2 had also reactivity to latex, grass, olive tree, birch, and mugwort pollens. The six patients not allergic to pollen did not show IgE reactivity to latex, Bet v 1, or Bet v 2. A significant correlation was found between CAP to latex with Bet v 2 (r=0.86, P<0.001), with birch (r=0.86, P<0.001), and with ryegrass (r=0.81, P<0.001). Immunoblotting using nine sera with positive CAP to birch pollen showed IgE-binding to a 15-kDa band that was recognized by antiprofilin monoclonal antibody. Bet v 2 CAP could be inhibited up to 52% by ryegrass and up to 23% by mugwort. CAP to latex was almost completely inhibited by ryegrass pollen with sera from five subjects without symptoms due to latex, whereas no inhibition was observed with serum from one patient with allergy to latex. CONCLUSIONS: Patients with allergy to plant-derived food and associated pollinosis showed a high frequency of IgE reactivity to Bet v 2, which may cause positive serum IgE determinations to latex and birch pollen due to the presence of cross-reactive epitopes. IgE reactivity to Bet v 2 may serve as an indicator of broad sensitization.     

Celery allergens in patients with positive double-blind placebo-controlled food challenge

BACKGROUND: Recently, for the first time, allergy to celery was confirmed by double-blind placebo-controlled food challenge (DBPCFC). Api g 1, Api g 4, cross-reactive carbohydrate determinants (CCD), and a 60 kDa allergen have been described as celery allergens. OBJECTIVE: To get insights in IgE responses of patients with a positive DBPCFC to celery tuber (celeriac) compared with patients with a negative challenge test. METHODS: Specific IgE to native and heated celery tuber and to recombinant Api g 1, the major celery allergen, were determined by enzyme allergosorbent test and immunoblotting. IgE binding to Api g 1, Api g 4, and CCD was confirmed by inhibition experiments that used recombinant Api g 1, recombinant Api g 4, pure N-glycans, and extracts of celeriac, lychee fruit, and pollens of birch, mugwort, and timothy grass as inhibitors. RESULTS: Immunoblotting with sera from 22 patients with a positive DBPCFC to celeriac confirmed the presence of known allergenic structures: The major allergen Api g 1 (16 kDa) was recognized by IgE from 13 of 22 patients (59%). Another major allergen was CCD, determined by IgE reactivity in 12 of 22 patients (55%). Celery profilin, Api g 4, was recognized by IgE from 5 of 22 patients (23%). CONCLUSION: Our DBPCFC-positive patients exclusively presented IgE to known celery allergens, although the prevalences were slightly different than were previously reported. No obvious differences were found in patients with positive IgE antibody but negative challenge test. IgE binding to all 3 structures in celeriac extract was inhibited by birch pollen extract, whereas mugwort pollen extract could only inhibit IgE reactivity to Api g 4 and CCD. Inhibition experiments with a purified carbohydrate moiety clearly showed that the IgE epitope mannose-xylose-fucose-glycan (Manalpha1-6[Xylbeta1-2]Manbeta1-4GlcNAcbeta1-4[ Fucalpha1-3]GlcNAc) or a closely related structure is present in celeriac extract and is important in patients with clinical allergy to celery.     

Celery allergy associated with birch and mugwort pollinosis

Skin prick tests (SPT) with various celery, carrot and potato preparations (raw, cooked, cooking water of each vegetable and allergen extracts) as well as specific IgE determinations by RAST to celery mix, celeriac (or root celery), stick celery and heated celery extracts were performed in 70 patients with positive prick or intracutaneous tests to birch and/or mugwort pollens and celery (extract and/or raw). 94% of the patients showed positive prick tests to raw celeriac, 36% to cooked celeriac and 8/13 to cooking water. Celery-birch positive patients (n = 13) showed negative or low RASTs to heated celery extracts and to stick celery. By contrast, in the celery-mugwort sensitive patients (n = 6) the celery RASTs with heated celery extracts remained clearly positive and high RAST values to stick celery could be found. Celery-birch-mugwort-association (n = 22) favoured more positive results with relatively high values of RAST to celeriac. The results of homologous and heterologous RAST inhibition experiments with birch, mugwort, unheated and heated celery (100 degrees C) carried out in nine celery-RAST positive sera are also discussed.     

Anaphylactic reaction to young garlic

BACKGROUND: Garlic is well known to cause contact dermatitis and asthma. However, it is a very rare cause of food allergy. We present the case of a 23-year-old woman with previous history of allergy to pollen and dried fruit, and food-dependent, exercise-induced anaphylaxis for which no specific food could be identified as responsible, who experienced an anaphylactic reaction after eating young garlic. METHODS: Skin prick tests and specific IgE immunoassay with several pollens and foods were performed, as well as the prick-prick test with young garlic and SDS-PAGE followed by immunoblotting IgE to young garlic and other Liliaceae species, mustard, sesame, parsley, celery, hazelnut, almond, and pollen of birch and mugwort. RESULTS: Skin prick tests and specific IgE were mainly positive for grass, plane tree, and mugwort pollen; peanut; hazelnut; walnut; almond; and mustard. Prick-prick tests with young garlic and garlic were positive. Total IgE was 113 U/ml. SDS-PAGE immunoblotting showed IgE-binding bands at 12 kDa to young garlic, garlic, onion, and leek extracts. Similar bands could also be detected with mugwort pollen and hazelnut extract. CONCLUSIONS: We describe IgE-mediated reaction to young garlic in a patient sensitized to pollen and dried fruit.     

Assessment of cross-reactivity in patients allergic to birch pollen by immunoblotting

Cross-reactivity related to birch pollynosis and ingestion of certain food poses a severe clinical and diagnostic problem. Sera were taken from 21 adult patients allergic to birch pollen with symptoms after ingestion of apples, carrots and celeries, and seven control subjects allergic to birch pollen only. Concentrations of allergen-specific IgE against allergens of birch pollen, apple, carrot and celery were measured with enzyme immunoassay, fluorimetric enzyme-linked immunoassay and immunoblotting. Immunoblotting technique may serve as a valuable diagnostic tool for birch pollen associated cross-reactivity.     

Olive (Olea europea) and privet (Ligustrum vulgare) pollen allergens. Identification and cross-reactivity with grass pollen proteins.

Protein blotting studies showed that three olive pollen components with mol. wts approximately 18-19, 20 and 40 kD can be considered to be major allergens. For privet pollen, the highest recognition frequencies were for allergens of mol. wts approximately 20, approximately 19, approximately 40 and approximately 70 kD. When results with the 62 subjects examined were separated into groups corresponding to their geographical locations, viz. Italy, France and Australia, subjects sensitized to olive, but not other pollens (some Italian subjects), were found to show higher frequencies of recognition of major olive allergens than subjects sensitized to olive pollen via cross-reacting allergens from unrelated pollen sources (the Australian and French subjects). Blotting, adsorption and elution and inhibition studies clearly demonstrated allergenic cross-reactivity (that is, antigenic cross-reactivity detected by IgE antibodies) between olive, privet, ryegrass (Lolium perenne) and couch grass (Bermuda grass: Cynodon dactylon) pollen components. As with our previous findings with birch pollen, we conclude that the presence of pollen-reactive IgE antibodies may not necessarily be a true reflection of the sensitizing pollen species.     

Allergenic cross-reactivity of olive pollen

BACKGROUND: Sera of patients allergic to olive (Olea europaea) pollen were used to analyze the IgE cross-reactivity between olive-pollen extract and other pollens obtained from phylogenetically unrelated species. METHODS: We used IgE immunostaining of pollen extracts blotted to nitrocellulose membranes after SDS-PAGE and inhibition analysis of this binding. RESULTS: A high inhibition of the IgE binding on olive-pollen extract was exhibited by birch, mugwort, pine, and cypress pollens, suggesting that these extracts contain proteins which share common epitopes and thus can be recognized by olive-allergic sera. IgE binding to Gramineae pollen extracts was not inhibited by olive-pollen extract, indicating a primary sensitization of the patients to these species. From the inhibition assays, the presence of an allergen of 45 kDa in the olive pollen, which has no homologous counterparts in other allergenic species, has been inferred. CONCLUSIONS: Olive pollen contains allergens which cross-react with pollens from unrelated species, a fact that could simplify the diagnosis and treatment of pollinosis.     

IgE immune response to Ginkgo biloba pollen.

BACKGROUND: The ginkgo (Ginkgo biloba L.) continues to be planted as a shade tree in preference to other species in Seoul, Korea. The proportion of ginkgo to total shade trees was 43.2% in 1998, but the allergenic characteristics of ginkgo pollen has not been elucidated. OBJECTIVES: This study was undertaken to obtain information regarding the skin reactivity rate to ginkgo pollen in a population of Korean subjects with respiratory allergy. Possible ginkgo pollen allergens and the cross-reactivity of ginkgo pollen with other prevalent pollens were also examined. METHODS: Four hundred and forty-seven patients with asthma and/or allergic rhinitis were skin prick tested with extract of ginkgo pollen (1:20 wt/vol). Of these patients, positive skin responders (A/H ratio > or =2+) were selected for ELISA and immunoblot experiments. RESULTS: A total of 21 patients (4.7%) showed skin reactivity (A/H ratio > or =2+) to ginkgo pollen in the skin prick test. They were also cosensitized to many other tree, grass, and weed pollens. Sixteen (76%) of the 21 positive skin responders showed specific IgE responses to ginkgo pollen in ELISA. In inhibitory ELISA, IgE binding to ginkgo pollen was inhibited by more than 80% by oak, ryegrass, mugwort, and ragweed; and 34% by hop Japanese; and 10% by rBet v 2 at 10 microg/mL. In immunoblot, 10 out of 21 sera (48%) reacted to the 15-kD protein of ginkgo pollen, 9 (43%) to 33-35 kD, and 8 (38%) to 36-38 kD. In inhibitory immunoblot, IgE binding to ginkgo pollen proteins was almost completely inhibited by oak, ryegrass, mugwort and ragweed, but only partially by hop Japanese and rBet v 2. CONCLUSION: The skin reactivity rate to ginkgo pollen is approximately 4.7% in a population of Korean subjects with respiratory allergy. Since ginkgo pollen has a high cross-reactivity with other prevalent pollens, it could cause clinical symptoms during its pollen season by cross-reacting with the IgE produced in response to other pollens in patients sensitized to multiple pollens.     

Clinical and immunologic reactivity of patients allergic to grass pollens and to multiple pollen species. I. Clinical and immunologic characteristics

The heterogeneity of pollen-allergic individuals is well-known but poorly characterized. Twenty-six patients were studied to characterize their immunologic and clinical patterns. Thirteen patients were allergic only to grass pollens, and 13 other patients were allergic to grass-pollen and other pollen species, including Cupressaceae, plane tree, olive, and Parietaria. The IgE response was assessed by the titration of serum total IgE and orchard grass-specific IgE, as well as by IgE immunoblots to orchard-grass pollens. Clinical reactivity was assessed by nasal challenge with orchard-grass pollens before the pollen season and nasal and bronchial symptom-medication scores between April 1 and June 15. Pollen counts were obtained during this period of survey. Polysensitized patients had significantly increased levels of serum total and specific IgE and a greater heterogeneity of IgE immunoblots, suggesting an enhanced qualitative and quantitative IgE immune response. Polysensitized patients had nasal and bronchial symptoms occurring earlier than grass pollen-allergic individuals, confirming the priming effect caused by other plans flowering with an earlier season for both nasal and bronchial mucosa. Alternatively, the early symptoms may be attributable to the tree pollens or might reflect the higher grass-pollen IgE level in the polysensitized group. Bronchial symptoms appeared a few weeks after nasal symptoms. Nasal challenges were similar in both groups, and the severity of nasal symptoms during the season was not significantly different in both groups, suggesting that the intensity of symptoms is not related to the sensitization nor to the IgE immune response of the subjects.     

A study of allergens in celery with cross-sensitivity to mugwort and birch pollens

Sixty-one sera with positive RAST to mugwort pollen ( Artemisiae vulgaris ) were submitted to RASTs for birch pollen ( Betula verrucosa) and celery ( Apium graveolens ). In 36 cases RAST results were positive for celery. In addition, 23 sera presented specific IgE to birch pollen. The binding of specific IgE to individual allergens in celery, mugwort pollen and birch pollen was studied by the immunoblotting technique. This involved electrophoretic separation of allergenic extracts, electrotransfer of proteins onto nitrocellulose sheets and sensitive immunoenzymatic detection. Eighteen sera had specific IgE binding to two celery components of molecular weight around 15 kD. All these sera also detected a 15 kD allergen in mugwort and two allergens in birch of 14 kD and 16 kD molecular weight. The sera that did not detect the 15 kD bands in celery failed to react with both the 15 kD mugwort component and the 14 and 16 kD birch components. Specific cross-inhibitions of the detection of these allergens on immunoblots were obtained by pre-incubation of the sera with crude extract of the three species. These results strongly suggest that such allergens display some structural identity and that they could be at the origin of some cases of crossed hypersensitivity to celery, mugwort pollen and birch pollen.     

Identification of a 36‐kDa olive‐pollen allergen by in vitro and in vivo studies

BACKGROUND: Ole e 1 has been considered the major allergen of olive (Olea europaea) pollen. Some other relevant allergens (Ole e 2, 3, 4, and 6) have been recently described. This work aimed to study the IgE-binding frequency of a 36-kDa protein from O. europaea pollen in a large population of olive-allergic patients, its allergenic reactivity in vivo, and its presence in olive pollens of different origin, as well as in other relevant allergenic pollens. METHODS: Identification of IgE-binding components from O. europaea pollen extracts was elucidated by inhibition of SDS-PAGE immunoblotting using recombinant profilin (Ole e 2) and Ole e 1 molecules. The IgE-binding frequency of the 36-kDa protein was estimated by Western blot in a sample of 120 sera from olive-allergic patients. The cutaneous test with the 36-kDa protein was performed by intradermoreaction in allergic patients and control subjects. RESULTS: Exactly 83% of the sera from O. europaea-allergic patients recognized a protein with an apparent molecular weight of 36 kDa, under reducing conditions. It was detected by sera from monosensitized and polysensitized patients, showing a higher IgE frequency than the major allergen Ole e 1 (59%) and the minor profilin (Ole e 2) allergen (27%). Similar reactivity rates (79%) was found by intradermal test. Extracts from olive pollens collected in California presented a much higher amount (around 16-fold on average) of the 36-kDa protein than those from pollens of Spanish origin. The presence of similar allergens was detected only in closely related species (Syringa, Fraxinus, Ligustrum), and not in other common allergenic pollens. CONCLUSIONS: The 36-kDa protein constitutes a major allergen for olive-sensitized patients, but it is not equally represented in O. europaea pollens of different origins.     

Allergenicity and cross-reactivity of pine pollen

Background Pine pollen has long been considered a non-allergenic pollen. The large size of the grain and its low levels of proteins are the main reasons invoked to explain this low allergenicity. The aim of this study was to describe the main allergenic bands of Pinus radiata ( PR ) and its cross-reactivity with other pine species, other conifers and grass pollen.
Methods Sixty-five pine-pollen-allergic patients (51% also sensitized to grass pollen) were studied. Skin prick tests (SPT) to a battery of allergens including PR, Pinus pinea, Pinus sylvestris, Pinus nigra and Cupressus sempervirens pollens and specific IgE determination to PR and Pinus strobus were performed. IgE-immunoblotting to a PR extract and other pine pollens was also carried out. UniCAP inhibition and immunoblotting inhibition studies were performed to assess the cross-reactivity between different pollens.
Results The SPTs were positive with all the pine pollen extracts tested in 69% of the patients. Specific IgE was positive to PR or P. strobus in 77% of the patients, and to Lolium perenne in 51%. Nine different allergenic bands were detected. The two main allergens were a 42 kDa band recognized by 85% of the patients and a band of approximately 6–8 kDa recognized by 40%. A high degree of cross-reactivity was observed between different pine pollen species, but not between pines and C. sempervirens pollen. A partial cross-reactivity could be seen between pine and grass pollens only in patients also sensitized to L. perenne .
Conclusions Pine pollen should be considered as a potential allergenic pollen especially where this pollen is abundant. The detection of a high number of patients that were monosensitized to pine pollen suggests the possibility of treating these patients with specific immunotherapy.     

Cypress pollen allergy. Identification of allergens and crossreactivity between divergent species

Abstract. Studies employing sera from 34 subjects allergic to while cypress pine ( Callitris glaucophvlla ) pollen identified 18 IgE antibody-binding components in the pollen of this species, five of which (MWs∼94, 68, 64, 43 and 34 kDa) were recognized by all of the sera. Protein blotting and quantitative inhibition studies revealed clear cross-reactivity between C. glaucophylla and Cupressus sempervirens pollen proteins and striking similarities in the IgE recognition band patterns of the two pollens. Inhibition experiments with other pollen extracts revealed that sera from C. glaucophylla pollen-allergic subjects can be divided into two groups – those inhibited only by extracts from the two Cupressaceae pollens and those inhibited both by these pollen proteins and by pollen extracts from other species. Most of the crossreactions in the latter group cannot be explained on the basis of taxonomic relationships or separate sensitizations. As with previous studies on birch and olive pollens, we conclude that pollen allergenic crossreactivity is much more wide-ranging than generally believed.     

Celery allergy: clinical and biological study of 20 cases

In 20 patients, the ingestion of celery was responsible for mucocutaneous symptoms (generalized urticaria and angioedema) (18/20) and respiratory disorders (7/20). Four cases of systemic anaphylaxis were observed. The main associated allergic disorder was pollinosis (16/20). Food allergy to other vegetable products, mainly other Umbelliferae and apples, coexisted with celery allergy in 12 cases. It was found that celery allergy is mediated by IgE antibodies: it is easily diagnosed by skin tests (fresh extracts of celery may be used) and by adequate RAST (17 positive results). Cosensitization with mugwort pollen (14 cases) and birch pollen (9 cases) was found. Celery allergens responsible for clinical sensitization originate chiefly in the tuber and are at least partly thermally labile. The frequent association with pollen sensitization suggests the existence of common antigenic epitopes in celery extracts and mugwort and birch pollens. The immunologic investigations carried out so far (RAST inhibition and immunoprint) seem to support this hypothesis.     

A clinical study of two cases with immediate hypersensitivity to apple-pulp and an investigation of cross-allergenicity between apple-pulp allergen and some other pollen allergens

In Japan there are no case reports of immediate hypersensitivity to apple-pulp. Here, we report on two patients: a 23-year-old woman and a 14-year-old girl with 3-year and 7-year histories, respectively, of anaphylactic reactions to apple-pulp. In the first patient, eating raw apples immediately elicited itching and tingling of the lips and mouth with severe edema of the lips and tongue, irritation of the throat and slight colic in the upper abdomen. In the second, nausea and vomiting occurred after ingestion of apples. In skin prick tests, they showed positive reactions to apple-pulp extract prepared by the method of Bj?rkstén et al. and to fresh apple juice. In addition, IgE antibody to the apple-pulp extract was detected in the sera of both patients. They also possessed IgE antibodies to some other species of both pollens and fruits/vegetables in their sera. In the present study, cross-allergenicity between apple-pulp and five pollen species, which consisted of birch, Japanese cedar, orchard grass, mugwort and ragweed pollen, was investigated by RAST inhibition. The apple-pulp extract effectively inhibited RASTs to all the pollens except Japanese cedar pollen. These results suggested that the four pollens might have shared allergen with the apple-pulp extract.     

Immunological Investigation of Possible Structural Similarities between Pollen Antigens and Antigens in Apple, Carrot and Celery Tuber

Crossed line immunoelectrophoresis (CLIE) was used to show that a minor allergen present in birch pollen and another present in timothy pollen shared common epitopes with antigens in apple, carrot and celery tuber. Major pollen allergens were not involved. Structural similarities were also noticed in some mugwort pollen antigens and antigens in apple, carrot and celery, but none of these mugwort antigens acted as an allergen. In crossed immunoelectrophoresis (CIE) of samples of apple, carrot or celery extracts towards antibodies against birch pollen, grass pollen or mugwort pollen, four to 14 distinct precipitates were observed and shown to be specific. In crossed radioimmunoelectrophoresis (CRIE) none of the precipitates could be shown to act as an allergen. Using allergen detection on nitrocellulose paper, the apple, carrot and celery extracts were shown to possess IgE-binding capacity.