Les Euphorbiacées

[1] - Gadermaier G, Dedic A, Obermeyer G, Frank S, Himly M, Ferreira F. Biology of weed pollen allergens. Curr Allergy Asthma Rep 2004;4:391-400

Weeds represent a heterogeneous group of plants, usually defined by no commercial or aesthetic value. Important allergenic weeds belong to the plant families Asteraceae, Amaranthaceae, Urticaceae, Euphorbiaceae, and Plantaginaceae. Major allergens from ragweed, mugwort, feverfew, pellitory, goosefoot, Russian thistle, plantain, and Mercurialis pollen have been characterized to varying degrees. Four major families of proteins seem to be the major cause of allergic reactions to weed pollen: the ragweed Amb a 1 family of pectate lyases; the defensin-like Art v 1 family from mugwort, feverfew, and probably also from sunflower; the Ole e 1-like allergens Pla l 1 from plantain and Che a 1 from goosefoot; and the nonspecific lipid transfer proteins Par j 1 and Par j 2 from pellitory. As described for other pollens, weed pollen also contains the panallergens profilin and calcium-binding proteins, which are responsible for extensive cross-reactivity among pollen-sensitized patients.

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[2] - Singh BP, Verma J, Sridhara S, Rai D, Makhija N, Gaur SN, et al. Immunobiochemical characterization of Putranjiva roxburghii pollen extract and cross-reactivity with Ricinus communis. Int Arch Allergy Immunol 1997;114:251-257

Putranjiva roxburghii (PR) pollen has been found to be an important aeroallergen for type I hypersensitivity. In the present study, the IgE binding proteins of PR pollen have been characterized and compared with pollen allergens of Ricinus communis (RC) belonging to family Euphorbiaceae. On isoelectric focusing, PR pollen extract resolved into 35 bands (pI 3-9), whereas SDS-PAGE separated it into 18 protein components (MW 14-100 kD). Pooled patient's sera (ID +ve to PR) recognized 12 allergenic proteins in Putranjiva and five of them (MWs 92, 80, 55, 43 and 30 kD) showed immunologic reactivity to most of the sera samples tested individually by immunoblot. A number of shared allergenic proteins (MWs 92, 80, 66, 50, 43 and 14 kD) were observed between PR and RC pollen extracts on immunoblot using Putranjiva allergic serum pool. Inhibition in the binding for most of PR pollen allergenic proteins was obtained with higher concentration of RC extract than PR itself, depicting the presence of cross-reacting allergens in both. Putranjiva pollen extract was fractionated by a combination of DEAE Sephadex-A 50 and Sephadex-G 200 column chromatography. Periodate deglycosylation of western blotted PR extract and Put I fraction indicated the involvement of carbohydrate moieties in the allergenic activity. Of the two fractions from Put I (Ia and Ib), Put Ib was found to be the most allergenic protein by ELISA inhibition. Dot blot analysis with individual patients sera identified it as a major allergen of PR.

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[3] - Rawat A, Singh A, Roy I, Kumar L, Gaur SN, Ravindran P, et al. Assessment of allergenicity to Mallotus phillipensis pollen in atopic patients in India: a new allergen. J Investig Allergol Clin Immunol 2004;14:198-207

OBJECTIVE: Pollen grains of the Euphorbiaceae family are well known causative agents of respiratory allergies in India, European countries and USA. Mallotus phillipensis belongs to the same family and may have some common allergenic properties. It has thus been evaluated for the first time in Indian population for its pollinosis causing properties. METHODS: Pollen antigen of Mallotus phillipensis (MP) was extracted and characterized for its protein components by biochemical methods. Pollinosis potency of crude extract of MP pollen was evaluated by skin prick test on population residing in different parts of India. Specific IgE binding characteristics of the extract were determined by ELISA and Immunoblot. RESULTS: Marked skin reactivity in 5.7% atopic population was recorded and subjects constituting 23.8% of the total patients tested showed skin sensitivity to the MP pollen antigen. Significantly raised specific IgE against MP pollen were recorded in 50% of the skin test positive patients. A number of protein bands were detected in a wide Molecular weight range as well as in acidic pI range, by SDS-PAGE and IEF, respectively. A total 11 protein fractions were detected by the specific IgE antibodies on immunoblotting with patient's sera and were considered allergenic. CONCLUSION: Patients from different geographical regions have shown sensitization to MP pollen antigen. Many proteins have similar molecular weights and pI as other allergenic members of the family (Ricinus communis and Putranjiva roxburghii) found in India, which constitutes a good reason for studying cross reactivity among the members of family Euphorbiaceae, in the future.

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[4] - Ariano R, Panzani RC, Falagiani P, Chiapella M, Augeri G. Respiratory allergy to the pollen of Mercurialis annua (Euphorbiaceae). Ann Allergy 1993;70:249-254

We have described ten cases of respiratory allergy to the pollen of Mercurialis annua in the area of Bordighera (Riviera dei Fiori) on the Italian Mediterranean coast. The incidence of sensitivity is only 0.9% in a population of 1081 patients with pollinosis. Since the Euphorbiaceae family (spurges) contains strongly sensitizing allergens (eg, seeds of Ricinus communis and latex of Hevea brasiliensis) our findings raise the possibility that respiratory allergy to the pollens of Mercurialis annua and other spurges has been underestimated throughout the world.

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[5] - Vallverdu A, Garcia-Ortega P, Martinez J, Martinez A, Esteban MI, de Molina M, et al. Mercurialis annua: characterization of main allergens and cross-reactivity with other species. Int Arch Allergy Immunol 1997;112:356-364

A multicentric study was conducted to evaluate the frequency of Mercurialis annua pollen sensitization in several areas of Spain and to select a population sample to characterize the main allergenic components in M. annua pollen. Patients were recruited from six hospitals in Spain. Out of 420 patients sensitized to pollens, 195 (46.4%) showed positive skin tests to M. annua, thus evidencing the high level of sensitization to the pollen of this plant in Spain. Thirty-seven sera with RAST class values to M. annua > or = 3 were selected for SDS-PAGE immunoblotting analysis. Two main allergenic components with molecular weights of 15.8 and 14.1 kD were detected in 59 and 51% of the sera, respectively, and they were identified as profilins. Isolation of the relevant allergens was made by affinity chromatography on a poly-L-proline-Sepharose column, followed by gel filtration and anion exchange chromatography in the micropreparative SMARTs System. A significant but low antigenic cross-reactivity between M. annua and Olea europaea, Fraxinus elatior, Ricinus communis, Salsola kali, Parietaria judaica and Artemisia vulgaris was demonstrated by several in vitro techniques.

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[6] - Vallverdu A, Garcia-Ortega P, Martinez J, Martinez A, Esteban MI, de Molina M, et al. Mercurialis annua: characterization of main allergens and cross-reactivity with other species. Int Arch Allergy Immunol 1997;112:356-364

A multicentric study was conducted to evaluate the frequency of Mercurialis annua pollen sensitization in several areas of Spain and to select a population sample to characterize the main allergenic components in M. annua pollen. Patients were recruited from six hospitals in Spain. Out of 420 patients sensitized to pollens, 195 (46.4%) showed positive skin tests to M. annua, thus evidencing the high level of sensitization to the pollen of this plant in Spain. Thirty-seven sera with RAST class values to M. annua > or = 3 were selected for SDS-PAGE immunoblotting analysis. Two main allergenic components with molecular weights of 15.8 and 14.1 kD were detected in 59 and 51% of the sera, respectively, and they were identified as profilins. Isolation of the relevant allergens was made by affinity chromatography on a poly-L-proline-Sepharose column, followed by gel filtration and anion exchange chromatography in the micropreparative SMARTs System. A significant but low antigenic cross-reactivity between M. annua and Olea europaea, Fraxinus elatior, Ricinus communis, Salsola kali, Parietaria judaica and Artemisia vulgaris was demonstrated by several in vitro techniques.

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[7] - Vallverdu A, Asturias JA, Arilla MC, Gomez-Bayon N, Martinez A, Martinez J, et al. Characterization of recombinant Mercurialis annua major allergen Mer a 1 (profilin). J Allergy Clin Immunol 1998;101:363-370

BACKGROUND: Two major allergens (Mer a 1A and Mer a 1B), tentatively identified as profilin, have been described in the euphorbiacea, Mercurialis annua. OBJECTIVES: We sought to clone and characterize these major allergens from M. annua pollen and to obtain the immunologically active and soluble recombinant allergen, which could then be used for diagnostic procedures and therapy. METHODS: Isolation of cDNA clones was performed by polymerase chain reaction amplification with degenerate primers. Expression in Escherichia coli BL21 (DE3) was carried out with a vector based in the T7 expression system, and the recombinant allergen was isolated by affinity chromatography on poly-(L-proline)-Sepharose. Electrophoretic (sodium dodecylsulfate-polyacrylamide gel electrophoresis, isoelectric focusing, and 2-dimensional polyacrylamide gel electrophoresis) and immunochemical methods (Western blot and ELISA) were used for the characterization of the recombinant allergen. RESULTS: Two cDNA inserts coding for M. annua pollen profilin (Mer a 1) were cloned and sequenced. Full-length Mer a 1 cDNA was expressed in E. coli as nonfusion protein. The final yield of recombinant Mer a 1 from the culture media after a single purification step on poly-(L-proline)-Sepharose was as much as 5 mg per liter. The reactivity of recombinant Mer a 1 with IgE antibodies present in sera from patients allergic to M. annua, Olea europaea, and Ricinus communis pollens was comparable to that of the natural counterparts, but latex profilin had no cross-reactivity with M. annua profilin. Recombinant Mer a 1 was shown to share B-epitopes with sunflower profilin. CONCLUSION: This approach is suitable for the production of defined and purified recombinant allergens, which could allow more detailed immunologic characterization of these proteins and the development of much more accurate diagnostic measures and specific anti-allergic treatments.

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[8] - Asturias JA, Arilla MC, Gomez-Bayon N, Aguirre M, Martinez A, Palacios R, et al. Cloning and immunological characterization of the allergen Hel a 2 (profilin) from sunflower pollen. Mol Immunol 1998;35:469-478

Sunflower (Helianthus annuus) sensitization is not always related with occupational allergy. We have isolated the allergen profilin (Hel a 2) from this Compositae plant, cloned and sequenced five cDNAs encoding for full-length or partial Hel a 2. Natural sunflower profilin reacted with specific IgE in the 121 sera tested, at a frequency of 30.5%. Expression of the cDNA encoding Hel a 2 in Escherichia coli and a simple purification procedure by poly-L-proline chromatography allowed immunological characterization of the recombinant allergen. Binding of monoclonal antibodies against sunflower profilin revealed that some epitopes responsible for antigen-specific IgG production were not present in the recombinant allergen. High cross-reactivity has been found between recombinant Hel a 2 and profilins from other Compositae plants and also from botanically distant plants.

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[9] - Belchi-Hernandez J, Moreno-Grau S, Sanchez-Gascon F, Bayo J, Elvira Rendueles B, Bartolomé B, et al. Sensitization to Zygophyllum fabago pollen: a clinical and immunologic study. Allergy 1998;53:241-248

Zygophyllum fabago is a herbaceous plant found widely in the Mediterranean area. There are no previous reports of its allergenicity. An aerobiologic and clinical survey was conducted in Murcia, southern Spain, to determine the quantity of airborne pollen and establish the possible role of this pollen as a cause of allergic symptoms. With a Hirst volumetric trap, we determined the atmospheric concentrations of this pollen in 1993, 1994, 1995, and 1996. Of 1180 patients tested, 181 (15.34%) had a positive skin test. To determine its allergenicity, we divided 47 patients into three groups: in group 1, all the patients had symptoms of rhinoconjunctivitis plus asthma; in groups 2 and 3, rhinoconjunctivitis. In group 1, we performed a bronchial provocation test (BPT); in groups 2 and 3, we performed nasal provocation (NPT) and conjunctival provocation (CPT) tests, respectively. SDS-PAGE was used to characterize the antigenic fractions and RAST inhibition to determine cross-reactivity with other pollens. The pollen dispersion period is from May to September (445 grains/m3). BPT was positive in 13 of 15 patients, NPT in 14 of 16 patients, and CPT in 13 of 16 patients. RAST inhibition revealed cross-reactivity with Mercurialis, Ricinus, Olea, and Betula. SDS-PAGE identified 25 IgE antibody-binding components, five of which (60, 65, 41, 38, and 15.5/14.7 kDa) were recognized by 40% of the sera. By SDS-PAGE immunoblotting with sunflower antiprofilin rabbit serum and affinity chromatography we established that the Z. fabago extract has profilin. This study shows that this pollen becomes airborne and elicits an IgE response which triggers respiratory symptoms in allergic subjects.

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[10] - Garcia-Gonzalez JJ, Bartolome-Zavala B, Del Mar Trigo-Perez M, Barcelo-Munoz JM, Fernandez-Melendez S, Negro-Carrasco MA, et al. Pollinosis to Ricinus communis (castor bean): an aerobiological, clinical and immunochemical study. Clin Exp Allergy 1999;29:1265-1275

Ricinus communis (castor bean) is a species included into the Euphorbiaceae family, common to all the warm regions of the world. Although the allergenicity of its seed is well known, references are scarce regarding the role played by its pollen as a pneumo-allergen. OBJECTIVES: To carry out an aerobiological study of this pollen in the Malaga area (southern Spain); describe the physicochemical characteristics of its most relevant allergens; and to demonstrate the existence of patients with respiratory allergy due to this pollen. METHODS: A Burkard spore trap was used for the aerobiological study from 1992 to 1996. Skin prick tests with castor bean pollen extract were performed to 1946 patients with rhinitis and/or asthma. Specific IgE levels were measured in castor bean-positive SPT patient sera. Immunochemical characterization of the most relevant allergens was performed using electrophoretic techniques. In vitro cross-reactivity studies using positive patient sera were carried out. Nasal challenge tests were done in 32 subjects randomly selected from the sensitized patient group. RESULTS: Castor bean is a perennial pollen with total annual pollen levels never exceeding 1%. One hundred and eighteen (7.7%) patients showed positive prick test (74 rhinitis, 36 rhinitis and asthma, eight asthma). Nine were monosensitized. Specific IgE levels were > or =0.35 PRU/mL in 39 (33%) of patient sera. Nasal challenge test: 10 subjects presented non-specific nasal hyperactivity, 15 were positive and seven negative. The molecular masses and isoelectric points of the main IgE-binding proteins, ranged from approximately 67-15.5/14.5 kDa and approximately 4.5-5.5, respectively. Profilin of the extract was purified by poli-L-proline-Sepharose chromatography and it appeared as one of the most frequent allergens. CONCLUSION: Castor bean pollen is an allergen which causes respiratory (mainly nasal) symptoms.

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[11] - Palosuo T, Panzani R, Singh AB, Alenius H, Turjanmaa K. Allergen cross-reactivity between proteins of the latex from Hevea brasiliensis, seeds and pollen of Ricinus communis, and pollen of Mercurialis annua, members of the Euphorbiaceae family. Allergy Asthma Proc 2002;23:141-147

Allergen cross-reactions among three strongly sensitizing Euphorbiaceae species, i.e., the rubber tree (Hevea brasiliensis), castor bean (Ricinus communis), and the Mediterranean weed Mercurialis annua were studied in Finnish patients (n = 25) allergic to natural rubber latex (NRL), but with no known exposure to castor bean or M. annua, and French patients allergic to castor bean (n = 26) or to M. annua (n = 9), but not to NRL. In immunoglobulin E (IgE)-immunoblotting, 28% of NRL-allergic patient sera recognized castor bean seed and 48% reacted to castor bean pollen proteins. Likewise, 35% of the NRL-allergic patient sera bound to M. annua pollen allergens. Nineteen percent of castor bean-allergic patients showed IgE to NRL and 8% to M. annua proteins. Sera from patients allergic to M. annua reacted in 44% to NRL, in 56% to castor bean seed, and in 78% to castor bean pollen proteins. In immunoblotting, castor bean seed extract inhibited the binding of NRL-reactive IgE to 20 kDa, 30 kDa of NRL, and 55 kDa of proteins; NRL extract, in turn, inhibited the binding of castor bean- reactive IgE to 14, 21-22, 29, and 32-34 kDa of castor bean proteins. In ELISA inhibition, NRL extract inhibited 33% of the binding of M. annua--reactive IgE of pooled sera to M. annua pollen. In conclusion, allergen cross-reactivity in vitro was observed among three botanically related Euphorbiaceae members, H. brasiliensis, R. communis, and M. annua, but the molecular specificity of the observed cross-reactions as well as their clinical significance remains to be elucidated. Allergen cross-reactivity should be taken into account in diagnostic work.

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[12] - Egger M, Mutschlechner S, Wopfner N, Gadermaier G, Briza P, Ferreira F. Pollen-food syndromes associated with weed pollinosis: an update from the molecular point of view. Allergy 2006;61:461-476

Pollinosis patients often display adverse reactions upon the ingestion of plant-derived foods as a result of immunoglobulin E (IgE) cross-reactive structures shared by pollen and food allergen sources. The symptoms of such pollen-food syndromes (PFS) or class 2 food allergies range from local oral allergy syndrome to severe systemic anaphylaxis. Two clinical syndromes, the celery-mugwort-spice syndrome and the mugwort-mustard-allergy syndrome have been described in association with weed pollinosis. However, other associations between weed pollinosis and hypersensitivity to certain kinds of food have also been observed, like the mugwort-peach, the ragweed-melon-banana, the plantain-melon, the pellitory-pistachio, the goosefoot-fruit, the Russian thistle-saffron, and the hop-celery association. The number of allergen sources involved, the allergens, and influencing factors including geography, diet, and food preparation contribute to the high clinical complexity of PFS. So far, known causative cross-reactive allergens include profilins, lipid transfer proteins, and high-molecular weight allergens and/or glycoallergens. The current usage of nonstandardized allergen extracts poses additional problems for both diagnosis and therapy of PFS patients. Further identification and characterization of involved allergens is inescapable for better understanding of PFS and vaccine development. Panels of recombinant allergens and/or hypo-allergens are promising tools to improve both PFS diagnostics and therapy.

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[13] - Singh A, Panzani RC, Singh AB. Specific IgE to castor bean (Ricinus communis) pollen in the sera of clinically sensitive patients to seeds. J Investig Allergol Clin Immunol 1997;7:169-174

Human sensitization to castor bean seeds in occupational workers and people living close to oil processing factories has been acknowledged for a long time. In view of the crossreactivity among different plant parts of the same species, we studied crossreactivity between seeds of castor bean and its pollen at the molecular level. Sera from 26 seed-positive atopics, when analyzed for ELISA aganist seed and pollen extracts of castor bean, showed binding with both seed and pollen extracts, but binding was stronger with seed extracts as compared to pollen. ELISA inhibition revealed partial similarity as pollen extract could not achieve 90% inhibition even at 100 ug/ml, and remained the same alter protein concentrations of 40 ug/ml. Antigenic extracts of seeds and pollen separated into 12 and 20 fractions on SDS-PAGE, respectively. The 26 sera studied for specific IgE binding to different fractions of seed and pollen extracts showed IgE binding in 17 and 16 cases respectively, but with weak binding to pollen fractions. The crossreactivity was confirmed with pooled sera by blot inhibition. Seed antigen completely inhibited the sera for specific IgE at 10 mg/ml protein while pollen antigen showed only partial inhibition. Crossreactivity and presence of common epitopes between seed and pollen extracts are confirmed

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[14] - Palosuo T, Panzani R, Singh AB, Alenius H, Turjanmaa K. Allergen cross-reactivity between proteins of the latex from Hevea brasiliensis, seeds and pollen of Ricinus communis, and pollen of Mercurialis annua, members of the Euphorbiaceae family. Allergy Asthma Proc 2002;23:141-147

Allergen cross-reactions among three strongly sensitizing Euphorbiaceae species, i.e., the rubber tree (Hevea brasiliensis), castor bean (Ricinus communis), and the Mediterranean weed Mercurialis annua were studied in Finnish patients (n = 25) allergic to natural rubber latex (NRL), but with no known exposure to castor bean or M. annua, and French patients allergic to castor bean (n = 26) or to M. annua (n = 9), but not to NRL. In immunoglobulin E (IgE)-immunoblotting, 28% of NRL-allergic patient sera recognized castor bean seed and 48% reacted to castor bean pollen proteins. Likewise, 35% of the NRL-allergic patient sera bound to M. annua pollen allergens. Nineteen percent of castor bean-allergic patients showed IgE to NRL and 8% to M. annua proteins. Sera from patients allergic to M. annua reacted in 44% to NRL, in 56% to castor bean seed, and in 78% to castor bean pollen proteins. In immunoblotting, castor bean seed extract inhibited the binding of NRL-reactive IgE to 20 kDa, 30 kDa of NRL, and 55 kDa of proteins; NRL extract, in turn, inhibited the binding of castor bean- reactive IgE to 14, 21-22, 29, and 32-34 kDa of castor bean proteins. In ELISA inhibition, NRL extract inhibited 33% of the binding of M. annua--reactive IgE of pooled sera to M. annua pollen. In conclusion, allergen cross-reactivity in vitro was observed among three botanically related Euphorbiaceae members, H. brasiliensis, R. communis, and M. annua, but the molecular specificity of the observed cross-reactions as well as their clinical significance remains to be elucidated. Allergen cross-reactivity should be taken into account in diagnostic work.

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[15] - Singh BP, Verma J, Sridhara S, Rai D, Makhija N, Gaur SN, et al. Immunobiochemical characterization of Putranjiva roxburghii pollen extract and cross-reactivity with Ricinus communis. Int Arch Allergy Immunol 1997;114:251-257

Putranjiva roxburghii (PR) pollen has been found to be an important aeroallergen for type I hypersensitivity. In the present study, the IgE binding proteins of PR pollen have been characterized and compared with pollen allergens of Ricinus communis (RC) belonging to family Euphorbiaceae. On isoelectric focusing, PR pollen extract resolved into 35 bands (pI 3-9), whereas SDS-PAGE separated it into 18 protein components (MW 14-100 kD). Pooled patient's sera (ID +ve to PR) recognized 12 allergenic proteins in Putranjiva and five of them (MWs 92, 80, 55, 43 and 30 kD) showed immunologic reactivity to most of the sera samples tested individually by immunoblot. A number of shared allergenic proteins (MWs 92, 80, 66, 50, 43 and 14 kD) were observed between PR and RC pollen extracts on immunoblot using Putranjiva allergic serum pool. Inhibition in the binding for most of PR pollen allergenic proteins was obtained with higher concentration of RC extract than PR itself, depicting the presence of cross-reacting allergens in both. Putranjiva pollen extract was fractionated by a combination of DEAE Sephadex-A 50 and Sephadex-G 200 column chromatography. Periodate deglycosylation of western blotted PR extract and Put I fraction indicated the involvement of carbohydrate moieties in the allergenic activity. Of the two fractions from Put I (Ia and Ib), Put Ib was found to be the most allergenic protein by ELISA inhibition. Dot blot analysis with individual patients sera identified it as a major allergen of PR.

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[16] - Belchi-Hernandez J, Moreno-Grau S, Sanchez-Gascon F, Bayo J, Elvira Rendueles B, Bartolomé B, et al. Sensitization to Zygophyllum fabago pollen: a clinical and immunologic study. Allergy 1998;53:241-248

Zygophyllum fabago is a herbaceous plant found widely in the Mediterranean area. There are no previous reports of its allergenicity. An aerobiologic and clinical survey was conducted in Murcia, southern Spain, to determine the quantity of airborne pollen and establish the possible role of this pollen as a cause of allergic symptoms. With a Hirst volumetric trap, we determined the atmospheric concentrations of this pollen in 1993, 1994, 1995, and 1996. Of 1180 patients tested, 181 (15.34%) had a positive skin test. To determine its allergenicity, we divided 47 patients into three groups: in group 1, all the patients had symptoms of rhinoconjunctivitis plus asthma; in groups 2 and 3, rhinoconjunctivitis. In group 1, we performed a bronchial provocation test (BPT); in groups 2 and 3, we performed nasal provocation (NPT) and conjunctival provocation (CPT) tests, respectively. SDS-PAGE was used to characterize the antigenic fractions and RAST inhibition to determine cross-reactivity with other pollens. The pollen dispersion period is from May to September (445 grains/m3). BPT was positive in 13 of 15 patients, NPT in 14 of 16 patients, and CPT in 13 of 16 patients. RAST inhibition revealed cross-reactivity with Mercurialis, Ricinus, Olea, and Betula. SDS-PAGE identified 25 IgE antibody-binding components, five of which (60, 65, 41, 38, and 15.5/14.7 kDa) were recognized by 40% of the sera. By SDS-PAGE immunoblotting with sunflower antiprofilin rabbit serum and affinity chromatography we established that the Z. fabago extract has profilin. This study shows that this pollen becomes airborne and elicits an IgE response which triggers respiratory symptoms in allergic subjects.

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[17] - Singh A, Panzani RC, Singh AB. Specific IgE to castor bean (Ricinus communis) pollen in the sera of clinically sensitive patients to seeds. J Investig Allergol Clin Immunol 1997;7:169-174

Human sensitization to castor bean seeds in occupational workers and people living close to oil processing factories has been acknowledged for a long time. In view of the crossreactivity among different plant parts of the same species, we studied crossreactivity between seeds of castor bean and its pollen at the molecular level. Sera from 26 seed-positive atopics, when analyzed for ELISA aganist seed and pollen extracts of castor bean, showed binding with both seed and pollen extracts, but binding was stronger with seed extracts as compared to pollen. ELISA inhibition revealed partial similarity as pollen extract could not achieve 90% inhibition even at 100 ug/ml, and remained the same alter protein concentrations of 40 ug/ml. Antigenic extracts of seeds and pollen separated into 12 and 20 fractions on SDS-PAGE, respectively. The 26 sera studied for specific IgE binding to different fractions of seed and pollen extracts showed IgE binding in 17 and 16 cases respectively, but with weak binding to pollen fractions. The crossreactivity was confirmed with pooled sera by blot inhibition. Seed antigen completely inhibited the sera for specific IgE at 10 mg/ml protein while pollen antigen showed only partial inhibition. Crossreactivity and presence of common epitopes between seed and pollen extracts are confirmed

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Pollen de mercuriale

Pollen de ricin

Rubriques

Dans la même rubrique

Les Amaranthacées

Les ambroisies

L’armoise

Les Astéracées (Composées)

Les plantains

Les Pariétaires