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Pollen Extract (pollen + extract)
Selected AbstractsLactoferrin decreases pollen antigen-induced allergic airway inflammation in a murine model of asthmaIMMUNOLOGY, Issue 2 2006Marian L. Kruzel Summary Pollen grains contain reduced nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidases and in contact with mucosal surfaces generate superoxide anion (O2,,). In the presence of iron, O2,, may be converted to more reactive oxygen radicals, such as to H2O2 and/or ,OH, which may augment antigen-induced airway inflammation. The aim of the study was to examine the impact of lactoferrin (LF), an iron-binding protein, on ragweed (Ambrosia artemisiifolia) pollen extract (RWE)-induced cellular oxidative stress levels in cultured bronchial epithelial cells and accumulation of inflammatory and mucin-producing cells in airways in a mouse model of allergic airway inflammation. Results show that LF lowered RWE-induced increase in cellular reactive oxygen species (ROS) levels in bronchial epithelial cells. Most importantly, LF significantly decreased accumulation of eosinophils into airways and subepithelium of intranasally challenged, sensitized mice. LF also prevented development of mucin-producing cells. Amb a 1, the major allergenic ragweed pollen antigen lacking NAD(P)H oxidase activity, induced low-grade airway inflammation. When administered along with glucose oxidase (G-ox), a superoxide-generating enzyme, Amb a 1 induced robust airway inflammation, which was significantly lowered by LF. Surprisingly, LF decreased also inflammation caused by Amb a 1 alone. Iron-saturated hololactoferrin had only a marginal effect on RWE-induced cellular ROS levels and RWE- or Amb a 1 plus G-ox-induced inflammation. We postulate that free iron in the airways chemically reduces O2,, to more reactive species which augment antigen-induced inflammation in a mouse model of asthma. Our results suggest the utility of LF in human allergic inflammatory disorders. [source] Phosphorylation of Microtubule-associated Protein SB401 from Solanum berthaultii Regulates Its Effect on MicrotubulesJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 3 2009Bao-Quan Liu Abstract We reported previously that the protein SB401 from Solanum berthaultii binds to and bundles both microtubules and F-actin. In the current study, we investigated the regulation of SB401 activity by its phosphorylation. Our experimental results showed that the phosphorylation of SB401 by casein kinase II (CKII) downregulates the activities of SB401, namely the bundling of microtubules and enhancement of the polymerization of tubulin. However, phosphorylation of SB401 had no observable effect on its bundling of F-actin. Further investigation using extract of potato pollen indicated that a CKII-like kinase may exist in potato pollen. Antibodies against CKII alpha recognized specifically a major band from the pollen extract and the pollen extract was able to phosphorylate the SB401 protein in vitro. The CKII-like kinase showed a similar ability to downregulate the bundling of microtubules. Our experiments demonstrated that phosphorylation plays an important role in the regulation of SB401 activity. We propose that this phosphorylation may regulate the effects of SB401 on microtubules and the actin cytoskeleton. [source] Antinociceptive and antiinflammatory activities of pine (Pinus densiflora) pollen extractPHYTOTHERAPY RESEARCH, Issue 5 2007Eun-Mi Choi Abstract The study aimed to evaluate the antinociceptive and antiinflammatory activity of pine (Pinus densiflora) pollen in mice. The antinociceptive activity was determined using acetic acid-induced abdominal constriction and formalin-induced licking, and the hot plate test. Antiinflammatory effects were evaluated using carrageenan- and formalin-induced paw edema, and arachidonic acid-induced ear edema in mice. The ethanol extract of pine pollen (100 and 200 mg/kg, p.o.) produced a significant inhibition of both phases of the formalin pain test in mice, a reduction in mouse writhing induced by acetic acid and an elevation of the pain threshold in the hot plate test in mice. The pine pollen extract also produced a significant inhibition of carrageenan- and formalin-induced paw edema as well as arachidonic acid-induced ear edema in mice. The inhibitions were similar to those produced by aminopyrine and indomethacin, p.o. The different polyphenols found in pine pollen could account for the antinociceptive and antiinflammatory actions. The results obtained indicate that the extract possesses analgesic and antiinflammatory effects. Copyright © 2007 John Wiley & Sons, Ltd. [source] Seasonal changes in suppressive capacity of CD4+ CD25+ T cells from patients with hayfever are allergen-specific and may result in part from expansion of effector T cells among the CD25+ populationCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2009A. E. Anderson Summary Background Suppression of allergen-stimulated peripheral blood CD4+ CD25, effector T cells by CD4+ CD25+ regulatory T cells obtained from subjects with allergic rhinoconjunctivitis is reduced during the pollen season when compared with out of season. Objective We examined possible explanations for this effect of seasonal pollen exposure on suppression of allergen responses. Methods CD4+ CD25, and CD4+ CD25+ T cells were isolated from blood obtained from 44 volunteers with allergic rhinoconjunctivitis during and out of the UK grass pollen season. Co-cultures were performed with grass pollen extract and house dust mite (HDM) to examine allergen specificity. The frequency of IL-5 and IL-10 producing cells was determined by ELISPOT and the expression of T cell activation markers and the CD25+ regulatory T cell-associated transcription factor Foxp3 were examined. Lactic acid stripping of IgE was used to determine IgE dependence of T cell responses. Results The seasonal reduction in suppression by CD4+ CD25+ T cells was confirmed and was shown to be allergen specific because suppression of HDM-stimulated cultures was not affected significantly. The CD4+ CD25+ population contained IL-5 and IL-10 producing cells but increases in their frequencies with seasonal pollen exposure were not significant. Both activation marker and Foxp3 expression increased during the pollen season. IgE stripping reduced CD4+ and CD4+ CD25, T cell responses to allergen, but had no effect on suppression by CD4+ CD25+ T cells. Conclusion The seasonal reduction in suppression of grass pollen-stimulated effector T cells by CD4+ CD25+ T cells is allergen specific and cannot be explained by increased IgE-facilitated allergen presentation. We suggest that changes in the proportion of effector to regulatory T cells among the CD25+ population isolated may partially explain these findings, and that trafficking to the site of allergic disease may reduce allergen-specific regulatory T cell numbers in peripheral blood. [source] MALDI-TOF MS analysis of labile Lolium perenne major allergens in mixesCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2008S. G. Irañeta Summary Background It is well known that allergen extracts used for specific therapy of allergic disorders are commonly stored as mixtures, causing an alteration of its stability. Objective The aim of this report is to identify pollen allergens susceptible to degradation during storage of mixtures containing different sources of proteases in the absence of glycerol as a preserving agent. Methods Mixes containing Lolium perenne (Lol p) pollen extract with either Aspergillus fumigatus or Periplaneta americana extracts were prepared and co-incubated for 90 days at 4 °C. Samples were taken off at fixed times and comparatively tested by in vitro and in vivo assays with atopic patients. Selected pollinic allergens were subjected to MALDI-TOF MS analysis. Results ELISA inhibition evidenced the loss of potency from ryegrass extract, and immunoblotting assays showed the degradation of specific pollinic allergens during storage of mixtures containing protease-rich sources. An in vivo intradermal skin assay confirmed the gradual loss of the biological activity of L. perenne pollen extract co-incubated with non-related protease-rich extracts in comparison with that of the control pollen extract. MALDI-TOF MS analysis allowed us to determine that Lol p 1 and Lol p 5 are susceptible to proteolysis whereas Lol p 4 was found to be resistant to degradation during storage. Conclusions Lol p 1 and Lol p 5 degradation is responsible for the loss of the biological activity of L. perenne pollen extract when co-incubated with protease-rich fungal and cockroach extracts in the same vial for months in the absence of glycerol as a preserving agent. The integrity of these major allergens must be preserved to increase the vaccine stability and to assure efficacy when mixes are used for immunotherapy. [source] Immunoreactivity profile of peripheral blood mononuclear cells from patients with ragweed-induced allergic rhinitisCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2007J. Sun Summary Background Seasonal rhinitis is manifested by a series of nasal symptoms in response to exposure to seasonal allergens including ragweed pollen. Understanding its immunological mechanisms may help to better manage the disease. Objective We sought to determine comprehensively ragweed-induced cytokine and chemokine production by peripheral blood mononuclear cells from normal individuals and patients with seasonal rhinitis sensitized to ragweed pollen, and to assess its regulation by exogenous IL-10. Methods Cells were cultured in the presence or absence of a purified ragweed pollen extract with or without exogenous IL-10. Cytokines and chemokines were measured in the supernatant. Gene expression was evaluated using real-time quantitative reverse transcription PCR. Results Ragweed stimulation significantly increased the production of the Th2-associated cytokines IL-5, IL-9 and IL-13, the chemokines CCL17 and CCL22 and the regulatory cytokine IL-10 in allergic patients, whereas transforming growth factor-, (TGF-,) production was increased only in normal individuals. No difference was detected between groups in the production of the Th1 cytokine IFN-, or the Th1-affiliated chemokines CXCL10 and CXCL11. Exogenous IL-10 significantly suppressed spontaneous and induced production of both Th1- and Th2-associated cytokines and chemokines. Conclusion Our work demonstrated that locally manifested allergic rhinitis is underlined by a systemic Th2 immune response specific to allergens. The molecular pathogenesis of allergic rhinitis may be linked to a compromised allergen-specific immune regulation, e.g., reduced spontaneous and allergen-induced TGF-, production in patients compared with healthy controls. Our data also show that IL-10 inhibits both the effector and directional mechanisms of allergen-specific immune response, further supporting its potential therapeutic benefit in preventing and treating allergic diseases. [source] Diagnosis of Parietaria judaica pollen allergy using natural and recombinant Par j 1 and Par j 2 allergensCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2007R. González-Rioja Summary Background Parietaria judaica pollen is one of the main causes of allergic diseases in the Mediterranean area and contains two major allergens, called Par j 1 and Par j 2. Objective To evaluate the diagnostic potential of natural and recombinant forms of Par j 1 and Par j 2 in comparison with standardized P. judaica pollen extract. Methods Thirty patients allergic to P. judaica pollen and 15 control patients were investigated. Skin prick tests and determination of specific IgE levels were performed with commercial P. judaica extract, natural Par j 1 and Par j 2, and recombinant forms of both allergens expressed in P. pastoris. Results The whole group of patients with allergy to P. judaica had a positive skin test reaction to purified nPar j 1,Par j 2 and rPar j 2 at 5 ,g/mL, and no false-positive reactions were detected. Natural and recombinant Par j 1 and Par j 2 showed no significantly different responses in skin tests compared with P. judaica extract. A high correlation was found between the serum-specific IgE levels to P. judaica extract vs. natural (R=0.996; P<0.001) and recombinant allergens (R=0.887 and 0.982 for rPar j 1 and rPar j 2, respectively; P<0.001). rPar j 2 displayed a 100% sensitivity and specificity among P. judaica -allergic patients. Conclusions In vivo and in vitro diagnosis of P. judaica pollen allergy could be simplified using rPar j 2. This protein showed comparable IgE response and skin prick reactivity with those produced by P. judaica pollen extract. [source] Pho d 2, a major allergen from date palm pollen, is a profilin: cloning, sequencing, and immunoglobulin E cross-reactivity with other profilinsCLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2005J. A. Asturias Summary Background Up to now, some date palm pollen (DPP) allergens have been described but very few data are available about their molecular nature. The aim of this study was to identify and characterize Pho d 2, a major allergen from this pollen. Methods Sera from 25 patients allergic to DPP were analysed by immunoblotting. Purification of DPP profilin was performed by poly- l -proline affinity chromatography. Profilin-encoding cDNA from DPP was cloned by using a RT-PCR strategy and recombinant allergen was expressed as a non-fusion protein in Escherichia coli. Natural and recombinant Pho d 2 were investigated by means of enzyme allergosorbent test to compare the immunologic properties of both allergens and to analyse cross-reactivity with other profilins. Results A 14.4 kDa protein was identified as a major allergen in DPP extract. Purification, cloning, heterologous expression, and inhibition experiments identified it as profilin (Pho d 2). Pho d 2 comprises 131 amino acids and has high sequence identity with other allergenic food and pollen profilins. The prevalence of specific IgE antibody reactivity to natural Pho d 2 by ELISA was 56% and 64% by skin prick test (SPT). Pho d 2 is an important allergen as it is responsible for more than 70% of the IgE reactivity to the pollen extract. IgE directed against Pho d 2 showed a strong cross-reactivity with other profilins such as those from olive tree and grass pollens. Conclusion Pho d 2, a 14.4 kDa protein identified as profilin, is a major and relevant allergen in DPP, as confirmed by SPT and thereby may elicit clinical symptoms in sensitized patients. [source] Effect of various stabilizing agents on Imperata cylindrica grass pollen allergen extractCLINICAL & EXPERIMENTAL ALLERGY, Issue 1 2003K. M. Bijli Summary Background Allergen extracts are unstable, heat labile or susceptible to proteases. Stability of allergen extracts is important for proper diagnosis and therapy of allergic disorders. Objective The present study was undertaken to determine the preservation and stabilization conditions of Imperata cylindrica (Ic) grass pollen extract. Methods The Ic extract was kept with 0.1 m,-aminocaproic acid (EACA), 0.75 m sucrose, 5% glycerol, 0.03% human serum albumin (HSA) or 0.4% phenol for different time periods. The extracts were stored for 3, 6 and 12 months each at 4 °C, 4 °C with daily exposure to room temperature (RT) for 1 h, and RT. The quality of extracts was analysed by SDS-PAGE, Western blot, ELISA, ELISA inhibition and skin test. Results Extracts kept with EACA and sucrose retained most of the protein bands followed by glycerol as determined by SDS-PAGE and Western blot during all storage periods and conditions in comparison with standard extracts. The extracts kept with HSA, phenol and without preservative (WP) showed protein degradation below 33 kDa after 3 months storage at all conditions. However, a 67-kDa allergen was stable in these extracts. EACA extract required 75 to 120 ng of protein for 50% inhibition in IgE binding under different conditions, whereas standard extract required 70 ng for the same. ELISA also demonstrated high allergenic reactivity of EACA extract. ID test on allergy patients with EACA extract demonstrated same allergenic potency as that of standard extract. Conclusion EACA is the best preservative/stabilizing agent of Ic pollen extract, followed by sucrose and glycerol. Ic extract kept with phenol, HSA and without preservative showed degradation within 3 months. EACA preserved extract is equally potent as that of standard extract up to 1 year's storage. [source] The allergen profile of ash (Fraxinus excelsior) pollen: cross-reactivity with allergens from various plant speciesCLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2002V. Niederberger Summary Background Ash, a wind-pollinated tree belonging to the family Oleaceae, is distributed world-wide and has been suggested as a potent allergen source in spring time. Objective The aim of this study was to determine the profile of allergen components in ash pollen in order to refine diagnosis and therapy for patients with sensitivity to ash pollen Methods The IgE reactivity profile of 40 ash pollen-allergic patients was determined by immunoblotting. Antibodies raised to purified pollen allergens from tree and grass pollens were used to identify cross-reactive structures in ash pollen extract. IgE immunoblot inhibition studies were performed with recombinant and natural pollen allergens to characterize ash pollen allergens and to determine the degree of cross-reactivity between pollen allergens from ash, olive, birch, grasses and weeds. Results The allergen profile of ash pollen comprises Fra e 1, a major allergen related to the major olive allergen, Ole e 1, and to group 11 grass pollen allergens, the panallergen profilin, a two EF-hand calcium-binding protein, a pectinesterase-like molecule and an allergen sharing epitopes with group 4 grass pollen allergens. Thus, the relevant allergens of ash are primarily allergens that share epitopes with pollen allergens from other tree, grass and weed species. Conclusions Allergic symptoms to ash pollen can be the consequence of sensitization to cross-reactive allergens from other sources. The fact that ash pollen-allergic patients can be discriminated on the basis of their specific IgE reactivity profile to highly or moderately cross-reactive allergens has implications for the selection of appropriate forms of treatment. [source] Identification and characterization of a group 2 conifer pollen allergen from Chamaecyparis obtusa, a homologue of Cry j 2 from Cryptomeria japonicaCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2000Yasueda Background Not only Cryptomeria japonica (Japanese cedar) pollen but also that of Chamaecyparis obtusa (Japanese cypress) induces the allergic symptoms of Japanese cedar pollinosis. However, allergens from C. obtusa pollen have not been as well characterized as those from C. japonica pollen. Objective We sought to identify and characterize a homologue of the second major allergen of C. japonica pollen, Cry j 2, from the pollen of C. obtusa. Methods An allergen homologous to Cry j 2 was identified in C. obtusa pollen extract by immunoblot analysis, probed with anti-Cry j 2 monoclonal antibodies and purified by a series of column chromatographic steps. Results The allergen isolated from the extract showed a slightly diffuse band of 45 kDa and closely spaced double-bands of 42 and 45 kDa on SDS-PAGE, under reducing and non-reducing conditions, respectively; the bands were approximately 5,7 kDa larger than those of Cry j 2. In 24 of 30 residues, the N-terminal amino acid sequence of the allergen was identical with corresponding sequence in Cry j 2. Most patients with pollinosis who were IgE antibody-positive to Cry j 2 were shown to be IgE antibody-positive to this allergen, and the IgE antibody levels to both allergens were highly correlated. Conclusion The results indicate that the allergen isolated from C. obtusa pollen in this study is a homologue of Cry j 2. The allergen was designated as Cha o 2 according to the WHO/IUIS Allergen Nomenclature Subcommittee recommendation. [source] Immunoglobulin E reactivity to Arizona cypress pollen extracts: evidence for a 35-kDa allergenALLERGY, Issue 11 2009Y. Shahali No abstract is available for this article. [source] Heterogeneity of commercial timothy grass pollen extractsCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2008M. Focke Summary Background The diagnosis and specific immunotherapy of allergy is currently performed with allergen extracts prepared from natural allergen sources. Objective To analyse commercial timothy grass pollen allergen extracts used for in vivo diagnosis regarding their qualitative and quantitative allergen composition and in vivo biological activity. Methods Antibodies specific for eight timothy grass pollen allergens (Phl p 1, Phl p 2, Phl p 4, Phl p 5, Phl p 6, Phl p 7, Phl p 12, Phl p 13) were used to detect these allergens in timothy grass pollen extracts from four manufacturers by immunoblotting. ELISA assays were developed and used to quantify the three major allergens (Phl p 1, Phl p 2, Phl p 5) in the extracts. The magnitude of skin responses to the four extracts was studied by skin prick testing in 10 grass pollen-allergic patients. Results The allergen extracts showed broad variations in protein compositions and amounts (24.1,197.7 ,g/mL extract). Several allergens could not be detected in certain extracts or appeared degraded. A considerable variability regarding the contents of major allergens was found (Phl p 1: 32,384 ng/mL; Phl p 2: 1128,6530 ng/mL, Phl p 5: 40,793 ng/mL). Heterogeneous skin test results were obtained with the extracts in grass pollen-allergic patients. Conclusions Timothy grass pollen extracts from different manufacturers exhibit a considerable heterogeneity regarding the presence of individual allergens and hence yield varying in vivo test results. Problems related to the use of natural grass pollen allergen extracts may be circumvented by using defined recombinant grass pollen allergens. [source] Biological characterization of glutaraldehyde-modified Parietaria judaica pollen extractsCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2004I. Ibarrola Summary Background Allergoids are widely used in specific immunotherapy (SIT) for the treatment of IgE-mediated allergic diseases, but all techniques for standardization of conventional allergic extracts may not be appropriate for standardization of a glutaraldehyde (GA)-modified extract because of the unique characteristics of these extracts. Objective To assess an accurate methodology for standardization of chemically modified extracts. Methods GA-modified extracts from Parietaria judaica pollen were purified by diafiltration. Biochemical properties were investigated by determination of amino groups, chromatography, and SDS-PAGE. The IgE-binding activity was determined by skin prick test, enzyme allergosorbent test inhibition, basophil activation, and histamine release tests. Peripheral blood mononuclear cells (PBMCs) from P. judaica pollen-allergic subjects were stimulated with either native or allergoid extracts, and proliferation was measured. Results Biochemical data indicated a high degree of allergen polymerization resulting in extract components higher than 100 kDa. IgE-binding activity, both in vivo and in vitro, was reduced by more than 99.8%. Both allergen and allergoid induced PBMC proliferation and synthesis of blocking IgG antibodies at similar rates. Moreover, no evidence of introduction of new determinants by chemical modification was found. Conclusions The preparation of GA-modified extracts by diafiltration is faster and more reliable than previous chromatographic methods. These modified extracts have drastically reduced their allergenicity while maintaining their immunogenicity, and therefore they can be used in safer and shortened schedules of SIT. [source] Systemic reactions to immunotherapy: influence of composition and manufacturerCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2003G. Gastaminza Summary Background Although immunotherapy clearly demonstrated the benefit of reducing allergic symptoms, it has the drawback of adverse events, mainly systemic reactions that could be very inconvenient for patients and even life-threatening. Objective The aim of the present study was to assess the incidence of systemic reactions to immunotherapy in a large number of patients, and its potential relationship with the characteristics of therapy, such as allergen composition or manufacturing laboratory. Methods This study analysed the administration of specific immunotherapy during a period of 5 years, involving 1212 patients affected by respiratory hypersensitivity or hymenoptera venom anaphylaxis. Commercial extracts were supplied by five different laboratories. All the patients were attended at an out-clinic immunotherapy unit by the same experienced staff. Immunotherapy was given following a conventional schedule, modified according the usual recommendations. Results A total of 250 adverse reactions have been recorded, resulting in a frequency of 0.84% over the total number of injections. Seventy-nine of them (32%) were systemic reactions (0.27% SR/injection). The 79 systemic reactions were observed in 60 patients (5% of the patients). The frequency of systemic reactions was significantly lower (P < 0.01) on the group of mites than on the other groups. The frequency of systemic reactions varies according to the manufacturing laboratory. In the case of mite extracts, although one of the laboratories had a lower frequency of adverse systemic reactions, it did not reach the level of statistical significance. However, in relation to pollen extracts, preparations of one of the manufacturers had a significantly lower frequency of systemic reactions. Concerning the time of occurrence, 27% of systemic reactions were delayed, thus they appeared at least 30 min after the vaccine injection, most of them due to pollen extracts. Conclusion This is a preliminary study to evaluate the factors that could facilitate the appearance of systemic reactions demonstrating that not only the composition but also the manufacturer is connected to systemic reactions. Although further studies are needed to clearly establish the influence of manufacturer on frequency and time of appearance of systemic reactions, it seems necessary to reach a wide consensus on allergen extract standardization methods. [source] | ||||||||||