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1.
Int J Mol Sci ; 22(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299235

RESUMO

The allergenic and inflammatory potential of proteins can be enhanced by chemical modification upon exposure to atmospheric or physiological oxidants. The molecular mechanisms and kinetics of such modifications, however, have not yet been fully resolved. We investigated the oligomerization and nitration of the grass pollen allergen Phl p 5 by ozone (O3), nitrogen dioxide (NO2), and peroxynitrite (ONOO-). Within several hours of exposure to atmospherically relevant concentration levels of O3 and NO2, up to 50% of Phl p 5 were converted into protein oligomers, likely by formation of dityrosine cross-links. Assuming that tyrosine residues are the preferential site of nitration, up to 10% of the 12 tyrosine residues per protein monomer were nitrated. For the reaction with peroxynitrite, the largest oligomer mass fractions (up to 50%) were found for equimolar concentrations of peroxynitrite over tyrosine residues. With excess peroxynitrite, the nitration degrees increased up to 40% whereas the oligomer mass fractions decreased to 20%. Our results suggest that protein oligomerization and nitration are competing processes, which is consistent with a two-step mechanism involving a reactive oxygen intermediate (ROI), as observed for other proteins. The modified proteins can promote pro-inflammatory cellular signaling that may contribute to chronic inflammation and allergies in response to air pollution.


Assuntos
Phleum/metabolismo , Proteínas de Plantas/metabolismo , Rinite Alérgica Sazonal/metabolismo , Alérgenos/química , Cinética , Nitratos/metabolismo , Dióxido de Nitrogênio/química , Óxidos de Nitrogênio , Oxidantes , Ozônio/química , Ácido Peroxinitroso/química , Proteínas de Plantas/análise , Poaceae/metabolismo , Pólen/metabolismo , Proteínas/química , Rinite Alérgica Sazonal/fisiopatologia
2.
Mol Immunol ; 136: 98-109, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34098345

RESUMO

The Poaceae family is composed of 12,000 plant species. Some of these species produce highly allergenic anemophilous pollen grains (PGs). Phleum pratense pollen grains (PPPGs) emerged as a model for studies related to grass allergy. The biochemical composition of allergenic PGs has not yet been fully described despite potential health effects of PG constituents other than allergenic proteins. This review brings together the information available in literature aiming at creating a comprehensive picture of the current knowledge about the chemical composition of allergenic PGs from timothy grass. PPPGs have an average diameter between 30-35 µm and the mass of a single PG was reported between 11 and 26 ng. The pollen cytoplasm is filled with two types of pollen cytoplasmic granules (PCGs): the starch granules and the polysaccharide particles (p-particles). Starch granules have a size between 0.6-2.5 µm with an average diameter of 1.1 µm (estimated number of 1000 granules per PG) while p-particles have a size ranging around 0.3 to 0.4 µm (estimated number between 61,000-230,000 p-particles per PG). The rupture of PG induces the release of PCGs and the dispersion of allergens in the inhalable fraction of atmospheric aerosol. PPPGs are composed of sporopollenin, sugars, polysaccharides, starch, glycoproteins (including allergens), amino-acids, lipids, flavonoids (including isorhamnetin), various elements (the more abundant being Si, Mg and Ca), phenolic compounds, phytoprostanoids, carotenoids (pigments) metals and adsorbed pollutants. PPPG contains about a hundred different proteins with molecular masses ranging from 10 to 94 kDa, with isoelectric points from 3.5-10.6. Among these proteins, allergens are classified in eleven groups from 1 to 13 with allergens from groups 1 and 5 being the major contributors to Phl p pollen allergy. Major allergen Phl p 5 was quantified in PPPGs by several studies with concentration ranging from 2.7 and 3.5 µg.mg-1 in unpolluted environment. Values for other allergens are scarce in literature; only one quantitative assessment exists for allergen groups Phl p 1, 2 and 4. The extractible lipid fraction of PPPGs is estimated between 1.7-2.2% of the total PG mass. The main chemical families of lipids reported in PPPGs are: alkanes, alkenes, alcohols, saturated and unsaturated fatty acids, di- and tri-hydroxylated fatty acids, aldehydes and sterols. Several lipid compounds with potential adjuvant effects on allergy have been specifically quantified in PPPGs: E2-like prostaglandin (PGE2), B4-like leukotriene (LTB4), unsaturated fatty acids (linoleic and linolenic acids and their hydroxylated derivatives), adenosine, vitamins and phenolic compounds. Some other biochemical characteristics such as NAD(P)H oxidase, protease activity and pollen microbiome were described in the literature. The bioaccessibility in physiological conditions has not been described for most biochemicals transported by allergenic PPPGs. There is also a considerable lack of knowledge about the potential health effects of pollen constituents other than allergens. The variability of pollen composition remains also largely unknown despite its importance for plant reproduction and allergy in an environment characterized by chemical pollution, climate change and loss of biodiversity.


Assuntos
Phleum/química , Proteínas de Plantas/química , Proteínas de Plantas/imunologia , Pólen/química , Pólen/imunologia , Alérgenos/química , Alérgenos/imunologia , Asma/imunologia , Asma/patologia , Grânulos Citoplasmáticos/imunologia , Humanos , Phleum/imunologia , Rinite Alérgica Sazonal/imunologia , Rinite Alérgica Sazonal/patologia
3.
Mol Immunol ; 136: 1-7, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34051631

RESUMO

BACKGROUND: Allergen quantification has become a relevant parameter for allergen extract characterization and to guarantee the consistency of the manufacturing process at allergen immunotherapy. The aim of this study was to develop and validate a method to quantify the major allergen Phl p 1 based on a prediction of the antigenic regions by immunoinformatic strategies. METHODS: Phl p 1 was purified from a Phleum pratense native extract by chromatographic methods. Immunoinformatic tools were used to predict B-cell epitopes. In silico predictions were verified by mapping linear epitopes with a peptide library and used to select the appropriate regions for producing the mAbs to develop an ELISA method, which was validated. Phl p 1 was quantified in 24 batches of P. pratense extracts. RESULTS: Phl p 1 was purified with 95 % purity and completely functional. Eight B-cell epitopes in each of the two Phl p 1 isoforms were predicted. Two of the predicted B-cell epitopes overlapped with the experimentally determined peptides recognized by two mAbs selected for development of the kit. The quantification method demonstrated to be specific to Phl p 1, linear, accurate and precise in the range from 7.7 to 123.3 µg/mg. Mean Phl p 1 content was 28.95 µg of allergen/mg of lyophilized native extract and 44.23 µg of allergen/mg of lyophilized depigmented extract. CONCLUSIONS: An ELISA method for measuring Phl p 1 in P. pratense extracts was developed and validated by producing the appropriate mAbs against epitopes selected by immunoinformatic tools.


Assuntos
Alérgenos/análise , Alérgenos/imunologia , Anticorpos Monoclonais/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos de Linfócito B/imunologia , Proteínas de Plantas/análise , Proteínas de Plantas/imunologia , Sequência de Aminoácidos , Biologia Computacional , Mapeamento de Epitopos , Humanos , Biblioteca de Peptídeos , Phleum/química , Phleum/imunologia
4.
J Allergy Clin Immunol ; 148(4): 1061-1071.e11, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33819508

RESUMO

INTRODUCTION: There is no detailed comparison of allergen-specific immunoglobulin responses following sublingual immunotherapy (SLIT) and subcutaneous immunotherapy (SCIT). OBJECTIVE: We sought to compare nasal and systemic timothy grass pollen (TGP)-specific antibody responses during 2 years of SCIT and SLIT and 1 year after treatment discontinuation in a double-blind, double-dummy, placebo-controlled trial. METHODS: Nasal fluid and serum were obtained yearly (per-protocol population, n = 84). TGP-specific IgA1, IgA2, IgG4, IgG, and IgE were measured in nasal fluids by ELISA. TGP-specific IgA1, IgA2, and Phleum pratense (Phl p)1, 2, 4, 5b, 6, 7, 11, and 12 IgE and IgG4 were measured in sera by ELISA and ImmunoCAP, respectively. RESULTS: At years 2 and 3, TGP-IgA1/2 levels in nasal fluid were elevated in SLIT compared with SCIT (4.2- and 3.0-fold for IgA1, 2.0- and 1.8-fold for IgA2, respectively; all P < .01). TGP-IgA1 level in serum was elevated in SLIT compared with SCIT at years 1, 2, and 3 (4.6-, 5.1-, and 4.7-fold, respectively; all P < .001). Serum TGP-IgG level was higher in SCIT compared with SLIT (2.8-fold) at year 2. Serum TGP-IgG4 level was higher in SCIT compared with SLIT at years 1, 2, and 3 (10.4-, 27.4-, and 5.1-fold, respectively; all P < .01). Serum IgG4 levels to Phl p1, 2, 5b, and 6 were increased at years 1, 2, and 3 in SCIT and SLIT compared with placebo (Phl p1: 11.8- and 3.9-fold; Phl p2: 31.6- and 4.4-fold; Phl p5b: 135.5- and 5.3-fold; Phl p6: 145.4- and 14.7-fold, respectively, all at year 2 when levels peaked; P < .05). IgE to TGP in nasal fluid increased in the SLIT group at year 2 but not at year 3 compared with SCIT (2.8-fold; P = .04) and placebo (3.1-fold; P = .02). IgA to TGP and IgE and IgG4 to TGP components stratified participants according to treatment group and clinical response. CONCLUSIONS: The observed induction of IgA1/2 in SLIT and IgG4 in SCIT suggest key differences in the mechanisms of action.


Assuntos
Alérgenos/imunologia , Dessensibilização Imunológica , Imunoglobulinas/imunologia , Phleum/imunologia , Pólen/imunologia , Administração Sublingual , Adulto , Linfócitos B/imunologia , Método Duplo-Cego , Feminino , Humanos , Imunoglobulinas/sangue , Injeções Subcutâneas , Masculino , Mucosa Nasal/imunologia
5.
Allergy ; 76(8): 2575-2586, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33742477

RESUMO

BACKGROUND: Allergy, the most frequent immune disorder affecting 30% of the world's population, is the consequence of immunoglobin E (IgE) sensitization to allergens. Among the genetic factors suspected to be involved in allergy, the HLA class-II genomic region is a strong candidate. OBJECTIVE: To assess the association between HLA class-II alleles and specific IgE (sIgE) sensitization to a large number of respiratory allergen molecules. METHODS: The analysis relied on 927 participants of the EGEA cohort, including 497 asthmatics. The study focuses on 26 aeroallergens recognized by sIgE in at least 5% of the study population (determined with the MEDALL chip with sIgE ≥ 0.3 ISU) and 23 imputed HLA class-II alleles. For each sIgE sensitization and HLA class-II allele, we fitted a logistic regression model accounting for familial dependence and adjusted for gender, age, and genetic principal components. p-values were corrected for multiple comparisons (False Discovery Rate). RESULTS: Most of the 19 statistically significant associations observed regard pollen allergens (mugwort Art v 1, olive tree Ole e 1, timothy grass Phl p 2, Phl p 5 and plantain Pla l 1), three were mold allergen (Alternaria Alt a 1), and a single one regards house dust mite allergen (Der p 7). No association was observed with pet allergens. The strongest associations were found with mugwort Art v 1 (OR = 5.42 (95%CI, 3.30; 8.88), 4.14 (2.65; 6.47), 3.16 (1.88; 5.31) with DQB1*05:01, DQA1*01:01 and DRB1*01:01, respectively). CONCLUSION: Our results support the important role of HLA class-II alleles as immune response genes predisposing their carriers for sensitization to various major pollen allergens.


Assuntos
Alérgenos , Hipersensibilidade , Alelos , Humanos , Hipersensibilidade/genética , Imunoglobulina E , Phleum
6.
Acta Biochim Pol ; 68(1): 15-22, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33720678

RESUMO

Timothy grass pollen is a source of potent allergens. Among them, Phl p 1 and Phl p 5 are thought to be the most important, as a majority of timothy grass-allergic individuals have IgE antibodies directed against these two allergens. The profilin from timothy grass (Phl p 12) has been registered as a minor allergen, with up to 35% of individuals in populations of grass pollen allergic patients showing IgE binding to Phl p 12. Profilins are primarily minor allergens and are known for a high likelihood of co-sensitization as well as cross-reactivity situations caused by their sequence and structure similarity. The crystal structure of Phl p 12.0101 was determined and it revealed that this allergen may form an unusual dimer not previously observed among any profilins. For example, the Phl p 12 dimer has a completely different geometry and interface when compared with the latex profilin (Hev b 8) dimer that has its crystal structure determined. The structure of Phl p 12.0101 is described in the context of allergenic sensitization and allergy diagnostics. Moreover, the structure of the Phl p 12.0101 dimer is discussed, taking into account the production of recombinant allergens and their storage.


Assuntos
Antígenos de Plantas/química , Phleum/química , Proteínas de Plantas/química , Pólen/química , Profilinas/química , Multimerização Proteica , Antígenos de Plantas/imunologia , Antígenos de Plantas/isolamento & purificação , Reações Cruzadas , Cristalização , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Phleum/imunologia , Proteínas de Plantas/imunologia , Pólen/imunologia , Profilinas/imunologia , Profilinas/isolamento & purificação , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Rinite Alérgica Sazonal/imunologia , Solventes/química
7.
Carbohydr Polym ; 255: 117384, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436213

RESUMO

Prebiotics are known for their ability to modulate the composition of the human microbiome and mediate health-promoting benefits. Endo-levanases, which hydrolyze levan into short-chain FOS, could be used for the production of levan-based prebiotics. The novel endo-levanase (LevB2286) from Azotobacter chroococcum DSM 2286, combines an exceptionally high specific activity with advantageous hydrolytic properties. Starting from levan isolated from Timothy grass, LevB2286 produced FOS ranging from DP 2 - 8. In contrast to endo-levanases described in the literature, LevB2286 formed minor amounts of fructose and levanbiose, even with greatly extended incubation. The combined activity of LevB2286 and the levansucrase LevS1417 from Gluconobacter japonicus LMG 1417 led to a one-step synthesis of levan-type FOS from sucrose. 387.4 ± 17.3 g L-1 FOS were produced within 48 h by the production strategy based on crude cell extract of recombinant Escherichia coli expressing levS1417 and levB2286 simultaneously.


Assuntos
Azotobacter/enzimologia , Proteínas de Bactérias/metabolismo , Gluconobacter/enzimologia , Glicosídeo Hidrolases/metabolismo , Hexosiltransferases/metabolismo , Oligossacarídeos/biossíntese , Prebióticos/análise , Azotobacter/genética , Proteínas de Bactérias/genética , Dissacarídeos/química , Dissacarídeos/metabolismo , Escherichia coli/enzimologia , Escherichia coli/genética , Frutanos/química , Frutanos/metabolismo , Frutose/química , Frutose/metabolismo , Expressão Gênica , Gluconobacter/genética , Glicosídeo Hidrolases/genética , Hexosiltransferases/genética , Humanos , Hidrólise , Oligossacarídeos/química , Phleum/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sacarose/química , Sacarose/metabolismo
8.
J Allergy Clin Immunol ; 147(2): 663-676, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33160969

RESUMO

BACKGROUND: Allergen-specific immunotherapy is a disease-modifying treatment that induces long-term T-cell tolerance. OBJECTIVE: We sought to evaluate the role of circulating CXCR5+PD-1+ T follicular helper (cTFH) and T follicular regulatory (TFR) cells following grass pollen subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) and the accompanying changes in their chromatin landscape. METHODS: Phenotype and function of cTFH cells were initially evaluated in the grass pollen-allergic (GPA) group (n = 28) and nonatopic healthy controls (NAC, n = 13) by mathematical algorithms developed to manage high-dimensional data and cell culture, respectively. cTFH and TFR cells were further enumerated in NAC (n = 12), GPA (n = 14), SCIT- (n = 10), and SLIT- (n = 8) treated groups. Chromatin accessibility in cTFH and TFR cells was assessed by assay for transposase-accessible chromatin sequencing (ATAC-seq) to investigate epigenetic mechanisms underlying the differences between NAC, GPA, SCIT, and SLIT groups. RESULTS: cTFH cells were shown to be distinct from TH2- and TH2A-cell subsets, capable of secreting IL-4 and IL-21. Both cytokines synergistically promoted B-cell class switching to IgE and plasma cell differentiation. Grass pollen allergen induced cTFH-cell proliferation in the GPA group but not in the NAC group (P < .05). cTFH cells were higher in the GPA group compared with the NAC group and were lower in the SCIT and SLIT groups (P < .01). Time-dependent induction of IL-4, IL-21, and IL-6 was observed in nasal mucosa following intranasal allergen challenge in the GPA group but not in SCIT and SLIT groups. TFR and IL-10+ cTFH cells were induced in SCIT and SLIT groups (all, P < .01). ATAC-seq analyses revealed differentially accessible chromatin regions in all groups. CONCLUSIONS: For the first time, we showed dysregulation of cTFH cells in the GPA group compared to NAC, SCIT, and SLIT groups and induction of TFR and IL-10+ cTFH cells following SCIT and SLIT. Changes in the chromatin landscape were observed following allergen-specific immunotherapy in cTFH and TFR cells.


Assuntos
Cromatina , Tolerância Imunológica/imunologia , Rinite Alérgica Sazonal/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Dessensibilização Imunológica/métodos , Feminino , Humanos , Injeções Subcutâneas , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Phleum/imunologia , Estudo de Prova de Conceito , Rinite Alérgica Sazonal/prevenção & controle , Imunoterapia Sublingual/métodos , Subpopulações de Linfócitos T/imunologia
10.
Eur J Immunol ; 51(1): 191-196, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32648940

RESUMO

Interleukin-31 (IL-31) is a Th2 cell-derived cytokine that has been closely linked to pruritic skin inflammation. More recently, enhanced IL-31 serum levels have also been observed in patients with allergic rhinitis and allergic asthma. Therefore, the main aim of this study was to unravel the contribution of IL-31 to allergen-induced lung inflammation. We analyzed lung inflammation in response to the timothy grass (Phleum pratense) pollen allergen Phl p 5 in C57BL/6 wild-type (wt) mice, IL-31 transgenic (IL-31tg) mice, and IL-31 receptor alpha-deficient animals (IL-31RA-/- ). IL-31 and IL-31RA levels were monitored by qRT-PCR. Cellular infiltrate in bronchoalveolar lavage fluid (BALF) and lung tissue inflammation, mucus production as well as epithelial thickness were measured by flow cytometry and histomorphology. While allergen challenge induced IL-31RA expression in lung tissue of wt and IL-31tg mice, high IL-31 expression was exclusively observed in lung tissue of IL-31tg mice. Upon Phl p 5 challenge, IL-31tg mice showed reduced numbers of leukocytes and eosinophils in BALF and lung tissue as well as diminished mucin expression and less pronounced epithelial thickening compared to IL-31RA-/- or wt animals. These findings suggest that the IL-31/IL-31RA axis may regulate local, allergen-induced inflammation in the lungs.


Assuntos
Alérgenos/efeitos adversos , Alérgenos/imunologia , Interleucinas/imunologia , Proteínas de Plantas/efeitos adversos , Proteínas de Plantas/imunologia , Pneumonia/imunologia , Animais , Asma/etiologia , Asma/imunologia , Asma/prevenção & controle , Líquido da Lavagem Broncoalveolar/imunologia , Modelos Animais de Doenças , Eosinófilos/imunologia , Feminino , Interleucinas/genética , Leucócitos/imunologia , Pulmão/imunologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Phleum/efeitos adversos , Phleum/imunologia , Pneumonia/etiologia , Pneumonia/prevenção & controle , Pólen/efeitos adversos , Pólen/imunologia , Receptores de Interleucina/deficiência , Receptores de Interleucina/genética , Receptores de Interleucina/imunologia
11.
J Oleo Sci ; 69(11): 1367-1371, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33055447

RESUMO

In this study, bioactive lipid components such as fatty acid composition, tocopherol and total phenolics content and antioxidant activity of few wild plant seed extracts were determined. The oil contents of seed samples changed between 3.75 g/100 g (Onobrychis viciifolia Scop) and 17.94 g/100 g (Pimpinella saxifrage L.). While oleic acid contents of seed oils change between 10.4% (Trifolium repens) and 29.5% (Onobrychis viciifolia Scop), linoleic acid contents of oil samples varied from 16.3% (Onobrychis viciifolia Scop) and 64.2% (Trifolium repens) (p < 0.05). While α-tocopherol contents of oil samples change between 2.112 (Pimpinella saxifrage L.) and 228.279 mg/100 g (Trifolium pratense), É£-tocopherol contents ranged from 0.466 (Phleum pratense) to 67.128 mg/100 g (Onobrychis viciifolia Scop). Also, α-tocotrienol contents of Onobrychis viciifolia Scop and Phleum pratense were 30.815 and 23.787 mg/100 g, respectively. Results showed some differences in total phenol contents and antioxidant activity values of extracts depending on plant species. The present study indicates that this seed oils are rich in fatty acid and tocopherol.


Assuntos
Antioxidantes/análise , Fabaceae/química , Ácidos Graxos/análise , Phleum/química , Pimpinella/química , Óleos Vegetais/química , Sementes/química , Tocoferóis/análise , Trifolium/química , Ácido Oleico/análise
12.
Allergy Asthma Proc ; 41(5): 357-362, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32867890

RESUMO

Background: The European Academy of Allergy and Clinical Immunology guidelines, strongly recommended allergen immunotherapy (AIT) as an effective treatment to achieve long-term clinical benefits and to modify the natural history of allergic diseases. Sublingual immunotherapy (SLIT) offers the possibility of home administration, which improves patient comfort and compliance. Objective: The primary outcome of this study was to assess the change in nasal reactivity after grass-pollen AIT treatment. Methods: This was a monocentric, prospective, observational study conducted in Rome from September 2016 to June 2018, in the Pediatric Department of Policlinico Umberto I. We enrolled children, ages between 6 and 12 years, with persistent allergic rhinitis (AR), sensitized to grass pollen. At the first visit (V0, September 2016), one group received the first dose of oral immunotherapy for grass-pollen spray buccal and the other group continued only standard therapy. All the patients had nasal specific immunoglobulin I (IgE) assay (Phl p1, Phl p5), active anterior rhinomanometry with a nasal provocation test (NPT), and spirometry. The patients attended two follow-up visits, in May 2017 (V1) and May 2018 (V2), with the same examinations as at V0. Results: During the treatment, we observed, in the treated group, a significant increase in the mean nasal flow compared with untreated children (p < 0.001). In the AIT group, we found an improvement of nasal function and only 21.05% of all the children in the active group with a positive NPT result at V2. In the control group, we found, at V2, a worsening of nasal function, with 89.47% of the children with a positive NPT result. Furthermore, we found a significant reduction of nasal specific IgE levels at the end of the observation period in the treated group. Conclusion: Analysis of our data provided evidence for a clinical effect of SLIT in inducing clinical changes and allergen tolerance in children with AR.


Assuntos
Alérgenos/imunologia , Imunoglobulina E/metabolismo , Cavidade Nasal/imunologia , Proteínas de Plantas/imunologia , Imunoterapia Sublingual/métodos , Criança , Feminino , Humanos , Tolerância Imunológica , Itália , Masculino , Testes de Provocação Nasal , Phleum/imunologia , Pólen/imunologia , Estudos Prospectivos , Rinite Alérgica , Rinomanometria
13.
J Dairy Sci ; 103(9): 8062-8073, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32600773

RESUMO

Tall fescue might be an alternative to timothy in northeastern North America because of its tolerance of recurring drought periods and its good summer regrowth, but is not always considered as an option in dairy rations because of its possible lack of palatability. The objective of this study was to evaluate the effects on the performance of lactating dairy cows of (1) replacing timothy silage by tall fescue silage, offered as sole forage in the diet or in combination with alfalfa silage, and (2) feeding tall fescue as silage (35% dry matter, DM) or haylage (55% DM). Experimental diets with a forage-to-concentrate ratio of 70:30 were (1) 100% timothy silage (TS); (2) 100% tall fescue silage (TFS); (3) 55:45 timothy:alfalfa silages (TS + AS); (4) 55:45 tall fescue:alfalfa silages (TFS + AS); and (5) 100% tall fescue haylage (TFH). Fifteen Holstein cows in mid-lactation (5 fitted with a rumen fistula) were randomly assigned to treatments in a triple 5 × 5 Latin square design with treatment periods of 21 d. Preplanned contrasts were timothy versus tall fescue silages, sole grass species versus grass-alfalfa, interaction between sole grass species and grass-alfalfa, and TFS versus TFH. Grass species did not affect dry matter intake (DMI) or milk yield and fat concentration. Milk protein concentration was not affected by grass species when offered in combination with alfalfa, but it was higher with the TS diet than the TFS diet when offered as sole forages. Adding alfalfa to either tall fescue or timothy silage resulted in greater DMI and milk yield, but lower milk fat concentration, than when the grass silages were the sole forage in the diet. The molar proportion of propionate in the rumen was greater when cows were fed diets with tall fescue silage compared with timothy silage, which resulted in a lower acetate-to-propionate ratio. Milk fat concentrations of fatty acids from microbial origin, namely branched-chain fatty acids, were greater when grass silage, and especially timothy silage, were fed as sole forages rather than with alfalfa silage. Feeding TFH rather than TFS caused a decrease in DMI and tended to lower milk protein concentration, but did not affect milk yield. A more fibrolytic fermentation profile was observed in rumen of cows fed TFH compared with TFS, as indicated by the increase in the molar proportion of acetate and the higher acetate-to-propionate ratio in rumen fluid, and a concomitant increase in branched-chain fatty acid concentration in milk fat. Tall fescue as silage or haylage is a valuable alternative to timothy silage for lactating dairy cows.


Assuntos
Dieta/veterinária , Festuca/metabolismo , Medicago sativa/metabolismo , Phleum/metabolismo , Ração Animal/análise , Ração Animal/normas , Animais , Bovinos , Digestão , Ácidos Graxos/metabolismo , Feminino , Fermentação , Lactação/fisiologia , Leite/química , Distribuição Aleatória , Rúmen/metabolismo , Silagem/análise
14.
Allergy Asthma Proc ; 41(3): 183-191, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32375962

RESUMO

Background: The presence of immunoglobulin E (IgE), which cross-reacts with allergen components, such as profilins, polcalcins, and cross-reacting carbohydrate determinants (CCD), creates a problem when selecting patients for allergen immunotherapy by using conventional methods. The aim of this study was to evaluate the prevalence of sensitization to profilins, polcalcins, and CCDs in patients with seasonal pollen allergic rhinitis. Methods: The study was performed on a group of 112 patients with seasonal pollen allergic rhinitis, ages 14 to 55 years, with sensitization to at least one seasonal allergen (IgE > 0.7 kUA/L). The presence of IgE sensitization to recombinant (r) Bet v 2, rPhl p 12, rBet v 4, rPhl p 7, and CCDs, in addition to rBet v 1, rPhl p 1, rPhl p 5, was evaluated by using a multiparameter immunoblot. Results: Among the studied patients, 64.3, 80.4, and 41.1% were sensitized to birch, timothy grass, and mugwort pollen, respectively. Sensitization to profilins rBet v 2/Phl p 12 was demonstrated in 28.6%, to polcalcins Bet v 4/Phl p 7 in 8.9%, and to CCDs in 25%. In 29.3%, serum IgE reactivity to any of the cross-reactive components could be demonstrated. Serum IgE reactivity to rBet v 2 was always accompanied by IgE reactivity to rPhl p 12, and IgE reactivity to rBet v 4 was always accompanied by IgE reactivity to rPhl p 7. Among the patients with pollinosis co-sensitized to at least two allergen sources according to extract-based diagnosis, possible false-positive results due to sensitization to cross-reactive components were detected in 17.9%. Conclusion: Evaluation of sensitization to cross-reacting components may be useful in evaluation of patients with pollen allergy who are being assessed for allergen immunotherapy to optimize the constitution of their immunotherapy vaccines.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Proteínas de Ligação ao Cálcio/imunologia , Imunoglobulina E/imunologia , Pólen/imunologia , Profilinas/imunologia , Rinite Alérgica Sazonal/imunologia , Adolescente , Adulto , Artemisia/imunologia , Betula/imunologia , Reações Cruzadas/imunologia , Dessensibilização Imunológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Phleum/imunologia , Polônia , Rinite Alérgica Sazonal/terapia , Adulto Jovem
15.
PLoS One ; 15(4): e0231344, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324770

RESUMO

BACKGROUND: Cross-reactive carbohydrate determinant (CCD) structures found in plant and insect glycoproteins are commonly recognized by IgE antibodies as epitopes that can lead to extensive cross-reactivity and obscure in vitro diagnostic (IVD) serology results. With the introduction of component resolved diagnosis (CRD), recombinant non-glycosylated components have been utilized to mitigate the risk of CCD-specific IgE (sIgE) detection. However, a recent study has shown that CCD-sIgE may bind directly to the cellulose solid phase matrix used in certain in vitro diagnostic assays, eliminating the advantage of CRD over traditional extract-based testing. The aim of this study is to further investigate the prevalence of CCD-sIgE interference on a commonly-used in vitro sIgE automated platform which employs a cellulose-based matrix to immobilize CCD-free recombinant components. METHODS: Sera from patients sensitized to peanut, silver birch, and/or timothy grass were analyzed for CCD-sIgE reactivity on ImmunoCAP/Phadia and NOVEOS autoanalyzers against the MUXF3 carbohydrate component. Positive CCD-sIgE sera were further analyzed against non-glycosylated recombinant components bound to the ImmunoCAP solid phase in the absence and presence of a soluble CCD inhibitor. For comparison, sera were then analyzed on NOVEOS, a non-cellulose based automated sIgE assay. RESULTS: Sera from 35% of the sensitized population tested in this study were positive (≥0.35 kU/L) for CCD-sIgE. Of those positives, 17% resulted in CCD-sIgE-positive (false positive) results on ImmunoCAP using non-glycosylated allergosorbents that were negative on NOVEOS. Sera producing false-positive results on ImmunoCAP had varying levels of CCD-sIgE from 0.67 kU/L to 36.52 kU/L. The incidence of CCD interference was predominantly delimited to low-positive IgE results (0.35 kUA/L- 3.00 kUA/L). CONCLUSION: Falsely elevated diagnostic allergen-sIgE results can commonly occur due to the presence of CCD-sIgE using assays that employ a carbohydrate matrix-based allergosorbent. Even the use of non-glycosylated recombinant allergenic components coupled to cellulose matrices do not reduce their risk of detection. The risk of CCD interference that compromises quantitative IgE results can be mitigated by the addition of a soluble CCD inhibitor to positive CCD-sIgE containing sera or by alternatively using a non-cellulose based sIgE assay, such as the NOVEOS assay.


Assuntos
Alérgenos/imunologia , Celulose/imunologia , Imunoglobulina E/imunologia , Alérgenos/genética , Alérgenos/metabolismo , Arachis/imunologia , Betula/imunologia , Reações Cruzadas , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/patologia , Imunoglobulina E/sangue , Phleum/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia
16.
J Allergy Clin Immunol Pract ; 8(4): 1387-1393.e2, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31954191

RESUMO

BACKGROUND: Timothy grass sublingual immunotherapy (SLIT) tablets are indicated for children with allergic rhinitis with or without conjunctivitis. OBJECTIVE: To use pooled analyses to assess the short- and long-term tolerability and safety of timothy grass SLIT-tablet in children. METHODS: Data from 9 double-blinded, randomized European or North American trials that included children with allergic rhinitis with or without conjunctivitis treated up to 3 years with once-daily timothy grass SLIT-tablet or placebo were pooled. RESULTS: In all, 1818 (timothy grass SLIT-tablet, n = 923; placebo, n = 895) subjects were included in the analysis. The frequency of treatment-emergent adverse events (AEs) was 86% in the SLIT-tablet group and 83% in the placebo group, and the frequency of treatment-related AEs (TRAEs) was 59% and 23%, respectively. Most (98%) TRAEs were mild to moderate in severity. The 2 most common TRAEs with SLIT-tablet were oral pruritus (33%) and throat irritation (19%), which had a median onset of 1 day and recurrence of 14.5 and 5 days, respectively. In all, 8% of subjects in the SLIT-tablet group and 2% in the placebo group discontinued because of AEs. There were 7 serious AEs assessed as related to SLIT-tablet, 1 systemic allergic reaction (severe with a drop in blood pressure), 3 epinephrine administrations, no eosinophilic esophagitis events, and no serious airway obstructions. The safety profile was similar in subjects across geographic regions and with and without asthma. CONCLUSIONS: Pooled data indicate that short- and long-term timothy grass SLIT-tablet is well tolerated in children, regardless of geographic region. AEs were generally local, mild, and transient allergic reactions.


Assuntos
Asma , Rinite Alérgica , Imunoterapia Sublingual , Alérgenos , Criança , Humanos , Phleum , Poaceae , Comprimidos , Resultado do Tratamento
18.
J Allergy Clin Immunol ; 145(4): 1174-1181.e6, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31954777

RESUMO

BACKGROUND: Grass pollen allergy is one of the most common allergies worldwide. OBJECTIVE: The aim of this study was to evaluate the usefulness of grass pollen allergen molecules for prediction of grass pollen allergy during childhood and up to adolescence. METHOD: Questionnaire data and sera obtained from the study subjects at the ages of 4, 8, and 16 years from the population-based Barn/Children Allergy Milieu Stockholm Epidemiology birth cohort were used. Sera from 763 representative subjects with serum samples available at all 3 ages were analyzed for IgE reactivity to 8 Phleum pratense (Phl p) allergens (MeDALL [Mechanisms for the Development of Allergies] chip) and to timothy grass extract (ImmunoCAP). Allergic rhinitis to grass pollen (ARg) was defined as upper airway symptoms during grass pollen exposure. RESULTS: The prevalence of sensitization to any Phl p molecule was higher compared with that to timothy extract at all 3 ages: at the age of 4 years, 9.7% versus 6.8%; at the age of 8 years, 28.4% versus 15.3%; and at the age of 16 years, 37.1% versus 27.1%. General estimating equations analyses revealed that among children sensitized at the age of 4 years, the overall odds ratio (OR) of later ARg (up to 16 years) was increased only for IgE reactivity to Phl p 1 (OR = 4.9) and natural Phl p 4 (OR = 6.9). The likelihood of later symptoms increased with the number of allergen molecules; at the age of 4 years, 2 or more molecules predicted ARg to 78% and 3 or more molecules predicted ARg to 95%. A positive test result for timothy extract predicted ARg to 70%. CONCLUSIONS: Natural Phl p 4 is a hitherto unrecognized early indicator of grass pollen allergy, in addition to Phl p 1. To identify grass pollen sensitization and predict later ARg, allergen molecules are of added value to timothy extract alone and may help clinicians improve prediction of grass pollen allergy.


Assuntos
Alérgenos/imunologia , Imunoglobulina E/metabolismo , Extratos Vegetais/imunologia , Proteínas de Plantas/imunologia , Rinite Alérgica/diagnóstico , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Humanos , Imunização , Testes Imunológicos , Phleum , Pólen/imunologia , Prevalência , Prognóstico , Rinite Alérgica/epidemiologia , Rinite Alérgica/imunologia , Testes Cutâneos , Inquéritos e Questionários , Suécia/epidemiologia
19.
Animal ; 14(4): 753-762, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31658932

RESUMO

This study investigated the effect of forage type (grass or red clover) and harvesting time (primary growth or regrowth) of silage on energy and N utilisation by sheep fed at maintenance level. Specifically, the assumption of constant loss of energy of digestible organic matter from energy losses in urine and CH4 applied in evaluation of silage metabolisable energy (ME) was investigated. Urinary excretion of high-energy phenolic compounds related to solubilisation of lignin was assumed to affect urinary energy (UE) losses from sheep fed highly digestible grass silage (GS). A total of 25 primary growth and regrowth silages of timothy (Phleum pratense) and meadow fescue (Festuca pratensis) grass mixtures and red clover (Trifolium pratense) samples collected in digestibility trials with sheep, including faecal and urine samples, were used for energy and N determinations. Urinary concentration of monophenolic compounds and CH4 emissions in vitro were also analysed. Daily faecal N output, CH4 yield (MJ/kg DM intake), proportion of CH4 energy in digestible energy (DE) and proportion of UE in DE were greater (P ≤ 0.03) in sheep fed red clover silage (RCS) than GS. Furthermore, less (P = 0.01) energy was lost as UE of DE in sheep fed primary growth GS compared with the other treatments. The relationship between UE and silage N intake or urinary N output for both silage types (i.e. grass v. red clover) was strong, but the fit of the regressions was better for GS than RCS. The CH4/DE ratio decreased (P < 0.05) and the UE/DE ratio increased (P < 0.05) with increasing organic matter digestibility in RCS. These relationships were not significant (P < 0.05) for the GS diets. The regression coefficient was higher (P < 0.05) for GS than RCS when regressing ME concentration on digestible organic matter. The results of this study imply that ME/DE ratio is not constant across first-cut GS of different maturities. The ME production response may be smaller from highly digestible first-cut GS but could not be clearly related to urinary excretion of monophenols derived from solubilisation of lignin. Furthermore, energy lost in urine was not clearly defined for RCS and was much more predictable for GS from silage N concentration.


Assuntos
Metabolismo Energético , Nitrogênio/metabolismo , Poaceae , Ovinos/fisiologia , Silagem/análise , Trifolium , Animais , Parede Celular/química , Dieta/veterinária , Digestão , Fezes/química , Feminino , Festuca , Hidroxibenzoatos/metabolismo , Hidroxibenzoatos/urina , Lignina/metabolismo , Metano/análise , Metano/metabolismo , Leite/metabolismo , Nitrogênio/urina , Phleum
20.
J. investig. allergol. clin. immunol ; 30(5): 334-339, 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-200761

RESUMO

BACKGROUND: The association between pollen counts and allergen levels in the air is controversial. OBJECTIVES: The aims of the study were to quantify total and major allergen levels of Phleum pratense and Olea europaea and to analyze their correlation with grass and olive pollen counts and the number of asthma attacks attended at Complejo Hospitalario Universitario, Cáceres, Spain. MATERIAL AND METHODS: A volumetric air sampler and a Burkard spore trap were used for pollen and aeroallergen collection during April- June 2011. Filters were extracted, and major allergens were quantified using enzyme-linked immunosorbent assay. RESULTS: May was the main grass pollination period, with a maximum peak of 1362 grains/m3 (May 13). The main pollination period for olive was April 30-May 20, with a maximum peak of 851 grains/m3 (May 11). A moderate correlation was observed between asthma exacerbations and grass pollen counts or Phleum total allergen levels; this became stronger when a 3-day offset was introduced. A significant association was observed between asthma exacerbations and total olive allergen or olive pollen grain levels when a 1-day offset was introduced. The maximum correlation (moderate-high) was observed 4 days and 6 days away from the maximum olive pollen peak and the maximum Ole e 1 peak level, respectively. CONCLUSIONS: This study reveals a significant correlation between grass and olive pollination and an increase in the number of visits to the emergency room for asthma attacks. The aerobiological pattern of allergen levels in the air is similar to that of pollen counts during the grass and olive pollination periods


ANTECEDENTES: La relación entre los niveles de pólenes en el aire y los niveles de alérgenos es controvertida. OBJETIVOS: El objetivo de este estudio fue cuantificar los niveles de alérgenos principales y totales de Phleum pratense y Olea europaea, y analizar su relación con los niveles de pólenes y el número de crisis asmáticas atendidas en el Complejo Hospitalario de Cáceres, España. MATERIAL Y MÉTODOS: Se captaron pólenes y aeroalérgenos durante Abril-Junio de 2011, utilizando un colector de aire volumétrico y una trampa Burkard. Se extrajeron los alérgenos de los filtros y se cuantificaron mediante ELISA. RESULTADOS: Mayo fue el periodo de mayor polinización, (13 de Mayo, pico máximo de 1.362 granos de polen de gramíneas/m3). El mayor periodo de polinización del olivo fue del 30 de Abril al 20 de Mayo, (11 de Mayo, pico máximo: 851 granos de polen de olivo/m3). Se observó una correlación moderada entre los niveles de polen o alérgenos totales y exacerbaciones de asma, que aumentó al introducir un desfase de 3 días (Phleum), y de 1 día (olivo). La máxima correlación se observó a los 4 y 6 días del pico máximo de polen y de Ole e 1, respectivamente. CONCLUSIONES: Este estudio muestra una correlación significativa entre la polinización de gramíneas y olivo y el aumento del número de visitas a urgencias debidas a crisis asmáticas. Los patrones aerobiológicos de los niveles de alérgenos en el aire son comparables a los recuentos de pólenes durante los periodos de polinización de gramíneas y olivo


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Pastagens/efeitos adversos , Asma/imunologia , Pólen/efeitos adversos , Alérgenos/isolamento & purificação , Olea/efeitos adversos , Phleum/efeitos adversos , Espanha/epidemiologia , Técnicas Imunológicas/métodos , Imunoquímica , Exposição Ambiental/análise , Polinização , Tratamento de Emergência/estatística & dados numéricos , Asma/epidemiologia
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