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There is a balance between DM yield and feed value when choosing types of grasses on a farm depending on the acreages of farmland and types of ruminants to be fed. Therefore, optimisation of the harvest strategy for grass silage is important for profitable dairy farming. Tall fescue has high DM yield and can replace traditional grasses, such as timothy, in Northern Europe in a changing climate as it has been shown to be more drought tolerant. As differences in climate responses previously have been related to differences in cell wall structure between grass species and, consequently, in digestibility, it is highly relevant to compare these species at similar maturity stages and to investigate if a very early harvest date will diminish potential differences between the species. This study evaluated the effects of harvest date and forage species on the concentration of hydroxycinnamic acids in silages and its relationship to feed efficiency of dairy cows. Tall fescue and timothy were harvested at very early date on May 25 or at early date on May 31 in the spring growth cycle. Forty lactating dairy cows were used in a block design. Cows received 1 of 4 treatments: (1) tall fescue harvested at very early date, (2) timothy harvested at very early date, (3) tall fescue harvested at early date, and (4) timothy harvested at early date. Diets were formulated to have the same forage-to-concentrate ratio (49:51 on DM basis). Tall fescue silages showed greater concentrations of DM, ash, and CP than timothy silages. Grasses harvested at early date showed greater concentrations of NDF, ADL, and cell wall than grasses harvested at very early date. Tall fescue silages showed greater concentration of p-coumaric acid and lower in vitro organic matter digestibility (IVOMD) compared to timothy silages. Milk production and composition were not affected by treatments but cows fed tall fescue-based diets showed lower milk protein yield and greater milk urea nitrogen than when timothy-based diets were fed. Furthermore, cows receiving timothy-based diets showed greater feed efficiency compared to cows receiving tall fescue-based diets. Thus, the lower concentration of p-coumaric acid and the higher IVOMD was associated with greater feed efficiency of cows fed timothy-based diets compared to tall fescue-based diets.
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Alimentación Animal , Pared Celular , Dieta , Ensilaje , Animales , Bovinos/fisiología , Femenino , Ensilaje/análisis , Alimentación Animal/análisis , Dieta/veterinaria , Phleum , Industria Lechera/métodos , Lactancia , Leche/química , Leche/metabolismo , Festuca , Poaceae , Fenómenos Fisiológicos Nutricionales de los Animales , Digestión/fisiologíaRESUMEN
BACKGROUND: The fluctuation in concentrations of airborne allergens frequently presents a challenge to assessing the efficacy of allergen immunotherapy (AIT) in 'field' studies. Allergen exposure chambers (AECs) are specialized medical installations developed to expose individuals to allergens at defined and consistent concentrations under a controlled environment. The aim of the study was to validate the provocation test with timothy grass pollen as well as to assess its safety in the AEC in patients with allergic rhinitis. METHODS: In the ALLEC® AEC, varying concentrations of timothy grass pollen were dispersed. Allergic symptoms were measured by total nasal symptom score (TNSS), acoustic rhinometry, peak nasal inspiratory flow (PNIF) and nasal discharge volume. Lung function, assessed through peak expiratory flow rate (PEFR) and forced expiratory volume in the first second (FEV1), was used to evaluate safety. RESULTS: The consistency of the test was proved by the stability of environmental conditions, including temperature, humidity and CO2 levels, as well as constant concentrations of grass pollen at predetermined levels ranging from 1000 to 10,000 particles per cubic meter (p/m3). Allergic individuals developed symptoms at concentrations of 3000 p/m3 and above, across all measured endpoints. Lung function was not affected throughout all the challenges. The reproducibility of symptoms was confirmed throughout the tests. The concentration of 8000 p/m3 together with a challenge duration of 120 min was found to be optimal. CONCLUSION: The study demonstrates that the ALLEC® grass pollen exposure chamber provides a reliable and safe method for inducing repeatable symptoms in patients with allergic rhinitis. This approach can be effectively applied for allergy diagnostics and clinical endpoint determination during AIT.
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Alérgenos , Phleum , Polen , Rinitis Alérgica Estacional , Humanos , Phleum/inmunología , Masculino , Femenino , Polen/inmunología , Adulto , Alérgenos/inmunología , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica Estacional/terapia , Rinitis Alérgica Estacional/fisiopatología , Rinitis Alérgica/diagnóstico , Rinitis Alérgica/terapia , Rinitis Alérgica/inmunología , Persona de Mediana Edad , Cámaras de Exposición Atmosférica , Adulto Joven , Reproducibilidad de los Resultados , Pruebas de Provocación Nasal , Pruebas de Función RespiratoriaRESUMEN
Type of feed is an important consideration in herbivore colony management, yet limited studies report on the effects of diet on common conditions such as urolithiasis in guinea pigs. Urolithiasis is a well-documented cause of lower urinary tract disease in guinea pigs, with calcium carbonate uroliths reported as the predominant calculi formed in the guinea pig urinary tract. A calcium-rich diet has been suggested as a risk factor for of urolithiasis, with numerous commercially available guinea pig diets formulated for adults avoiding ingredients that are higher in calcium. Due to the high incidence of urolithiasis in our strain 13/N guinea pig colony, we conducted a prospective control study following the implementation of dietary changes aimed at improving overall urinary tract health and reducing risk factors for urolithiasis, thus improving colony welfare. A control group was kept on the original ad libitum alfalfa hay-based pellet diet with restricted loose timothy hay (control diet, 14 juveniles and 24 adults). An experimental group was placed on a portioned, 1 oz daily, timothy hay-based pellet diet with ad libitum loose timothy hay (experimental diet, 21 juveniles and 23 adults). Juveniles and adults were followed for a total of 14 and 26 wk, respectively. Longitudinal blood and urine samples were collected to evaluate blood chemistry and urinary parameters, along with weight and body condition scores to assess general health. Overall, dietary changes did not improve parameters associated with improved urinary tract health or reduced risk of urolithiasis; feeding strategy was not found to meaningfully affect calcium crystalluria, urine protein, urine specific gravity, or renal values. These data support alfalfa hay-based pellet or timothy hay-based pellet, when fed with loose timothy hay, as viable options and suggest that practices aimed at reducing dietary calcium by reducing pelleted diet portions are insufficient to mitigate risk factors for urolithiasis in guinea pigs.
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Alimentación Animal , Dieta , Animales , Cobayas , Alimentación Animal/análisis , Masculino , Dieta/veterinaria , Femenino , Phleum , Destete , Urolitiasis/prevención & control , Urolitiasis/veterinaria , Urolitiasis/etiología , Estudios Prospectivos , Enfermedades de los Roedores/prevención & control , Sistema UrinarioRESUMEN
The sustainable production of perennial grasses in Northern Norway is at risk due to the ongoing climate change. The predicted increase in temperatures and variable weather patterns are further expected to create challenges for winter survival of timothy (Phleum pratense L.). Knowledge about the molecular mechanisms underlying freezing tolerance is crucial for developing robust cultivars. The current study is aimed at identifying genes involved in freezing stress response of timothy and studying gene expression differentiation due to field selection in contrasting environments using RNAseq. Four timothy cultivars were field tested for three years in Tromsø and Vesterålen, in Northern Norway. The surviving material from the field tests, along with plants raised from the original seed lots, were subjected to freezing tests. LT50 values varied across cultivars and materials. Many genes coding for transcription factors and proteins known to play an important role in freezing tolerance, like dehydrins, c-repeat binding factors, and late embryogenesis abundant proteins were upregulated with decreasing temperatures. Moreover, genes associated with glycolysis/gluconeogenesis, TCA cycle, glutathione metabolism, proteasome pathways and genes encoding autophagy-related proteins, plasma membrane-associated proteins, sugar and amino acid transporters had elevated expression in field survivors compared to plants raised from the original material. The lower freezing stress tolerance of field survivors despite the elevated expression of several stress-responsive genes might be due to a combination of selection in the field and the age effect. Furthermore, differences in freezing stress response between northern and southern adapted cultivars and surviving material from two field trial locations are discussed.
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Phleum , Proteínas de Plantas , Phleum/genética , Phleum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Congelación , Frío , Expresión GénicaRESUMEN
BACKGROUND: Nasal epithelial cells are important regulators of barrier function and immune signaling; however, in allergic rhinitis (AR) these functions can be disrupted by inflammatory mediators. We aimed to better discern AR disease mechanisms using transcriptome data from nasal brushing samples from individuals with and without AR. METHODS: Data were drawn from a feasibility study of individuals with and without AR to Timothy grass and from a clinical trial evaluating 16 weeks of treatment with the following: dupilumab, a monoclonal antibody that binds interleukin (IL)-4Rα and inhibits type 2 inflammation by blocking signaling of both IL-4/IL-13; subcutaneous immunotherapy with Timothy grass (SCIT), which inhibits allergic responses through pleiotropic effects; SCIT + dupilumab; or placebo. Using nasal brushing samples from these studies, we defined distinct gene signatures in nasal tissue of AR disease and after nasal allergen challenge (NAC) and assessed how these signatures were modulated by study drug(s). RESULTS: Treatment with dupilumab (normalized enrichment score [NES] = -1.73, p = .002) or SCIT + dupilumab (NES = -2.55, p < .001), but not SCIT alone (NES = +1.16, p = .107), significantly repressed the AR disease signature. Dupilumab (NES = -2.55, p < .001), SCIT (NES = -2.99, p < .001), and SCIT + dupilumab (NES = -3.15, p < .001) all repressed the NAC gene signature. CONCLUSION: These results demonstrate type 2 inflammation is an important contributor to the pathophysiology of AR disease and that inhibition of the type 2 pathway with dupilumab may normalize nasal tissue gene expression.
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Anticuerpos Monoclonales Humanizados , Rinitis Alérgica , Transcriptoma , Humanos , Rinitis Alérgica/genética , Rinitis Alérgica/terapia , Alérgenos , Inflamación , Phleum , Interleucina-13/metabolismo , InmunoterapiaRESUMEN
IgE sensitization profiles to single birch allergens in birch-sensitized patients differ among European countries. The aim of this study was to determine the distribution of specific IgE antibodies to major and minor birch pollen allergens in a population of allergic Norwegian individuals by using a birch allergic blood donor population as a surrogate sample. Sixty blood donors were recruited and sampled based on birch allergy symptoms such as rhinitis, rhinoconjunctivitis and/or mild asthma in previous seasons. All sera were collected before start of the pollen season and tested using a line blot assay (Euroimmun AG, Lübeck, Germany) for IgE to birch and timothy pollen. Both extracts, single allergens, and cross-reacting carbohydrate determinants (CCD) were analysed. Only donors with specific IgE to birch and/or timothy grass were further evaluated. Specific IgE to birch pollen extract was found in 52 sera, and sensitization to timothy grass in 40 sera. Specific IgE to Bet v 1 was predominant in contrast to Bet v 4 which was absent. However, sensitization to the minor allergens Bet v 2 and 6 was always found together with high levels of IgE to Bet v 1. Subjects sensitized to the profilin Bet v 2 from birch were also sensitized to Phl p 12 from timothy grass. In conclusion, there was predominantly Bet v 1 sensitization in this cohort and low sensitization to minor allergens and cross-reactive allergens (Bet v 2, Bet v 4, Phl p 7 and Phl p 12).
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Betula , Hipersensibilidad , Humanos , Phleum , Donantes de Sangre , Inmunoglobulina E , Hipersensibilidad/diagnóstico , Polen , Alérgenos , Reacciones CruzadasRESUMEN
BACKGROUND: Allergen immunotherapy (AIT) is a well-established disease-modifying therapy for allergic rhinitis, yet the fundamental mechanisms underlying its clinical effect remain inadequately understood. Gauging Response in Allergic Rhinitis to Sublingual and Subcutaneous Immunotherapy was a randomized, double-blind, placebo-controlled trial of individuals allergic to timothy grass who received 2 years of placebo (n = 30), subcutaneous immunotherapy (SCIT) (n = 27), or sublingual immunotherapy (SLIT) (n = 27) and were then followed for 1 additional year. OBJECTIVE: We used yearly biospecimens from the Gauging Response in Allergic Rhinitis to Sublingual and Subcutaneous Immunotherapy study to identify molecular mechanisms of response. METHODS: We used longitudinal transcriptomic profiling of nasal brush and PBMC samples after allergen provocation to uncover airway and systemic expression pathways mediating responsiveness to AIT. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01335139, EudraCT Number: 2010-023536-16. RESULTS: SCIT and SLIT demonstrated similar changes in gene module expression over time. In nasal samples, alterations included downregulation of pathways of mucus hypersecretion, leukocyte migration/activation, and endoplasmic reticulum stress (log2 fold changes -0.133 to -0.640, false discovery rates [FDRs] <0.05). We observed upregulation of modules related to epithelial development, junction formation, and lipid metabolism (log2 fold changes 0.104 to 0.393, FDRs <0.05). In PBMCs, modules related to cellular stress response and type 2 cytokine signaling were reduced by immunotherapy (log2 fold changes -0.611 to -0.828, FDRs <0.05). Expression of these modules was also significantly associated with both Total Nasal Symptom Score and peak nasal inspiratory flow, indicating important links between treatment, module expression, and allergen response. CONCLUSIONS: Our results identify specific molecular responses of the nasal airway impacting barrier function, leukocyte migration activation, and mucus secretion that are affected by both SCIT and SLIT, offering potential targets to guide novel strategies for AIT.
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Rinitis Alérgica , Inmunoterapia Sublingual , Humanos , Transcriptoma , Leucocitos Mononucleares , Polen , Alérgenos , Desensibilización Inmunológica/métodos , Inmunoterapia Sublingual/métodos , Phleum , Inyecciones Subcutáneas , Rinitis Alérgica/terapia , Rinitis Alérgica/tratamiento farmacológicoRESUMEN
Mitigating enteric methane (CH4) emissions is crucial as ruminants account for 5% of global greenhouse gas emissions. We hypothesised that less frequent harvesting, use of crops with lower WSC concentration, ensiling at low crop dry matter (DM) and extensive lactic acid fermentation would reduce in vitro CH4 production. Timothy (T), timothy + red clover mixture (T + RC) or perennial ryegrass (RG), cut either two or three times per season, was wilted to 22.5% or 37.5% DM and ensiled with or without formic acid-based additive. Silages were analysed for chemical composition and fermentation products. In vitro CH4 production was measured using an automated gas in vitro system. Methane production was, on average, 2.8 mL/g OM lower in the two-cut system than in the three-cut system (P < 0.001), and 1.9 mL/g OM lower in T than in RG (P < 0.001). Silage DM did not affect CH4 production (P = 0.235), but formic acid increased CH4 production by 1.2 mL/g OM compared to the untreated silage (P = 0.003). In conclusion, less frequent harvesting and extensive silage fermentation reduce in vitro CH4 production, while RG in comparison to T resulted in higher production of CH4.
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Poaceae , Ensilaje , Animales , Ensilaje/análisis , Fermentación , Metano/metabolismo , Pradera , Phleum , Dieta , Rumen/metabolismo , DigestiónRESUMEN
BACKGROUND: Allergic disease reflects specific inflammatory processes initiated by interaction between allergen and allergen-specific IgE. Specific immunotherapy (SIT) is an effective long-term treatment option, but the mechanisms by which SIT provides desensitization are not well understood. OBJECTIVE: Our aim was to characterize IgE sequences expressed by allergen-specific B cells over a 3-year longitudinal study of patients with aeroallergies who were undergoing SIT. METHODS: Allergen-specific IgE-expressing clones were identified by using combinatorial single-chain variable fragment libraries and tracked in PBMCs and nasal biopsy samples over a 3-year period with antibody gene repertoire sequencing. The characteristics of private IgE-expressing clones were compared with those of stereotyped or "public" IgE responses to the grass pollen allergen Phleum pratense (Phl p) 2. RESULT: Members of the same allergen-specific IgE lineages were observed in nasal biopsy samples and blood, and lineages detected at baseline persisted in blood and nasal biopsy samples after 3 years of SIT, including B cells that express IgE. Evidence of progressive class switch recombination to IgG subclasses was observed after 3 years of SIT. A common stereotyped Phl p 2-specific antibody heavy chain sequence was detected in multiple donors. The amino acid residues enriched in IgE-stereotyped sequences from seropositive donors were analyzed with machine learning and k-mer motif discovery. Stereotyped IgE sequences had lower overall rates of somatic hypermutation and antigen selection than did single-chain variable fragment-derived allergen-specific sequences or IgE sequences of unknown specificity. CONCLUSION: Longitudinal tracking of rare circulating and tissue-resident allergen-specific IgE+ clones demonstrates persistence of allergen-specific IgE+ clones, progressive class switch recombination to IgG subtypes, and distinct maturation of a stereotyped Phl p 2 clonotype.
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Anticuerpos de Cadena Única , Humanos , Anticuerpos de Cadena Única/genética , Estudios Longitudinales , Desensibilización Inmunológica , Alérgenos , Phleum , Inmunoglobulina E , Inmunoglobulina G , Evolución Clonal , Proteínas de Plantas , PoaceaeRESUMEN
Allergy and rhinovirus (RV) infections are major triggers for rhinitis and asthma, causing a socioeconomic burden. As RVs and allergens may act synergistically to promote airway inflammation, simultaneous treatment strategies for both causative agents would be innovative. We have previously identified the transmembrane glycoprotein intercellular adhesion molecule 1 (ICAM-1) as an anchor for antibody conjugates bispecific for ICAM-1 and Phleum pratense (Phl p) 2, a major grass pollen allergen, to block allergen transmigration through the epithelial barrier. Since ICAM-1 is a receptor for the major group RVs, we speculated that our bispecific antibody conjugates may protect against RV infection. Therefore, we created antibody conjugates bispecific for ICAM-1 and the major grass pollen allergen Phl p 5 and analyzed their capacity to affect allergen penetration and RV infection. Bispecific antibody conjugates significantly reduced the trans-epithelial migration of Phl p 5 and thus the basolateral Phl p 5 concentration and allergenic activity as determined by humanized rat basophilic leukemia cells and inhibited RV infection of cultured epithelial cells. A reduction in allergenic activity was obtained only through the prevention of allergen transmigration because the Phl p 5-specific IgG antibody did not block the allergen-IgE interaction. Our results indicate the potential of allergen/ICAM-1-specific antibody conjugates as a topical treatment strategy for allergy and RV infections.
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Alérgenos , Hipersensibilidad , Rhinovirus , Molécula 1 de Adhesión Intercelular , Inmunoglobulina E , Polen , Poaceae , Phleum , Proteínas de PlantasRESUMEN
BACKGROUND: Immunologic mechanism of action of allergoids remains poorly understood. Previous models of allergenicity and immunogenicity have yielded suboptimal knowledge of these immunotherapeutic vaccine products. Novel single-cell RNA sequencing technology offers a bridge to this gap in knowledge. OBJECTIVE: We sought to identify the underpinning tolerogenic molecular and cellular mechanisms of depigmented-polymerized Phleum pratense (Phl p) extract. METHODS: The molecular mechanisms underlying native Phl p, depigmented Phl p (DPG-Phl p), and depigmented-polymerized (DPG-POL-Phl p) allergoid were investigated by single-cell RNA sequencing. Allergen-specific TH2A, T follicular helper (Tfh), and IL-10+ regulatory B cells were quantified by flow cytometry in peripheral blood mononuclear cells from 16 grass pollen-allergic and 8 nonatopic control subjects. The ability of Phl p, DPG-Phl p, and DPG-POL-Phl p to elicit FcεRI- and FcεRII-mediated IgE responses was measured by basophil activation test and IgE-facilitated allergen binding assay. RESULTS: Analysis revealed that DPG-POL-Phl p downregulated genes associated with TH2 signaling, induced functional regulatory T cells exhibiting immunosuppressive roles through CD52 and Siglec-10, modulated genes encoding immunoproteasome that dysregulate the processing and presentation of antigens to T cells and promoted a shift from IgE toward an IgA1 and IgG responses. In grass pollen-allergic subjects, DPG-POL-Phl p exhibited reduced capacity to elicit proliferation of TH2A, IL-4+ Tfh and IL-21+ Tfh cells while being the most prominent at inducing IL-10+CD19+CD5hi and IL-10+CD19+CD5hiCD38intCD24int regulatory B-cell subsets compared to Phl p (all P < .05). Furthermore, DPG-POL-Phl p demonstrated a hypoallergenic profile through basophil activation and histamine release compared to Phl p (31.54-fold, P < .001). CONCLUSIONS: Single-cell RNA sequencing provides an in-depth resolution of the mechanisms underlying the tolerogenic profile of DPG-POL-Phl p.
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Alérgenos , Hipersensibilidad , Humanos , Poaceae , Interleucina-10 , Leucocitos Mononucleares , Inmunoglobulina E , Polen , Phleum , Alergoides , Extractos Vegetales , Análisis de Secuencia de ARN , Proteínas de PlantasRESUMEN
Carbohydrates in forages constitute an important part of the feed ration for all horses. The aim of the present study was to investigate the effect of harvest time on carbohydrate composition and digestion of various grass species. The experiment was divided into three parts 1) characterization of the chemical composition of experimental feeds (6 grass species: meadow fescue [MF], cocksfoot [CF], perennial ryegrass [PR], smooth bromegrass [SB], tall fescue [TF], and timothy [TI], and 3 harvest times: early, medium, and late first cut), 2) measurements of the in vitro digestion of selected experimental feeds (the 6 grass species, and 2 harvest times [early and late]) measured by in vitro gas production, and 3) in vivo digestion of selected experimental feeds (2 grass species: CF and PR, 2 harvest times [early and late]) measured by the mobile bag technique using caecum cannulated horses. An experimental field was established with plots containing each of the grass species in three replicate blocks. Grass samples were cut between 1200 and 1400 h at 4th of June (early first cut), 17th of June (medium first cut), and 1st of July (late first cut) and analyzed for crude protein (CP), neutral detergent fiber with heat stable amylase and free of residual ash (aNDFom) and water-soluble carbohydrates (WSC). The in vitro fermentation was investigated using the ANKOM RF gas production technique, where feeds were incubated for 48 h using horse caecal fluid as an inoculum. Gas production was modeled, and maximum gas production (MGP) was used to evaluate the potential digestibility of the feeds. Based on the chemical analyses and the in vitro experiment, early and late harvested CF and PR were selected for the in vivo experiment, which was conducted as a randomized 4â ×â 4 Latin square design including four periods, four horses and four feeds. In general, the CP content decreased whereas the aNDFom content increased as the grasses matured. The content of WSC increased in SB and TI, but decreased in CF, and fructans increased in SB, TI, PR, and TF as they matured. The in vitro MGP showed a clearer difference between harvest times than between grass species. Harvest time had larger effect on digestibility than grass species, and a high precaecal disappearance of the WSC fraction was measured by the mobile bag technique. Cocksfoot was identified as a grass species with potentially low digestibility and low WSC content and could potentially be used more for horses.
Feedstuffs contain different carbohydrate fractions that are digested in different parts of the gastrointestinal tract of horses. Grass for grazing or harvesting contains variable amounts of structural carbohydrates such as cellulose and hemi-cellulose (named fibres) and nonstructural carbohydrates which in temperate grass species include sugars and fructans (named water soluble carbohydrates (WSC)). This study quantified carbohydrate composition and digestion of six grass species (perennial ryegrass, timothy, smooth bromegrass, tall fescue, cocksfoot, and meadow fescue) harvested at three different times (early, medium, and late) and preserved as hay. In general, fiber content increased as the grasses matured, whereas WSC content varied to a large extent. In vitro fermentation using horse caecal fluid was used to quantify digestion of early and late cut grass samples of all species. Harvest time (early vs. late) had a larger effect on in vitro fermentation compared to the effect of grass species. Early and late harvested perennial ryegrass and cocksfoot were further selected for detailed studies of precaecal digestion in vivo as these species had highest and lowest WSC content. In general, cocksfoot was identified as grass species with low digestibility and low WSC concentration compared to the other species investigated.
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Festuca , Lolium , Caballos , Animales , Digestión , Carbohidratos , Poaceae/química , Phleum , Dactylis , Proteínas/metabolismo , Alimentación Animal/análisis , Rumen/metabolismoRESUMEN
Summary: Background. The effectiveness of pre-seasonal allergoid immunotherapy in polysensitized patients are not well-known. The aim of the present study was to compare the clinical efficacy and immunological changes of pre-seasonal allergoid immunotherapy in mono and polysensitized patients with grass pollen allergy. Methods. Fourty six patients with seasonal allergic rhinitis undergoing pre-seasonal grass pollen immunotherapy and 28 cases followed by conventional drug treatment were included. These groups were divided into monosensitized and polysensitized ones. All patients were followed between March-September with symptom-medication scores, and visual analogue scale (VAS). The quality of life was assessed using the Mini-RQLQ questionnaire. Phleum pratense (Phl p) specific IgE and IgG4 (UNI-CAP 100, Phadia) measurements were performed before and after 7 weeks of immunotherapy. Results. In the immunotherapy group, 15th weekly symptom-medication scores and VAS scores between May and August were found to be significantly lower than those in the control group (p < 0.05). Phl p specific IgE and IgG4 levels were significantly higher after immunotherapy compared to those before immunotherapy (p = 0.001). Furthermore, Phl p specific IgG4 levels after immunotherapy were also significantly higher than in the control group (p = 0.001). Improvements in activities-practical problems and non-nose/eye symptoms quality of life scores were significantly different between two groups (p < 0.05). There was no difference in terms of clinical and immunological parameters in mono- and polysensitized patients (p > 0.05). Conclusions. This study indicates that clinical improvement with pre-seasonal grass pollen immunotherapy is accompanied by important increase in specific IgG4 blocking antibodies. Furthermore, a single-allergen immunotherapy can lead to similar clinical efficacy and immunological changes in polysensitized as well as monosensitized patients with grass pollen allergy.
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Rinitis Alérgica Estacional , Rinitis Alérgica , Humanos , Rinitis Alérgica Estacional/diagnóstico , Alergoides , Calidad de Vida , Estaciones del Año , Rinitis Alérgica/terapia , Desensibilización Inmunológica/métodos , Resultado del Tratamiento , Inmunoglobulina G , Phleum , Inmunoglobulina E , AlérgenosRESUMEN
Summary: Background.In the diagnostic work up of allergy, determining allergen component-specific immunoglobulin E (IgE) is important for diagnosis, prognosis and choice of treatment. The purpose of this study was to evaluate the performance of the immunoblotting assay (Euroline) in detection of IgE antibodies against timothy grass and birch pollen allergen components compared to fluorescent enzyme assay (ImmunoCAP, Phadia 250). Methods. A total of 128 serum samples from patients allergic to timothy grass and birch pollen were analysed. The levels of IgE antibodies to timothy grass and birch pollen were measured using Euroline DPA-Dx pollen 1 and ImmunoCAP assay. The two methods were then compared on binary (positive vs negative), semi-quantitative (IgE classes) and quantitative (concentration) levels. The two methods were also compared to results from skin prick testing. Results. The Euroline method showed a positive percentage agreement of 93% and negative percentage agreement of 94% with an overall accuracy of 94% when compared to ImmunoCAP. Kappa analysis showed moderate strength of agreement between the methods in determining IgE classes for 7/11 components tested. All components showed a positive correlation when analysed using Spearman's rank correlation. Conclusions. Overall, we found that there is good correlation between the Euroline and ImmunoCAP methods in measuring IgE sensitization.
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Alérgenos , Hipersensibilidad , Humanos , Betula , Poaceae , Hipersensibilidad/diagnóstico , Immunoblotting , Phleum , Inmunoglobulina ERESUMEN
Progress towards standardisation of allergen products has been made in recent years. Nevertheless, no standardised test method to quantify the allergen content of grass pollen allergen products is available at present. One aim of the BSP090 project was to validate a quantitative assay for a major Timothy grass (Phleum pratense) pollen allergen, Phl p 5. Qualification of a candidate ELISA system was performed with regard to range, robustness and cross-reactivity in preliminary studies. The assay specifically detected Phl p 5 with a quantification range from 3.9 ng/mL to 62.5 ng/mL. Suitability to quantify recombinant and natural Phl p 5 was further assessed in a collaborative study including 14 laboratories in Europe and the USA. Precision and accuracy of the assay was satisfactory with 93% of calculated Phl p 5 concentrations and 100% of total recoveries being within the ± 30% acceptance range. Similar results were obtained for spike recoveries, with exclusion of the lowest concentration spike, showing spike recoveries exceeding the acceptance range for six laboratories. Inter-assay (repeatability) and inter-laboratory (reproducibility) variability were satisfactory, in the format used in the present study. Robustness towards different statistical methods for data analysis was demonstrated. In conclusion, the assay can easily be established in routine testing and results of the preliminary testing and collaborative study support the proposal of the assessed Phl p 5-specific ELISA as a European Pharmacopoeia general method.
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Phleum , Polen , Reproducibilidad de los Resultados , Polen/química , Alérgenos/análisis , Ensayo de Inmunoadsorción Enzimática , Proteínas de Plantas/análisisRESUMEN
Timothy is a forage mainly grown in Min County, Gansu Province, China. In 2021, a leaf spot disease outbreak on timothy grass occurred in Min County, adversely affecting its growth and productivity. Therefore, this study investigated the leaf spot disease incidence in Min County, morphologically and molecularly characterized the disease-causing pathogen, and assessed its effects on the growth, photosynthesis, and biomass of timothy seedlings re-inoculated with the isolated pathogen. In the field, the disease incidence on plants and leaves was 100 and 85%, respectively. Morphologically, young lesions were ellipsoidal-fusiform with dark purple margins and an off-white center, while the mature lesions were eye-shaped spots with a light brown center and dark purple edges. Molecular characterization identified the pathogen as Cladosporium phlei causing Cladosporium eyespot disease. The net photosynthetic rate, transpiration rate, fresh shoot weight, and dry shoot weight of timothy seedlings 14 days after inoculation with the pathogen were decreased by 29.77, 56, 45.45, and 46.42%, respectively, implying that Cladosporium eyespot disease is an important timothy grass disease in Min County. Therefore, developing an integrated control strategy is urgent to lessen the economic loss.
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Cladosporium , Phleum , Biomasa , China/epidemiología , Cladosporium/genética , FotosíntesisRESUMEN
Background: Pollen hypersensitivity might be a determining factor for other nonseasonal allergens because it may indicate deviation of the immune system toward T-helper type 2 activity and immunoglobulin E sensitivity. Objective: To investigate whether timothy grass pollen allergy may be a predictive factor for cat sensitization and whether there is an association between sensitivity to both allergens. Method: A retrospective review was made of patients with symptoms of rhinitis. The skin-prick test results and cat ownership status of the patients were analyzed. On the basis of the skin-prick test results with Phleum pratense (timothy grass) and other pollens, the patients were analyzed in two groups: "timothy allergic" and "non-timothy allergic." Results: A total of 383 patients with the diagnosis of rhinitis were included in the study, which comprised 213 (55.6%) in the timothy allergic group and 170 (44.4%) in the non-timothy allergic group. The frequency of cat sensitization was significantly higher in the patients in the timothy allergic group compared with those without timothy grass allergy (33.8% versus 12.3%; p < 0.001). No significant difference was determined between the two groups in terms of cat ownership (p = 0.63). In the logistic regression analysis, cat ownership (adjusted odds ratio [OR] 23.07 [95% confidence interval {CI}, 7.72-68.91]) and timothy allergy (adjusted OR 7.72 [95% CI, 3.16-18.86]) were associated with an increased risk of cat sensitization. Conclusion: Timothy grass allergy may play a role in the development of cat sensitization; however, further research is needed to clarify these associations and the underlying mechanisms.
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Hipersensibilidad , Rinitis , Alérgenos , Humanos , Hipersensibilidad/diagnóstico , Hipersensibilidad/epidemiología , Propiedad , PhleumRESUMEN
BACKGROUND: Mugwort, timothy, and birch are commonly spread pollen allergens across China. Although several studies have described the rates of sensitization to mugwort, timothy, and birch in China, most of them just on specific whole-allergen extracts but little was known about the co-sensitization characteristics of its allergen components. This study aimed to explore the patterns of sensitization to mugwort, timothy, birch, and their major allergen components. METHOD: Serum specific IgE (sIgE) levels of allergen components of mugwort, timothy, birch, and cross-reactive carbohydrate determinants (CCD) were detected in 160 patients whose serum showed positive results to at least one of mugwort, timothy, and birch allergens via EUROBlotMaster system. Skin prick testing was utilized to assess the allergic reaction of grass, weed, and tree allergens. Latent class analysis was used to identify underlying patterns of sensitization to a series of allergen components and their corresponding extracts. RESULTS: 88.8% of patients with allergic rhinitis and/or asthma were positive for mugwort-sIgE, 30% for timothy-sIgE, and 32.5% for birch-sIgE. By using the LCA model, three sensitization patterns as "Mugwort, Art v 4, Bet v 2 and Phl p 12 co-sensitized", "Timothy, mugwort, and CCD co-sensitized", "Mugwort and Art v 1 co-sensitized" were revealed based on optimal statistical fit in this study. Compared with other clusters, participants in "Mugwort, Art v 4, Bet v 2 and Phl p 12 co-sensitized" pattern were associated with higher sensitization rates of common grass and tree pollens allergen. The spearman's coefficient between CCD and timothy was larger than the corresponding values of CCD with mugwort or birch. CONCLUSION: CCD and profilin, as minor allergens in pollens, were associated with other pollen sIgE false positives presumably due to cross-reactivity. Patients sensitized with profilin had a significantly higher risk of sensitization to other pollens.
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Artemisia , Betula , Alérgenos , Reacciones Cruzadas , Humanos , Análisis de Clases Latentes , Phleum , Extractos Vegetales , Poaceae , ProfilinasRESUMEN
INTRODUCTION: There is a need for a fast, efficient and safe way to induce tolerance in patients with severe allergic rhinitis. Intralymphatic immune therapy has been shown to be effective. METHODS: Patients with severe birch and timothy allergy were randomized and received three doses of 0.1 ml of birch and 5-grass allergen extracts (10,000 SQ units/ml, ALK-Abelló), or birch and placebo or 5-grass and placebo by ultrasound-guided injections into inguinal lymph nodes at monthly intervals. Rhinoconjunctivitis total symptom score, medication score and rhinoconjunctivitis quality of life questionnaire were evaluated before treatment and after each birch and grass pollen season during three subsequent years. Circulating proportions of T helper subsets and allergen-induced cytokine and chemokine production were analysed by flow cytometry and Luminex. RESULTS: The three groups reported fewer symptoms, lower use of medication and improved quality of life during the birch and grass pollen seasons each year after treatment at an almost similar rate independently of treatment with one or two allergens. Mild local pain was the most common adverse event. IgE levels to birch decreased, whereas birch-induced IL-10 secretion increased in all three groups. IgG4 levels to birch and timothy and skin prick test reactivity remained mainly unchanged. Conjunctival challenge tests with timothy extract showed a higher threshold for allergen. In all three groups, regulatory T cell frequencies were increased 3 years after treatment. CONCLUSIONS: Intralymphatic immunotherapy with one or two allergens in patients with grass and birch pollen allergy was safe, effective and may be associated with bystander immune modulatory responses. CLINICAL TRIAL REGISTRATION: EudraCT (2013-004726-28).
Asunto(s)
Alérgenos , Rinitis Alérgica , Betula , Método Doble Ciego , Humanos , Factores Inmunológicos , Inmunoterapia , Phleum , Poaceae/efectos adversos , Polen , Calidad de Vida , Rinitis Alérgica/terapia , Resultado del TratamientoRESUMEN
Several species of eriophyid mites are important economic pests of timothy grass in the Mid-Atlantic United States. Feeding causes stunting, curling, and brown discoloration of leaves, and yield losses ranging up to 50%. Carbaryl is the only approved chemical control for these mites. We investigated the population dynamics of field infestations, host plant resistance, and several cultural control measures to develop a more sustainable management strategy. Seasonal phenology and overall abundance differed among timothy fields and between years, with mean peak densities ranging up to 731 eggs and 1,163 mites per 2.5 cm of leaf blade. Population differences were related to the age of the field, the prevailing temperatures, and snow cover during the fall and winter months. All varieties of timothy tested were susceptible, whereas several other forage grasses were significantly resistant to eriophyid mites as possible alternatives for replacing timothy. Fall harvesting reduced the buildup of mites during the winter but populations eventually rebounded and still reached economic densities by April. Burn-down herbicide, prescribed burning, and urea-based fertilizer treatments prior to green-up in the early spring had variable effects and may help to prevent economic losses; however, several concerns about the benefit/costs and practicality of these practices are discussed.