Evidence is compelling for a positive correlation between climate change, urbanisation and prevalence of allergic sensitisation and diseases. The reason for this association is not clear to date. ...Some data point to a pro-allergenic effect of anthropogenic factors on susceptible individuals.
To evaluate the impact of urbanisation and climate change on pollen allergenicity.
Catkins were sampled from birch trees from different sites across the greater area of Munich, pollen were isolated and an urbanisation index, NO2 and ozone exposure were determined. To estimate pollen allergenicity, allergen content and pollen-associated lipid mediators were measured in aqueous pollen extracts. Immune stimulatory and modulatory capacity of pollen was assessed by neutrophil migration assays and the potential of pollen to inhibit dendritic cell interleukin-12 response. In vivo allergenicity was assessed by skin prick tests.
The study revealed ozone as a prominent environmental factor influencing the allergenicity of birch pollen. Enhanced allergenicity, as assessed in skin prick tests, was mirrored by enhanced allergen content. Beyond that, ozone induced changes in lipid composition and chemotactic and immune modulatory potential of the pollen. Higher ozone-exposed pollen was characterised by less immune modulatory but higher immune stimulatory potential.
It is likely that future climate change along with increasing urbanisation will lead to rising ozone concentrations in the next decades. Our study indicates that ozone is a crucial factor leading to clinically relevant enhanced allergenicity of birch pollen. Thus, with increasing temperatures and increasing ozone levels, also symptoms of pollen allergic patients may increase further.
Automatic and Online Pollen Monitoring Oteros, Jose; Pusch, Gudrun; Weichenmeier, Ingrid ...
International archives of allergy and immunology,
01/2015, Letnik:
167, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Pollen are monitored in Europe by a network of about 400 pollen traps, all operated manually. To date, automated pollen monitoring has only been feasible in areas with limited variability in pollen ...species. There is a need for rapid reporting of airborne pollen as well as for alleviating the workload of manual operation. We report our experience with a fully automated, image recognition-based pollen monitoring system, BAA500.
The BAA500 sampled ambient air intermittently with a 3-stage virtual impactor at 60 m3/h in Munich, Germany. Pollen is deposited on a sticky surface that was regularly moved to a microscope equipped with a CCD camera. Images of the pollen were constructed and compared with a library of known samples. A Hirst-type pollen trap was operated simultaneously.
Over 480,000 particles sampled with the BAA500 were both manually and automatically identified, of which about 46,000 were pollen. Of the automatically reported pollen, 93.3% were correctly recognized. However, compared with manual identification, 27.8% of the captured pollen were missing in the automatic report, with most reported as unknown pollen. Salix pollen grains were not identified satisfactorily. The daily pollen concentrations reported by a Hirst-type pollen trap and the BAA500 were highly correlated (r = 0.98).
The BAA500 is a functional automated pollen counter. Its software can be upgraded, and so we expected its performance to improve upon training. Automated pollen counting has great potential for workload reduction and rapid online pollen reporting.
There is high demand for online, real-time and high-quality pollen data. To the moment pollen monitoring has been done manually by highly specialized experts.
Here we evaluate the electronic Pollen ...Information Network (ePIN) comprising 8 automatic BAA500 pollen monitors in Bavaria, Germany. Automatic BAA500 and manual Hirst-type pollen traps were run simultaneously at the same locations for one pollen season. Classifications by BAA500 were checked by experts in pollen identification, which is traditionally considered to be the “gold standard” for pollen monitoring.
BAA500 had a multiclass accuracy of over 90%. Correct identification of any individual pollen taxa was always >85%, except for Populus (73%) and Alnus (64%). The BAA500 was more precise than the manual method, with less discrepancies between determinations by pairs of automatic pollen monitors than between pairs of humans. The BAA500 was online for 97% of the time. There was a significant correlation of 0.84 between airborne pollen concentrations from the BAA500 and Hirst-type pollen traps. Due to the lack of calibration samples it is unknown which instrument gives the true concentration.
The automatic BAA500 network delivered pollen data rapidly (3 h delay with real-time), reliably and online. We consider the ability to retrospectively check the accuracy of the reported classification essential for any automatic system.
•A fully automatic pollen Network was built in Bavaria, based on the system BAA500.•BAA500 had a multiclass accuracy of over 90%.•There was a significant correlation of 0.84 between BAA500 and Hirst data.
Primary biological aerosol particles (PBAP) such as pollen and fungal spores can induce allergenic responses and affect health in general. Conditions such as allergic rhinitis (hay fever) and asthma ...have been related to pollen concentrations. Likewise some pollen have been shown to induce ice nucleation and cloud condensation at higher temperatures than those associated with some chemical species, thereby affecting planet Earth's albedo and overall radiative balance. Hence, the near real-time (on-line) monitoring of airborne pollen and other PBAP using a variety of spectroscopic and light scattering techniques represents an area of growing development and consequence.
In this study, two separate field campaigns (one at a rural site in Ireland and the other at an urbanized location in Germany) were performed to detect and quantify pollen releases using a novel on-line fluorescence spectrometer (WIBS-4). The results were compared with results obtained using more traditional Hirst-type impactors. Size, "shape," and fluorescence characteristics of ambient particles were used to determine the concentrations and identity of the PBAP likely to be pollen grains.
The concentration results obtained for both methodologies at both the Irish and German sites correlated very well, with R
2
values >0.9 determined for both campaigns. Furthermore, the sizing data available from the WIBS-4 approach employed in Ireland indicated that pollen grains can be identified in appropriate conditions. WIBS-4 measurements of Yew pollen both in the laboratory and at the rural site indicated almost identical size ranges of 25 to 27 μm. Yew pollen is generally reported to be in this range, but the measurements reported here are the first of their type providing data on the size of in-flight Yew pollen.
Copyright 2014 American Association for Aerosol Research
Exposure to allergens is pivotal in determining sensitization and allergic symptoms in individuals. Pollen grain counts in ambient air have traditionally been assessed to estimate airborne allergen ...exposure. However, the exact allergen content of ambient air is unknown. We therefore monitored atmospheric concentrations of birch pollen grains and the matched major birch pollen allergen Bet v 1 simultaneously across Europe within the EU-funded project HIALINE (Health Impacts of Airborne Allergen Information Network).
Pollen count was assessed with Hirst type pollen traps at 10 l min−1 at sites in France, United Kingdom, Germany, Italy and Finland. Allergen concentrations in ambient air were sampled at 800 l min−1 with a Chemvol® high-volume cascade impactor equipped with stages PM > 10 μm, 10 μm > PM > 2.5 μm, and in Germany also 2.5 μm > PM > 0.12 μm. The major birch pollen allergen Bet v 1 was determined with an allergen specific ELISA. Bet v 1 isoform patterns were analyzed by 2D-SDS-PAGE blots and mass spectrometric identification. Basophil activation was tested in an FcɛR1-humanized rat basophil cell line passively sensitized with serum of a birch pollen symptomatic patient.
Compared to 10 previous years, 2009 was a representative birch pollen season for all stations. About 90% of the allergen was found in the PM > 10 μm fraction at all stations. Bet v 1 isoforms pattern did not vary substantially neither during ripening of pollen nor between different geographical locations. The average European allergen release from birch pollen was 3.2 pg Bet v 1/pollen and did not vary much between the European countries. However, in all countries a >10-fold difference in daily allergen release per pollen was measured which could be explained by long-range transport of pollen with a deviating allergen release. Basophil activation by ambient air extracts correlated better with airborne allergen than with pollen concentration.
Although Bet v 1 is a mixture of different isoforms, its fingerprint is constant across Europe. Bet v 1 was also exclusively linked to pollen. Pollen from different days varied >10-fold in allergen release. Thus exposure to allergen is inaccurately monitored by only monitoring birch pollen grains. Indeed, a humanized basophil activation test correlated much better with allergen concentrations in ambient air than with pollen count. Monitoring the allergens themselves together with pollen in ambient air might be an improvement in allergen exposure assessment.
► We monitored the allergen release from birch pollen at several locations in Europe simultaneously. ► The allergen content of pollen measured by ELISA varied >10-fold between days at all stations. ► The reaction of human immune cells (basophils) correlated better with allergen release from pollen than with pollen count. ► Different potency of pollen could be explained by different geographical origin of the pollen.
The level of symptoms in pollen allergy sufferers and users of the Patient's Hayfever Diary (PHD), does not directly reflect the total amount of pollen in the air. It is necessary to explain the ...symptom load and thus the development of allergic symptoms and to determine which environmental factors, besides the pollen load, influence variables. It seems reasonable to suspect allergen content because the amount of allergen varies throughout seasons and regions and is not always correlated with the total pollen amount.
Data on the allergen content of ambient air (Bet v 1 and Phl p 5) from 2009 until 2011 was used to compare the respective pollen and symptom loads for study regions in Austria, Germany, France and Finland.
Our findings suggest that allergen amount (Bet v 1/Phl p 5) has a strong but regionally dependent impact on the symptom load of pollen allergy sufferers. Peak symptom loads can be traced with peak allergen loads. The influence of other important aeroallergens should also be assessed during the pollen season.
Allergen concentrations have an impact on pollen allergy sufferers although not as clear as assumed previously. The pattern of pollen load and major allergen content distribution does not directly explain the symptom load pattern, although significant positive correlations were found. Thus, monitoring of symptoms via voluntary crowdsourcing should be considered for future pollen and symptom forecasts in order to support pollen allergy sufferers.
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•Allergen content is currently a main suspect for having a direct impact on symptoms.•Measurements of main allergens (Bet v 1/Phl p 5) explain peaks in the symptom load.•A direct pattern between the symptom level and the allergen content was not found.•A focus on the development and onset of allergy symptoms is needed in monitoring.
Airborne pollen is a recognized biological indicator and its monitoring has multiple uses such as providing a tool for allergy diagnosis and prevention. There is a knowledge gap related to the ...distribution of pollen traps needed to achieve representative biomonitoring in a region. The aim of this manuscript is to suggest a method for setting up a pollen network (monitoring method, monitoring conditions, number and location of samplers etc.). As a case study, we describe the distribution of pollen across Bavaria and the design of the Bavarian pollen monitoring network (ePIN), the first operational automatic pollen network worldwide.
We established and ran a dense pollen monitoring network of 27 manual Hirst-type pollen traps across Bavaria, Germany, during 2015. Hierarchical cluster analysis of the data was then performed to select the locations for the sites of the final pollen monitoring network. According to our method, Bavaria can be clustered into three large pollen regions with eight zones. Within each zone, pollen diversity and distribution among different locations does not vary significantly. Based on the pollen zones, we opted to place one automatic monitoring station per zone resulting in the ePIN network, serving 13 million inhabitants. The described method defines stations representative for a homogeneous aeropalynologically region, which reduces redundancy within the network and subsequent costs (in the study case from 27 to 8 locations). Following this method, resources in pollen monitoring networks can be optimized and allergic citizens can then be informed in a timely and effective way, even in larger geographical areas.
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•The first automatic pollen monitoring network in the world was built in Bavaria, based on the pollen robot BAA500.•Collapsing a dense network by clustering analysis determined the number and position of monitoring stations.•Bavaria (Germany) can be clustered in 3 pollen zones and 8 sub-zones, based on airborne pollen concentrations.•In the studied network, the most abundant pollen types in Bavaria are: Pinus, Betula, Urticaceae and Poaceae.•In the studied network, the main pollination period in Bavaria ranges from February (Alnus) to October (Ambrosia).
Studies have linked daily pollen counts to respiratory allergic health outcomes, but few have considered allergen levels.
We sought to assess associations of grass pollen counts and grass allergen ...levels (Phl p 5) with respiratory allergic health symptoms in a panel of 93 adults with moderate-severe allergic rhinitis and daily asthma hospital admissions in London, United Kingdom.
Daily symptom and medication scores were collected from adult participants in an allergy clinical trial. Daily counts of asthma hospital admissions in the London general population were obtained from Hospital Episode Statistics data. Daily grass pollen counts were measured using a volumetric air sampler, and novel Phl p 5 levels were measured using a ChemVol High Volume Cascade Impactor and ELISA analyses (May through August). Associations between the 2 pollen variables and daily health scores (dichotomized based on within-person 75th percentiles) were assessed using generalized estimating equation logistic models and with asthma hospital admissions using Poisson regression models.
Daily pollen counts and Phl p 5 levels were each positively associated with reporting a high combined symptom and medication health score in separate models. However, in mutually adjusted models including terms for both pollen counts and Phl p 5 levels, associations remained for Phl p 5 levels (odds ratio 95% CI: 1.18 1.12, 1.24), but were heavily attenuated for pollen counts (odds ratio 95% CI: 1.00 0.93, 1.07). Similar trends were not observed for asthma hospital admissions in London.
Grass allergen (Phl p 5) levels are more consistently associated with allergic respiratory symptoms than grass pollen counts.
The daily pollen forecast provides crucial information for allergic patients to avoid exposure to specific pollen. Pollen counts are typically measured with air samplers and analyzed with microscopy ...by trained experts. In contrast, this study evaluated the effectiveness of identifying the component pollens using the metabolites extracted from an air-sampled pollen mixture. Ambient air-sampled pollen from Munich in 2016 and 2017 was visually identified from reference pollens and extracts were prepared. The extracts were lyophilized, rehydrated in optimal NMR buffers, and filtered to remove large proteins. NMR spectra were analyzed for pollen associated metabolites. Regression and decision-tree based algorithms using the concentration of metabolites calculated from the NMR spectra outperformed algorithms using the NMR spectra themselves as input data for pollen identification. Categorical prediction algorithms trained for low, medium, high, and very high pollen count groups had accuracies of 74% for the tree, 82% for the grass, and 93% for the weed pollen count. Deep learning models using convolutional neural networks performed better than regression models using NMR spectral input, and were the overall best method in terms of relative error and classification accuracy (86% for tree, 89% for grass, and 93% for weed pollen count). This study demonstrates that NMR spectra of air-sampled pollen extracts can be used in an automated fashion to provide taxa and type-specific measures of the daily pollen count.
•This study identified the component pollens from metabolites extracted from air-sampled pollen.•Deep learning methods trained on NMR spectra directly were the best performing algorithms.•Automated analyses of air-sampled pollen extracts using NMR can provide the daily pollen count.
The mechanisms how environmental compounds influence the human immune system are unknown. The environmentally sensitive transcription factor aryl hydrocarbon receptor (AHR) has immune-modulating ...functions and responds to small molecules. Cytochrome P4501 enzymes (CYP1) act downstream of the AHR and metabolize small molecules. However, it is currently unknown whether CYP1 activity is relevant for immune modulation. We studied the interdependence of CYP1 and AHR in human primary immune cells using pharmacological methods. CYP1 inhibition increased the expression levels of the stem cell factor receptor (c-Kit) and interleukin (IL)-22 but decreased IL-17. Single cell analyses showed that CYP1 inhibition especially promoted CD4
helper T (Th) cells that co-express c-Kit and IL-22 simultaneously. The addition of an AHR antagonist reversed all these effects. In addition to T cells, we screened other human immune cells for CYP and found cell-specific fingerprints, suggesting that similar mechanisms are present in multiple immune cells. We describe a feedback loop yet unknown in human immune cells where CYP1 inhibition resulted in an altered AHR-dependent immune response. This mechanism relates CYP1-dependent metabolism of environmental small molecules to human immunity.