Major Aeroallergens Research Articles

Seasonal Patterns and Allergenicity of Casuarina Pollen in Sydney, Australia: Insights from 10 Years of Monitoring and Skin Testing

Casuarina (Australian pine, She-oak) is native to Australia and South East Asia and is known for its abundant wind-borne pollen. Despite not being considered a major aeroallergen, some patients report respiratory symptoms upon exposure, with positive skin prick tests (SPT) to Casuarina pollen extract. This study investigates Casuarina pollen dispersal patterns in Sydney, Australia, over a 10-year period, from 2008 to 2018, revealing a bimodal distribution of pollen from September to October (southern hemisphere spring) and February to March (mid-late summer). Analysis of historical SPT data shows 20% of individuals with respiratory allergies reacting positively to Casuarina pollen extract, with almost 90% of these also reacting to grass pollen, suggesting potential cross-reactivity. Notably, there are no exclusive reactions to Casuarina pollen. Understanding the prolonged pollen season underscores the importance of year-round monitoring for accurate characterization. Currently lacking are commercially available skin test extracts or specific IgE assays for Casuarina sensitization, necessitating challenge studies to confirm clinical symptoms directly attributable to Casuarina pollen. By elucidating the seasonal dynamics and meteorological drivers of Casuarina pollen dispersion, alongside the potential allergenicity suggested by skin prick tests, this study paves the way for improved management of Casuarina-related allergies and highlights the critical need for further research on native Australian plant allergens.

Screening of B-cell epitopes of Der-p1 and Der-p2 major aeroallergens by computational approach for designing immunotherapeutics

Introduction and Aim: Allergic diseases are IgE-mediated hypersensitivity reactions affecting approximately 30% of the general population globally. Dermatophagoides pteronyssinus (Der-p) is the most prevalent house dust mite (HDM) species consisting of 23 mite allergen groups. Among these, group 1 and 2 are major allergenic proteins, which causes allergic asthma in 80% of sensitized individuals, with elevated IgE titres in the serum. This study involves in silico analysis of potential B-cell epitopes of group 1 and group 2 of Der-p, which can be utilized in designing immunotherapeutic vaccines. Materials and Methods: Allergen sequences obtained from the database- International Union of Immunological Societies (IUIS), for predicting of B-cell epitopes. The physiochemical properties and secondary structures of the obtained sequence were evaluated. The sequences were further subjected to determining antigenicity, surface accessibility, and prediction of linear and discontinuous B-cell epitope by utilizing IEDB tools. Results: The linear and discontinuous B-cell epitopes of Der-p1 and Der-p2 aeroallergen were predicted. Further, Der-p1 and Der-p2 showed 6 linear epitopes each respectively. Conformational epitopes predicted were 123 of Der-p1 and 72 of Der-p2 respectively, by the ElliPro tool. Based on the structure, antigenicity, and surface accessibility, only 10% of Der-p1 and Der-p2 which binds to B-cell epitopes are linear and the majority are discontinuous. Conclusion: The linear and conformational epitopes of Der-p1 and Der-p2 are predicted using in silico tools. These identified epitopes might be useful for developing epitope-based immunotherapeutics for HDM allergy.

Modeling past and future spatiotemporal distributions of airborne allergenic pollen across the contiguous United States.

Exposures to airborne allergenic pollen have been increasing under the influence of changing climate. A modeling system incorporating pollen emissions and atmospheric transport and fate processes has been developed and applied to simulate spatiotemporal distributions of two major aeroallergens, oak and ragweed pollens, across the contiguous United States (CONUS) for both historical (year 2004) and future (year 2047) conditions. The transport and fate of pollen presented here is simulated using our adapted version of the Community Multiscale Air Quality (CMAQ) model. Model performance was evaluated using observed pollen counts at monitor stations across the CONUS for 2004. Our analysis shows that there is encouraging consistency between observed seasonal mean concentrations and corresponding simulated seasonal mean concentrations (oak: Pearson = 0.35, ragweed: Pearson = 0.40), and that the model was able to capture the statistical patterns of observed pollen concentration distributions in 2004 for most of the pollen monitoring stations. Simulation of pollen levels for a future year (2047) considered conditions corresponding to the RCP8.5 scenario. Modeling results show substantial regional variability both in the magnitude and directionality of changes in pollen metrics. Ragweed pollen season is estimated to start earlier and last longer for all nine climate regions of the CONUS, with increasing average pollen concentrations in most regions. The timing and magnitude of oak pollen season vary across the nine climate regions, with the largest increases in pollen concentrations expected in the Northeast region.

Do we need aerobiological air monitoring in desert climates? The Qatar experience.

Knowledge about diurnal, seasonal, and annual fluctuations in airborne pollen and fungal spores in any geographical area is essential for effective diagnosis and treatment of allergies. Aerobiological analysis enables the detection of airborne pollen and spores, thus providing information on plant phenology, plant distribution, related diseases, and the risks for some species in terms of allergies. Although pollen and fungal spores have been widely studied as aeroallergens throughout the world, not much is known about the biological aerosols in countries with a desert environment; and these could be present in much higher concentrations than expected. Arid desert regions (including the region surrounding the Arab Gulf), characterized by hot weather, poor soils, and low biological productivity, have typically been neglected when building ambitious biomonitoring networks for the large-scale monitoring of biological particles; however, few studies in Kuwait, Saudi Arabia, and recently Qatar have aimed to delineate the various botanical families that contribute to inhalant allergens in this region.Understanding the aerobiological features of countries with hot and desert climates may better prepare healthcare providers to assist patients with allergic rhinitis. It may be argued that one of the reasons why aerobiologists have only recently turned their attention to the state of Qatar investigating how pollen and fungal spore records could contribute to evaluating the correlation between different pollen conditions and allergy symptoms.The first aerobiological network of Qatar was monitoring (2017–2020) the atmospheric pollen concentrations of Doha and Al Khor to determine the association between the possible risk of respiratory allergies and the distribution of certain species throughout the region. In the Qatari database, more than 25 native taxa have been recorded, up to 50% of which can be considered allergenic. This includes Amaranthaceae and Poaceae pollen among the major aeroallergens causing allergy symptoms in Qatar. Our study has confirmed a statistically significant association between Amaranthaceae and asthma and allergic rhinitis. To summarize, it is worth considering aerobiological monitoring in desert climate regions when assessing the effectiveness of pollen allergy therapy and planning prevention methods for patients.

Characterization and Sensitivity Test of the Allergenic Pollen Proteins from Litchi Chimensis Plant

Pollen of Litchi chinensis (Litchi) is a major aeroallergen of Bangladesh. Pollen of this fruits plant was collected from full bloomed flower growing in different places of Rajshahi in Bangladesh. Pollen protein was extracted and partial purified by means of long-term PBS extraction, salting out, dialysis, gel filtrations and DEAE-Cellulose chromatography and the protein was designated as LFPP (Litchi flowers pollen protein). Gel filtration of the purified pollen protein gives two main peaks. The major peak gives four bands on SDS-PAGE. The enzyme (pectate lyase) proteins after gel filtration again re-purified by Ion exchange chromatography, a single band in the protein profile of LFPP, (M.W. 28kDa) was the major allergenic component of Litchi chinensis (Litchi) flower pollen. The homogeneity and the molecular weight of the protein were estimated by SDS-PAGE, and Gel filtration was 28kDa. The allergenic protein was identified by skin prick tests and showed the pectate lyase (Pel) activity. Skin-prick tests also revealed highest degree of sensitivity to the Nawabgang sample giving positive response in 80% of the patients. Skin reactivity ranged between 1+ and 3+.

Airborne Cupressaceae Pollen and Its Major Allergen, Cup a 1, in Urban Green Areas of Southern Iberian Peninsula

Cupressaceae pollen is responsible for winter respiratory allergies in the Mediterranean area. Pollen grains of this diverse family share the same characteristics under light microscopy. Consequently, the partial contribution of each Cupressaceae species to the airborne pollen spectrum cannot be determined with conventional aerobiological methods. Studies on major aeroallergens offer better information on the allergic sensitization and appearance of symptoms in patients sensitized to airborne pollen and spores. Our aim was to determine if airborne Cupressaceae pollen concentrations correspond to aerodynamics of the major allergen of Cupressus (Cup a 1), as well as the aeroallergen correlation with different-sized particles. The air was sampled in two cities of Southern Spain (Granada and Córdoba) using the Hirst-type volumetric sampler for airborne pollen detection during 2006 to 2008 and the Andersen Cascade Impactor for aeroallergen detection during the main pollination period of Cupressaceae in the same period. The samples were analyzed by the methodology proposed by the Spanish Aerobiology Network (REA), the minimum requirements of the European Aeroallergen Society (EAS) for pollen, and by ELISA immunoassay to detect airborne Cup a 1. The distribution patterns of airborne Cupressaceae pollen and Cup a 1 were observed throughout the sampling period, although with some irregular oscillations. Cupressaceae pollen and Cup a 1 showed positive and significant correlation during the period of maximum concentrations (January to March). However, the results of this study showed that the period of exposure of aeroallergens depends on the Cupressus species and their abundance in cities. According to the allergy potential obtained, species like C. arizonica could release more allergens than other species like C. sempervirens.

Sex- and Age-Dependent Changes in Polysensitization to Common Aeroallergens Over 20 Years.

IntroductionThe prevalence of airway allergies in Europe has increased from 23% to 31% in recent years. Polysensitization is associated with the development and severity of relevant allergies, particularly allergic asthma.ObjectiveWe investigated age- and sex-dependent monosensitization and polysensitization profiles as well as patterns of sensitization using skin prick test (SPT) reactivity to the most common aeroallergens.Patients and MethodsFrom 1998 to 2017, SPTs were retrospectively analyzed in 2886 symptomatic patients, referred to the University Medical Center Göttingen, located in central Germany. The major aeroallergen groups early flowering tree pollen, grass pollen, and house dust mites were evaluated in this study. Wheal diameters ≥2 mm were considered positive during the entire study period.ResultsPolysensitization to the most common aeroallergen groups increased significantly over 20 years. Boys and young men displayed the most remarkable rise in total sensitization rates in our study group over time.DiscussionOur patient-based study demonstrates a continuing increase in polysensitization rates over the last 20 years, with boys and young men being most frequently affected. Our data—without being a population-based study—suggest a scenario with climbing rates of allergic rhinitis and asthma.

High post-season Alnus pollen loads successfully identified as long-range transport of an alpine species

Abstract Alnus pollen is one of the Northern Hemisphere's major aeroallergens. In Central Europe, the genus is represented by three species (Alnus glutinosa, Alnus incana, and Alnus viridis). The most common one, A. glutinosa (L.) Gaertn., is widespread in lowland riparian forests, swamps, and forest edges. However, to date is still unknown if all of them - in terms of pollen exposure - are clinically relevant for sensitized individuals. To investigate the associated pollen exposure, particularly also because of long-range transport of airborne pollen, we used backward air mass trajectories and tested this method for the year 2015, based on daily Alnus pollen concentrations at 26 sites in Bavaria, Germany. A. glutinosa's main pollen season extends from February to March, but a six-day, post-season episode was additionally identified in June. For this episode and all sites, 72-h backward trajectories were calculated at 3-h intervals using high spatial and temporal resolution ERA5 reanalysis data and the HYSPLIT (hybrid single-particle Lagrangian integrated trajectory) model. This backward trajectory method identified air masses from the alpine region in Switzerland and Austria, where relevant areas of A. viridis (Chaix) DC as potential pollen sources exist. These may explain the post-season episode in June, as additionally confirmed by its unique spatial distribution, by a considerably later flowering period, and by repeated long-range transport events as observed in a 23-year pollen time series.

Biogeographical variation in specific IgE recognition of temperate and subtropical grass pollen allergens in allergic rhinitis patients.

ObjectiveGlobally, grass pollens (GP) are major aeroallergen triggers of allergic rhinitis (AR) and asthma. However, patterns of allergic sensitisation to pollen of temperate (Pooideae: Lolium perenne) and subtropical (Chloridoideae: Cynodon dactylon and Panicoideae: Paspalum notatum) subfamilies in diverse climates remain unclear. This study aims to evaluate the level of allergic sensitisation and IgE specificity for major GP allergens representing the three subfamilies in biogeographically distinct regions.MethodsParticipants (GP‐allergic with AR, 330; non‐atopic, 29; other allergies, 54) were recruited in subtropical: Queensland, and temperate: New South Wales, Western and South Australia, regions. Clinical history, skin prick test (SPT), total and specific IgE to GP and purified allergens (ImmunoCAP) were evaluated. Cross‐inhibition of sIgE with Pas n 1, Cyn d 1 and Lol p 1 by GP extracts was investigated.ResultsQueensland participants showed higher sensitisation to P. notatum and C. dactylon than L. perenne GP. sIgE was higher to Pas n 1 and Cyn d 1, and sIgE to Pas n 1 and Cyn d 1 was inhibited more by Panicoideae and Chloridoideae, respectively, than Pooideae GP. Conversely, participants from temperate regions showed highest sensitisation levels to L. perenne GP and Lol p 1, and sIgE to Lol p 1 was inhibited more by Pooideae than other GP.ConclusionLevels and patterns of sensitisation to subtropical and temperate GP in AR patients depended on biogeography. Knowledge of the specificity of sensitisation to local allergens is important for optimal diagnosis and choice of allergen‐specific immunotherapy to maximise benefit.

Allergic Rhinitis to Weed Pollen in Germany: Dominance by Plantain, Rising Prevalence, and Polysensitization Rates over 20 Years

Background: In contrast to the 3 major aeroallergens tree pollen, grass pollen, and house dust mites, allergic rhinitis caused by herbal pollen has received comparatively little attention in recent clinical studies. Since various weeds flower during summer until fall, allergic rhinitis to weeds may be underdiagnosed and/or mistakenly diagnosed as grass pollen allergy. Objective: To investigate (i) the currently most frequent weed allergy between mugwort, ragweed, plantain, chamomile, nettle, and oilseed rape and (ii) time trends in prevalence of sensitization to weed pollen in the middle of Germany over the last 20 years. Methods: This study, the largest of its kind to date, monocentrically evaluated the prick test results of a total of 6,220 patients with suspected RCA over a period of 20 years (1998–2017). Results: In the study cohort, sensitization rates to plantain almost doubled from 26.6% in the decade 1998–2007 to 50.5% in 2008–2017. Identical increases were observed for ragweed, while sensitization rates for mugwort stayed largely unchanged. The most prominent increase in positive skin prick tests to plantain and ragweed pollen was mainly observed in younger patients. Further, we identified a trend toward polysensitization, currently dominated by plantain and ragweed. Sensitization to weed pollen was found to be highly associated with additional sensitizations to grass and/or birch pollen. Conclusion: Plantain is currently the best choice to screen rhinitis patients for weed allergy which identifies 86% of all weed-sensitized individuals, at least in Germany. Over the last 20 years, we demonstrate a significant rise in the total number of weed pollen sensitization as well as increases in polysensitization, predominantly in younger patients.

Impacts of CD40- and CD86-Silenced Antigen-Specific B Cells on the Control of Allergies.

Background We previously reported that CD40-silenced B cells inhibited allergic responses and symptoms. However, more potent therapies are needed. To our knowledge, the effects of CD86-silenced B cells and synergic effects of gene silencing in B cells by 2 small interfering RNAs (siRNAs) on allergic disease control have not been reported. Objective To investigate the effects of CD86-silenced B cells and synergic effects of gene silencing in B cells on allergic responses and symptoms. Methods Mice were treated with CD40- and/or CD86-silenced B cells transfected with siRNAs and pulsed with ovalbumin (OVA). And the effects of these B cells were estimated. Results CD86-silenced OVA-pulsed B cells significantly inhibited OVA-induced allergies. Treatment with CD40-/CD86-silenced OVA-pulsed B cells led to a significantly fewer sneezes and nasal rubbing movements, as well as lower OVA-specific immunoglobulin E (IgE) levels, than that with CD40-silenced or CD86-silenced OVA-pulsed B cells alone. These inhibitory effects were observed prior to sensitization as well as after the establishment of allergic rhinitis. CD40-/CD86-silenced OVA-pulsed B cells did not inhibit keyhole limpet hemocyanin-induced allergies. CD40-/CD86-silenced OVA-pulsed B cells also significantly inhibited allergic symptoms and OVA-specific IgE level in sera compared with CD40-/CD86-silenced OVA-pulsed dendritic cells (DCs). In addition, CD19+CD40− B cells significantly increased in the nasal tissue after intravenous administration of these cells. Furthermore, CD40-/CD86-silenced B cells inhibited allergic symptoms caused by Cry j 1, a major aeroallergen of Japanese cedar pollen, and Cry j 1-specific IgE in sera. Conclusion This study showed, for the first time, that siRNA-induced CD86-silenced B cells significantly inhibited allergic responses and symptoms antigen-specifically, and that siRNA-induced CD40-/CD86-silenced antigen-specific B cells are a more useful antigen-specific therapy than CD40- or CD86-silenced B cells alone for the control of allergies. Furthermore, it was shown that CD40-/CD86-silenced B cells have stronger inhibition of IgE production and allergic symptoms than CD40-/CD86-silenced DCs.

The Dermatophagoides pteronyssinus Molecular Sensitization Profile of Allergic Rhinitis Patients in Central China.

Background House dust mites (HDMs) are the major aeroallergens in patients with rhinitis and/or asthma in China. However, the molecular sensitization of HDM is varied in different regions. Objective To investigate the Dermatophagoides pteronyssinus ( Der p) molecular sensitization profile of allergic rhinitis (AR) patients in Central China. Methods AR patients with positive skin prick tests to Der p were enrolled in our study. Specific immunoglobulin E (sIgE) for Der p, Dermatophagoides farinae ( Der f), Acarus siro ( Aca s), Blomia tropicalis ( Blo t), and Der p components Der p1, Der p2, and Der p10 were measured in all patients. Results A total of 130 patients were included. The overall prevalence of positive serum sIgE was 99.2% for Der p, 98.5% for Der f, 81.5% for Aca s, 83.1% for Blo t, 71.5% for Der p1, 64.6% for Der p2, and 11.5% for Der p10. HDM-AR patients with asthma displayed significantly higher concentrations of sIgE to Der p, Der f, Der p1, and Der p2 than did those without asthma ( P < .001). The prevalence of asthma in HDM-AR patients was higher among the patients sensitized to both Der p1 and Der p2 (62.8%) than those sensitized to only 1 allergen ( Der p1 26.7% or Der p2 16.7%; P < .05) or nonsensitized to Der p1 and Der p2 (19.4%; P < .001). Conclusion Der p has high cross-reactivity with other mite species. Der p1 and Der p2 are the major components to induce Der p sensitization among AR patients in Central China. Sensitization to both Der p1 and Der p2 may be a risk factor for developing asthma in HDM-AR patients.

Is there an advantage to staying indoors for pollen allergy sufferers? Composition and quantitative aspects of the indoor pollen spectrum

The pollen content of the air in an office was assessed together with the dust on the floor and on the desktops as well as the pollen content outside of the building on rooftops and at ground level. The whole pollen spectrum was evaluated (35 different pollen types) with focus on the major aeroallergens. The air samples were measured with Hirst-type pollen traps and the dust samples were evaluated following guidelines in forensic palynology. The same time period was examined on four different sampling days: (1) during the winter as a reference day, (2) during the main pollination period of Betula, (3) during the main pollination period of Poaceae and (4) during the main pollination period of Ambrosia. Pollen concentrations were generally lower in indoor air than in outdoor air (except for the winter day), but showed associations with dust by containing non-seasonal pollen types as well as seasonal pollen. Staying indoors is recommended for pollen allergy sufferers, but does not grant the absence of pollen or the total avoidance of symptoms. Results indicate that persons concerned should keep in mind being confronted with pollen in certain amounts throughout the year indoors in built environment.

Charting novel allergens from date palm pollen (Phoenix sylvestris) using homology driven proteomics

Pollen grains from Phoenix sylvestris (date palm), a commonly cultivated tree in India has been found to cause severe allergic diseases in an increasing percentage of hypersensitive individuals. To unearth its allergenic components, pollen protein were profiled by two-dimensional gel electrophoresis followed by immunoblotting with date palm pollen sensitive patient sera. Allergens were identified by MALDI-TOF/TOF employing a layered proteomic approach combining conventional database dependent search and manual de novo sequencing followed by homology-based search as Phoenix sylvestris is unsequenced. Derivatization of tryptic peptides by acetylation has been demonstrated to differentiate the ‘b’ from the ‘y’ ions facilitating efficient de novo sequencing. Ten allergenic proteins were identified, out of which six showed homology with known allergens while others were reported for the first time. Amongst these, isoflavone reductase, beta-conglycinin, S-adenosyl methionine synthase, 1, 4 glucan synthase and beta-galactosidase were commonly reported as allergens from coconut pollen and presumably responsible for cross-reactivity. One of the allergens had IgE binding epitope recognized by its glycan moiety. The allergenic potency of date palm pollen has been demonstrated using in vitro tests. The identified allergens can be used to develop vaccines for immunotherapy against date palm pollen allergy. The significance of the studyIdentification of allergenic proteins from sources harboring them is essential in developing therapeutic interventions. This is the first comprehensive study on the identification of allergens from Phoenix sylvestris (date palm) pollen, one of the major aeroallergens in India using a proteomic approach. Proteomic methods are being increasingly used to identify allergens. However, since many of these proteins arise from species which are un-sequenced, it becomes difficult to interpret those using conventional proteomics. Date palm being an unsequenced species, the IgE-reactive proteins have been identified using a stratified proteomic workflow incorporating manual de novo sequencing and homology-based proteomics. This study also gives an insight into the presence of glycan nature of the IgE binding epitopes. Five proteins have been found to be common with coconut pollen allergens and presumably responsible for cross-reactivity. These can be used in diagnostics to differentiate patient cohorts allergic to both coconut and date palm pollen from true date palm pollen allergic subjects. This would also determine better specific immunotherapy regimes between the two cohorts. The allergens identified herein have potential towards vaccine development in date palm pollen allergy as well as in enriching the existing catalogue of allergenic proteins.

Mechanistic species distribution modeling reveals a niche shift during invasion.

Niche shifts of nonnative plants can occur when they colonize novel climatic conditions. However, the mechanistic basis for niche shifts during invasion is poorly understood and has rarely been captured within species distribution models. We quantified the consequence of between-population variation in phenology for invasion of common ragweed (Ambrosia artemisiifolia L.) across Europe. Ragweed is of serious concern because of its harmful effects as a crop weed and because of its impact on public health as a major aeroallergen. We developed a forward mechanistic species distribution model based on responses of ragweed development rates to temperature and photoperiod. The model was parameterized and validated from the literature and by reanalyzing data from a reciprocal common garden experiment in which native and invasive populations were grown within and beyond the current invaded range. It could therefore accommodate between-population variation in the physiological requirements for flowering, and predict the potentially invaded ranges of individual populations. Northern-origin populations that were established outside the generally accepted climate envelope of the species had lower thermal requirements for bud development, suggesting local adaptation of phenology had occurred during the invasion. The model predicts that this will extend the potentially invaded range northward and increase the average suitability across Europe by 90% in the current climate and 20% in the future climate. Therefore, trait variation observed at the population scale can trigger a climatic niche shift at the biogeographic scale. For ragweed, earlier flowering phenology in established northern populations could allow the species to spread beyond its current invasive range, substantially increasing its risk to agriculture and public health. Mechanistic species distribution models offer the possibility to represent niche shifts by varying the traits and niche responses of individual populations. Ignoring such effects could substantially underestimate the extent and impact of invasions.

Creation of an engineered APC system to explore and optimize the presentation of immunodominant peptides of major allergens.

We have generated engineered APC to present immunodominant peptides derived from the major aero-allergens of birch and mugwort pollen, Bet v 1142–153 and Art v 125–36, respectively. Jurkat-based T cell reporter lines expressing the cognate allergen-specific T cell receptors were used to read out the presentation of allergenic peptides on the engineered APC. Different modalities of peptide loading and presentation on MHC class II molecules were compared. Upon exogenous loading with allergenic peptides, the engineered APC elicited a dose-dependent response in the reporter T cells and the presence of chemical loading enhancers strongly increased reporter activation. Invariant chain-based MHC class II targeting strategies of endogenously expressed peptides resulted in stronger activation of the reporters than exogenous loading. Moreover, we used Bet v 1 as model allergen to study the ability of K562 cells to present antigenic peptides derived from whole proteins either taken up or endogenously expressed as LAMP-1 fusion protein. In both cases the ability of these cells to process and present peptides derived from whole proteins critically depended on the expression of HLA-DM. We have identified strategies to achieve efficient presentation of allergenic peptides on engineered APC and demonstrate their use to stimulate T cells from allergic individuals.

Evaluation of the association between sensitization to common inhalant fungi and poor asthma control

BackgroundFungi are well-known airborne allergens that are predisposing environmental factors to asthma. Few comparative studies have evaluated sensitization to common inhalant fungi in relation to poor asthma control in patients with asthma. ObjectiveTo evaluate the association between sensitization to individual fungi and asthma control and elucidate the characteristics of patients with poorly controlled asthma sensitized to fungi. MethodsThis cross-sectional study was performed at Showa University Hospital between September 2014 and December 2014. The specific IgE levels for several major aeroallergens, including house dust mites, Japanese cedar, various types of pollen, furry animals, or insects, were measured with a fluorescent enzyme immunoassay in 160 patients with adult asthma. ResultsFungal sensitization was predominant in men with asthma, and it was associated with poor asthma control. Sensitization to house dust mites, Japanese cedar, pollen, furry animals, or insects was not associated with poor asthma control. Logistic regression analyses revealed that patients sensitized to Aspergillus and Penicillium had a significantly increased risk of poor asthma control. More Penicillium IgE–positive patients were men and pet owners compared with Penicillium IgE–negative patients; in addition, Penicillium IgE–positive patients had higher total IgE levels. The Asthma Control Test level was significantly higher in Penicillium IgE–positive patients than in Penicillium IgE–negative patients. However, there were no differences in fractional exhaled nitric oxide, forced vital capacity, and forced expiratory volume in 1 second. Finally, sensitization to Aspergillus, Cladosporium, and Trichophyton were positively correlated with sensitization to Penicillium. ConclusionSensitization to fungi is predominant in men, and it is associated with poor asthma control. In particular, sensitization to Penicillium and Aspergillus is a risk factor for asthma severity. These results have potential relevance in asthma management.

Relation between Poaceae pollen concentrations and meteorological factors during 2000–2010 in Timisoara, Romania

This paper presents the results of Poaceae pollen seasons from 2000–2010 in Timisoara, Romania. Airborne Poaceae pollen concentrations was high. An increasing trend in the annual totals was observed. The longest pollen season was recorded in the year 2000. The period in which the Poaceae pollen count exceeded the threshold value of 30 grains/m&lt;sup&gt;3&lt;/sup&gt; lasted from 9 to 46 days. The present study analyzed the dynamics of pollen seasons in relation to meteorological factors. On the basis of Spearman’s correlation test, the strongest positive correlation was found between the Poaceae pollen counts and temperature; and sunshine hours. Daily average relative humidity, atmospheric pressure and precipitation had a negative effect. A multiple regression analysis was applied to determine how much of the total variance in Poaceae pollen counts can be explained by meteorological parameters. The coefficient of determination ranged from 0.245 to 0.460. Our data illustrate the contrasting effects of temperature, wind, relative humidity and rainfall on the concentration of pollen in the air. The optimum conditions for Poaceae pollen release occur during late spring and early summer. The Poaceae pollen remains one of the major aeroallergens in Timisoara area.

Assessment of sensitivity to common aeroallergens in a Tunisian population

Allergic diseases are common in clinical practice and are considered by the World Health Organization (WHO) as an important health problem (Liu et al. 2010).Worldwide, about 500 million people are affected (15%) with a prevalence of 20-30% in developed countries (Laaidi et al. 2009). This study aimed to identify the major aeroallergens and their prevalence in a population of patients living in a polluted oasis situated in the southwest of Tunisia. A total of 67 patients were admitted to the Department of Pneumology and Oto-rhino-laryngology at Gafsa Hospital between August 2007 and September 2008. They were invited to a health examination including skin-prick test, blood sampling and assessment of specific IgE to several common aeroallergens. Of the 67 patients, only 39 were sensitive to allergens (58.20%), 23 of whom were sensitive to more than one type of allergen (58.97%). The most common aeroallergens were tree and grass pollen (32.96%), followed by animal dander (19.78%), mites (17.58%), herbaceous pollen (12.08%), mould (6.59%), latex (6.59%) and cockroaches (4.39%). Although this study was limited to a modest target population of patients, we did observe significant results that highlight the most frequently detected allergens in the region of Gafsa. These results are in agreement with reports from other studies conducted in other areas.

Grass pollen allergens globally: the contribution of subtropical grasses to burden of allergic respiratory diseases

Grass pollens of the temperate (Pooideae) subfamily and subtropical subfamilies of grasses are major aeroallergen sources worldwide. The subtropical Chloridoideae (e.g. Cynodon dactylon; Bermuda grass) and Panicoideae (e.g. Paspalum notatum; Bahia grass) species are abundant in parts of Africa, India, Asia, Australia and the Americas, where a large and increasing proportion of the world's population abide. These grasses are phylogenetically and ecologically distinct from temperate grasses. With the advent of global warming, it is conceivable that the geographic distribution of subtropical grasses and the contribution of their pollen to the burden of allergic rhinitis and asthma will increase. This review aims to provide a comprehensive synthesis of the current global knowledge of (i) regional variation in allergic sensitivity to subtropical grass pollens, (ii) molecular allergenic components of subtropical grass pollens and (iii) allergic responses to subtropical grass pollen allergens in relevant populations. Patients from subtropical regions of the world show higher allergic sensitivity to grass pollens of Chloridoideae and Panicoideae grasses, than to temperate grass pollens. The group 1 allergens are amongst the allergen components of subtropical grass pollens, but the group 5 allergens, by which temperate grass pollen extracts are standardized for allergen content, appear to be absent from both subfamilies of subtropical grasses. Whilst there are shared allergenic components and antigenic determinants, there are additional clinically relevant subfamily-specific differences, at T- and B-cell levels, between pollen allergens of subtropical and temperate grasses. Differential immune recognition of subtropical grass pollens is likely to impact upon the efficacy of allergen immunotherapy of patients who are primarily sensitized to subtropical grass pollens. The literature reviewed herein highlights the clinical need to standardize allergen preparations for both types of subtropical grass pollens to achieve optimal diagnosis and treatment of patients with allergic respiratory disease in subtropical regions of the world.