Efficacy of Voriconazole against Aspergillus fumigatus Infection Depends on Host Immune Function.

Antifungal therapy can fail in a remarkable number of patients with invasive fungal disease, resulting in significant morbidity worldwide. A major contributor to this failure is that while these drugs have high potency in vitro, we do not fully understand how they work inside infected hosts. Here, we used a transparent larval zebrafish model of Aspergillus fumigatus infection amenable to real-time imaging of invasive disease as an in vivo intermediate vertebrate model to investigate the efficacy and mechanism of the antifungal drug voriconazole. We found that the ability of voriconazole to protect against A. fumigatus infection depends on host innate immune cells and, specifically, on the presence of macrophages. While voriconazole inhibits fungal spore germination and growth in vitro, it does not do so in larval zebrafish. Instead, live imaging of whole, intact larvae over a multiday course of infection revealed that macrophages slow down initial fungal growth, allowing voriconazole time to target and kill A. fumigatus hyphae postgermination. These findings shed light on how antifungal drugs such as voriconazole may synergize with the immune response in living hosts.

Defective cytokine production from monocytes/macrophages of E-beta thalassemia patients in response to Pythium insidiosum infection.

BACKGROUND: Pythium insidiosum has been mainly reported to cause morbidity and mortality in thalassemia patients. P. insidiosum zoospores can germinate to be hyphae within a few hours; therefore, it is difficult to study the initial immune response that P. insidiosum zoospores induce. The present study aims to compare immune responses against P. insidiosum zoospore infection by comparing monocytes/macrophages from thalassemia patients with those from non-thalassemia controls. METHODS: In order to keepP. insidiosum in the zoospore stage in vitro for inoculation, the P. insidiosum zoospores were preserved without germination by treatment with inorganic hypochlorite solution. CD14+ cells were isolated from peripheral blood mononuclear cells of thalassemia and non-thalassemia donors and then left to transition to macrophages. Monocytes/macrophage culture was infected with P. insidiosum zoospores and culture supernatants were subjected to Th1/Th2 multiplex cytokine detection. RESULTS: Our study of cytokine production revealed that the basal level of GM-CSF produced by thalassemia monocytes/macrophages was lower than that observed in monocytes/macrophages of non-thalassemia individuals. Higher GM-CSF and IFN-γ response was also found when cells from non-thalassemia people were stimulated with P. insidiosum zoospores compared to thalassemia cells. It was also found that TNF-α, GM-CSF and IFN-γ productions from monocytes/macrophages of thalassemia patients who received iron chelator treatment were significantly higher than those produced from thalassemia patients without iron chelator treatment. CONCLUSION: For the first time, the present study demonstrates defective immune responses in monocytes/macrophages derived from thalassemia patients in response toP. insidiosum zoospore infection. The results also show an inverse correlation between iron overload and cytokine production in monocytes/macrophages of thalassemia patients. This finding could explain why thalassemia patients are susceptible to P. insidiosum infection.

Aeroallergens in North-Central Nigeria.

INTRODUCTION AND OBJECTIVES: Aeroallergens are airborne organic substances which are responsible for allergenic diseases in hypersensitive individuals. People are exposed to their allergens either directly or after their entrance into the interiors. The spatio-temporal pattern of aeroallergens and their relationship with weather variability in Abuja and Nassarawa, North-Central Nigeria was studied. MATERIALS AND METHODS: Aerosamples were trapped with modified Tauber-like pollen traps. Samples were collected monthly and centrifuged at 2500rpm for 5 min and subjected to acetolysis. Meteorological data were collected from the Nigerian Meteorological Agency. RESULTS AND CONCLUSION: Aeroallergens concentration were unequivocally regulated by weather variables in both locations, indicating the possible use of aeroallergens especially pollen and spores as bio-indicators of weather variations and change. Aeroallergens encountered were fungal spores, pollen, diatom frustules, fern spores, algal cyst/cells in decreasing order of dominance. Among pollen group, Poaceae, Amarathaceae/Chenopodiaceae and Hymenocardia acida dominated. Spores of Smut species, Puccinia, Curvularia and Nigrospora were major contributors among aeromycoflora. Fungal spores morphotype dominated during the rainier months and were major contributors of the aeroallergen spectrum with those belonging to Deuteromycete preponderant. Aeroallergens which were previously identified as triggers of conjunctivitis, asthma, allergic sinusitis and bronchopulmonary allergic diseases were frequently present in both locations. Pollen prevailed more during the harmattan, influenced by northeast trade wind. Pollen component differed and was based on autochthonous source plants, indicating difference in sub-vegetational types.

Short-term effect of outdoor mould spore exposure on prescribed allergy medication sales in Central France.

BACKGROUND: Outdoor moulds are classically associated with exacerbations of asthma. OBJECTIVE: The aim of this paper was to examine nasal allergy morbidity by studying the short-term relationship between mould spore exposure and daily sales of reimbursable anti-allergic treatment in central France. METHODS: The relationship between daily changes in mould concentrations and daily sales obtained from the national healthcare database was analysed with generalized additive models, taking into account confounding factors such as air pollution, weather conditions, pollen counts, and days of the week. RESULTS: During the study, the average total yearly number of treated people was around 10 000 over approximately 230 000 surveyed. The relative risk (95% CI confidence interval) of sales of oral antihistamines with topical treatment associated with an interquartile increase in mould concentration was significant for Cladosporium 1.079 [1.019-1.142] and Aspergillus-Penicillium (Asp-Pen) 1.051 [1.021-1.082] in the whole population. When the influence of age and sex was considered, the relationship was significant only in male children aged 0-12 years and those aged between 13 and 49 years for Cladosporium: 1.256 [1.081-1.460] and 1.151 [1.063-1.245], respectively. The relationship was also significant for Asp-Pen: 1.038 [1.003-1.075] for those aged between 13 and 49 years and 1.056 [1.007-1.108] for adults over 50 years of age. CONCLUSION: The association between prescribed daily sales of oral antihistamines with topical treatment sales is associated with temporal changes to Cladosporium and Aspergillus-Penicillium in the whole population. When the influence of age and sex was considered, these two moulds contributed to prescribed medication sales only in the male general population.

Protein nutrition governs within-host race of honey bee pathogens.

Multiple infections are common in honey bees, Apis mellifera, but the possible role of nutrition in this regard is poorly understood. Microsporidian infections, which are promoted by protein-fed, can negatively correlate with virus infections, but the role of protein nutrition for the microsporidian-virus interface is unknown. Here, we challenged naturally deformed wing virus - B (DWV-B) infected adult honey bee workers fed with or without pollen ( = protein) in hoarding cages, with the microsporidian Nosema ceranae. Bee mortality was recorded for 14 days and N. ceranae spore loads and DWV-B titers were quantified. Amongst the groups inoculated with N. ceranae, more spores were counted in protein-fed bees. However, N. ceranae infected bees without protein-diet had reduced longevity compared to all other groups. N. ceranae infection had no effect on protein-fed bee's longevity, whereas bees supplied only with sugar-water showed reduced survival. Our data also support that protein-feeding can have a significant negative impact on virus infections in insects. The negative correlation between N. ceranae spore loads and DWV-B titers was stronger expressed in protein-fed hosts. Proteins not only enhance survival of infected hosts, but also significantly shape the microsporidian-virus interface, probably due to increased spore production and enhanced host immunity.

Aeroallergens, atopy and allergic rhinitis in the Middle East.

The literature on the nature and prevalence of indoor and/or outdoor aeroallergens, atopy and symptoms of rhinitis and asthma in the Middle East region (defined here as Bahrain, Egypt, Iran, Iraq, Israel, Jordan, Kuwait, Lebanon, Oman, Palestine, Qatar, Kingdom of Saudi Arabia - KSA, Syria, United Arab Emirates and Yemen) was reviewed. Although documentation was poor in all countries other than Iran and the KSA, a wide range of "global" and "local" aeroallergens (grass, weed and tree pollens, fungal spores, insect allergens, dander, and house dust mites) has been observed across the region. The prevalence of current self-reported or parent-reported symptoms of rhinitis ranged from 9% to 38%. Researchers have suggested that the high atopy rates and self-reported rhinitis rates are associated with an on-going shift towards a "western" lifestyle.

Projections of the effects of climate change on allergic asthma: the contribution of aerobiology.

Climate change is unequivocal and represents a possible threat for patients affected by allergic conditions. It has already had an impact on living organisms, including plants and fungi with current scenarios projecting further effects by the end of the century. Over the last three decades, studies have shown changes in production, dispersion and allergen content of pollen and spores, which may be region- and species-specific. In addition, these changes may have been influenced by urban air pollutants interacting directly with pollen. Data suggest an increasing effect of aeroallergens on allergic patients over this period, which may also imply a greater likelihood of the development of an allergic respiratory disease in sensitized subjects and exacerbation of symptomatic patients. There are a number of limitations that make predictions uncertain, and further and specifically designed studies are needed to clarify current effects and future scenarios. We recommend: More stress on pollen/spore exposure in the diagnosis and treatment guidelines of respiratory and allergic diseases; collection of aerobiological data in a structured way at the European level; creation, promotion and support of multidisciplinary research teams in this area; lobbying the European Union and other funders to finance this research.

Allergens and thunderstorm asthma.

Thunderstorm-related asthma is increasingly recognized in many parts of the world. This review focuses on important advances in the understanding of the mechanism of the role of allergens, in particular fungal spores such as Alternaria, in asthma epidemics associated with thunderstorms. From our observations, we have proposed that the prerequisites for this phenomenon are as follows: 1) a sensitized, atopic, asthmatic individual; 2) prior airway hyperresponsiveness before a sudden, large allergen exposure; 3) a large-scale thunderstorm with cold outflow occurring at a time and location during an allergen season in which large numbers of asthmatics are outdoors; and 4) sudden release of large amounts of respirable allergenic fragments, particularly fungal spores such as Alternaria.

Temporal clinical exacerbation of summer pasture-associated recurrent airway obstruction and relationship with climate and aeroallergens in horses.

OBJECTIVE: To describe the seasonal pattern of clinical exacerbation of summer pasture-associated recurrent airway obstruction (SPA-RAO) in relation to climate and aeroallergens in horses. ANIMALS: 19 horses with SPA-RAO and 10 nonaffected horses. PROCEDURES: Daily examinations were performed on all horses while they were kept on pasture for 3 years. Onset and progression of clinical exacerbation based on a clinical score of respiratory effort were evaluated in relation to changes in maximum temperature, minimum temperature, mean temperature, maximum dew-point temperature, minimum dew-point temperature, and delta dew-point temperature. Seasonal pattern of clinical exacerbation was evaluated in relation to aeroallergen counts (20 types of fungal spores and 28 types of pollen). RESULTS: Seasonal pattern of clinical exacerbation of SPA-RAO was associated with increases in temperature (heat) and dew-point temperature (humidity), counts of fungal spores, and counts of grass pollen grains. Seasonal pattern of clinical exacerbation paralleled and was associated with increases in counts of specific types of fungal spores, particularly Basidiospore, Nigrospora, and Curvularia spp. CONCLUSIONS AND CLINICAL RELEVANCE: Although a causal relationship could not be determined, the seasonal pattern of clinical exacerbation of SPA-RAO was associated with hot and humid conditions and high environmental counts for fungal spores and grass pollen grains. It is not known yet whether these are aeroallergens that cause clinical exacerbation of the disease.

Successful treatment of hypersensitivity pneumonitis caused by Grifola frondosa (Maitake) mushroom using a HFA-BDP extra-fine aerosol.

We successfully treated a patient with occupational hypersensitivity pneumonitis (HP) caused by Grifola frondosa (Maitake) mushroom spore with an extra-fine aerosol corticosteroid; beclomethasone dipropionate (BDP) dissolved in hydrofluoroalkane-134a (HFA). A 49-year-old woman developed respiratory symptoms 3 months after beginning work on a mushroom farm. She was diagnosed as HP based on radiological and serological findings. Oral prednisolone therapy improved her HP and she returned to the same farm. Her HP relapsed after 5 months, and daily 400 microg of HFA-BDP was administered with gradual improvement. An extra-fine particle inhaled corticosteroid might reach appropriate alveoli to be effective therapy for mild HP.

[Treatment of allergy to mould spores]. / Leczenie uczulen na zarodniki grzybów plesniowych.

The treatment of mould allergy is discussed in this article. The specific immunotherapy should be especially considered in this group of patients.

Hypersensitivity to molds in New York City in adults who have asthma.

Molds have been linked epidemiologically to asthma as a key aeroallergen in several studies. Other allergens such as cockroach have been linked to asthma in New York City (NYC). To our knowledge, however, the pattern of mold hypersensitivity has never been examined systematically in the NYC area. Thus, we sought to determine the association between mold hypersensitivity and asthma in a large group of ambulatory patients evaluated for allergic disease for the years 1993 through 2001 at a single medical center. Serological testing for mold-specific immunoglobulin E (IgE) as well as IgE specific for other aeroallergens was performed and the associations between allergen-specific IgE and the presence of asthma were examined using bivariate and multivariate analysis. Factor analysis showed that three distinct groupings of aeroallergen-specific IgE existed within the panel of allergens used. Group 1 consisted of cat dander and dust mites (Dermatophagoides farinae). Group 2 consisted of tree, grass, and ragweed pollen. Group 3 consisted of the Deuteromycetes molds, Alternaria tenuis, Aspergillus fumigatus, and Cladosporium herbarum. Patients with asthma had a highly significant increase in the incidence of hypersensitivity to cat/dust mites and to the molds. Multivariate analysis showed that the presence of hypersensitivity to either A. tenuis or C. herbarum had a significant independent association with asthma after adjustment for cat/dust mite hypersensitivity and after adjustment for other clinical factors. On the other hand, pollen hypersensitivity was not associated independently with asthma. Mold hypersensitivity was strongly correlated with hypersensitivity to cat or dust mites in patients who did not have asthma but not in patients who did have asthma. In the NYC area, recent pollen and spore counts show that mold spores are measurable in at least 75% of the year. Thus it is conceivable that mold hypersensitivity plays a contributing and independent role in initiating or perpetuating the allergic response in patients with asthma in the New York area.

The role of fungal spores in thunderstorm asthma.

STUDY OBJECTIVES: To document the existence and investigate the etiology of "thunderstorm asthma," which has been reported sporadically over the past 20 years. DESIGN: We assessed the relationship between thunderstorms, air pollutants, aeroallergens, and asthma admissions to a children's hospital emergency department over a 6-year period. RESULTS: During thunderstorm days (n = 151 days) compared to days without thunderstorms (n = 919 days), daily asthma visits increased from 8.6 to 10 (p < 0.05), and air concentrations of fungal spores doubled (from 1,512 to 2,749/m(3)), with relatively smaller changes in pollens and air pollutants. Daily time-series analyses across the 6 years of observation, irrespective of the presence or absence of thunderstorms, demonstrated that an increase in total spores, equivalent to its seasonal mean, was associated with a 2.2% (0.9% SE) increase in asthma visits. CONCLUSIONS: Our results support a relationship between thunderstorms and asthma, and suggest that the mechanism may be through increases in spores that exacerbate asthma. Replication in other climates is suggested to determine whether these findings can be generalized to other aeroallergen mixes.

Differences in concentrations of allergenic pollens and spores at different heights on an agricultural farm in West Bengal, India.

The aim of the study was to assess the vertical profile of the major airborne pollen and spore concentration in the lower heights (up to six meters) and to check their allergenic potential causing respiratory allergy in agricultural workers. The study was conducted using rotorod samplers mounted at different heights at weekly intervals for two consecutive years (November 1997-October 1999). The major pollen grains and fungal spores (from mass culture) were collected in bulk and studied by skin-prick tests to detect allergenicity. Of the recorded pollen, 10 major and perennial types (e.g., Poaceae, Cheno-Amaranthaceae, Cyperaceae, Areca, etc.) were considered for comparative analyses. The tree pollen count showed more or less good correlation with increasing heights, whereas herb/shrub members are dominant at lower heights during all the three seasons (winter, summer and rains). The 10 major and perennial fungal spore types included Aspergilli group, Cladosporium, Nigrospora, etc. The smaller spores were dominant at greater heights and larger spores and conidia were more prevalent at lower levels. The total spore count was higher just after the rainy season during winter. In terms of allergenicity, Saccharum officinarum (sugar cane) of Poaceae, showed highest reactivity (70.58%) in skin test carried out in 189 adult agricultural field workers with respiratory disorders living inside the study area. Among fungal spores, Aspergillus japonicus was the strongest allergen, evoking 74.07% positive reactions. Drechslera oryzae, the pathogen causing brown spot of rice was also found to be a potent allergen.

Therapeutic effect of IL-13 immunoneutralization during chronic experimental fungal asthma.

IL-13 and IL-4 are key contributors to the asthmatic phenotype. The temporal role of these cytokines in airway function, inflammation, and remodeling were assessed in a chronic murine model of Asperigillus fumigatus-induced allergic asthma. IL-13 and IL-4 protein levels were significantly elevated by 30 days after conidia challenge in A. fumigatus-sensitized mice. Furthermore, IL-13Ralpha1 mRNA expression was significantly elevated 7 days after conidia challenge and remained elevated until day 21. In contrast, IL-13Ralpha2 mRNA expression, although constitutively expressed in naive lung, was absent in the lungs of A. fumigatus-sensitized mice both before and after conidia challenge. Membrane-bound IL-4R mRNA expression was significantly elevated 7 days after conidia challenge; however, soluble IL-4R mRNA expression was increased 30 days after conidia challenge. Immunoneutralization of IL-13 between days 14 and 30 or days 30 and 38 after fungal sensitization and challenge significantly attenuated airway hyperresponsiveness, collagen deposition, and goblet cell hyperplasia at day 38 after conidia challenge; however, the effects of IL-4 immunoneutralization during the same time periods were not as marked. IFN-gamma and IL-12 release after Aspergillus Ag restimulation was elevated from spleen cells isolated from mice treated with IL-4 anti-serum compared with IL-13 anti-serum or normal rabbit serum-treated mice. This study demonstrates a pronounced therapeutic effect of IL-13-immunoneutralization at extended time points following the induction of chronic asthma. Most importantly, these therapeutic effects were not reversed following cessation of treatment, and IL-13 anti-serum treatment did not alter the systemic immune response to Ag restimulation, unlike IL-4 immunoneutralization. Therefore, IL-13 provides an attractive therapeutic target in allergic asthma.

Environmental contributions to allergic disease.

The environment is a major contributor to allergic disease, and great effort is being expended to identify the chemical pollutants and allergens that make a significant impact. Exposure to high levels of ozone, sulfur dioxide, nitrogen dioxide, and diesel exhaust particles is known to reduce lung function. Studies continue to delineate the role of these particles as adjuvants and carriers of allergens into the respiratory system. Current studies also show the exacerbation of allergic disease through fungal spore inhalation and continue to document the role of pollen in allergic rhinitis. Pollen also was recently associated with asthma epidemics, especially after thunderstorms. Forecasting models currently are being developed that predict the trajectories of pollen dispersal and may allow increased avoidance of dangerous outdoor conditions.

A new method for simultaneous immunodetection and morphologic identification of individual sources of pollen allergens.

BACKGROUND: Exposure to outdoor allergens has commonly been estimated by collecting airborne particles with a Hirst-type spore trap and then using morphologic criteria to identify the intact pollen grains and fungal spores that are recognized as allergen sources. Several antibody-based blotting or fixation methods have also been developed that enable the counting of amorphous airborne particles carrying allergen, but none of these methods allow the ready association of the released allergen with the morphologically identifiable particle of origin. A method has been developed that uses pressure-sensitive adhesive tape to sample the airborne particles and then allows the immunoidentification of the specific particles that are the allergen sources. OBJECTIVE: Our purpose was to visualize and immunostain the particles carrying pollen allergen that are collected with a volumetric spore trap. METHODS: A Burkard sampler was used to collect airborne particles onto pressure-sensitive adhesive tapes. The particles were permanently fixed between the tape and a protein-binding membrane when the tape was laminated with the membrane. Allergens that elute from the particles onto the membrane were detected with a range of antibodies. Both the particle and associated immunostained allergen were viewed through the transparent tape for final microscopic identification. RESULTS: Polyclonal and monoclonal antibodies and IgE from allergic patients stained allergens in the periphery of particles collected on the tapes. Individual pollen grains and paucimicronic particles were seen with halos of immunostained allergen surrounding them. When IgE was used, the density of immunostaining in the halo surrounding Lolium perenne pollen grains was found to be proportional to the level of Lolium-specific IgE. The method is highly sensitive and can be used to detect different airborne particles that carry allergen. Both the particle and the immunostaining can be subjected to a range of simple measurement techniques. CONCLUSION: Individual particles carrying allergens and antigens were visualized. These particles included intact pollen grains, paucimicronic particles, and fungal spores.