The Brown Roll-Rim Mushroom, Paxillus involutus (Agaricomycetes), as a Promising Biomedical Research Resource.

The brown roll-rim mushroom (Paxillus involutus) quickly produces biomass in nature, although, being a mycorrhizal fungus, it is rather poorly maintained in culture. Information about its toxic properties is controversial. Until the mid-20th century, the species was considered as an edible fungus; however, data later accumulated regarding its poisonous properties, leading to the term "Paxillus syndromeP. involutus. Since mushrooms can have quite a few unidentified antigens complementary to B-lymphocyte receptors, this is a hidden danger of using unfractionated mushroom raw materials for preventive and oncotherapy purposes, and we hope that this article stimulates immunological groups worldwide to identify the "X" antigen related to the Paxillus syndrome. Oncotherapy effects of the known bioactive complexes of P. involutus are associated with a specific inhibition of some growth receptors of the cancer cell, whereas experimentation with purified substances of P. involutus and various families of growth receptors of cancer cell has good prospects. A clear speciation is fixing within the P. involutus complex. The key for identification of species of P. involutus complex is given and cultural characteristics of P. involutus strains kept at Komarov Botanical Institute Basidiomycetes Culture Collection are presented.

Preclinical safety and immunological efficacy of Alternaria alternata polymerized extracts.

INTRODUCTION: Alternaria alternata is a widespread fungi whose allergy is a risk factor for asthma development. The use of a polymerized allergen extract (allergoid) may be safer than native extract based treatments while maintaining efficacy. The objective of this study was to characterize biochemically and immunochemically a new Alternaria alternata allergoid. METHODS: Characterization of native and allergoid extracts was performed by determination of protein content, protein and allergenic profile, biological potency, identification of Alternaria allergens, and Alt a 1 quantification. Safety was evaluated in toxicological assays (Ames test, limit test, and fish embryo acute toxicity test in zebrafish, and maximum tolerated dose and Dose-range finding study in rats). Efficacy was evaluated as the capacity to induce IgG antibodies that block IgE-binding to the allergen and cytokine induction (IFN-γ, IL-4, IL-6, IL-10, and TNF-α) in PBMC from atopic donors. RESULTS: Protein and antigenic profiles showed significant modification of the depigmented allergoid with respect to the native extract, inducing a lower IgE binding capacity. Alt a 1, Alt a 3, Alt a 6, and Alt a 8 allergen sequences were identified in the polymer. No toxicological nor genotoxicity effects were observed. The polymer induced IgG antibodies that blocked human IgE binding epitopes, and it induced higher IL-10 levels and similar levels of the other cytokines than native extract in PBMC. CONCLUSIONS: This new A. alternata allergoid could be an effective immunotherapy treatment leading to cytokine stimulation and inducing synthesis of IgG antibodies able to block IgE binding to the allergen. In addition, no toxicological effect was observed, and it may be safer than native extract due to its lower IgE binding capacity and cytokine induction that suggest tolerance induction via T cell shift to Treg (IL-10).

Eosinophil persistence in vivo and sustained viability ex vivo in response to respiratory challenge with fungal allergens.

BACKGROUND: Eosinophils are immunomodulatory leucocytes that contribute to the pathogenesis of Th2-driven asthma and allergic lung diseases. OBJECTIVE: Our goal was to identify unique properties of eosinophils recruited to the lungs and airways of mice in response to challenge with asthma-associated fungal allergens. METHODS: Mice were challenged intranasally on days 0, 3 and 6 with a filtrate of Alternaria alternata. Recruited eosinophils were enumerated in bronchoalveolar lavage fluid. Eosinophils were also isolated from lungs of mice sensitized and challenged with Aspergillus fumigatus and evaluated ex vivo in tissue culture. RESULTS: Eosinophils persist in the airways for several weeks in response to brief provocation with A. alternata in wild-type, Gm-csf- and eotaxin-1-gene-deleted mice, while eosinophils are recruited but do not persist in the absence of IL-13. Eosinophils isolated from the lungs A. alternata-challenged mice are cytokine-enriched compared to those from IL5tg mice, including 800-fold higher levels of eotaxin-1. Furthermore, eosinophils from the lungs and spleen of fungal allergen-challenged wild-type mice are capable of prolonged survival ex vivo, in contrast to eosinophils from both untreated and fungal allergen-challenged IL5tg mice, which undergo rapid demise in the absence of exogenous cytokine support. TNF-α (but not IL5, IL-3, eotaxin-1 or GM-CSF) was detected in supernatants of ex vivo eosinophil cultures from the lungs of fungal allergen-challenged wild-type mice. However, neither TNF-α gene deletion nor anti-TNF-α neutralizing antibodies had any impact sustained eosinophil survival ex vivo. CONCLUSION AND CLINICAL RELEVANCE: Eosinophils are phenotypically and functionally heterogeneous. As shown here, eosinophils from fungal allergen-challenged wild-type mice maintain a distinct cytokine profile, and, unlike eosinophils isolated from IL5tg mice, they survive ex vivo in the absence of exogenous pro-survival cytokine support. As treatments for asthma currently in development focus on limiting eosinophil viability via strategic cytokine blockade, the molecular mechanisms underlying differential survival merit further investigation.

Influences of large sets of environmental exposures on immune responses in healthy adult men.

Environmental factors have long been known to influence immune responses. In particular, clinical studies about the association between migration and increased risk of atopy/asthma have provided important information on the role of migration associated large sets of environmental exposures in the development of allergic diseases. However, investigations about environmental effects on immune responses are mostly limited in candidate environmental exposures, such as air pollution. The influences of large sets of environmental exposures on immune responses are still largely unknown. A simulated 520-d Mars mission provided an opportunity to investigate this topic. Six healthy males lived in a closed habitat simulating a spacecraft for 520 days. When they exited their "spacecraft" after the mission, the scenario was similar to that of migration, involving exposure to a new set of environmental pollutants and allergens. We measured multiple immune parameters with blood samples at chosen time points after the mission. At the early adaptation stage, highly enhanced cytokine responses were observed upon ex vivo antigen stimulations. For cell population frequencies, we found the subjects displayed increased neutrophils. These results may presumably represent the immune changes occurred in healthy humans when migrating, indicating that large sets of environmental exposures may trigger aberrant immune activity.

Evaluation of the Antigenotoxic Effects of the Royal Sun Mushroom, Agaricus brasiliensis (Higher Basidiomycetes) in Human Lymphocytes Treated with Thymol in the Comet Assay.

The aim of this investigation was to evaluate the possible protective activity of Agaricus brasiliensis (=A. blazei sensu Murrill) ethanol extract against thymol-induced DNA damage in human lymphocytes. Before we studied the possible interaction of thymol and A. brasiliensis extract, each component was tested in the comet assay. Thymol significantly increased DNA damage in human lymphocytes at higher concentrations (20, 50, 100, 150, and 200 µg/mL), whereas no genotoxic effect of A. brasiliensis ethanol extract was observed. In simultaneous treatment with thymol (200 µg/mL) and A. brasiliensis ethanol extract (50, 100, 150, and 200 µg/mL), the latter failed to reduce a thymol-induced DNA damaging effect regardless of the applied concentrations. To confirm that thymol induces DNA damage via reactive oxygen species, we performed cotreatment with quercetin. Cotreatment with quercetin (100 and 500 µmol/L) significantly reduced DNA damage caused by thymol (200 µg/mL), indicating that thymol exhibits genotoxicity mainly through induction of reactive oxygen species.

Assessing the allergenic potential of molds found in water-damaged homes in a mouse model.

Damp/moldy indoor environments, which have resulted from flooding events and may increase as a result of climate change, have been associated with asthma exacerbation. Certain molds found in significantly higher or lower concentrations in asthmatics' homes compared to control homes have been categorized as Group 1 (G1) and Group 2 (G2) molds, respectively. We have compared the allergic potential of selected G1/G2 molds to house dust mite (HDM) in a mouse model. BALB/c mice were exposed to mold (0-80 µg) or HDM (20 µg) extract by intratracheal aspiration either 4X over 4 weeks (allergenicity) or 1X (non-specific responses). Airflow limitation (methacholine challenge) was measured (Day 1) and serum and bronchoalveolar lavage fluid were collected (Day 2) after the final exposure. The G1 molds induced low-to-moderate responses and required higher doses to achieve antigen-specific IgE results similar to those induced by HDM. Compared to HDM responses, the G2 mold in this study required lower doses to induce a similar response. Acute exposure responses suggest some molds may exacerbate asthmatic responses. These studies demonstrate the differing capacities of molds to induce responses associated with allergic asthma, including differences in the threshold dose for allergy induction. Therefore, molds must be evaluated individually for allergic/asthmatic potential. These studies along with our previous studies with G1 (Stachybotrys chartarum)/G2 (Penicillium chrysogenum) molds suggest that the G1/G2 categorization is not indicative of allergic potential but they do not preclude this categorization's utility in determining unhealthy building dampness.

Tropospheric winds from northeastern China carry the etiologic agent of Kawasaki disease from its source to Japan.

Evidence indicates that the densely cultivated region of northeastern China acts as a source for the wind-borne agent of Kawasaki disease (KD). KD is an acute, coronary artery vasculitis of young children, and still a medical mystery after more than 40 y. We used residence times from simulations with the flexible particle dispersion model to pinpoint the source region for KD. Simulations were generated from locations spanning Japan from days with either high or low KD incidence. The postepidemic interval (1987-2010) and the extreme epidemics (1979, 1982, and 1986) pointed to the same source region. Results suggest a very short incubation period (<24 h) from exposure, thus making an infectious agent unlikely. Sampling campaigns over Japan during the KD season detected major differences in the microbiota of the tropospheric aerosols compared with ground aerosols, with the unexpected finding of the Candida species as the dominant fungus from aloft samples (54% of all fungal strains). These results, consistent with the Candida animal model for KD, provide support for the concept and feasibility of a windborne pathogen. A fungal toxin could be pursued as a possible etiologic agent of KD, consistent with an agricultural source, a short incubation time and synchronized outbreaks. Our study suggests that the causative agent of KD is a preformed toxin or environmental agent rather than an organism requiring replication. We propose a new paradigm whereby an idiosyncratic immune response, influenced by host genetics triggered by an environmental exposure carried on winds, results in the clinical syndrome known as acute KD.

Occupational causes of sarcoidosis.

PURPOSE OF REVIEW: Sarcoidosis, the multiorgan granulomatous disease of unknown cause, remains mysterious. Several important investigations in the past 2 years add to the accumulating evidence for both occupational and environmental causes of granulomatous inflammation. RECENT FINDINGS: This review considers the most recent studies that contribute to the hypothesis that sarcoidosis occurs when individuals are exposed to foreign antigens and to inorganic particulates that promote inflammation. Major recent findings, such as those emerging from the study of World Trade Center responders, the study of nanoparticles, and cases of work-associated sarcoidosis, support the probability that occupational, as well as environmental, exposures to inflammatory stimuli trigger sarcoidosis-like illness. Major recent studies of microbially rich indoor environments, including moldy indoor workplaces and mycobacterially contaminated settings, contribute to the evidence that a variety of microbial antigens serve as targets for the hypersensitivity immune response in an inflammatory milieu. SUMMARY: There is increasing evidence that sarcoidosis can occur in workplace settings in which there is exposure to both foreign antigens and inorganic triggers of inflammation that promote an exuberant granulomatous immune response. It is likely that sarcoidosis has more than one cause.

The protease allergen Pen c 13 induces allergic airway inflammation and changes in epithelial barrier integrity and function in a murine model.

Fungal allergens are associated with the development of asthma, and some have been characterized as proteases. Here, we established an animal model of allergic airway inflammation in response to continuous exposure to proteolytically active Pen c 13, a major allergen secreted by Penicillium citrinum. In functional analyses, Pen c 13 exposure led to increased airway hyperresponsiveness, significant inflammatory cell infiltration, mucus overproduction, and collagen deposition in the lung, dramatically elevated serum levels of total IgE and Pen c 13-specific IgE and IgG1, and increased production of the Th2 cytokines IL-4, IL-5, and IL-13 by splenocytes stimulated in vitro with Pen c 13. To examine the mechanisms involved in the regulation of allergenicity by Pen c 13, we performed two-dimensional fluorescence difference gel electrophoresis analysis combined with nano-LC-MS/MS, followed by bioinformatics analysis to identify potential targets that associated with allergic inflammation, which suggested that galectin-3 and laminin might be involved in novel pathogenic mechanisms. Finally, we focused on junctional proteins between cells, because, in addition to opening of the epithelial barrier by environmental proteases possibly being the initial step in the development of asthma, these proteins are also associated with actin rearrangement. Taken together, our findings indicate that Pen c 13 exposure causes junctional structure alterations and actin cytoskeletal rearrangements, resulting in increased permeability and airway structural changes. These effects probably change the lung microenvironment and foster the development of allergic sensitization.

Microarray-based identification of novel biomarkers in asthma.

Bronchial asthma is a complicated and diverse disorder affected by genetic and environmental factors. It is widely accepted that it is a Th2-type inflammation originating in lung and caused by inhalation of ubiquitous allergens. The complicated and diverse pathogenesis of this disease yet to be clarified. Functional genomics is the analysis of whole gene expression profiling under given condition, and microarray technology is now the most powerful tool for functional genomics. Several attempts to clarify the pathogenesis of bronchial asthma have been carried out using microarray technology, providing us some novel biomarkers for diagnosis, therapeutic targets or understanding pathogenic mechanisms of bronchial asthma. In this article, we review the outcomes of these analyses by the microarray approach as applied to this disease by focusing on the identification of novel biomarkers.

Hydrolase and oxidoreductase activities in peripheral blood lymphocytes in combined exposure to biological allergens and sulfur dioxide.

Differences in the metabolic status of peripheral blood lymphocytes were observed after exposure of intact guinea pigs and animals sensitized with biological allergens to sulfur dioxide. When sensitization was complicated by chemical exposure, enzyme activities in lymphocytes depended on the type of allergen and degree of hypersensitivity.

Development of a murine model of chronic rhinosinusitis.

OBJECTIVE: The aim of this study was to develop a mouse model of chronic eosinophilic rhinosinusitis. STUDY DESIGN: Mice were sensitized to Aspergillis fumigatus (Af) extract by intraperitoneal injection. The animals subsequently received nasal challenges with Af extract 3 times per week for 12 weeks. Sinonasal complexes were studied histologically by the study otolaryngologists and pathologists to characterize the inflammatory response. SETTING: Animal care facility at an academic institution. RESULTS: A chronic eosinophilic inflammatory response was evoked in all study animals. Statistical analysis was performed for inflammation, secretory cell hyperplasia, mast cells, and eosinophils. There were very significant differences (P<0.0005) between control and study mice in all categories. CONCLUSION: Prolonged nasal challenge of Af extract creates an inflammatory response in murine nasal mucosa that mimics human chronic eosinophilic rhinosinusitis. SIGNIFICANCE: A murine model for chronic rhinosinusitis is reported that may facilitate future investigations into disease pathophysiology. EBM RATING: B-2.

The fungal biopesticide Metarhizium anisopliae has an adjuvant effect on the allergic response to ovalbumin in mice.

The parasitic fungus, Metarhizium anisopliae, is non-pathogenic to humans and licensed for indoor control of cockroach infestation. An important reason for the elimination of this vermin is that sensitisation to cockroaches is associated with asthma. Previously M. anisopliae has been shown to cause allergic- and asthma-like responses in mice and in the present study we have examined the adjuvant activity of M. anisopliae on the allergic response to the model allergen ovalbumin (OVA) in a mouse model. Levels of OVA-specific IgE, IgG1 and IgG2a in serum were measured and the weight and cell number of the excised popliteal lymph node were determined. Mice primed with mycelium+OVA and boosted with OVA had increased anti-OVA IgE and IgG1 levels compared with mice primed with OVA alone or mycelium. Priming with M. anisopliae (as mycelium or MACA) increased weight or cell number of the excised PLNs. These results suggest that M. anisopliae has the ability to increase an allergic response to an allergen and consequently, may worsen allergy in susceptible individuals.

Effect of the K+(ATP) channel opener, KCO912, on baseline and allergen induced airway hyperresponsiveness in allergic rabbits.

The effect of the adenosine triphosphate sensitive K+ (K(ATP)) channel opener (3S,4R)-3,4-dihydro-3-hydroxy-2,2-dimethyl-4-(2-oxo-1-piperidinyl)-N-phenyl-1-benzopyran-6-sulphonamide (KCO912) on airway hyperresponsiveness induced using either a combination of allergen immunization (i.p.) followed by aerosol allergen challenge or immunization alone was investigated. Rabbits were immunized with Alternaria tenuis for the first 3 months of life. Airway responsiveness to histamine was measured 24 h before and after A. tenuis aerosol challenge. Fifteen minutes before the second challenge, rabbits were pre-treated with 10 microg of KCO912 or vehicle by inhalation. Allergen challenge induced airway hyperresponsiveness in vehicle pre-treated rabbits and pre-treatment with KCO912 abolished the airway hyperresponsiveness. The effect of KCO912 (10 microg) or vehicle on baseline airway hyperresponsiveness to the adenosine A(1) receptor agonist, cyclopentyl adenosine (CPA), induced by immunization with A. tenuis alone, was also assessed. Rabbits, immunized with A. tenuis alone, exhibited baseline airway hyperresponsiveness as demonstrated by an increase in airway resistance to CPA. Treatment with KCO912 did not alter the allergen-induced airway responsiveness to CPA. This study demonstrates that KCO912 can inhibit allergen-induced exacerbations of airway hyperresponsiveness.

An extract of Stachybotrys chartarum causes allergic asthma-like responses in a BALB/c mouse model.

Environmental exposure to Stachybotrys chartarum has been associated with multiple adverse health effects in humans. The goal of this study was to assess soluble components of this fungus for their ability to cause an asthma-like response in a BALB/c mouse model. Five isolates of S. chartarum were combined and extracted to form a crude antigen preparation (S. chartarum extract 1 [SCE-1]). Female BALB/c mice were sensitized by involuntary aspiration of SCE-1 and subsequently reexposed at 2, 3, and 4 weeks. To distinguish immune from nonspecific inflammatory effects, mice were exposed to 3 doses of Hanks' balanced salt solution (HBSS) and a final dose of SCE-1; or to 4 doses of bovine serum albumin (BSA) as a negative control protein. Serum and bronchoalveolar lavage fluid (BALF) were collected before the fourth aspiration (Day 0), and at Days 1, 3, and 7 following the final exposure, and lungs were fixed for histopathological examination. SCE-1-exposed mice displayed increased BALF total protein on Days 0, 1, and 3 and increased lactate dehydrogenase (LDH) at Days 1 and 3 only, compared to HBSS controls. BALF total cell numbers were elevated on each day, and differential counts of BALF cells showed neutrophilia on Day 1, marked eosinophilia on all days, and increased numbers of lymphocytes at Days 1, 3, and 7. Serum and BALF total IgE levels were elevated at all days, and BALF IL-5 levels were greatly increased (7-fold) on Day 1. Mice exposed to a single dose of SCE-1 exhibited inflammatory responses but not allergic responses, while BSA-treated mice showed neither inflammatory nor allergic responses. Histopathology confirmed the biochemical findings. Barometric whole-body plethysmography was performed 10 min prior to (baseline) and one h following each aspiration exposure in a second group of mice, to assess immediate respiratory responses. Airway hyperresponsiveness to increasing concentrations of nebulized methacholine (MCh) was assessed on Days 1 and 3 following the fourth aspiration exposure. Exposure to HBSS or BSA did not alter baseline enhanced pause (PenH) values or PenH following the aspiration exposures, nor did it cause an increase in airway responsiveness to MCh. Exposure to SCE-1 resulted in a 4.7-fold increase in PenH over baseline after the third exposure, increasing to 5.6-fold after the final exposure, and increased responsiveness to a 32 mg/ml MCh aerosol challenge. We conclude that multiple respiratory exposures to SCE-1 cause responses typical of allergic airway disease in this mouse model. However, BSA was nonallergenic and did not generate respiratory physiological responses when administered by aspiration.

Intranasal delivery of a truncated recombinant human SP-D is effective at down-regulating allergic hypersensitivity in mice sensitized to allergens of Aspergillus fumigatus.

C57BL/6 mice were sensitized to Aspergillus fumigatus 1-week culture filtrate, which is rich in the non-glycosylated allergen Asp f1, a major allergen in allergic bronchopulmonary aspergillosis (ABPA). A comparison of the effect of treatment of allergen challenged mice by intranasal administration of a 60-kDa truncated recombinant form of human SP-D (rfhSP-D) or recombinant full length SP-A (rhSP-A) was undertaken. Treatment with rfhSP-D produced significant reduction in IgE, IgG1 and peripheral blood eosinophilia and treatment with rfhSP-D, but not rhSP-A resulted in a significant reduction in airway hyperresponsiveness as measured by whole body plethysmography. Lung histology revealed less peribronchial lymphocytic infiltration in mice treated with rfhSP-D. Intracellular cytokine staining of spleen homogenates showed increases in IL-12 and IFN-gamma and decrease in IL-4. The level of endogenous mouse SP-D was elevated sixfold in the lungs of sensitized mice and was not affected by treatment with rfhSP-D. Taken with our previous studies, with a BALB/c mouse model of ABPA using a 3-week A. fumigatus culture filtrate, the present results show that rfhSP-D can suppress the development of allergic symptoms in sensitized mice independent of genetic background and using a different preparation of A. fumigatus allergens.

Allergic responses to the biopesticide Metarhizium anisopliae in Balb/c mice.

Metarhizium anisopliae is used as a microbial pesticide to control cockroaches and other insects. M. anisopliae has demonstrated neither infectivity nor toxicity in mammals. However, allergenicity has not been assessed. M. anisopliae is a prototype for other organisms released into the environment for pesticide or other beneficial applications. Hence this study is part of an effort to develop methods for screening such organisms for allergenic potential. Soluble factors from fungal components were combined in equal protein amounts to form a crude fungal antigen (MACA). Balb/c mice were intratracheally (IT) challenged with 25 micrograms fungal antigen 13 days post intraperitoneal sensitization with the fungal antigen in alhydrogel adjuvant. Additionally, mice were sensitized with adjuvant alone or chitin media in adjuvant as experimental controls. Serum and bronchoalveolar lavage fluid (BALF) were harvested prior to challenge and at 1 and 7 days post IT challenge (DPIT). These mice exhibited immune and pulmonary inflammatory responses to MACA characteristic of allergy. Total serum IgE for antigen-sensitized animals increased 7.6- and 14.7-fold over that for chitin media and adjuvant controls, respectively, at 7 DPIT. Less striking increases were seen at 24 DPIT and prior to challenge. BALF IL-4 was dramatically elevated only in MACA-sensitized and challenged mice and only at 1 DPIT. Additionally, there was a dose-dependent increase in BALF eosinophils from MACA-sensitized mice at both 1 and 7 DPIT. While lymphocyte counts were increased for all treatment groups at 1 DPIT, by 7 DPIT lymphocyte counts for MACA-sensitized mice only were significantly elevated compared to controls. Pulmonary inflammation, edema, and cell damage were apparent at 1 DPIT (25 micrograms MACA), as indicated by a neutrophilic influx and elevated levels of total protein and LDH, in both sensitized and control groups. These effects were significantly decreased, but not eliminated by reduction of the challenge dose to either 10 or 5 micrograms MACA. While BALF IL-4 was also reduced at the lower challenge doses, eosinophilia and total IgE were unchanged. The data suggest that the crude fungal extract MACA contains one or more potent allergens and that total IgE may be useful in the identification of the allergen(s).

Identification and evaluation of a major cytotoxin of A. fumigatus.

Aspergillus fumigatus is a highly pathogenic fungus causing a wide spectrum of diseases in immunocompromised as well as immunocompetent hosts. The present work was undertaken to evaluate the cytotoxic nature of fractionated antigens of A. fumigatus against the mammalian cell lines (J774, RAW, CHO and L929). An enriched protein antigenic fraction of A. fumigatus was subjected to con A Sepharose and phenyl Sepharose chromatography. Antigenic fractions, ConAub (conA unbound) and PSC III (fraction III of phenyl Sepharose column) containing low mw antigens showed higher cytotoxicity as compared to other antigenic fractions. PSC III was further purified on HPLC resulting in an 18 kDa homogeneous protein. The purified protein showed high ELISA absorbance values for specific IgG and IgE antibodies in sera of ABPA patients. Monoclonal antibody raised against Asp fl, a major allergen/antigen of A. fumigatus recognised the purified 18 kDa by ELISA and western blot. The 18 kDa allergen/antigen or Asp fl showed similar toxicity towards all the four cell lines (macrophage and fibroblast) with an IC50 of 75 ng/ml or 4.16 nM. Reduction in toxicity of 18 kDa at low temperatures and potentiation in presence of ammonium chloride and monensin indicates mechanism of internalisation of 18 kDa in eukaryotic cells is similar to alpha-sarcin. The present work shows that the 18 kDa allergen/antigen (Asp fl) is a major cytotoxin secreted by A. fumigatus which may play multiple roles in the pathogenesis of Aspergillosis through allergenicity, antigenicity and cytotoxicity.

Antioxidant therapy partially blocks immune-induced lung fibrosis.

A mouse model of hypersensitivity pneumonitis was generated by challenge with a thermophilic actinomycete. Oxygen radical scavengers were administered to challenged mice: vitamin E at 1000 units daily, polyethylene glycol-superoxide dismutase (SOD) at 500 units daily, polyethylene glycol-catalase at 10,000 units daily, 1,3,dimethyl-2-thiourea (DMTU) at 2 mg daily, and the biomimetic SOD, copper(II) [diisopropyl salicylate]2 (CuDIPS) at 1 mg daily. At three weeks after actinomycete challenge, a 10-fold increase in bronchoalveolar (BAL) cell number was observed. Treatments with catalase or DMTU were without effect on the BAL cell number in challenged mice. However, infusion of vitamin E was associated with an increased BAL cell influx (15-fold increase at two and three weeks). Similarly, treatment with PEG-SOD and CuDIPS resulted in an increase in cell number at two and three weeks. PEG-SOD or CuDIPS treatment resulted in a strong neutrophilia, whereas control challenged mice had a cellular influx mostly of macrophages and lymphocytes. Vitamin E treatment of challenged mice led to an increased T lymphocyte recruitment at two and three weeks. In vitro studies showed that actinomycete challenge was associated with an enhancement of alveolar macrophage O2- release, which was blocked by PEG-SOD, vitamin E, or DSC treatment but was unaffected by catalase or DMTU treatment. In control challenged mice, there was a 25-fold increase in the BAL albumin concentration at two weeks. PEG-SOD, vitamin E, or CuDIPS treatment all decreased the albumin concentration; the three modulators also diminished lung fibrosis at two or three weeks, as seen by a decrease in lung hydroxyproline and collagen synthesis by lung fibroblasts. Examination of sections from lungs of challenged animals showed evidence of cellular infiltrates around the bronchi and the blood vessels. Challenged mice given continuous infusions of vitamin E, SOD, or CuDIPS had lung histological scores that were significantly lower than control challenged mice or challenged mice treated with catalase or DMTU. Thus, therapies based on O2- scavenging or treatment with a general antioxidant such as vitamin E may hold some promise in the treatment of hypersensitivity pneumonitis.

Cyclosporin A increases the pulmonary eosinophilia induced by inhaled Aspergillus antigen in mice.

We evaluated the effects of anti-inflammatory drugs in a murine model of allergic bronchopulmonary aspergillosis (ABPA). Mice instilled with 100 micrograms of Aspergillus fumigatus antigen (intranasally, 3 days a week for 3 weeks) developed pulmonary lesions, characterized by a perivascular and peribronchial eosinophil infiltration, a bronchoalveolar lavage (BAL) eosinophilia, and elevated levels of total IgE, total IgG1 and A. fumigatus-specific IgG1. Under the same conditions, groups of mice receiving a daily dose of 2 mg/kg dexamethasone showed decreased numbers of eosinophils and total cells in BAL, had less numerous eosinophils in their pulmonary infiltrates, and had lower levels of serum and BAL fluid total IgE, total IgG1 and A. fumigatus-specific IgG1. Conversely, groups of mice pretreated with an immunosuppressive agent, cyclosporin A (CsA) at a dose of 50 mg/kg, three times per week, developed pulmonary lesions with enhanced lung eosinophilic influx and increased total IgE levels, both in serum and in BAL fluid. These findings show that dexamethasone potently prevents the murine immunopathologic response to A. fumigatus. The effect of CsA on this inflammatory response was paradoxical, insofar as it suggests an activation of the T helper 2 subset, which up-regulates eosinophil recruitment and IgE production.