Aspergillusfumigatus Recognition by Dendritic Cells Negatively Regulates Allergic Lung Inflammation through a TLR2/MyD88 Pathway.

Aspergillus fumigatus is an opportunistic fungal pathogen responsible for a spectrum of clinical manifestations. Dendritic cells recognize pathogen-associated molecular patterns of Aspergillus via two main receptor families, Toll-like receptors (TLRs) and C-type lectin receptors (CLR). Here, the importance of TLR and CLR signaling in the regulation of T-helper cell type 2 (Th2) responses was analyzed using a mouse model based on the transfer of bone marrow-derived dendritic cells (BMDCs) pulsed with A. fumigatus conidia. BMDCs were generated from mice deficient in either MyD88 or MALT1 (mucosa-associated lymphoid tissue lymphoma translocation protein 1). Both the MyD88 and MALT1 signaling pathway in BMDCs contributed to the production of inflammatory cytokines induced by A. fumigatus conidia. Mice sensitized with MyD88-/- BMDCs pulsed in vitro with A. fumigatus conidia showed an exacerbated allergic inflammation, with stronger eosinophil recruitment in the BAL and higher Th2 cytokine production compared with mice sensitized with wild-type or MALT1-/- BMDCs. This exacerbation was not observed when MyD88-/- BMDCs were pulsed with Cladosporium sphaerospermum, a nonpathogenic mold. A lack of TLR2 signaling recapitulated the exacerbation of the A. fumigatus Th2 response observed in the absence of MyD88 signaling, whereas TLR2 agonist dampened the response induced with A. fumigatus and C. sphaerospermum conidia. IL-10 production by BMDCs in response to A. fumigatus was dependent on the expression of TLR2 and MyD88. IL-10-/- BMDCs exacerbated, whereas MyD88-/- BMDCs supplemented with exogenous IL-10 decreased the allergic pulmonary inflammation. These results indicate that TLR2/MyD88-specific recognition of PAMPs from A. fumigatus conidia can upregulate IL-10 production and downregulate lung eosinophilia and the development of a Th2 response.

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.

Identification of genes required for Cf-dependent hypersensitive cell death by combined proteomic and RNA interfering analyses.

Identification of hypersensitive cell death (HCD) regulators is essential to dissect the molecular mechanisms underlying plant disease resistance. In this study, combined proteomic and RNA interfering (RNAi) analyses were employed to identify genes required for the HCD conferred by the tomato resistance gene Cf-4 and the Cladosporium fulvum avirulence gene Avr4. Forty-nine proteins differentially expressed in the tomato seedlings mounting and those not mounting Cf-4/Avr4-dependent HCD were identified through proteomic analysis. Among them were a variety of defence-related proteins including a cysteine protease, Pip1, an operative target of another C. fulvum effector, Avr2. Additionally, glutathione-mediated antioxidation is a major response to Cf-4/Avr4-dependent HCD. Functional analysis through tobacco rattle virus-induced gene silencing and transient RNAi assays of the chosen 16 differentially expressed proteins revealed that seven genes, which encode Pip1 homologue NbPip1, a SIPK type MAP kinase Nbf4, an asparagine synthetase NbAsn, a trypsin inhibitor LeMir-like protein NbMir, a small GTP-binding protein, a late embryogenesis-like protein, and an ASR4-like protein, were required for Cf-4/Avr4-dependent HCD. Furthermore, the former four genes were essential for Cf-9/Avr9-dependent HCD; NbPip1, NbAsn, and NbMir, but not Nbf4, affected a nonadaptive bacterial pathogen Xanthomonas oryzae pv. oryzae-induced HCD in Nicotiana benthamiana. These data demonstrate that Pip1 and LeMir may play a general role in HCD and plant immunity and that the application of combined proteomic and RNA interfering analyses is an efficient strategy to identify genes required for HCD, disease resistance, and probably other biological processes in plants.

Transaldolases are novel and immunoglobulin E cross-reacting fungal allergens.

BACKGROUND: Mould-induced atopic respiratory diseases are a worldwide problem. Characterization of fungal allergens is of major clinical importance. OBJECTIVE: We identified a novel transaldolase family allergen of Cladosporium and Penicillium species. METHODS: Fungal allergens were identified by immunoblotting, peptide mass mapping and partial sequencing, cDNA cloning and IgE epitope mapping. RESULTS: A 36.5 kDa IgE-binding component in a partially purified C. cladosporioides preparation was identified. Mass spectrometric analyses suggest that this novel IgE-reacting allergen is a transaldolase. A corresponding full-length 1246 bp cDNA encoding a polypeptide of 325 residues was isolated. The newly identified transaldolase allergen has been designated as Cla c 14.0101. The cDNA encoding the Pencillium chrysogenum transaldolase was isolated by RT-PCR according to the cDNA sequence encoding a P. chrysogenum Wisconsin 54-1255 hypothetical protein. The purified rCla c 14.0101 protein reacted with IgE antibodies in 10 (38%) of 26 Cladosporium cladosporioides-sensitized asthmatic patients. Nine of the 10 rCla c 14.0101-positive sera have IgE binding against the recombinant Penicillium transaldolase (rPen ch 35.0101). Among the eight fungal transaldolase-positive sera tested, three showed IgE binding against the recombinant human transaldolase. To determine cross-reactivity between the Cladosporium and Penicillium fungi, IgE cross-reactivity was detected between these two fungal transaldolase allergens by inhibition assays. Both the N- and the C-terminal fragments of Cla c 14.0101 were recognized by IgE antibodies. The C-terminal IgE-reacting determinant was narrowed down to a region encompassing Thr257 to Ser278 of Cla c 14.0101. It was mapped onto a loop-like structure of a 3D model constructed for Cla c 14.0101. CONCLUSION AND CLINICAL RELEVANCE: We identified transaldolase as a novel and IgE cross-reactive allergen family of C. cladosporioides and P. chrysogenum. In addition, an IgE-reacting fragment (Thr257 to Ser278) was pinpointed to a loop-like structure on Cla c 14.0101. Results obtained provide important information in clinical mould allergy.

Asthma severity according to Global Initiative for Asthma and its determinants: an international study.

BACKGROUND: The identification of the factors associated with severe asthma may shed some light on its etiology and on the mechanisms of its development. We aimed to describe asthma severity using the Global Initiative for Asthma (GINA) classification and to investigate its determinants in a cross-sectional, population-based sample in Europe. METHODS: In the European Community Respiratory Health Survey II (1999-2002), 1,241 adults with asthma were identified. Severity was assessed using the 2002 GINA classification (intermittent, mild persistent, moderate persistent, severe persistent) and it was related to potential determinants by a multinomial logistic model, using the intermittent group as the reference category for relative risk ratios. RESULTS: About 30% of asthmatic subjects were affected by moderate-to-severe asthma. Sensitization to Cladosporium was associated with a more than 5-fold greater risk of having (mild, moderate or severe) persistent asthma than intermittent asthma. Persistent asthma was positively associated with sensitization to house dust mite, nonseasonal asthma, an older age at asthma onset, and chronic cough and phlegm. Sensitization to cat increased the risk of severe asthma only. Smoking was more strongly associated with asthma severity in men, while rhinitis was more strongly associated with asthma severity in women. CONCLUSIONS: One third of the asthmatic population have moderate-to-severe asthma. Sensitization to perennial indoor allergens, particularly Cladosporium, is strongly associated with asthma severity. The role of smoking and rhinitis in determining asthma severity may differ between the sexes, and it should be further investigated.

Alternaria alternata TCTP, a novel cross-reactive ascomycete allergen.

Defining more comprehensively the allergen repertoire of the ascomycete Alternaria alternata is undoubtedly of immense medical significance since this mold represents one of the most important, worldwide occurring fungal species responsible for IgE-mediated hypersensitivity reactions ranging from rhinitis and ocular symptoms to severe involvement of the lower respiratory tract including asthma with its life-threatening complications. Performing a hybridization screening of an excised A. alternata cDNA library with a radioactively labeled Cladosporium herbarum TCTP probe, we were able to identify, clone and purify the respective A. alternata homologue of TCTP which again represents a multifunctional protein that has been evolutionarily conserved from unicellular eukaryotes like yeasts to humans and appears, summarizing current literature, to be involved in housekeeping processes such as cell growth as well as cell-cycle progression, the protection of cells against various stress conditions including for instance apoptosis, and in higher organisms even in the allergic response. In this context, our present study characterizes recombinant A. alternata TCTP as a novel minor allergen candidate that displays a prevalence of IgE reactivity of approximately 4% and interestingly shares common, cross-reactive IgE epitopes with its C. herbarum and human counterparts as determined via Western blotting and in vitro inhibition approaches.

Cladosporium species-related hypersensitivity pneumonitis in household environments.

Home-related chronic hypersensitivity pneumonitis (HP) is sometimes difficult to discriminate because patients do not have an obvious history of antigen exposure. We report two HP cases which developed in an office area and in a home: a 47-year-old woman with acute-onset HP and a 72-year-old woman with chronic HP followed up as idiopathic pulmonary fibrosis following isolation of Cladosporium cladosporioides and Cladosporium herbarum, respectively. Lymphocyte stimulating activity and antibody titer to these fungi were increased in these patients. Since Cladosporium spp. and several other fungi are present ubiquitously in our living environment, it is difficult to eliminate the antigen from the patients' environment to control the disease. Cladosporium spp. can be key antigens in inducing chronic HP in the home environment.

Cladosporium herbarum translationally controlled tumor protein (TCTP) is an IgE-binding antigen and is associated with disease severity.

Cladosporium herbarum represents one of the most important world-wide occurring allergenic fungal species. The prevalence of IgE reactivity to C. herbarum in patients suffering from allergy varies between 5 and 30% in the different climatic zones. Since mold allergy has often been associated with severe asthma, along with other allergic symptoms, it is important to define more comprehensively the allergen repertoire of this ascomycete. In this context we are reporting our successful approach to identify, clone, produce as a recombinant protein, purify and further characterize a new C. herbarum allergen which is a close homolog of the human translationally controlled tumor protein (TCTP, also called histamine releasing factor, HRF). The immunoreactivity of both pure recombinant molecules was investigated by means of immunoblot analyses, enzyme-linked immunosorbent assays as well as histamine release studies. To summarize, IgE antibodies from five out of nine individuals recognized both the human and the fungal protein in immunoblots. The latter was able to cause histamine release from human basophils with about half the efficiency compared to its human homolog HRF. Cross-inhibition assays showed that the patients' IgEs recognize common epitopes on both the human and C. herbarum proteins, but however, only pre-incubation with C. herbarum TCTP could completely inhibit reactivity with HRF. Furthermore, it appears that patients reactive to TCTP have a higher probability to suffer from asthma than other allergic patients.

Hypersensitivity pneumonia-nonspecific interstitial pneumonia/fibrosis histopathologic presentation: a study in diagnosis and long-term management.

BACKGROUND: Nonspecific interstitial pneumonia/fibrosis (NSIP) has been classified a form of idiopathic interstitial pneumonia/fibrosis. We have shown that cases of NSIP without demonstrable serum precipitins may be caused by inhalation of high levels of mold and/or bacteria in closed environments. OBJECTIVE: We report a patient with a clinical and histopathologic diagnosis of NSIP without serum precipitins caused by a microbial contamination in her home. Her case was converted from an acute to an insidious clinical presentation by inadequate remediation. A prolonged avoidance-challenge technique demonstrated that this case of NSIP was a form of hypersensitivity pneumonia that was reversible by effective remediation. METHODS: The patient was identified by compatible signs and symptoms, roentgenographic studies, pulmonary function tests, and a transbronchial lung biopsy. She was further evaluated with a detailed environmental history, serologic tests, and investigation of the home environment. An environmental avoidance and challenge technique was performed to confirm cause and effect and to determine that remediation had been effective. RESULTS: Review of the biopsy showed NSIP and failed to reveal any non-caseating granuloma formation. Investigation of the home revealed a Cladosporium species contamination of the air conditioning system and Penicillium species beneath an entryway carpet. Serum precipitins to commercial antigens of common mold to the south Texas area were negative. Avoidance and challenge techniques confirmed the home as the causative environment in this case of NSIP. The patient has been free of signs and symptoms and has taken no medication for interstitial lung disease over the past 30 months. CONCLUSIONS: Some cases of NSIP may be caused by inhalation of microbial antigen(s) in a closed environment. An environmental challenge technique was an effective method to determine the causative environment and confirm that remediation had been effective. Inadequate remediation may lead to symptomatic improvement, but may convert a patient from an acute to an insidious presenter. The environmental challenge obviates a need for specific challenges to determine specific causation. Remediation of or moving from an environmental contamination to achieve reversibility or prevent progression was the treatment of choice to avoid use of long-term immunosuppressive agents.

Housing characteristics, reported mold exposure, and asthma in the European Community Respiratory Health Survey.

BACKGROUND: The effects of home dampness and mold exposure on adult asthma are not clear. OBJECTIVE: We aimed to investigate the associations between housing characteristics related to dampness, mold exposure, and house dust mite levels and adult asthma in 38 study centers from the European Community Respiratory Health Survey. METHODS: Data about the present home, heating and ventilation systems, double glazing, floor covers, recent water damage, and mold exposure were obtained by means of an interviewer-led questionnaire. The associations between these factors and asthma, as defined on the basis of symptoms in the last year, and of bronchial responsiveness, as determined with methacholine challenge, were evaluated. Odds ratios (ORs) were obtained by using random-effects meta-analyses adjusted within study centers for sex, age group, and smoking status. RESULTS: Fitted carpets and rugs in the bedroom were related to fewer asthma symptoms and bronchial responsiveness (OR range, 0.69-0.91). This effect was consistent across centers and more pronounced among house dust mite-sensitized individuals. Reported mold exposure in the last year was associated with asthma symptoms and bronchial responsiveness (OR range, 1.14-1.44). This effect was homogeneous among centers and stronger in subjects sensitized to Cladosporium species. In centers with a higher prevalence of asthma, the prevalence of reported indoor mold exposure was also high. This association was observed for reported mold exposure by asthmatic subjects (Spearman r (s) = 0.46), as well as reported mold exposure by nonasthmatic subjects (r (s) = 0.54). Reported mold exposure was highest in older houses with recent water damage. CONCLUSION: We conclude that indoor mold growth has an adverse effect on adult asthma.

IgE-binding epitopes of enolases, a class of highly conserved fungal allergens.

BACKGROUND: Cladosporium herbarum and Alternaria alternata are two of the most prominent fungal species inducing type I allergy. Previously, we have demonstrated that enolase (Cla h 6) is the second most important allergen of C herbarum in terms of frequency of sensitization. OBJECTIVE: IgE-reactive B-cell epitopes of C herbarum enolase were analyzed, and cross-reactivity between fungal enolases was investigated. METHODS: Cla h 6 glutathione-S-transferase fusion peptides were constructed by means of PCR cloning. A alternata enolase (Alt a 5) was isolated by screening a complementary (c)DNA expression library with a C herbarum enolase DNA probe. RESULTS: Mapping of Cla h 6 IgE-binding epitopes identified a peptide with a length of 69 amino acids (peptide 9), which bound IgE from 8 of 8 patients. Analysis of the conformation of peptide 9 revealed that it does not form a compact structure but rather spans the whole length of the protein, with side chains exposed to solvent at 3 locations. Peptide 9 in the context of Escherichia coli glutathione-S-transferase not only binds IgE but also competitively inhibits IgE binding to Alt a 5. This result indicates that the epitope or epitopes on peptide 9 constitute a major cross-reacting epitope or epitopes on the enolases from C herbarum and A alternata in the case of the one patient tested. CONCLUSIONS: We demonstrated that the glycolytic enzyme enolase is an allergen not only in C herbarum but also in A alternata. Additionally, enolase was shown to exhibit high cross-reactivity to other fungal enolases. On the basis of the results presented here, we propose the use of recombinant Cla h 6 or maybe even peptide 9 of Cla h 6 for diagnosis and possibly therapy of mold allergy.

Protease-dependent activation of epithelial cells by fungal allergens leads to morphologic changes and cytokine production.

BACKGROUND: Proteases in extracts of Aspergillus fumigatus cause epithelial cell desquamation and release of proinflammatory cytokines. OBJECTIVE: We sought to assess protease activity in Alternaria alternata, Cladosporium herbarum, and Aspergillus fumigatus extracts and study the ability of these extracts to cause desquamation and release of proinflammatory cytokines from epithelial cells. METHODS: Protease activities of the fungal extracts were quantified. Changes with respect to cell morphology, cell desquamation, and cytokine production (IL-6 and IL-8) were measured in the absence and presence of the fungal extracts in an airway-derived epithelial cell line (A549) and primary epithelial nasal cells. RESULTS: Fungal proteases differentially induced morphologic changes, cell desquamation, and production of IL-6 and IL-8 in a dose- and time-dependent fashion. Alternaria alternata extracts induced cell shrinking and cell desquamation and strongly enhanced the production of IL-6 and IL-8 at higher concentrations. Aspergillus fumigatus extracts caused cell shrinking, cell desquamation, and production of IL-6 and IL-8, even at low concentrations. The Aspergillus fumigatus-derived extract grown on collagen medium induced a strong dose-dependent decline in cytokine production at higher concentrations. Cladosporium herbarum extracts did not induce morphologic changes or cell desquamation but enhanced IL-6 and IL-8 productions at higher concentrations. The dependence of these effects on intact protease activity was shown by their abrogation by protease inhibitors. CONCLUSION: Proteases present in fungal extracts interact with epithelial cells, leading to morphologic changes, cell desquamation, and induction of proinflammatory cytokines. It is proposed that these fungal proteases may activate epithelial cells through a protease-activated receptor type 2-driven mechanism.

The association of smoking with sensitization to common environmental allergens: results from the European Community Respiratory Health Survey.

BACKGROUND: Smoking is a risk factor for sensitization to some occupational allergens, but its association with sensitization to common environmental allergens remains unclear. OBJECTIVE: We sought to determine the association of smoking with total IgE levels and with sensitization to 3 common environmental allergens in data from the European Community Respiratory Health Survey. METHODS: A detailed smoking history and blood sample for determination of serum total IgE and specific IgE levels to house dust mite, grass, and cat allergens was obtained from 13,002 randomly selected young adults living in the areas served by 34 centers in 14 countries. Associations with smoking status and amount smoked were determined. Because there was evidence of heterogeneity between centers in the association of age, sex, and smoking with sensitization, odds ratios (ORs) were determined for each center and combined by using random-effects meta-analysis. RESULTS: Compared with lifetime nonsmokers, current smokers were at an increased risk of sensitization to house dust mite allergen (OR, 1.13; 95% confidence interval [CI], 1.02-1.26) but a decreased risk of sensitization to grass (OR, 0.76; 95% CI, 0.67-0.88) and cat allergens (OR, 0.69; 95% CI, 0.59-0.80). Exclusion of those with symptoms suggestive of current asthma strengthened the association of smoking with sensitization to house dust mite allergen (OR, 1.29; 95% CI, 1.11-1. 50). The geometric mean total IgE level was higher in smokers and was higher among those who currently smoked the most compared with those who smoked less than 5 cigarettes per day. CONCLUSION: The association between smoking and sensitization to common environmental allergens is different for different allergens.

Sensitization to individual allergens and bronchial responsiveness in the ECRHS. European Community Respiratory Health Survey.

Little is known about the relation of bronchial responsiveness (BHR) to sensitization to individual allergens, or its variation between countries. Data were obtained for BHR, specific immunoglobulin E and confounding variables from 11,215 subjects, aged 20-44 yrs at the start of the European Community Respiratory Health Survey, in 34 centres in 15 countries. The relation of BHR to sensitization to cat, house dust mite, timothy grass and Cladosporium was estimated by means of multiple regression for each centre, and combined across centres by random effects meta-analysis, controlling for baseline lung function, height, sex, season of testing, age, smoking and age/sex and age/smoking interactions. BHR was greater, on average, in those sensitized to cat (p=0.023), house dust mite (p<0.001) and timothy grass (p=0.018), but not to Cladosporium (p=0.60), and increased with degree of sensitization (p<0.001). All relations showed heterogeneity between centres, although to a lesser extent in the relation to sensitization to house dust mite. More variation in bronchial responsiveness was explained by sensitization and degree of sensitization to the individual allergens than by atopy defined as any positive test in each centre, but the relative importance of each allergen varied. The use of atopy as a single variable in relation to bronchial hyperresponsiveness may be misleading.

Childhood environment and adult atopy: results from the European Community Respiratory Health Survey.

BACKGROUND: Previous literature has indicated that environmental exposures in childhood influence development of atopic sensitization. OBJECTIVE: We sought to study the association between childhood environment and adult atopy. METHODS: Thirteen thousand nine hundred thirty-two subjects aged 20 to 44 years from 36 areas in Europe, New Zealand, the United States, and Australia took part in the European Community Respiratory Health Survey, answering interviewer-led questionnaires and providing blood tests for measurement of specific IgE to grass, house dust mite, cat, and Cladosporium allergens. RESULTS: Atopy was negatively associated with family size (OR = 0. 93; 95% CI = 0.90-0.96 per 1 sib), partly attributable to an independent protective effect of a greater number of brothers (OR = 0.92; 95% CI = 0.89-0.95 per 1 brother). Accounting for total number of siblings, no further influence was detected for number of older or younger siblings. Bedroom sharing was associated with a lower prevalence of atopy, particularly to cat allergen. A protective effect of family size and bedroom sharing could only be detected in subjects reporting no parental allergy (family size, test for interaction P =.012). The presence of a dog in the home in childhood was negatively associated with adult atopy (OR = 0.85, 95% CI = 0. 78-0.92), an effect that remained after adjustment for parental allergy, sibling allergy, and adult pet ownership. CONCLUSION: Subjects from large families with brothers, shared bedrooms, and dogs in childhood were less often atopic as adults. Our findings are consistent with the hypothesis that infectious agents could inhibit development of atopy during childhood. However, in subjects with a strong genetic predisposition, environmental factors in childhood are possibly of less importance.

Individual allergens as risk factors for bronchial responsiveness in young adults.

BACKGROUND: Bronchial responsiveness is known to be related to atopy, but the relative contribution of sensitisation to individual allergens in the UK, or whether serum total IgE is an independent risk factor, is unknown. METHODS: A random sample of 1864 men and women aged 20-44 years, drawn from family health service registers in Cambridge, Ipswich and Norwich, was invited to answer a detailed questionnaire, undergo skin prick tests and methacholine bronchial challenge, and provide a serum sample for measurement of total and specific IgE. The relation of bronchial responsiveness to risk factors was studied in 749 subjects (40.2%) with complete data. RESULTS: Bronchial responsiveness was increased in those sensitised to cat, D pteronyssinus, Timothy grass and Cladosporium, but decreased in subjects also positive to birch allergen. Additional skin prick tests added little information. Serum total IgE was not significantly related after adjustment for specific IgE to the five allergens. Increasing titres of specific IgE to D pteronyssinus were associated with increasing bronchial responsiveness. Specific IgE to Cladosporium had a prevalence of around 3%, but was associated with greatly increased responsiveness. Decreased baseline lung function was related (p < 0.001) to increased responsiveness. There was an interaction between age and smoking status, with lower responsiveness in older non-smokers. CONCLUSION: Atopy is the most important risk factor for bronchial responsiveness in this age group, but effects are not additive across all allergens. Research in reducing exposure to house dust mite should also address the role of Cladosporium sensitisation and exposure to indoor moulds.

Distribution of total serum IgE and specific IgE to common aeroallergens by sex and age, and their relationship to each other in a random sample of the Dutch general population aged 20-70 years. Dutch ECRHS Group, European Community Respiratory Health Study.

To describe the distribution of serum total IgE and specific IgE to common aeroallergens by sex and age and to study their relationship to each other, we measured serum total IgE and specific IgE (CAP) to house-dust mite, timothy grass, cat, birch, and Cladosporium in a random sample of 2496 subjects, aged 20-70 years from the Dutch general population. We found that total IgE was higher in men, independently of smoking, and that total IgE had no relationship with age after adjustment for specific IgE and smoking in linear regression analysis. At least one positive specific IgE test was found in 32% in both sexes. Men had higher prevalences of specific IgE to house-dust mite and lower prevalences of specific IgE to birch than women. The proportion with positive specific IgE decreased with age. The mean total IgE increased with the number of positive specific IgE tests. Thus, total IgE is higher in men and has no relationship with age if specific IgE is taken into account. The prevalences of specific IgE to aeroallergens are high and decrease with increasing age. We suggest that sex differences in total IgE should be considered when using total IgE.

Sensitization to Alternaria and Cladosporium by the age of 4 years.

Of 1218 children born on the Isle of Wight in 1989/90, and followed for atopy at age 4 years, 981 were skin-prick tested with a battery of allergens. Of these 61 (6%) reacted positively to Alternaria alternata and Cladosporium herbarum (47 to Alternaria, 21 to Cladosporium and seven to both). Twenty-four (39%) were asymptomatic (latent atopy) of which 12 had a single positive reaction either to Alternaria or Cladosporium. Asthma was the most common disease in children sensitized to moulds. Alternaria sensitization correlated positively with clinical diagnosis of asthma (P < 0.01), eczema (P < 0.001) and rhinitis (P < 0.05). Likewise, Cladosporium sensitivity correlated with a diagnoses of asthma, eczema and rhinitis (all P < 0.05). Age of the house correlated with reported damp and lack of central heating (both P < 0.001), but not with sensitization to moulds. An association between the presence of damp or age of the house and mould allergy was confounded by 21 children moving house in the first 4 years. Exposure to pets, passive tobacco smoking and season of birth had no bearing on mould sensitivity. At 4 years of age Alternaria and Cladosporium were the third most common causes of sensitization, i.e. after house dust mite and grass pollen.

An allergenic polypeptide representing a variable region of hsp 70 cloned from a cDNA library of Cladosporium herbarum.

BACKGROUND: Extracts of Cladosporium herbarum, a major source of fungal aeroallergens, exhibit a complex profile of IgE-binding proteins. Yields of conventionally purified allergens from this mold have been insufficient to permit further molecular analyses. OBJECTIVE: To enhance and simplify the purification of allergens from C. herbarum, we have sought to use recombinant DNA techniques to clone, identify and bacterially express immunoselected C. herbarum allergens. METHODS: We constructed a cDNA library in lambda ZAP II using mRNA isolated from C. herbarum. From this library, phage clones encoding a new allergen were immunoselected using pooled human atopic IgE. The cloned cDNA was excised from the phage vector as a recombinant pBluescript II SK-phagemid and sequenced. Expression of the recombinant allergen was carried out in E. coli XL1-blue transformants of the phagemid. Bacterial lysates from cells induced to express the cloned allergen were immunoblotted and probed with individual human atopic IgEs. RESULTS: The cDNA clone encodes a 278 amino acid polypeptide homologous to the C-terminal portion of 70 kDa heat shock protein (hsp 70). The polypeptide possesses features common to other hsps 70, i.e. a similar hydropathic profile and a variable C-terminal region with conserved sequence at the very C-terminus. Binding of the recombinant peptide to IgE from 38% of atopic sera or plasma from individuals allergic to C. herbarum was demonstrated. CONCLUSION: These results indicate that amino acid substitutions are relatively conserved even in the variable C-terminal regions of hsp 70 species. Thus, this study should draw attention to the possibility of induction of anaphylactic responses in a sensitized individual when hsp 70 from any pathogenic species is administered for vaccination.

Variación anual de la microflora en la ciudad de San Juan y en hogares de pacientes con patología respiratoria IgE dependiente / Annual mycoareological variation in San Juan city, Argentine Republic, and in houses of IgE dependent respiratory pathology patients

El objetivo del estudio fue establecer la variación anual de la microflora en la ciudad de San Juan y en hogares de pacientes con patología respiratoria IgE dependiente. San Juan es una provincia del oeste de la República Argentina, con escasísimas precipitaciones pluviales anuales (menos de 10 mm), con un promedio de humedad relativa ambiente de 46 por ciento (min.: 36 por ciento y máx.: 55 por ciento) y una temperatura promedio de 17,6ºC (min.: 7,8ºC y máx.: 26,5ºC). Para poder conocer el desarrollo de hongos y definir mejor la correlación existente entre ellos y las enfermedades alérgicas respiratorias, estudiamos durante un período anual (julio 1994-junio 1995) la presencia de seis géneros de hongos: Alternaria, Cladosporium, Penicillium, Aspergillus, Mucor y Rhizopus, en el ambiente exterior de la ciudad de San Juan, y en el domicilio de nueve (9) niños con enfermedad respiratoria (rinitis y/o asma), con Prick Test positivo para todos los hongos en estudio. Se controló la reactividad sanguínea de estos pacientes a los mismos géneros de hongos por IgE RAST. La flora micológica fue estudiada por el método gravimétrico, exponiendo mensualmente cápsulas de Petri (diámetro: 10 cm) en medio ambiente externo y en los domicilios (4 cápsulas por domicilio), con medios de cultivo de Sabouraud y Czapek-Dox (Lab. Merck). Los Prick Test se realizaron con antígenos Allergon AB (Lab. Welt), y las IgE RAST (Allerex Labs. Inc - USA). El hongo que se desarrolló con más frecuencia en los domicilios estudiados fue el Penicillium (40,63 por ciento), seguido por Rhizopus (17,24 por ciento), Aspergillus (14,09 por ciento), Mucor (11,28 por ciento), Cladosporium (4,81 por ciento), Alternaria (4,75 por ciento), y otros (7,0 por ciento). Aunque en distinto porcentaje, la distribución de hongos en ambientes externos sigue una curva muy similar a las halladas en los domicilios: Penicillium (17,86 por ciento), Rhizopus (12,76 por ciento), Aspergillus (11,13 por ciento), Mucor (9,97 por ciento), Alternaria (8,12 por ciento), Cladosporium (6,03 por ciento) y otros (1,39 por ciento). La mayor concentración de hongos se alcanzó en octubre para domicilios y en noviembre-diciembre para ambiente exterior. La mejor correlación entre el Prick Test y el RAST se obtuvo para Alternaria y Aspergillus (87 por ciento), seguidos por Cladosporium (75 por ciento), Penicillium (62 por ciento), Rhizopus (50 por ciento), y Mucor (37 por ciento). No encontramos correlación directa entre la respuestas de los pacientes y la concentración de hongos en el período de estudio, confirmando lo esperado de acuerdo con las diferentes potencias alergénicas de cada género