Allergic Bronchopulmonary Aspergillosis Patients Research Articles

HLA-DR, IL-4RA, and IL-10: Genetic Risk Factors in Allergic Bronchopulmonary Aspergillosis

Background: Allergic bronchopulmonary aspergillosis (ABPA) is a bronchial allergic inflammatory reaction to Aspergillus fumigatus that occurs in a minority of susceptible asthmatic and cystic fibrosis (CF) patients. Previous studies identified that HLA-DR2/DR5 was associated with susceptibility to develop ABPA; however, HLA-DR2/DR5 occurs frequently in non-ABPA patients as well. Objective: We hypothesize that in addition to HLA-DR restriction, other genetic risk factors predispose asthmatic and CF patients to develop ABPA. Methods: HLA-DR and interleukin-4 (IL-4) receptor α-chain (IL-4RA), IL-13, and IL-10 -1082 polymorphisms were examined in 41 asthmatic and CF patients with ABPA and in 84 asthmatic and CF non-ABPA patients. Results: HLA-DR2 and/or DR5 were identified in 70.7% of ABPA patients and in 35.7% of non-ABPA patients. IL-4RA single-nucleotide polymorphisms (SNPs) were present in 95% of ABPA patients, with the ile75val SNP in 80.5% of ABPA patients. Both HLA-DR2/DR5 and IL-4RA SNPs individually were associated with increased risk for the development of ABPA; however, the combination of HLA-DR2/DR5 and ile75val predicted the greatest risk with an odds ratio (OR) of 6.6. There was a trend for increased frequency of the IL-10 -1082 GG genotype in ABPA patients, and the combination of HLA-DR2/DR5, ile75val and IL-10 -1082 G genotype was associated with increased risk in the development of ABPA, OR 8.0. The IL-13 arg110gln SNP was not increased in ABPA patients. Conclusions: Genetic risks for the development of ABPA include HLA-DR2/DR5 and IL-4RA ile75val and IL-10 -1082G polymorphisms.

Auto‐ and cross‐reactivity to thioredoxin allergens in allergic bronchopulmonary aspergillosis

Thioredoxins are cross-reactive allergens involved in the pathogenesis of atopic eczema and asthma. Cross-reactivity to human thioredoxin can contribute to the exacerbation of severe atopic diseases. Human thioredoxin, Asp f28 and Asp f29, two thioredoxins of Aspergillus fumigatus, and thioredoxin of Malassezia sympodialis were cloned and produced as recombinant proteins. Allergenicity and cross-reactivity to thioredoxins in allergic bronchopulmonary aspergillosis patients were assessed by enzyme-linked immunosorbent assay (ELISA), inhibition ELISA, immunoblot analysis, proliferation assays and skin tests. Molecular homology modelling was used to identify conserved, surface-exposed amino acids potentially involved in immunoglobulin E (IgE)-binding. All thioredoxins, including the human enzyme, bind IgE from patients with allergic bronchopulmonary aspergillosis and induce allergen-specific proliferation in peripheral blood mononuclear cells and positive skin reactions in thioredoxin-sensitized patients. Inhibition experiments showed that the thioredoxins are cross-reactive indicating humoral immune responses based on molecular mimicry. To identify structural surface elements involved in cross-reactivity, the three-dimensional structures were modelled based on solved thioredoxin structures. Analysis of the molecular surfaces combined with sequence alignments allowed identification of conserved solvent exposed amino acids distantly located in the linear sequences which cluster to patches of continuous surface areas. The size of the surface areas conserved between human and fungal thioredoxins correlates well with the inhibitory potential of the molecules in inhibition ELISA indicating that the shared amino acids are involved in IgE-binding. Conserved, solvent exposed residues shared between different thioredoxins cluster to continuous surface regions potentially forming cross-reactive conformational B-cell epitopes responsible for IgE-mediated cross-reactivity and autoreactivity.

Serologic diagnosis of allergic bronchopulmonary aspergillosis in patients with cystic fibrosis through the detection of immunoglobulin G to Aspergillus fumigatus

Allergic bronchopulmonary aspergillosis (ABPA) is seen in approximately 10% of patients with cystic fibrosis (CF) and can be difficult to diagnose. Consensus criteria require the presence of multiple elevated immunologic markers such as total immunoglobulin E (IgE), Aspergillus IgE and Aspergillus IgG, or precipitins for a robust diagnosis. There is some degree of standardization of total IgE and Aspergillus IgE levels, but there is no standardization in the measurement of IgG antibodies or precipitins to Aspergillus. The interpretation of results may, therefore, be confusing. Eighty-seven patients with CF were categorized as having ABPA or as controls, using the consensus criteria and an in-house enzyme immunoassay to measure IgG levels to Aspergillus. All sera from patients were then analyzed by commercial fluorescent immunoassay (FEIA) for the quantitative detection of anti- Aspergillus IgG. FEIA results were analyzed against the consensus conference minimum diagnostic criteria to ascertain a cutoff point, which could predict a diagnosis of ABPA in CF. Eighty patients with CF and with no or incomplete evidence of ABPA had a mean FEIA score of 51.1 mg/L, whereas 7 CF patients with ABPA had a mean FEIA score of 132.5 mg/L. Using receiver operator characteristic curve analysis of the ImmunoCAP (Phadia) IgG score on ABPA versus all other patients gave an area under the curve of 0.933 (estimated SE, 0.027). This analysis provisionally suggested that a score of 90 mg/L may be used as a cutoff point, which would give a sensitivity of 91% and specificity of 88.0% for the diagnosis of ABPA, though this requires further validation. This quantitative approach to Aspergillus IgG measurement in patients with CF along with the results of other tests will hopefully provide a more accurate approach to the diagnosis of ABPA.

A Study on Prevalence of Allergic Bronchopulmonary Aspergillosis in Patients of Bronchial Asthma

Objective: To determine the prevalence of allergic bronchopulmonary aspergillosis (ABPA) in patients of bronchial asthma. Methods: Two hundred and forty four patients of bronchial asthma, recruited consecutively over a period of three years were analyzed prospectively by clinical evaluation, chest radiography, skin test, sputum culture for fungus and serum precipitin test. Those patients with suspicion of ABPA were further investigated by serum titers of specific IgG and IgE against A. fumigatus. Diagnosis of ABPA was made on pre determined major and minor criteria, where at least five major criteria had to be present. Results: During the study period, 244 patients (150 males; 94 females) with bronchial asthma diagnosed on basis of clinical features and spirometric findings were recruited in the study, with mean age of 27.1 years (9 to 60 years). Mean duration of illness of these patients was 11.2 years (1.5 to 32 years). Immediate cutaneous reactivity to A. fumigatus (Type I) revealed hypersensitivity to the fungus in 30.3% of the patients. On basis of clinical, radiological and immunological criteria, 18 (7.4%) patients (13 males and 5 females) were diagnosed to have ABPA. Their mean age was 33.5 years (17 to 48 years) and mean duration of illness was 11.8 years (1.5 to 28 years). Family history suggestive of atopy was present in 61.5% and history of passage of mucus plugs was present in 66.6% patients. All these patients with ABPA were misdiagnosed as cases of pulmonary tuberculosis, and were given anti tuberculosis treatment. Conclusion: Allergic bronchopulmonary aspergillosis is seen in 7.4% patients with bronchial asthma. Efforts should be made to improve the awareness level about this disease, among general physicians who frequently confuse it with pulmonary tuberculosis, for timely diagnosis and institution of appropriate treatment so as to avoid misuse of antitubercular drugs and prevention of end stage irreversible lung damage.

Potential of Lung Surfactant Proteins, SP-A and SP-D, and Mannan Binding Lectin for Therapy and Genetic Predisposition to Allergic and Invasive Aspergillosis

A significant proportion of bronchial asthma patients have underlying pulmonary fungal infections that contribute to persistent inflammation and allergic reactions. Aspergillus fumigatus is a ubiquitous opportunistic fungal pathogen causing a spectrum of allergic and infectious diseases. Currently, oral corticosteroids form the first line of treatment for allergic aspergillosis and use of antifungals such as itraconazole has been indicated in non-responders. In view of the protective role of innate immunity in host defense against Aspergillus fumigatus, we aimed to identify the relevant innate immune proteins In a series of studies, we identified and established the therapeutic potential of pulmonary collectins SP-A and SP-D and serum collectin MBL in murine models of allergic and invasive aspergillosis. Use of SP-D for diagnosis and therapy of lung disorders and MBL for therapy of various infections including invasive aspergillosis has been patented. Genetic polymorphisms in these genes may result in partial or total loss of function and may increase the host's susceptibility to aspergillosis. Candidate gene association studies showed SNPs in SP-A2 and MBL significantly associate with patients of allergic bronchopulmonary aspergillosis and bronchial asthma with rhinitis. The patients carrying either one or both of GCT and AGG alleles of SP-A2 and patients with A allele at position 1011 of MBL had markedly higher eosinophilia, total IgE antibodies and lower FEV1 (the clinical markers of ABPA). These SNPs may be useful for predicting susceptibility to allergic aspergillosis and bronchial asthma with allergic rhinitis and have been patented. Elucidation of the immunoregulatory role of SP-A, SP-D and MBL in mechanisms of allergy and inflammation suggests that they may also be potentially useful for predisposition diagnosis and therapy of non-fungal bronchial asthma.

Comparison of serum markers for allergic bronchopulmonary aspergillosis in cystic fibrosis

The diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in cystic fibrosis (CF) is a challenge. Thymus- and activation-regulated chemokine (TARC) has recently been reported to play a role in ABPA. The aim of this study was to compare the diagnostic value of TARC with that of known serological markers for diagnosis of ABPA in CF patients. The present study longitudinally followed 48 CF patients, of whom 12 had a diagnosis of ABPA according to Nelson's criteria, for 1-8 yrs with repeated measurements of serum total immunoglobulin (Ig)E, specific Aspergillus fumigatus IgE and IgG, specific IgE against recombinant A. fumigatus allergens (rAsp f) 1, 3, 4 and 6, and TARC. Median (interquartile range) TARC levels were 589 (465-673) pg x mL(-1) in ABPA patients and 232 (189-289) pg x mL(-1) in non-ABPA patients. Receiver operating characteristic curves revealed that TARC was superior to the other markers for diagnosis of ABPA. Diagnostic accuracy was greater for TARC (93%) than for total IgE (74%), or rAsp f 4 (75%) or f 6 (79%). The present study indicates that thymus- and activation-regulated chemokine may be useful in the diagnosis of allergic bronchopulmonary aspergillosis in cystic fibrosis patients. However, larger studies are needed before thymus- and activation-regulated chemokine can routinely be used in diagnostic algorithms.

Role of chest radiography in the diagnosis of allergic bronchopulmonary aspergillosis in adult patients with cystic fibrosis

This study aimed to verify the usefulness of chest radiography in the diagnosis of allergic bronchopulmonary aspergillosis (ABPA) in adult patients with cystic fibrosis. Eleven patients (with a total of 14 episodes) affected by ABPA were selected from among subjects attending a Regional Cystic Fibrosis Centre. For each episode, we retrospectively reviewed the baseline chest radiographs obtained before the diagnosis of ABPA, those obtained during the course of ABPA and those obtained during follow-up. Radiographs were assessed for the presence of bronchial wall thickening, bronchiectasis, infiltrates, atelectasis, mucoid impaction, lymphadenopathy, pleural effusion and fluid levels. Radiographic findings that had appeared at the time of ABPA diagnosis and disappeared after treatment were considered related to ABPA and thus useful for a correct diagnosis of the disease. Chest radiograph abnormalities were compared with changes on the respiratory function tests [forced expiratory volume in 1 s (FEV1)] during the different stages of the disease. Radiographic findings at the time of ABPA diagnosis appeared to have deteriorated in 8/14 cases when compared with the baseline films; after treatment, the radiographic findings deteriorated in 6/14 cases and improved in 6/14. The most significant among the radiographic signs considered (infiltrates and mucoid impaction) appeared at the time of ABPA diagnosis in 7/14 and 4/14 cases, respectively, and in some patients, they were also present at baseline and persisted during follow-up. FEV1 values were significantly decreased (>10%) in 9/14 cases at the time of ABPA diagnosis. Our results demonstrate the limited usefulness of chest radiography in the diagnosis of ABPA in patients with cystic fibrosis. The most significant abnormalities are nonspecific and commonly seen on baseline films in cystic fibrosis without ABPA and persist after treatment in most cases.

Análisis farmacoeconómico de la pentoxifilina en úlceras venosas

The etiology of allergic bronchopulmonary aspergillosis (ABPA) is not well understood. A clinical phenotype resembling the pulmonary disease seen in cystic fibrosis (CF) patients can occur in some individuals with ABPA. Reports of familial occurrence of ABPA and increased incidence in CF patients suggest a possible genetic basis for the disease. To test this possibility, the entire coding region of the cystic fibrosis transmembrane regulator (CFTR) gene was analyzed in 11 individuals who met strict criteria for the diagnosis of ABPA and had normal sweat electrolytes (< or = 40 mmol/liter). One patient carried two CF mutations (deltaF508/R347H), and five were found to carry one CF mutation (four deltaF508; one R117H). The frequency of the deltaF508 mutation in patients with ABPA was significantly higher than in 53 Caucasian patients with chronic bronchitis (P < .0003) and the general population (P < .003). These results suggest that CFTR plays an etiologic role in a subset of ABPA patients.

Chemokines in Allergic Aspergillosis - From Animal Models to Human Lung Diseases

Allergic bronchopulmonary aspergillosis (ABPA) is a frequent syndrome in patients with cystic fibrosis (CF) or asthma. Animal models revealed distinct roles for the chemokines CCL2, CCL3, CCL5, CCL6, CCL17 and CCL22 and their receptors in the pathogenesis of allergic aspergillosis. In humans, serum levels of the CCR4 ligand CCL17 identified ABPA in patients with CF or asthma, suggesting CCL17 as novel diagnostic marker and future therapeutical target in ABPA. This review illustrates the manifold role of chemokines in animal models of allergic aspergillosis and translates these findings to human lung diseases.

Chemokine receptor expression on allergen‐specific T cells in asthma and allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is a rare variant of severe asthma resulting from hypersensitivity to Aspergillus fumigatus (Asp f) present in the airways. We analyzed the expression of a panel of six chemokine receptors (CCR3, CCR4, CCR8, CCR5, CXCR3 and CXCR4) on total blood CD4(+) T cells and Asp f-specific-T cells in ABPA patients. We hypothesized that chemokine receptor pattern on T cells differs between ABPA patients, non-ABPA allergic asthmatics sensitized to Dermatophagoides pteronyssinus (Der p) or Phleum pratense (Phl p) and healthy controls. We used the fluorescent dye PKH26, a membrane bound marker, to identify accumulated proliferating (cell-sorted PKH26(low)) CD4(+) T cells in response to allergens (Asp f, Der p, Phl p) or recall antigens (PPD and TT). Chemokine receptor expression was analyzed by flow cytometry on proliferating CD3(+) CD4(+) PKH26(low) cells. Stimulation of CD4(+) T cells with the relevant allergen resulted in different patterns of chemokine receptor expression in ABPA and non-ABPA allergic asthmatics. Upon Asp f exposure, proliferating CD4(+) T cells from ABPA patients down-regulated the expression of CCR4 and CXCR3 while CCR4 and CXCR3 were up-regulated in allergen-specific T cells from non-ABPA allergic asthmatics. Considering each group of patients, the pattern of chemokine receptors expressed on proliferating allergen-specific CD4(+) T cells was similar to that expressed by recall antigen-specific T cells. The down-regulation of CCR4 and CXCR3 after allergen exposure in Asp f-specific T cells seems to be a characteristic feature of ABPA patients and requires further evaluation.

Chemokines Indicate Allergic Bronchopulmonary Aspergillosis in Patients with Cystic Fibrosis

Allergic bronchopulmonary aspergillosis (ABPA) is characterized by a Th2 immune response. Mouse models suggest a critical role for the Th2 chemokines thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) in ABPA. To determine whether serum levels of TARC and MDC characterize ABPA in patients with cystic fibrosis (CF) and to examine longitudinally if levels of TARC and MDC indicate ABPA exacerbations in patients with CF. Levels of TARC and MDC and levels of Th1 (IL-12 and IFN-gamma) and Th2 (IL-4, IL-5, and IL-13) cytokines were analyzed in serum of 16 patients with CF with ABPA, six non-CF patients with asthma with ABPA, 13 patients with CF colonized with Aspergillus fumigatus, six patients with CF sensitized to A. fumigatus, 12 atopic patients with CF, and 13 non-CF atopic control subjects by ELISA. The longitudinal course of TARC, MDC, and IgE levels was assessed during ABPA episodes. Patients with ABPA had significantly higher serum levels of TARC compared with the other patient groups. Cytokine levels did not differ among the patient groups. Longitudinally, levels of TARC indicated ABPA exacerbations in patients with CF more clearly than IgE levels. In patients with CF and ABPA, levels of TARC correlated positively with specific IgE to A. fumigatus and rAsp f4. Serum levels of TARC differentiate patients with CF or patients with asthma with ABPA from patients with CF colonized with or sensitized to A. fumigatus, atopic patients with CF, and atopic control subjects. Longitudinally, levels of TARC indicate ABPA exacerbations, suggesting TARC as a marker for identification and monitoring of ABPA in patients with CF.

Sensitization to Aspergillus Antigens and Occurrence of Allergic Bronchopulmonary Aspergillosis in Patients With Asthma

Sensitization to Aspergillus Antigens and Occurrence of Allergic Bronchopulmonary Aspergillosis in Patients With Asthma

Genetic and respiratory tract risk factors for aspergillosis: ABPA and asthma with fungal sensitization.

Allergic bronchopulmonary aspergillosis (ABPA) is a Th2 allergic hypersensitivity lung disease due to bronchial colonization of Aspergillus fumigatus that affects 1-2% of asthmatic and 7-9% of cystic fibrosis (CF) patients. We hypothesize that genetic risk factors predispose these patients to develop ABPA. We previously reported HLA-DR2 and DR5 restriction as a risk factor for the development of ABPA. We further propose that HLA-DR restriction is necessary but not sufficient for the development of ABPA. Recently, we reported that IL-4Rα single nucleotide polymorphisms (SNP) and in particular the ile75val SNP in the IL-4 binding region is another risk factor and is associated with increased sensitivity to IL-4 stimulation. It has been reported that the combination of IL-4Rα and IL-13 SNP, ile75val/arg110gln, is associated with more severe asthma. In preliminary studies, we have observed increased frequency of this combination in ABPA asthmatic and CF patients. Another genetic risk factor reported by Brouard et al. is the -1082 GG genotype in the IL-10 promoter in CF patients for the colonization of A. fumigatus and development of ABPA. This genotype was associated with increased plasma IL-10 levels, and perhaps may be associated with increased skewing of Th2 Aspergillus responses rather than down-regulation of inflammatory responses. We hypothesize that increased sensitivity of IL-4 mediated activities secondary to polymorphisms IL-4R in conjunction of other polymorphisms such as IL-13 and IL-10 in conjunction with HLA-DR2/DR5 restriction to Aspergillus antigens in ABPA patients result in increased B-cell activity, monocyte/dendritic cell phenotype that skews Th2 responses, and skewing of Aspergillus-specific Th2 cells. This model system may be applicable to other fungi such as Alternaria and Cladosporium which is associated with increased asthma severity.

Allergic bronchopulmonary aspergillosis in paediatric cystic fibrosis patients

Allergic bronchopulmonary aspergillosis (ABPA) is a severe complication in children, adolescents and adults with cystic fibrosis (CF), the prevalence of which ranges from 6-25%. The disease is the result of the colonisation of the respiratory tract by fungi of the genus Aspergillus, commonly Aspergillus fumigatus, and subsequent host sensitisation to fungal antigens, accompanied by a Th2 CD4 type response mediated by the production of specific IgE. The consequent inflammatory and obstructive bronchopulmonary injury can progress to fibrosis. The diagnosis should be considered early in patients with CF who show wheezing, transient pulmonary infiltrates and reduced lung function. The objective diagnosis is not straightforward because of overlapping clinical and radiological signs, particularly the progression of bronchiectasis. Specific criteria are needed for the diagnosis of ABPA in patients with CF, such as those proposed by the Cystic Fibrosis Foundation. The study of specific IgE against recombinant antigens of A. fumigatus has contributed to the early diagnosis of ABPA with high sensitivity and specificity. The technique has also shown promise in the follow-up of patients after steroid therapy and the early detection of recurrences. Treatment consists of long-term systemic corticosteroid usage, the monitoring of their adverse effects, and of the measurement of total serum IgE levels. The concomitant use of oral itraconazole seems to promote a better control of the disease and to reduce the duration of systemic steroid therapy but its use continues to be controversial. Controlled studies involving larger numbers of patients are necessary if we are to better understand the management of ABPA.

Allergic bronchopulmonary aspergillosis in a patient with cystic fibrosis: diagnostic criteria when the IgE level is less than 500 IU/mL

Recently, the Cystic Fibrosis Foundation developed a consensus report recommending diagnostic criteria for allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis that includes a serum IgE level greater than 500 IU/mL as the "minimal diagnostic criterion." To describe a 7-year-old girl with ABPA whose serum IgE level increased to only 398 IU/mL. Total IgE and anti-Aspergillus serologic measurements were performed using enzyme-linked immunosorbent assay and standard laboratory techniques; HLA analysis was performed; interleukin 4 receptor alpha single nucleotide polymorphisms were performed using polymerase chain reaction and DNA sequencing; CD23+ B cells were measured using flow cytometry; and cytokine synthesis to Aspergillus purified antigens was assessed using flow cytometry. A 7-year-old girl with cystic fibrosis who had mild pulmonary disease and well-controlled asthma developed pulmonary infiltrates, increased wheezing, and decreased pulmonary function. Additional studies demonstrated peripheral blood eosinophilia (eosinophil count, 1807 cells/mm3 [19%]) and an increase in IgE and IgG anti-Aspergillus serology; bronchoalveolar lavage revealed septate hyphae with 45 degrees branching subsequently identified as A fumigatus and pulmonary eosinophilia. Previous HLA typing revealed that the patient was HLA-DR2+, DRB*1501, HLA-DQ2-, a pattern associated with increased risk of ABPA. In addition, there was increased up-regulation of CD23 molecules by interleukin 4 stimulation on the patient's B cells, as observed in ABPA. The patient was treated with corticosteroids and itraconazole with resolution of symptoms and pulmonary infiltrates. Examination of the pulmonary inflammatory response using bronchoalveolar lavage, genetic risk with HLA-DR2+DQ2- typing, and increased interleukin 4 sensitivity are useful adjunctive studies in the diagnosis of ABPA.

Asp f6, an Aspergillus allergen specifically recognized by IgE from patients with allergic bronchopulmonary aspergillosis, is differentially expressed during germination

Aspergillus fumigatus is a pathogenic mould causing allergic and invasive respiratory diseases. Allergic bronchopulmonary Aspergillosis (ABPA) is a severe pulmonary complication resulting from hypersensitivity to A. fumigatus proteins. Aspergillus allergen Asp f6 is recognized by IgE from ABPA patients, but not from sensitized individuals, a fact that can be used to differentiate between these two groups of allergic patients. Proteins from hyphae, resting and germinating conidia of A. fumigatus were compared by SDS-PAGE. Protein identification was performed using MALDI-TOF mass spectrometry. Recombinant A. fumigatus allergens were used to isolate specific monoclonal antibodies (mab) from a hybridoma bank generated against Aspergillus proteins. A hyphae-specific 23 kDa A. fumigatus protein was identified as the allergen Asp f6/manganese-dependent superoxide dismutase (MnSOD). Differential expression of MnSOD was confirmed by immunoblot using a specific mab. In contrast, Asp f8 another intracellular, but not ABPA-specific allergen, was detected in hyphae and conidia. Aspergillus fumigatus is able to colonize its environment by the formation of hyphae. Hyphae are found in the lung of ABPA patients, but not in patients suffering from atopic asthma. Our finding that Asp f6 is specifically expressed in hyphae might explain why an IgE response to Asp f6 is specific for ABPA patients.

Tryptophan residue is essential for immunoreactivity of a diagnostically relevant peptide epitope of A. fumigatus

The role of tryptophan (Trp17) in immunoreactivity of P1, the diagnostically relevant peptide from a major allergen/antigen of Aspergillus fumigatus, was evaluated by chemically modifying tryptophanyl residue of P1. In BIAcore kinetic studies, unmodified P1 showed a 100-fold higher binding with ABPA (Allergic Bronchopulmonary Aspergillosis) patients' IgG [KD (equilibrium dissociation constant) = 2.74 e(-8) +/- 0.13 M] than the controls' IgG (KD = 2.97 e(-6) +/- 0.14 M), whereas chemically-modified P1 showed similar binding [KD patients' IgG = 3.25 e(-7) +/- 0.16 M, KD controls' IgG = 3.86 e(-7) +/- 0.19 M] indicating loss of specific immunoreactivity of P1 on tryptophan modification. Modified P1 showed loss of specific binding to IgE and IgG antibodies of ABPA patients in ELISA (Enzyme-Linked Immunosorbent Assay). The study infers that tryptophan residue (Trp17) is essential for immunoreactivity of P1.

Time course of antibody response to recombinant Aspergillus fumigatus antigens in cystic fibrosis with and without ABPA

We determined follow-up levels of specific serum IgE to the recombinant Aspergillus fumigatus (A. fumigatus) allergens rAsp f 1, 3, 4 and 6 in patients suffering from cystic fibrosis (CF) with and without allergic bronchopulmonary aspergillosis (ABPA). Over a 32-month period follow-up data of 74 patients were collected. According to serology, 11 CF patients were not sensitized (CF controls), 40 were sensitized to A. fumigatus (Asp. f-sens.) and 23 patients fulfilled the serologic criteria for ABPA. Of these 23 ABPA patients 11 expressed the full clinical ABPA picture (classicABPA) and 12 failed to show sufficient relevant clinical signs (seroABPA), despite positive serology. The 23 ABPA patients had 16-18 times higher serum levels of specific IgE to rAsp f 4 and/or rAsp f 6 than those of Asp. f-sens. patients (rAsp f 4: 31.3 +/- 45 EU/ml vs. 1.9 +/- 2.2 EU/ml and rAsp f 6: 39.0 +/- 44.3 EU/ml vs 2.1 +/- 1.7 EU/ml). The combination of increased total serum IgE (>1000 IU/l) and increased specific IgE to rAsp f 4 and/or rAsp f 6 allowed to diagnose classicABPA with 100% specificity and 64% sensitivity and with a high predicted positive (100%) and a high predicted negative (94%) value. During a combined treatment (seven patients) with oral corticosteroid and itraconazole, itraconazole alone (two patients) or neither oral corticosteroid nor itraconazole therapy (two patients) total serum IgE and specific IgE to rAsp f 4 and/or rAsp f 6 did decrease but did not normalize. Over the observation period, lung function remained unchanged, independent of whether oral steroids and/or concomitant itraconazole were either given or not given. In the follow-up of CF patients with ABPA under therapy the determination of total or specific IgE serum levels were of limited value to guide therapy.

Sensitization to Aspergillus Antigens and Occurrence of Allergic Bronchopulmonary Aspergillosis in Patients With Asthma

Background Allergic bronchopulmonary aspergillosis (ABPA), which is predominantly a disease of asthmatic subjects, is caused by hypersensitivity to Aspergillus antigens. Screening for Aspergillus sensitization in asthmatic subjects could identify those who are at risk for ABPA. Few studies have shown that fungal sensitization could be an important risk factor for asthma severity. We sought to determine the frequency of sensitization to Aspergillus antigens in asthmatic subjects and its effect on disease severity. We also determined the occurrence of ABPA in these subjects Design Prospective study of consecutive patients with asthma Setting Tertiary university referral hospital, outpatient department Patients and methods One hundred five asthmatic subjects and 26 volunteers underwent skin testing with aeroallergens, including Aspergillus, serum precipitins against Aspergillus antigens, and specific IgG against Aspergillus fumigatus , total serum IgE levels, and routine blood and radiologic investigations. ABPA was diagnosed when all eight major criteria were fulfilled Results Thirty patients (28.5%) had a positive skin reactivity to Aspergillus antigens. Eleven patients (10.4%) had positive specific reactions to IgG, and 8 patients (7.6%) demonstrated positive reactions to serum precipitins. Eight of these 30 patients (26.6%) received diagnoses of ABPA, which was 7.6% of the total. None of the control subjects were sensitized to Aspergillus antigens. The patients were classified into the following four groups: negative skin test results; positive reactions to aeroallergens other than Aspergillus; positive reactions to aeroallergens including Aspergillus antigens; and patients with ABPA. Based on clinical and serologic parameters, patients with Aspergillus-sensitive asthma and ABPA had a significantly more severe form of the disease Conclusions Sensitization to the mold Aspergillus increases the severity of asthma. ABPA should be excluded in all patients with Aspergillus-sensitive asthma

Role of collectins in innate immunity against aspergillosis

The protective role of lung surfactant proteins SP-A, SP-D and MBL in the host defense against both allergic and invasive aspergillosis was identified and established by a series of in vitro and in vivo studies. Therapeutic administration of SP-D and MBL proteins in a murine model of pulmonary invasive aspergillosis rescued mice from death. In mice mimicking human allergic bronchopulmonary aspergillosis, SP-A and SP-D suppressed IgE levels, eosinophilia, pulmonary cellular infiltration and cause a marked shift from a pathogenic Th2 to a protective Th1 cytokine profile. SP-A and SP-D knock-out mice studies made significant contributions in understanding the mechanisms by which SP-A and SP-D modulate the host defense response in patients suffering from pulmonary allergies and infections. The results suggested that individuals with any structural or functional defects in these innate immune molecules due to genetic variations might be susceptible to aspergillosis. SNPs in SP-A2 and MBL genes showed significant associations with patients of allergic bronchopulmonary aspergillosis in an Indian population. The patients carrying either one or both of GCT and AGG alleles of SP-A2 and patients with A allele at position 1011 of MBL had markedly higher eosinophilia, total IgE antibodies and lower FEV1 (the clinical markers of ABPA). Our results show that collectins play an important role in Aspergillus mediated allergies and infections.