Search PubMed⌕ Search

Biomedical subjects

J N Fink

Publications and source records attributed to J N Fink.

At least 37 records · Page 2Linked to original sources

IgE down regulation and cytokine induction by Aspergillus antigens in human allergic bronchopulmonary aspergillosis.

Allergic bronchopulmonary aspergillosis (ABPA), occurring primarily in patients with asthma or cystic fibrosis (CF), is a hypersensitivity reaction to Aspergillus fumigatus (Af), and is characterized by increased serum IgE levels and peripheral blood and pulmonary eosinophilia. We evaluated the IgE and cytokine profile in ABPA through enzyme-linked immunosorbent assay (ELISA), and evaluated eosinophil activity with the eosinophil peroxidase (EPO) assay. IgE and cytokines were measured in supernatants from cultures of peripheral blood mononuclear cells (PBMC) from three subject groups: ABPA patients, patients with asthma, and healthy individuals. All cultures for the three subject groups were studied in the presence and absence of two purified Af antigens (the 35-kD antigen and heat shock protein 1). We found that increased in vitro levels of IgE in unstimulated PBMC culture supernatants correlated significantly with serum IgE concentrations in ABPA patients. We measured a decrease in IgE levels of up to 75% of baseline values in supernatants from PBMC cultured with Af antigens. Interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) concentrations in cultures with Af were increased in ABPA, whereas concentrations of IL-4 did not differ in the three subject groups. An inverse relation was noted between the changes in IgE and IFN-gamma measured in 4 of 5 ABPA patients. The PBMC supernatants also promoted EPO activity in purified eosinophils from ABPA patients, and to a lesser extent in purified eosinophils from healthy subjects. These results show that the 35-kD antigen and HSP1 from Af downregulate IgE in vitro but are capable of inducing eosinophilia in ABPA. Further studies could result in the characterization of epitopes leading to these disparate effects. An identification of the IgE-down-regulating epitopes in Af antigens might have therapeutic significance.

Adult↗

Evaluation of a non-chlorofluorocarbon formulation of cromolyn sodium (Intal) metered-dose inhaler versus the chlorofluorocarbon formulation in the treatment of adult patients with asthma: a controlled trial.

BACKGROUND: Cromolyn sodium is a nonsteroidal inhaled antiinflammatory agent for the treatment of asthma. As with other pressurized aerosol medications, the metered-dose inhaler (MDI) formulation currently contains chlorofluorocarbon (CFC) propellants. Because of their harmful effects on the environment CFCs are now generally banned from production and use. Alternative propellants under production for MDIs include derivatives of hydrofluoroalkane (HFA). This study uses HFA-227 in an MDI formulation of cromolyn sodium. OBJECTIVES: The objectives of the study were (1) to examine the efficacy and safety of an HFA formulation of cromolyn sodium (Intal) MDI and (2) to compare the HFA formulation with the CFC formulation. METHODS: A multicenter, randomized, double-blind, placebo-controlled, parallel study with two active groups (HFA-cromolyn sodium [n = 113] and CFC-cromolyn sodium [n = 107]) and a placebo-treated group (n = 105). RESULTS: Patients treated with either formulation of cromolyn sodium MDI showed a statistically significant (p < 0.05) improvement of 12% to 18% compared with placebo in symptom summary score, daytime asthma symptoms, and albuterol use. No statistically significant differences were observed in pulmonary function. Patient and physician opinions of overall effectiveness favored HFA-cromolyn sodium over placebo (p = 0.01), with no other significant between-treatment differences. No statistically significant differences existed among groups in the incidence of treatment-related adverse events. CONCLUSION: The HFA formulation of cromolyn sodium MDI is a well- tolerated and active alternative treatment for asthma patients aged 12 years and more.

Administration, Inhalation↗

Immunodominant peptide epitopes of allergen, Asp f 1 from the fungus Aspergillus fumigatus.

Aspergillus fumigatus ribotoxin Asp f 1 is a major allergen with IgE binding activity to serum of a majority of patients with allergic bronchopulmonary aspergillosis (ABPA). The IgE binding epitopes or the T-cell stimulatory peptides of this molecule have not been studied. In the present investigation, we have synthesized linear decapeptides spanning the whole molecule of Asp f 1 and analyzed their IgE binding properties. We have also synthesized peptides based on their possible T-cell stimulatory properties and studied the stimulation of peripheral blood mononuclear cells from ABPA patients and normal controls. Several peptides demonstrated distinct IgE antibody binding response against sera from ABPA patients and proliferative response against peripheral blood mononuclear cells from the patients. From the results, it can be concluded that the carboxy-terminal region of Asp f 1 representing amino acid residues 115-149 involved in both humoral and cell mediated immunoresponses in ABPA.

Allergens↗

The spectrum of respiratory disease associated with exposure to metal working fluids.

Occupational respiratory diseases have been reported following exposure to metal working fluids. We report a spectrum of respiratory illnesses occurring in an outbreak in 30 workers of an automobile parts engine manufacturing plant. Workers presented with respiratory complaints and, after clinical and laboratory evaluations, were classified as those having hypersensitivity pneumonitis, occupational asthma, or industrial bronchitis, or those without occupational lung disease. Hypersensitivity pneumonitis affected seven workers, with six exhibiting serum precipitins to Acinetobacter Iwoffii. Occupational asthma and industrial bronchitis affected 12 and six workers, respectively. Oil-mist exposures were below current recommendations. Gram-negative bacteria, but no fungi, Thermophiles, or Legionella, were identified. Although specific agents responsible for each individual case could not be identified, probably both specific sensitizing agents and non-specific irritants from metal working fluids, additives, or contaminants contributed to this spectrum of occupational respiratory illness.

Adult↗

Immunological characterization of Asp f 2, a major allergen from Aspergillus fumigatus associated with allergic bronchopulmonary aspergillosis.

The 37-kDa recombinant protein Asp f 2, encoding an allergen of Aspergillus fumigatus, was expressed in a prokaryotic expression system and immunologically evaluated for its functional and structural properties. The open reading frame for a 310-amino-acid-long protein was shown to encode a signal peptide of 31 amino acids. A native 37-kDa culture filtrate protein and a 55-kDa mycelial glycoprotein (gp55) exhibited complete N-terminal sequence homology to Asp f 2. A GenBank search for homologous proteins revealed 60 and 44% sequence homologies to the cytosolic protein ASPND1 from Aspergillus nidulans and fibrinogen binding protein from Candida albicans, respectively. The glycosylation sites and cysteine molecules are conserved in all the three proteins. The extracellular matrix protein laminin showed a dose-dependent interaction with Asp f 2. This protein, expressed as a major cell-associated protein within 24 h of in vitro fungal culture, comprises 20 to 40% of total fungal protein. Furthermore, both native and recombinant Asp f 2 exhibited specific immunoglobulin (IgE) binding with allergic bronchopulmonary aspergillosis (ABPA) and cystic fibrosis-ABPA patients, whereas A. fumigatus-sensitized allergic asthma and normal control subjects failed to show IgE binding with Asp f 2. These results indicate that Asp f 2 is a major allergen of A. fumigatus exhibiting IgE antibody binding with sera from patients with ABPA. The antigen should be explored further for its potential role in the differential diagnosis of A. fumigatus-associated allergic diseases.

Allergens↗

IgE from latex-allergic patients binds to cloned and expressed B cell epitopes of prohevein.

Prohevein is one of the major allergens associated with latex allergy. In the present study, we identified IgE binding regions of prohevein, and expressed multiple IgE binding epitopes by selective cloning. These truncated polypeptides were then used to demonstrate IgE in the sera of patients. Decapeptides of prohevein were synthesized on derivatized cellulose membrane with an offset of one amino acid. The IgE reactivity of these linear peptides was evaluated separately using pooled sera from latex-allergic health care workers (HCW) and spina bifida (SB) patients. A total of 10 IgE binding epitopes representing unique as well as shared epitopes from both the N- and C-domains of the prohevein were identified. Recombinant polypeptides were constructed based on the identified epitopes, and clones carrying DNA fragments were overexpressed. These recombinant peptides were evaluated for IgE binding with sera from HCW, SB, and normal individuals. Recombinant prohevein, hevein, and the C-domain exhibited IgE binding in 84, 88, and 40% of HCW sera, respectively, as against reactivity of 84% with crude latex allergens. However, only 48% of the sera from SB patients showed IgE binding with recombinant prohevein, while 56 and 28% had reactivity with recombinant N- and C-domains, respectively. Among the three remaining recombinant peptides of the C-domain, only CA44-103 showed IgE binding with SB patients. The results of the present study suggest that linear IgE epitope analysis and construction of recombinant peptides increase the sensitivity and specificity of the immunodiagnosis of latex allergy and provide more information on the immunopathogenesis of hypersensitivity reaction mediated by type I allergy.

Allergens↗

Development of bone marrow eosinophilia in mice induced by Aspergillus fumigatus antigens.

A model of allergic bronchopulmonary aspergillosis (ABPA) developed by exposing mice to Aspergillus fumigatus antigen (Af) exhibits peripheral blood (PB), lung, and bone marrow (BM) eosinophilia. Because the BM is a site of eosinophilopoiesis, we have investigated the role of Af in the induction of this process in the BM. Groups of mice were exposed intranasally (i.n.) or intraperitoneally (i.p.) to Af. BM cells from mice were cultured with either Af or allogenic spleen cell supernatant stimulated with Af. Eosinophil counts in different lymphoid compartments, eosinophil peroxidase (EPO), and mRNA for cytokines and IgE in BM cells were studied. Results indicate that the eosinophil numbers were significantly elevated in PB and BM of all Af-exposed mice. Lung lavage eosinophils increased only in the i.n. group. Af induced EPO activity only in BM cultures from Af-exposed mice. The EPO activity was further enhanced by supernatants from spleen cells from Af-exposed mice. mRNA transcription of IL-3 and IL-5 were measurable in BM cells of the ip exposed mice. These findings suggest that Af mediates eosinophil development in BM of mice and this process is promoted by hematopoietic factors generated within the BM and in other lymphoid tissue such as the spleen.

Animals↗

Immunopathologic responses to Aspergillus antigen in interleukin-4 knockout mice.

Two strains of interleukin-4 (IL-4) gene knockout mice were studied and compared with wild strains to determine the role of IL-4 in the immunopathogenesis of murine allergic aspergillosis. Animals immunized intraperitoneally were subsequently challenged with Aspergillus antigen intranasally. The animals were evaluated for total serum immunoglobulin E (IgE) levels, Aspergillus-specific IgG antibody isotypes, peripheral blood eosinophils, cytokine and chemokine mRNA transcripts in spleen cells, and pulmonary histology. No serum IgE was detected in animals deficient in the IL-4 gene. Aspergillus-specific IgG1 was detected in all animals, while enhanced levels of IgG2a were detected in IL-4 knockout animals challenged with A. fumigatus antigen. There were no differences in the peripheral blood or lung eosinophils in the two groups of mice exposed to A. fumigatus. These results indicate that lung injury in Aspergillus-antigen challenged animals may be the result of the eosinophil mediators and that IgE-mediated injury may not be significant in this model, which may be a significant variation between the model and human allergic aspergillosis.

Animals↗

Purification of a major allergen, Asp f 2 binding to IgE in allergic bronchopulmonary aspergillosis, from culture filtrate of Aspergillus fumigatus.

BACKGROUND: Most cases of allergic bronchopulmonary aspergillosis (ABPA) are caused by the fungus Aspergillus fumigatus. Successful treatment of this disease depends on early diagnosis with the use of well-characterized and relevant antigens/allergens of the organism. OBJECTIVE: The aim of this study was to purify and characterize relevant proteins from A. fumigatus that could be used in the reliable diagnosis of ABPA. METHODS: Monoclonal antibodies were raised against A. fumigatus culture filtrate antigens. A Concanavalin A nonbinding protein fraction was purified with use of one of the monoclonal antibody immunoaffinity columns. The purified protein was analyzed on sodium dodecylsulfate-polyacrylamide gel electrophoresis gel and Western blots. The sensitivity and specificity of the purified protein were evaluated by RAST and ELISA with sera from 25 patients with ABPA, from 10 with allergic asthma, and from 10 normal control subjects. RESULTS: The 37 kD Concanavalin A nonbinding protein reacted specifically with IgE antibodies in patients with ABPA. Among the 25 patients with ABPA studied, 96% had IgE antibody against the allergen, whereas none of the subjects with allergic asthma who had positive results on the skin prick test or normal control subjects had a reaction. Both RAST and ELISA results exhibited strong correlation with IgE binding. This allergen exhibited N-terminal sequence identity to a recombinant allergen Asp f 2. CONCLUSIONS: A 37 kD protein with complete N-terminal homology to Asp f 2 is a major allergen of A. fumigatus that significantly reacts with IgE antibody in patients with ABPA, but does not elicit reaction in Aspergillus-sensitive subjects with asthma and normal control subjects.

Allergens↗

Anti-interleukin (IL)-4 and -IL-5 antibodies downregulate IgE and eosinophilia in mice exposed to Aspergillus antigens.

The effect of multiple divided doses compared with single-dose injections of antibodies to murine interleukin (IL)-4 and IL-5 in their respective downregulation of IgE and eosinophilia developing in a model of allergic aspergillosis is investigated. BALB/c mice were exposed to Aspergillus fumigatus antigens (Af) before and along with anticytokine antibodies. The kinetics of blood eosinophils, eosinophil peroxidase (EPO) in bone-marrow cells, serum levels of IgE and Af-specific antibodies, Af-induced cytokine production and mRNA, and lung histology were studied. The results indicate that only multiple anti-IL-5 antibodies were effective in maintaining baseline levels of blood eosinophils. Multiple anti-IL-4 antibodies also downregulated eosinophils in the bone marrow, lung, and peripheral blood, although to a lesser extent than in anti-IL-5 antibody-injected mice. Significant correlation between the EPO activity and the eosinophil numbers in anticytokine antibody-treated mice was observed. The different anti-IL-4 antibody treatments downregulated IgE to the same extent. We conclude that multiple divided doses of anti-IL-5 antibodies are required to sustain normal eosinophil levels in murine allergic aspergillosis. This information may be significant in the therapy of pulmonary allergic diseases.

Animals↗

Role of particulate antigens of Aspergillus in murine eosinophilia.

OBJECTIVE: Allergic bronchopulmonary aspergillosis, a disabling hypersensitivity lung disease, results from inhalation of Aspergillus fumigatus antigens present in contaminated environments. A murine model has been developed to understand the immune mechanism involved in allergic bronchopulmonary aspergillosis. We have investigated the immunoregulatory role of different physical forms of A.fumigatus antigens, such as A.fumigatus spores, soluble antigens. and soluble antigen coupled inert particles, in the model. METHODS: BALB/c mice were exposed to soluble A.fumigatus antigens, spores, or inert particles of comparable size to the spores coupled with A.fumigatus soluble antigens. Antibody and eosinophil response, pulmonary pathology, and cytokine expressions were studied. RESULTS: Peripheral blood eosinophilia and pulmonary inflammation with influx of eosinophils into the lung was detected more in animals exposed to particulate antigens than in those exposed to soluble antigen. However, the total serum IgE and Aspergillus-specific IgG levels showed only a slight increase in the former groups as opposed to elevated levels in animals exposed to soluble antigen. The cytokine expression in in vitro antigen stimulated spleen cells showed a typical Th2 pattern in all antigen-exposed animals. IL-5 mRNA could be detected in the spleen cells cultured with antigen from all groups of antigen-exposed animals. CONCLUSION: Particulate A.fumigatus antigens induced eosinophilia in mice prior to the elevation of serum IgE levels. This pattern of IgE and eosinophilia is reversed with the soluble antigen exposure in this model.

Animals↗

Aspergillus fumigatus peptides differentially express Th1 and Th2 cytokines.

Relevant allergens from Aspergillus fumigatus associated with allergic bronchopulmonary aspergillosis (ABPA) have been cloned and expressed. The pathogenesis of ABPA probably depends on specific cytokines and immunoglobulins secreted by lymphocytes on stimulation with different epitopes of those allergens. In the present study, we synthesized peptides of 12-16 amino acids from the sequence of Asp fI and compared their immunological responses in four mice strains (BALB/c, C57BL/6, AKR, and CBA). Of the five peptides studied for their cytokine profile, one showed a clear Th1, whereas another showed a Th2 response. The remaining three peptides varied in their immunoreactivity. The results suggest that a number of epitopes of diverse activities are present in individual molecules and may be involved in the pathogenesis of ABPA through differential cytokine secretions.

Allergens↗

Molecular cloning and expression of a recombinant Aspergillus fumigatus protein Asp f II with significant immunoglobulin E reactivity in allergic bronchopulmonary aspergillosis.

The cDNA of Aspergillus fumigatus encoding an allergen was cloned and expressed in Escherichia coli. The 987 bp long cDNA clone expressed a recombinant protein Asp f II of 34 kd. This protein exhibited binding to immunoglobulin E (IgE) in the serum samples from patients with allergic bronchopulmonary aspergillosis (ABPA). The patients with ABPA and central bronchiectasis demonstrated high levels of serum IgE antibodies, whereas patients with ABPA without central bronchiectasis, patients with asthma and Aspergillus skin test reactivity but no evidence of ABPA, and patients with aspergilloma showed only low levels of IgE antibody to Asp f II. In two-dimensional electrophoresis, a native antigen electroeluted from an A. fumigatus culture filtrate antigen preparation showed an isoelectric point and molecular weight similar to that of Asp f II. In a competitive enzyme-linked immunosorbent assay (ELISA), the IgE antibody reactivity of Asp f II with patient serum samples could be significantly inhibited by culture filtrate antigens of A. fumigatus. These results indicate that Asp f II has immunologic reactivities comparable to those of native A. fumigatus antigens. The recombinant Asp f II can be expressed in E. coli in large quantities and should prove useful as a standardized allergen for sensitive and specific immunodiagnosis of ABPA, especially in patients with central bronchiectasis.

Animals↗

Comparative studies of latex extracts used in skin testing.

BACKGROUND: There has been considerable variability reported in latex extracts used for skin testing and the results of those skin tests in the evaluation of latex allergy. Some test extracts have been associated with the induction of anaphylactic reactions in sensitive patients, while others have been reported as without adverse reactions. OBJECTIVE: The present study was designed to evaluate late extracts by comparing antigens from latex gloves. METHODS: Latex gloves were extracted for from 15 minutes to 24 hours for their protein contents and in vitro reactivities with IgE antibodies using sera of latex allergic patients and controls by ELISA. RESULTS: A higher yield of proteins was obtained after prolonged extraction, although reactivity of the sera by ELISA showed no major differences among the extracts. Extracts of 15 minutes elicited stronger reaction with health care workers and patients with spina bifida than with 24-hour extracts. The 15-minute extract demonstrated comparatively more reactive antigenic components in the fractions representing 3 to 10 and 10 to 30-kDa compared with fractions having less than 3 and over 30-kDa antigens. CONCLUSION: The study provided no evidence regarding the safety of one latex extract over the other related to time of extraction. The results indicated that a 15-minute extract can be used in ELISA for in vitro and, as in the literature, safe in vivo demonstration of latex specific IgE antibody.

Antigen-Antibody Reactions↗

A two-dimensional electrophoretic analysis of latex peptides reacting with IgE and IgG antibodies from patients with latex allergy.

Latex proteins from nonammoniated natural rubber latex were investigated for their reactivity with antibodies in the sera of patients with spina bifida and health care workers with allergy to latex. Immunoblots of two-dimensional electrophoresis were used to compare the reactivity of various polypeptides against IgE, IgG, and subclasses of IgG. A total of 79 polypeptides showed reactivity with IgG and IgE antibodies from different patients. IgG showed reactivity with all the 79 polypeptides, while IgE reacted with 56 allergens. IgG2 reacted with the least number of proteins, while IgG4 reacted with the largest number of polypeptides. Several antigens were identified as significant due to their reactivity with antibodies in latex-allergic patients. Four proteins reacted with IgE, IgG1, IgG3 and IgG4 of only spina bifida patients with latex allergy, while one other protein reacted only with health care workers. Thus, these relevant latex peptides may be isolated, purified, and used in various assays for more reliable diagnosis of latex allergy.

Adolescent↗

Characterization of a major latex allergen associated with hypersensitivity in spina bifida patients.

Hypersensitivity to latex proteins present in health care products, particularly in latex gloves, has emerged as an important public health problem in recent years. Most of these latex allergens have not been purified or characterized. Here we report the purification and characterization of a 23-kDa latex polypeptide from nonammoniated natural rubber latex. This purified 23-kDa polypeptide reacted with IgE from 13 of 17 (76%) latex-allergic spina bifida patients, but from only 1 of 5 health care workers with latex allergy. Furthermore, all the sera of patients with anaphylaxis to latex showed reactivity with the 23-kDa polypeptide. This allergen also induced significant lymphocyte proliferation by PBMC from spina bifida patients, but not from health care workers. The 90 amino acid residues sequenced from the 23-kDa polypeptide showed a 45.6% homology with a previously reported latex protein, rubber elongation factor. By using a mAb LAM-1, produced against the 23-kDa allergen, we could also detect this allergen or its epitope in ammoniated latex and natural rubber latex products used in health care management, but not in non-latex extracts studied.

Allergens↗