Cloning and expression of Aspergillus fumigatus allergen Asp f 16 mediating both humoral and cell-mediated immunity in allergic bronchopulmonary aspergillosis (ABPA). Clin Exp Allergy 2001 May;31(5):761-70
Date
06/26/2001Pubmed ID
11422136DOI
10.1046/j.1365-2222.2001.01076.xScopus ID
2-s2.0-0034840298 (requires institutional sign-in at Scopus site) 48 CitationsAbstract
BACKGROUND: Aspergillus fumigatus, a ubiquitous fungus, is responsible for a number of lung disorders in atopic and non-atopic individuals. Standardized, pure, and relevant allergens are desirable for reliable immunodiagnosis of the disease and to understand the structural and functional properties of these allergens and the role they play in causing ABPA.
OBJECTIVE: Molecular cloning and characterization of a relevant allergen from A. fumigatus cDNA library.
MATERIALS AND METHODS: A cDNA library was constructed from 96 h old mycelium of A. fumigatus using lambda ZAP expression vector. A novel gene encoding an A. fumigatus allergen was identified by screening the library with sera from ABPA patients. The gene was cloned and the allergen over-expressed in Escherichia coli. This recombinant allergen, Asp f 16, was evaluated in ELISA and Western blots using sera from patients and normal subjects and peripheral blood mononuclear cells (PBMC) for antigen-induced stimulation.
RESULTS: Seventy percent of the patients with ABPA demonstrated high levels of serum IgE antibodies to Asp f 16, a 43-kDa protein, whereas patients with allergic asthma, Aspergillus skin test-positive asthmatics without clinical evidence of ABPA, and normal controls failed to show Asp f 16-specific IgE binding by ELISA. The deduced amino acid sequences of Asp f 16 showed extensive sequence homology to 30.6-kDa Asp f 9 at the N-terminal region of the protein. PBMC from the majority of patients with ABPA exhibited significant proliferation with the recombinant Asp f 16 allergen.
CONCLUSION: Specific humoral and cell-mediated immune responses of Af-sensitized patients against Asp f 16 suggest its usefulness in the immunodiagnosis of hypersensitivity diseases due to Af and understanding the pathophysiology of ABPA.
Author List
Banerjee B, Kurup VP, Greenberger PA, Johnson BD, Fink JNAuthors
Banani Banerjee PhD Associate Professor in the Medicine department at Medical College of WisconsinBryon D. Johnson PhD Adjunct Professor in the Medicine department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AllergensAmino Acid Sequence
Antibody Formation
Antibody Specificity
Antigens, Fungal
Antigens, Plant
Aspergillosis, Allergic Bronchopulmonary
Aspergillus fumigatus
Base Sequence
Blotting, Western
Cloning, Molecular
Electrophoresis, Polyacrylamide Gel
Enzyme-Linked Immunosorbent Assay
Fungal Proteins
Humans
Immunity, Cellular
Immunization
Immunoglobulin E
Molecular Sequence Data
Sensitivity and Specificity
Skin Tests