title: Alt a 15 is a new cross-reactive minor allergen of Alternaria alternata.
abstract: Alternaria alternata is one of the most common saprophytes worldwide that is clinically and epidemiologically associated with severe asthma. Therefore, the identification and characterization of all A. alternata allergens are of major clinical importance. This study describes a new cross-reactive A. alternata allergen that was officially named Alt a 15 by the official Allergen Nomenclature Subcommittee. The complete coding region for Alt a 15 was amplified using 5' and 3' rapid amplification of cDNA ends and PCR. The recombinant protein was produced in Escherichia coli as a 65-kDa fusion protein, and the protein sequence exhibits high homology with several important fungal allergens. Immunoblotting analyses revealed that IgE antibodies from A. alternata-sensitized patients (n=59) bound to rAlt a 15 with a prevalence of 10.2%. All patients who presented sIgE to rAlt a 15 were apparently poly-sensitized to A. alternata and C. lunata. The extensive cross-reactivity between A. alternata and C. lunata serine proteases was confirmed using immunoblotting inhibition assays. Overall, Alt a 15 is an important new cross-reactive allergen of A. alternata that explains some allergies to A. alternata without Alt a 1 sensitization and initial diagnostic errors for allergies to Alternaria. This molecule may improve the accuracy of the diagnosis, the understanding, and the management of IgE-mediated fungal diseases.
authors.affiliation: Department of Immunology, Microbiology and Parasitology, Faculty of Pharmacy and Laboratory of Parasitology and Allergy, Lascaray Research Centre, University of the Basque Country, Vitoria, Spain; Department of Chemistry and CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.
authors.forename: M F
authors.initials: MF
authors.lastname: Gabriel
authors.affiliation: Department of Immunology, Microbiology and Parasitology, Faculty of Pharmacy and Laboratory of Parasitology and Allergy, Lascaray Research Centre, University of the Basque Country, Vitoria, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Postigo
authors.affiliation: Department of Immunology, Microbiology and Parasitology, Faculty of Pharmacy and Laboratory of Parasitology and Allergy, Lascaray Research Centre, University of the Basque Country, Vitoria, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Gutiérrez-Rodríguez
authors.affiliation: Department of Immunology, Microbiology and Parasitology, Faculty of Pharmacy and Laboratory of Parasitology and Allergy, Lascaray Research Centre, University of the Basque Country, Vitoria, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Suñén
authors.affiliation: Department of Immunology, Microbiology and Parasitology, Faculty of Pharmacy and Laboratory of Parasitology and Allergy, Lascaray Research Centre, University of the Basque Country, Vitoria, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Guisantes
authors.affiliation: Allergy Section, University General Hospital of Alicante and Department of Medicine of the University Miguel Hernández, Alicante, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Fernández
authors.affiliation: Department of Chemistry and CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.
authors.forename: C T
authors.initials: CT
authors.lastname: Tomaz
authors.affiliation: Department of Immunology, Microbiology and Parasitology, Faculty of Pharmacy and Laboratory of Parasitology and Allergy, Lascaray Research Centre, University of the Basque Country, Vitoria, Spain. Electronic address: jorge.martinez@ehu.es.
authors.forename: J
authors.initials: J
authors.lastname: Martínez
mesh_terms: D000485:Allergens / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D000528:Alternaria / Q000737:chemistry / Q000276:immunology*; D000595:Amino Acid Sequence; D000908:Antibodies, Fungal / Q000737:chemistry* / Q000302:isolation & purification; D000918:Antibody Specificity; D000946:Antigens, Fungal / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D001249:Asthma / Q000139:chemically induced / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D003001:Cloning, Molecular; D003429:Cross Reactions; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D007073:Immunoglobulin E / Q000737:chemistry* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011485:Protein Binding; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D016415:Sequence Alignment
chemical_list: D000485:Allergens; D000908:Antibodies, Fungal; D000946:Antigens, Fungal; D011994:Recombinant Proteins; D007073:Immunoglobulin E
keywords: Alternaria alternata; Cross-reactivity; Fungal allergy; Recombinant allergen; Vacuolar serine protease; cDNA cloning