| Title | Identification of the major allergen of Malassezia globosa relevant for atopic dermatitis. | | Author(s) | Ishibashi Y, Kato H, Asahi Y, Sugita T, Nishikawa A | | Institution | Department of Immunobiology, Meiji Pharmaceutical University, Tokyo, Japan. | | Source | J Dermatol Sci 2009 Sep; 55(3):185-92. | | MeSH | Adult
Amino Acid Sequence
Antigens, Fungal
Base Sequence
Cross Reactions
Dermatitis, Atopic
Female
HSP70 Heat-Shock Proteins
Humans
Immunoglobulin E
Malassezia
Male
Middle Aged
Molecular Sequence Data
Proteomics
Sequence Alignment
| | Abstract | BACKGROUND: Malasseziaglobosa constitutes a part of the normal flora of human skin, but may induce IgE production in atopic dermatitis (AD). However, information on M.globosa allergens is scant.
OBJECTIVE: To identify the major M. globosa allergens by using proteomic analysis.
METHODS: Immunoglobulin E (IgE) immunoblotting and cross-inhibition tests for M. globosa allergens were performed using sera from AD patients and control subjects. These allergens were identified and characterized using the proteomics approach involving a combination of two-dimensional (2D) electrophoresis, mass spectrometry, and bioinformatics tools. We cloned the cDNA of this allergen using sequences obtained by 5'- and 3'-rapid amplification of cDNA ends polymerase chain reaction.
RESULTS: The sera of the AD patients had IgE-reactive 40-45-kDa protein components. By 2D immunoblotting, we detected a 42-kDa protein spot with an isoelectric point (pI) of 4.8; the protein was highly reactive to IgE and was designated MGp42. Full-length MGp42 cDNA contained a 1908-bp open reading frame encoding 635 amino acid residues (calculated molecular mass, 69.7kDa; pI, 6.02). The N-terminal MGp42 sequence started from the 250th residue (Asp-250) of the deduced amino acid sequence and consisted of 386 amino acid residues; these results are consistent with those of 2D immunoblotting. MGp42 showed sequence similarity to members of the heat shock protein 70 (hsp70) family. Immunoblot inhibition tests revealed no IgE cross-reactivity between MGp42 and human HSP70.
CONCLUSIONS: MGp42 may be a cleavage product of intact HSP70. This novel M. globosa allergen could be useful for the diagnosis of AD. | | Language | eng | | Pub Type(s) | Journal Article
Research Support, Non-U.S. Gov't
| | PubMed ID | 19540092 |
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