| Autor: |
Alberto Martínez, I. Ibarrola, Juan A. Asturias, M. C. Arilla, Elena Eraso |
| Rok vydání: |
2003 |
| Předmět: |
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| Zdroj: |
Clinical & Experimental Allergy. 33:978-985 |
| ISSN: |
0954-7894 |
| DOI: |
10.1046/j.1365-2222.2003.01707.x |
| Popis: |
Summary Background Sycamores or plane trees are an important source of airborne allergens in many cities of the United States and Western Europe. Pla a 1 has been described as a major allergen from Platanus acerifolia (London plane tree). Objective To clone and characterize the cDNA for Pla a 1 and to express the recombinant protein. Methods Pla a 1 was isolated by cationic exchange, gel filtration, and reverse-phase chromato-graphies. Pla a 1 cDNA was cloned by reverse transcription followed by polymerase chain reaction, using amino acid sequences from tryptic peptides of the allergen. The Pla a 1 encoding sequence has been subcloned into the pKN172 expression vector and expressed in Escherichia coli as a non-fusion protein. Purified recombinant protein has been tested for its IgE-binding capacity in immunoblot, immunoblot inhibition, and ELISA. Results Pla a 1 reacted with serum IgE from 35 of the 42 (83.3%) Platanus-allergic patients studied and represented 60% of the total IgE-binding capacity of the P. acerifolia pollen extract. The allergen displayed 43% sequence identity to a grape invertase inhibitor and showed a predicted secondary structure characteristic of all-alpha proteins. Serological analysis revealed that both natural and recombinant forms of Pla a 1 displayed similar IgE-binding capacity. Conclusions Pla a 1 belongs to a new class of allergens related to proteinaceous invertase inhibitors. Recombinant Pla a 1 binds IgE in vitro like its natural counterpart and, therefore, it can be useful for specific diagnosis and structural studies. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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