Carrier-bound Alt a 1 peptides without allergenic activity for vaccination against Alternaria alternata allergy.
ABSTRACT The mould Alternaria alternata is a major elicitor of allergic asthma. Diagnosis and specific immunotherapy (SIT) of Alternaria allergy are often limited by the insufficient quality of natural mould extracts.
To investigate whether recombinant Alt a 1 can be used for reliable diagnosis of Alternaria alternata allergy and to develop a safe, non-allergenic vaccine for SIT of Alternaria allergy.
The qualitative sensitization profile of 80 Alternaria-allergic patients from Austria and Italy was investigated using an allergen micro-array and the amount of Alternaria-specific IgE directed to rAlt a 1 was quantified by ImmunoCAP measurements. Peptides spanning regions of predicted high surface accessibility of Alt a 1 were synthesized and tested for IgE reactivity and allergenic activity, using sera and basophils from allergic patients. Carrier-bound peptides were studied for their ability to induce IgG antibodies in rabbits which recognize Alt a 1 and inhibit allergic patients' IgE reactivity to Alt a 1.
rAlt a 1 allowed diagnosis of Alternaria allergy in all tested patients, bound the vast majority (i.e. >95%) of Alternaria-specific IgE and elicited basophil activation already at a concentration of 0.1 ng/mL. Four non-allergenic peptides were synthesized which, after coupling to the carrier protein keyhole limpet hemocyanin, induced Alt a 1-specific IgG and inhibited allergic patients' IgE binding to Alt a 1.
rAlt a 1 is a highly allergenic molecule allowing sensitive diagnosis of Alternaria allergy. Carrier-bound non-allergenic Alt a 1 peptides are candidates for safe SIT of Alternaria allergy.
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Article: Vaccines for allergy.[show abstract] [hide abstract]
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ABSTRACT: Alt a 1 is the major allergen of the fungus Alternaria alternata and can be found in the cell wall of its spores. It is a cysteine linked homodimeric protein with a unique β-barrel fold as recently revealed by X-ray crystallography. Despite the elucidation of its structure, its biological function remains unknown. For Alternaria-sensitized patients, contact leads to respiratory allergy and in severe cases to asthma-related death. Here we report the sequence-specific Alt a 1 backbone (1)H, (15)N and (13)C chemical shift assignment.Biomolecular NMR Assignments 05/2013; · 0.64 Impact Factor
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