Identification of a new natural Ara h 6 isoform and of its proteolytic product as major allergens in peanut.
J Agric Food Chem
; 55(23): 9663-9, 2007 Nov 14.
Article
in En
| MEDLINE
| ID: mdl-17949050
ABSTRACT
Numerous food allergens of plant origin belong to the 2S albumin family, including peanut Ara h 2. In addition to Ara h 2, several other conglutins related to 2S albumins are present in peanut seeds. We evaluated the allergenicity of different peanut conglutins as compared with Ara h 2. Several conglutins were isolated from the kernel, i.e. Ara h 2, a new isoform of Ara h 6 and its derived product, which is likely to be naturally formed during seed processing. Enzyme allergosorbent tests performed on sera of peanut allergic patients showed that more than 94% of 47 analyzed patients had positive IgE responses to Ara h 6 isoform and to its degradation product. Skin prick tests with the new isoform of Ara h 6 led to a positive response in seven out of the eight tested patients. Both enzyme allergosorbent tests and skin prick tests showed that the reactivity of Ara h 6 was similar to, or even higher than, that of Ara h 2, suggesting that the present isoform of Ara h 6 is as allergenic as Ara h 2. In addition the IgE response to the plant processed (i.e., hydrolyzed) Ara h 6 new isoform is equivalent to the IgE response to the native isoform. The IgE immunoreactivity is mostly abrogated by chemical reduction and denaturation of Ara h 6 isoforms, which underlined the importance of tertiary structure in Ara h 6 immunoreactivity. These results, and particularly the high correlation between anti-Ara h 2 and anti-Ara h 6 IgE responses, emphasise the major role of 2S albumins in peanut allergenicity.
Search on Google
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Allergens
/
Protein Isoforms
Type of study:
Diagnostic_studies
Limits:
Child
/
Female
/
Humans
/
Male
Language:
En
Journal:
J Agric Food Chem
Year:
2007
Type:
Article
Affiliation country:
France