Effect of hypoallergenic wheat (HAW-A1) on atopic dermatitis (AD) with wheat allergy, and its antigenic analysis using sera from patients with AD

Wheat allergy has been suggested to be played an important role in the development and exacerbation of the severe type of atopic dermatitis (AD) in some cases. In this paper, we fractionated wheat antigenic proteins to salt-soluble and salt-insoluble fractions and assayed the IgE antibody titers against each fraction using AD patients' sera, indicating that the salt-soluble fraction has potential of major allergenicity. Then we prepared a hypoallergenic wheat flour (HAW-A1) by decomposition of the salt-soluble fraction using the salt solution washing procedure, and examined the hypoallergenicity of HAW-A1 in IgE-ELISA and IgE-immunoblotting with wheat-RAST positive AD's sera. The results were confirmed that most components of the salt-soluble proteins containing allergenic protein bands are decomposed from HAW-A1, and no IgE antibody titer could be detected in AD patients' sera. The next, the clinical usefulness of this hypoallergenic wheat (HAW-A1) was evaluated in 18 subjects with recalcitrant AD, who were suspected of having wheat allergy. In 15 of the 18 AD subjects tested, HAWN is very useful as a substitute of wheat foods, and in 11 of these patients has higher titers of IgE antibodies against the salt-soluble than salt-insoluble fractions which were extracted from regular wheat flour, and in 4 of these patients also have undetectable levels of IgE antibodies against either fraction. On the other hand, in 3 of 18 AD subjects who revealed positive reaction to HAWN ingestion as same as to regular wheat ingestion, and IgE antibodies to salt-insoluble proteins remaining in HAW-A1, were found. These results indicate that HAW-A1 is very useful as a substitute for wheat food, least in AD patients with wheat allergy who have high titers of IgE antibodies against the salt-soluble than salt-insoluble fractions, and who also have undetectable levels of IgE antibodies against the both fractions.