Sensitization to acid-hydrolyzed wheat protein by transdermal administration to BALB/c mice, and comparison with gluten.(1)
Wheat-dependent exercise-induced anaphylaxis (WDEIA) is one of the most important clinical phenotypes of adult wheat allergy. Recently, immediate hypersensitivity to hydrolyzed wheat protein (HWP) was reported. Generally it is believed that hydrolysis reduces the allergenicity of allergenic proteins. However HWP induces immediate hypersensitivity by skin contact and/or food ingestion has increased. Hydrolyzed wheat protein, mainly consisting of hydrolyzed gluten, is widely used in cosmetics. Hydrolyzed gluten is a mixture of variously sized polypeptides, and their sizes depend on the condition of hydrolysis.
The IgE contents of HS, H, and GS groups were significantly increased compared with that of the vehicle group, while the content in G group was barely increased. The IgG1 contents of HS, H, and GS groups were also significantly higher than that of the vehicle group. At HWP1 doses of 20–500 lg/mouse, both IgE and IgG1 contents were clearly increased dose dependently.
The IgE contents of GS, HS, and H groups were significantly increased compared with that of the vehicle group, while the content in G group was barely increased. The IgG1 contents of GS, G, and H groups were significantly increased, although there were some individual differences in G group. The difference in antibody content between GS and G groups showed that SDS played an important role in sensiti- zation by transdermal administration.
Among the four groups, mice in HS, H, and GS groups immediately reacted to their antigens. After 30 min, average rectal temperatures of mice in HS, H, and GS groups decreased to approximately 3.5, 2.6, and 2.1°C, respectively, which were lower than that of the vehicle group.
There was little or no anaphylactic response in all mice in vehicle and G groups. In GS group, half of the mice showed mild to slightly severe responses (score 1–3), while the other mice showed no responses. All the mice in H group exhibited mild to slightly severe symp- toms (score 2–3). In HS group, half of the mice experienced severe symptoms (score 4).
The mean value of histamine content in H group was significantly higher than that of the vehicle group. Larger amounts of HWP1 used for sensitization resulted in a higher histamine content in mouse plasma.
In HS100 and HS500 groups, the content of IL-4, IL- 5, and IL-10 in the culture medium of splenocytes was increased. The content of IL- 2 was significantly decreased in HS500 group. In HS20, HS100, and HS500 groups, interferon (IFN)-g content was also significantly decreased.
By comparing GS and G groups, the presence of SDS evidently increased the efficiency of sensitization. In the case of patients sensitized to HWP1, detergents contained in facial soap might facilitate such sensitization.