Kati Palosuo

A novel wheat gliadin as a cause of exercise-induced anaphylaxis.

BACKGROUND Food-dependent, exercise-induced anaphylaxis is a severe form of allergy; the reaction is caused by ingestion of a specific food before exercise. This disorder often escapes diagnosis because neither the ingested food nor the exercise alone induces the symptoms. OBJECTIVE The aim of the study was to characterize the allergens involved in wheat-dependent, exercise-induced anaphylaxis and to describe the clinical outcome in a series of 18 adult patients. METHODS All 18 patients had experienced recurrent episodes of generalized urticaria during exercise, 17 patients in association with collapse and 15 patients with an anaphylactic reaction. The symptoms appeared only when the patients had eaten food containing wheat before exercise. Wheat allergens were detected by immunoblotting, purified by gel filtration and reversed-phase chromatography, and subjected to N-terminal sequencing. The IgE-binding ability of the purified proteins was studied by ELISA, and their in vivo reactivity was studied by skin prick testing. RESULTS IgE antibodies from pooled patient sera were bound to 65-kd and 40-kd wheat proteins in immunoblotting. The 65-kd allergen was a previously undescribed wheat protein, showing 61% sequence identity to gamma-gliadin, whereas the 40-kd allergen had 100% identity to alpha-gliadin. In ELISA, all 18 patients showed elevated IgE levels to the novel gamma-like gliadin, and 13 of the patients showed elevated IgE levels to the alpha-gliadin. None of the 54 control subjects with wheat allergy, urticaria, or coeliac disease had IgE antibodies to the gamma-like gliadin. The in vivo reactivity of the gamma-like gliadin was verified by positive skin prick test responses in all of the 15 patients who were tested. During the follow-up on a gluten-free or wheat-free diet, 3 patients experienced reactions after having unknowingly eaten wheat before exercise, but all the other patients who were adhering to the diet remained symptom-free. CONCLUSION This study shows that wheat is a frequent cause of food-dependent, exercise-induced anaphylaxis and suggests that the major allergen is a previously undescribed gamma-like gliadin. For screening of this life-threatening allergy, we recommend skin prick testing with crude gliadin and we recommend a gluten-free diet for treatment.

Rye gamma-70 and gamma-35 secalins and barley gamma-3 hordein cross-react with omega-5 gliadin, a major allergen in wheat-dependent, exercise-induced anaphylaxis.

Patients with wheat‐dependent, exercise‐induced anaphylaxis experience severe allergic reactions when exercising after ingestion of wheat. The major wheat allergen associated with these reactions is a ω‐5 gliadin, and patients following a gluten‐free diet have remained free of symptoms.

Humoral and cellular responses to gliadin in wheat-dependent, exercise-induced anaphylaxis.

Background Wheat‐dependent, exercise‐induced anaphylaxis (WDEIA) is a severe allergy where wheat ingestion together with physical exercise induces anaphylaxis. We have previously shown that patients with WDEIA have IgE antibodies against gliadin proteins and identified ω‐5 gliadin (Tri a 19) as a major allergen.

Seasonal increase in human IgE and IgG4 antisaliva antibodies to Aedes mosquito bites.

BACKGROUND Mosquito bite-sensitive subjects frequently have circulating IgE and IgG4 antibodies to Aedes mosquito saliva proteins. METHODS In the present study we examined the antibody response during a mosquito season in 14 subjects living in Finnish Lapland. Immunoblotting was performed with Aedes communis saliva and the 22- and 36-kD antisaliva antibody bands were analyzed. RESULTS The preseason sera showed IgE antibodies to the main saliva antigens in 12, IgG4 antibodies in all 14 and IgG1 antibodies in 12 subjects, and the postseason sera in all but 1 subject. The postseason sera showed significantly more intense IgE (p < 0.05), IgG4 (p < 0.001) and IgG1 (p < 0.01) antibody bands than the preseason sera. CONCLUSION These results show that seasonal exposure to mosquito bites leads to an increased IgE, IgG4 and IgG1 antibody response, a phenomenon similar to that occurring e.g. in pollen allergy.

Gal d 1-specific IgE predicts allergy to heated egg in Finnish children

Allergen‐specific IgE levels can be useful in predicting outcomes of oral food challenges, but optimal cutoff levels vary in different populations. The aim was to determine cutoff values for egg white‐ and Gal d 1‐, Gal d 2‐, Gal d 3‐, and Gal d 4‐specific IgE (sIgE) predicting positive oral heated egg challenges in 185 Finnish children and adolescents.

The effect of oral immunotherapy treatment in severe IgE mediated milk, peanut, and egg allergy in adults: OIT in severe food allergy in adults

The standard care of severe food allergy in both adults and children means avoidance of allergens. In recent years promising results of oral immunotherapy (OIT) have been reported in children. In adults, information on OIT in severe food allergy is very limited.