Wheat-dependent exercise-induced anaphylaxis caused by percutaneous sensitisation to hydrolysed wheat protein in cosmetics

IgE and anaphylaxis specific to the carbohydrate alpha-gal depend on IL-4

BACKGROUND

Alpha-gal (Galα1-3Galβ1-4GlcNAc) is a carbohydrate with the potential to elicit fatal allergic reactions to mammalian meat and drugs of mammalian origin. This type of allergy is induced by tick bites, and therapeutic options for this skin-driven food allergy are limited to the avoidance of the allergen and treatment of symptoms. Thus, a better understanding of the immune mechanisms resulting in sensitization through the skin is crucial, especially in the case of a carbohydrate allergen for which underlying immune responses are poorly understood.

OBJECTIVE

We aimed to establish a mouse model of alpha-gal allergy for in-depth immunologic analyses.

METHODS

Alpha-galactosyltransferase 1-deficient mice devoid of alpha-gal glycosylations were sensitized with the alpha-gal-carrying self-protein mouse serum albumin by repetitive intracutaneous injections in combination with the adjuvant aluminum hydroxide. The role of basophils and IL-4 in sensitization was investigated by antibody-mediated depletion.

RESULTS

Alpha-gal-sensitized mice displayed increased levels of alpha-gal-specific IgE and IgG1 and developed systemic anaphylaxis on challenge with both alpha-gal-containing glycoproteins and glycolipids. In accordance with alpha-gal-allergic patients, we detected elevated numbers of basophils at the site of sensitization as well as increased numbers of alpha-gal-specific B cells, germinal center B cells, and B cells of IgE and IgG1 isotypes in skin-draining lymph nodes. By depleting IL-4 during sensitization, we demonstrated for the first time that sensitization and elicitation of allergy to alpha-gal and correspondingly to a carbohydrate allergen is dependent on IL-4.

CONCLUSION

These findings establish IL-4 as a potential target to interfere with alpha-gal allergy elicited by tick bites.

Wheat-dependent exercise-induced anaphylaxis: Subtypen, Diagnostik und Management

Die wheat‐dependent exercise‐induced anaphylaxis (Anstrengungs‐getriggerte Weizenallergie, WDEIA) ist eine IgE‐vermittelte Nahrungsmittelallergie, bei der es nur zu allergischen Symptomen kommt – welche von intermittierender Urtikaria bis hin zu schweren Anaphylaxien reichen können –, wenn Weizen im zeitlichen Zusammenhang mit verstärkenden Kofaktoren wie körperlicher Bewegung, nichtsteroidalen Antirheumatika oder Alkohol verzehrt wird. In den meisten Fällen weisen die Patienten eine Sensibilisierung auf ω5‐Gliadin in der Glutenfraktion des Weizens auf. ω5‐Gliadin‐negative Subtypen der WDEIA sind oft schwierig zu diagnostizieren und können durch Tri a 14 (Weizen‐Lipid‐Transferprotein), durch perkutane Sensibilisierung mit hydrolysierten Weizenproteinen oder, in seltenen Fällen, durch eine Gräserpollenkreuzreaktivität verursacht werden. Die Diagnose wird anhand der Anamnese in Kombination mit dem serologischen IgE‐Profil, Hauttests, Basophilenaktivierungstests und einer Provokationstestung mit Weizengluten und Kofaktoren gestellt. Die individuelle Ernährungsberatung ist nach wie vor die zentrale Säule im Management von Patienten mit WDEIA. Eine komplett weizenfreie Diät stellt eine mögliche Option dar, jedoch scheint diese die Toleranz weniger zu fördern als der weitergeführte regelmäßige Verzehr glutenhaltiger Getreidesorten, dieses allerdings nur bei gleichzeitiger Meidung von Kofaktoren. Alle Patienten sollten ein Notfallset zur Selbstbehandlung inklusive einem Adrenalin‐Autoinjektor erhalten und entsprechend geschult werden. Zur sublingualen Immuntherapie bei WDEIA, einer potenziell vielversprechenden therapeutischen Perspektive, werden weitere Daten benötigt. Dieser Artikel gibt einen Überblick über den aktuellen Wissensstand zur Diagnostik und zum Management bei WDEIA, einschließlich eines optimierten Provokationsprotokolls mit Weizengluten und Kofaktoren.

Wheat-dependent exercise-induced anaphylaxis: subtypes, diagnosis, and management

Wheat-dependent exercise-induced anaphylaxis (WDEIA) is an IgE-mediated food allergy with allergic symptoms ranging from intermittent urticaria to severe anaphylaxis that occurs when wheat ingestion is combined with augmenting cofactors such as exercise, non-steroidal anti-inflammatory drugs, or alcohol. In most cases, patients are identified by sensitization to ω5-gliadins in the gluten fraction of wheat. ω5-gliadin-negative subtypes of WDEIA are often difficult to diagnose and may be caused by Tri a 14 (wheat lipid transfer protein), after percutaneous sensitization with hydrolyzed wheat proteins, or, in rare cases, by cross-reactivity to grass pollen. Diagnosis is established based on the patients' history in combination with serum IgE profile, skin testing, basophil activation tests, and challenge tests with cofactors. Individual dietary counselling remains the central pillar in the management of WDEIA patients. A completely wheat-free diet is a possible option. However, this appears to promote tolerance less than continued regular consumption of gluten-containing cereals in the absence of cofactors. All patients should have an emergency set for self-treatment including an adrenaline autoinjector and receive adequate instruction. More data are needed on sublingual immunotherapy for WDEIA, a potentially promising therapeutic prospect. This article provides an overview of current knowledge on the diagnosis and management of WDEIA including an optimized challenge protocol using wheat gluten and cofactors.