The following is a summary of the “High prevalence of lupin allergy among patients with peanut allergy: Identification of γ-conglutin as major allergen,” published in the February 2023 issue of Allergy and Clinical Immunology by Insunza, et al.

Examine the molecular underpinnings of lupin allergy (LA) and identify lupin allergens across three species that may have a role in cross-reactivity with peanut allergy (PA). Skin prick tests (SPTs) and specific immunoglobulin E (IgE) levels were used to assess food allergy in 43 people with PA, LA, or specific IgEs (sIgEs). Those sensitive to lupin were allowed to consume a lupin-containing item that could potentially trigger an oral food challenge (OFC). Sera from people allergic to lupin were tested using immunoblots and enzyme-linked immunosorbent assays.

In this investigation, LA was confirmed in 44% of the PA individuals using OFC. The most common reaction to consuming lupin was anaphylaxis; all it took to trigger it was 1 g of lupin flour. Both lupin-sensitized and confirmed LA participants had comparable lupin sIgE and SPT wheal sizes, and there was no difference in symptom severity between the two groups. In addition, individuals exposed to lupins had serum reactions to all three species. 

All of the sera tested showed immunoglobulin E binding to α- and γ-conglutin by immunoblotting and enzyme-linked immunosorbent tests, whereas recognition of α- and β-conglutin recognition varied. Based on the results, lupin should be listed as an allergen in food packaging because of the significant prevalence of LA among PA participants. The substantial variation in lupin-sIgE and lupin-SPT data suggests that OFC may be necessary for LA diagnosis. Lupin γ-conglutin is the primary allergen in the people.

Source: sciencedirect.com/science/article/abs/pii/S1081120622018191