Molecular and clinical characterization of nut, peanut, and seed allergies: the role of seed storage proteins

SUMMARY

Background. Seed Storage Proteins (SSPs) associate with severe allergic reactions to tree nuts, peanuts, and seeds. This study aimed to characterize the molecular and clinical profiles of SSP sensitization, in patients allergic to peanuts, tree nuts, and/or seeds and sensitized to 2S Albumins (2S) or 7S and 11S Globulins (7S and 11S, respectively). Methods. A retrospective analysis from 2016 to 2024 of the characteristics of peanuts, and/or seeds allergic patients who were sensitized to SSPs (identified by ImmunoCAP™ ISAC) was performed. Reaction severity was graded using the oFASS scale. Results. Sixty-six patients (median age 10 years, range 1–67, IQR 15) were included. Walnut caused 41% of the reactions, followed by hazelnut and peanut (21%). Sensitization rates were 88% for 2S (Jug r 1 48%, Ana o 3 29%), 36% for 11S (Cor a 9 29%), and 23% for 7S. Co-sensitization occurred within and across protein families (p < 0.05). Jug r 1, Cor a 14, Ana o 3, Ara h 1, 2, and 6 were clinically relevant for walnut, hazelnut, cashew, and peanut allergies (p < 0.05). Severe reactions correlated with co-sensitization to non‐specific lipid transfer proteins (nsLTPs) (p = 0.05). Conclusions. Jug r 1 (the main sensitizer), Cor a 9, Ana o 3, Ara h 1, 2, and 6 appear to be good markers of nut/peanut allergy. Co-sensitization to nsLTPs seems to exacerbate reaction severity. Identifying SSP sensitizations can improve diagnosis, management, and personalized recommendations for allergic patients.

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