Relative IgE predominance within a core nsLTP panel may support clinical interpretation of multiplex sensitization profiles.

Background. Non-specific lipid transfer proteins (nsLTPs) are major plant panallergens in Mediterranean plant-food allergy. In multiplex diagnostics, Pru p 3 reactivity often coexists with pollen-associated nsLTPs, making clinical interpretation difficult. Methods. We analyzed consecutive patients tested with ALEX² between 2021 and 2025. Among 5044 patients, 1271 were reactive to at least one molecule of a predefined core-4 nsLTP panel: Pru p 3, Art v 3, Pla a 3 and Ole e 7. High-confidence predominant profiles were defined by target IgE ≥0.30 kUA/L, target contribution ≥50% of the total core-4 signal and molecule-specific log-ratio enrichment; the top 50 patients per molecule were selected. Food allergy and respiratory symptoms were analysed using adjusted logistic regression. Serum-pool inhibition experiments explored homologous and heterologous IgE inhibition. Results. The final sample included 200 patients equally distributed across the four predominant profiles. Pru p 3 predominance was associated with the highest frequency of food allergy, whereas Art v 3-, Pla a 3- and Ole e 7-predominant profiles showed greater respiratory involvement. In adjusted models, Art v 3- and Pla a 3-predominant profiles had lower odds of food allergy than Pru p 3 predominance, while all pollen-associated predominant profiles showed higher odds of respiratory symptoms. Inhibition experiments showed strong homologous inhibition and variable heterologous inhibition, supporting partially overlapping but non-identical IgE recognition patterns. Conclusions. Relative IgE predominance within a core-4 nsLTP panel may help contextualize complex multiplex profiles beyond the canonical Pru p 3-food allergy association, without assigning sensitization chronology.