Data Sheet 1_Molecular sensitization clusters in adult atopy: an ALEX2-based analysis from Eastern Europe.docx

Cluster 1 (pauci-sensitized, n=42) paradoxically showed a high asthma prevalence (54.8%) despite the lowest sensitization breadth (median 2 sensitizations) and total IgE (133.5 kU/L), though this finding did not reach significance in the global cluster comparison and should be considered exploratory. Cluster 2 (grass pollen-dominant, n=24) and Cluster 3 (polysensitized, n=47) showed near-universal AR prevalence. Cluster 4 (multi-panallergen PR-10/nsLTP, n=10) carried the highest rate of oral allergy syndrome (OAS) (30%), driven by PR-10 and nsLTP, whereas Cluster 5 (ragweed and profilin-dominant, n=16) showed exclusively profilin-mediated OAS.

Age was negatively correlated with sensitization breadth (Spearman r= -0.265, p=0.0016), with paradoxically elevated total IgE in older patients.</p>Conclusion<p>Unsupervised clustering of ALEX² data identified four primary molecular sensitization phenotypes in a Romanian adult atopic cohort, with an exploratory five-way refinement resolving additional clinically relevant heterogeneity, representing one of the first such characterizations from Eastern Europe.

Key clinical insights include a pauci-sensitized cluster with an exploratory enrichment for asthma and a region-specific ragweed/profilin cluster, highlighting the utility of multiplex molecular profiling in adult atopic disease.</p>