Related Experiment Video
Updated: Oct 5, 2026
A Component-resolved Diagnostic Approach for a Study on Grass Pollen Allergens in Chinese Southerners with Allergic Rhinitis and/or Asthma
Published on: June 4, 2017
Molecular sensitization clusters in adult atopy: an ALEX2-based analysis from Eastern Europe
Alexandra Chera1,2,3, Selda Ali1,2, Courtney Chau4
1Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
Background:
Allergen sensitization profiles vary geographically, yet Eastern Europe data remain scarce. This study aimed to identify and characterize molecular sensitization clusters in adults with allergic rhinitis (AR), asthma, and/or atopic dermatitis (AD) at a Romanian tertiary allergy center using ALEX2 multiplex profiling.
Methods:
Among 213 consecutive adults undergoing ALEX2 testing (January 2024-May 2026), 161 with confirmed AR, asthma, or AD formed the study population. Of these, 139 with at least one detectable allergen sensitization were included in Ward.D2 hierarchical clustering across 98 allergens. Associations were evaluated using Fisher's exact test with Benjamini-Hochberg correction.
Results:
The present study identified four primary molecular allergen sensitization clusters in an adult atopic cohort from Romania, with an exploratory, five-cluster refinement further resolving heterogeneity within the dominant cluster. 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.
Conclusion:
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.
