Methods: A clinical and laboratory study on ISAC in poly-sensitized allergic patients was concluded and three hundred and twenty-one subjects from 6 different Italian centers were evaluated. Patient’s history, skin prick tests, specific IgE using extractive allergens and ISAC were collected and evaluated. The results of all these measures were recorded on a electronic database and a “data-mining” approach based on a cluster analysis was performed using the free software PAST on ISAC results. First, a dendrogram based on was also employed using paired group as algorithm and Euclidean similarity measure. Then, the k-means clustering, a method of cluster analysis which aims to partition n observations into k clusters in which each observation belongs to the cluster with the nearest mean, was used starting from 2 to 10 different clusters.
Results: On the dendrogram, Parj2 and Phlp1/Phlp5/Cynd1 were completely separated from others, having an independent behavior. The Derp2/Derf2 and Betv1 were also independent clusters. Of note, also profilins, tropomyosins and polcalcins were identified as clusters, Lipid Transfer Proteins only partially, but the Betv1 family and serum-albumins were not because of the great heterogeneity of the observed results. K-clustering confirmed a similar trend: indeed, cluster analysis identified the principal association with great accuracy.
Conclusions: All these data confirm that major component families can be identified and shed a novel light on the close (or weak) relationships between cross reacting components and pan-allergens.