Open AccessTh2‐high asthma: a heterogeneous asthma population?
Author(s) -
Sven Seys,
Scheers Hans,
Marijsse Gudrun,
Dilissen Ellen,
Van Den Bergh Annelies,
Goeminne Pieter,
Van den Brande Paul,
Ceuppens Jan,
Dupont Lieven,
Bullens Dominique
Publication year - 2015
Publication title -
clinical and translational allergy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.979
H-Index - 37
ISSN - 2045-7022
DOI - 10.1186/2045-7022-5-s2-o1
Subject(s) - asthma , medicine , sputum , population , percentile , cluster (spacecraft) , airway , cytokine , immunology , pathology , surgery , statistics , tuberculosis , mathematics , environmental health , computer science , programming language
high patients had cytokine mRNA levels above the 90 th percentile value in controls. Unsupervised hierarchical clustering was used to determine unique cytokine-based patient clusters. Results Cubic Clustering Criterion, pseudo F and t 2 statistics revealed a two- and a six-cluster model. The first cluster (n=23) was found in both models and consists of patients who present with an “IL-5-high and IL-17F-high” profile. Patients with an “IL-4- or IL-13-high” profile did not cluster in one single group. In the six-cluster model, the “IL-17F-low” group was divided into 5 separate clusters: “IL-5-high” profile (n=7), “IFN-g-high” profile (n=15), “IL-6- and/or TNF-high” profile (n=15), “IL-22-high” profile (n=15) and those patients that were low for all preceding cytokines (n=130; cluster 6). “IL-17F- and IL-5-high” patients had significantly lower FEV1 and higher sputum neutrophils. Patients that were only “IL-4or IL-13-high” (cluster 6) had highest FENO levels and sputum eosinophils. Conclusion Th2-high asthma can be subdivided in patients with “IL-5-high and IL-17F-high” asthma and those with “IL4- or IL-13-high” asthma. The inflammatory pattern is different between both groups. The former group is characterized by mixed granulocytic airway inflammation whereas the latter group consists of patients with eosinophilic airway inflammation.