Fig. 4

a-b Hierarchical clustering control and COPD spot maps and principal component analysis. Twenty one differentially regulated proteins were identified with the Decyder 7.0 analysis software and used for hierarchical clustering in the extended data analysis (EDA) of the Decyder 7.0. Clustering of the differentially regulated protein expressed (red is up-regulated, green is down-regulated) revealed two groups of spot maps. Group 1 were mixed COPD and age-matched healthy control spot maps and Group 2 solely comprised COPD spot maps. The COPD spot maps in group 1 were designated as COPD group 1 and the COPD spot maps in group 2 were designated as COPD group 2 (a). The COPD group 1 spot maps in the Principal component analysis based on the 21 significant differentially regulated proteins were depicted in blue. Whereas the COPD group 2 spot maps were depicted in red and the age-matched controls were depicted in green (b)