Hierarchical cluster analysis of proteins expressed with statistically significant differences between patient subgroups. The inter-individual and inter-group variation in 19 selected proteins is represented in the form of a heatmap. The protein expression data were reordered by hierarchical cluster analysis (HCA) using Pearson centred correlation (unweighted pair group method with arithmetic mean (UPGMA)), which revealed specific expression patterns. Two main clusters of proteins are highlighted by the coloured bars (blue, red). Each patient sample is represented by a single numbered column (oligarticular 1 to 7 and polyarticular 9 to 15). Spot numbers and protein identifications (UniProt code) are labelled on the vertical axis; unidentified protein spots are indicated by an asterix (*). The relative amount of a protein is denoted by colour intensity within a spectrum of black to red, red being the highest amount.
Finnegan et al. Arthritis Research & Therapy 2014 16:R8 doi:10.1186/ar4434