Orthogonal projections to latent structures discriminant analysis (OPLS-DA) analysis of protein spot volumes of adipose tissue from controls and lean patients with chronic kidney disease (CKD). The presence or absence of CKD was used as the Y vector. The analysis was performed on 7 control individuals, 13 CKD patients, and 202 protein spots. The Hotelling T2 (based on 95% confidence level) tolerance ellipse is shown in the score plot (a), which shows all the individuals analyzed (controls yellow, CKD patients blue). Predictive loadings representing the analyzed protein spots are presented as a scatter plot for all protein spots (b) and as a column plot for spots that were identified and were significant in the model (c). In (b) and (c), vimentin_1 and α-1-microglobulin/bikunin precursor (AMBP) are marked in red. For protein name abbreviations, see legend to Figure 2. The significance of the differentially expressed spots was calculated as the difference between the absolute value of the loadings (ABS[loading]) and the absolute value of the corresponding jack-knife confidence interval (ABS[CI]). A positive difference indicates significance.