Experimental sample groups and proteome clustering. (A) Schematic representations of the preclinical mouse models of ITP and their respective study groups, and the proposed parallelism with human ITP. (B) PCA of the platelet proteomes (postadjustment data) from both ITP models, at the thrombocytopenic and recovered normal platelet-count stage, and controls. (C) Cluster profile for each expression module, grouped by their common dynamics. Each gray line represents 1 protein, and the thick colored line represents the average for all. (D) Eigen protein heat map and dendrograms. Eigen proteins for each module are calculated by singular value decomposition and can be seen as linear combinations of the actual module proteins. (E) Heat map showing the correlation between modules and each of the groups (except the control), where red and blue represent high and low correlations, respectively. Each cell is composed of the correlation coefficient and, in brackets, the corresponding P value. A-ITP samples shared the same most significant modules, green and pink, but in opposite directions, pointing to a recovery of the phenotype via IVIg treatment. In addition, both ITP groups correlated with the black module, indicating a potential global ITP signature. Distinctively, the P-ITP D3 group correlated with the magenta and red modules, and to a lesser extent, with the brown module. Last, the P-ITP D7 group was associated only with the gray module, which comprises the set of proteins that have not been clustered in any module. SCID, severe combined immunodeficiency.