(A) A volcano plot representation of all 1,317 proteins assayed in the aptamer-based screen; log-transformed data were used for analysis. In total, 112 proteins were significantly upregulated with an FC < 0.5 and P < 0.05. Of the 112 elevated proteins, 50 had a Spearman’s r > 0.6 with concurrent renal pathology CI (here, abbreviated CI). All these proteins had ROC AUC values of greater than 0.8, comparing patients with high CI with other patients with lupus. (B) A PCA plot of the 50 significantly elevated proteins in participants with high CI (FC > 2; P < 0.05; Spearman’s r > 0.6 with CI), with principal components (PCs) displayed on each axis. Concentration ellipses encompass each subject group, color coded as indicated. (C–E) The 50 proteins from the aptamer-based screen whose levels were elevated in individuals with high CI (FC > 2; P < 0.05; Spearman’s r > 0.6 with CI) were used for GO and KEGG pathway enrichment analysis. The implicated top 10 KEGG pathways (C), biological processes (D), and molecular functions (E) identified using the Database for Annotation, Visualization and Integrated Discovery are displayed. Annotation details are as listed in Figure 1. (F) The Cytoscape stringAPP was used to create protein-protein interaction networks for the significantly elevated proteins in individuals with high CI (FC > 2; P < 0.05; Spearman’s r > 0.6 with CI). Annotation details are as listed in Figure 1. Reactome pathways implicated include 2 dominant clusters: cluster 1, including formation of fibrin clot (clotting cascade) and hemostasis; and cluster 2, including complement cascade initial triggering of complement, and activation of C3 and C5.