Skip to main content
. 2024 Apr 29;83(9):1144–1155. doi: 10.1136/ard-2024-225596

Figure 2.

Figure 2

Proteomics-based discovery of autoantibodies in SSc. (A) Schematic illustration of the proteomics-based approach employed to identify autoantibodies associated with SSc. The graphic was generated using BioRender.com and complies with BioRender’s Academic License Terms. (B) Heatmap diagram displaying differentially expressed antibodies in the sera of patients with SSc compared with healthy controls. Red values indicate upregulation, while green values indicate downregulation. (C) Identification of autoantibodies by proteomics in SSc. Volcano plots illustrate iTRAQ proteomics results for enriched and purified proteins bound to antibodies in serum from patients with SSc versus healthy donors. The x-axis represents relative protein levels (mean log2 iTRAQ ratios across three replicate experiments) in patients with SSc compared with healthy donors, while the y-axis displays log10 (p values). Significantly enriched and upregulated proteins (p≤0.05; iTRAQ ratio ≥1.5) are denoted by red dots, significantly enriched and downregulated proteins (p≤0.05; iTRAQ ratio ≤−1.5) by blue dots, and all others by grey dots. The dotted lines indicate a 1.5-fold ratio (x-axis) and a p-value of 0.05 (y-axis). (D) Protein-protein interaction networks of a subset of significantly enriched and upregulated antibodies in SSc, highlighting PRMT5 as the antibody target. (E) Heatmap diagram depicting representative differentially expressed antibodies in SSc. Red values indicate upregulated proteins, while blue values indicate downregulated proteins. PRMT5 as the target is highlighted. iTRAQ, isobaric tags for relative and absolute quantitation; HC, healthy control; MS, mass spectrometry; SSc, systemic sclerosis.