The proteomic skin profile of moderate-to-severe atopic dermatitis patients shows an inflammatory signature

Moderate-to-severe atopic dermatitis (AD) is increasingly recognized as a systemic disease, largely due to proteomic blood studies. There are growing efforts to develop AD biomarkers using minimal tissues. To characterize the AD skin proteomic signature and its relationship with the blood proteome and genomic skin profile in the same individuals. We evaluated lesional and nonlesional biopsy samples and blood from 20 individuals with moderate-to-severe AD and 28 healthy individuals using Olink Proteomics (Uppsala, Sweden), using 10 μg/10 μL for skin and blood and RNA sequencing of the skin. The AD skin proteome demonstrated significant upregulation in lesional and even in nonlesional skin compared with controls in inflammatory markers (matrix metalloproteinase 12; T-helper cell [Th]2/interleukin [IL]-1 receptor-like 1[IL1RL1]/IL-33R, IL-13, chemokine [C-C motif] ligand [CCL] 17; Th1/C-X-C motif chemokine 10; Th17/Th22/PI3, CCL20, S100A12), and in cardiovascular-associated proteins (E-selectin, matrix metalloproteinases, platelet growth factor, myeloperoxidase, fatty acid binding protein 4, and vascular endothelial growth factor A; false discovery rate,