FIGURE 1.

Initial screening of the HDF proteome. (a) Workflow of sample acquisition and preparation (blue) and bioinformatic analysis (green) followed in this study. Classification of different age groups and number of donors per group (table). (b) PLS analysis of age‐associated proteins from five age groups: 20–34, 35–49, 50–64, 65–79, and 80+ years old. (c) Volcano plot showing beta coefficients of proteins regressed with age (per year). Proteins showing significantly increased (red dots) or decreased (blue dots) levels with age (p < 0.05, adjusted for covariates). Gray dots show proteins that did not change significantly with age (p > 0.05). (d) Heatmaps of the top 20 significantly elevated proteins (left) and top 20 significantly reduced proteins (right) with age based on p‐adjusted values. (e) Heatmap of the levels of prominent proteins governing the expression of collagens (TGFB1 and SMAD4) and different collagens (COL1A1, COL1A2, COL5A3, COL6A1, and COL7A1) across the age groups