Fig. 3
Proteins specifically expressed in papillary and reticular dermis are decreased in psoriasis lesions (skin anatomy atlas). Proteomic skin atlas data were used to identify proteins specifically expressed in basement membrane (BM) (a), papillary dermis (PD) (b), and reticular dermis (RD) (c). Left: Abundance of proteins is compared between compartments. Heatmaps show log10-transformed signed p values for the 12 proteins most specific to each compartment, where p values are derived from least-square regression models comparing abundance of proteins in each compartment to abundance in the other two (negative values indicate lower abundance; positive values indicate higher abundance). Middle: LC-MS/MS-estimated fold-changes (PP/PN) for each protein (n = 14 patients; yellow bars indicate DEPs). Average NSAF was calculated for PP and PN samples, respectively, and the higher of the two NSAF values is listed at the base of each bar. Right: Average fold change (PP/PN) was calculated for the 12 compartment-specific proteins (black arrow). This average value was compared with that obtained in 10,000 simulation trials in which 12 proteins were sampled randomly from 2194 proteins detected by LC-MS/MS. P values were calculated using the grey null distribution generated from the 10,000 simulation trials