Figure 4

Epidermal genes elevated in psoriasis lesions overlap best with genes induced by IL-1, IL-17, and IL-20 family cytokines in cultured KCs. In part (A), 709 epidermal PP-increased DEGs were evaluated to determine if they were disproportionately increased or decreased in each of 42 cytokine experiments. In each experiment, KCs or reconstituted epidermis was treated with cytokines and microarrays were used to identify induced genes. Experiments using HaCaT KCs are indicated with a single asterisk symbol (*), while experiments using 3-D reconstituted epidermis are indicated by a double asterisk (**). All other experiments utilized primary monolayer KC cultures. Labels list the cytokine used, the concentration (per mL), the length of time cells were treated, and the Gene Expression Omnibus accession under which raw data can be accessed. Positive statistics indicate that the 709 genes were disproportionately induced, while negative statistics indicate that the 709 genes were disproportionately repressed. A single asterisk symbol denotes significance according to the Wilcoxon rank sum test (FDR < 0.05), while two asterisk symbols denote significance according to both the Wilcoxon rank sum test and Fisher’s Exact Test (FDR < 0.05). In part (B), the analysis was repeated based upon 900 genes significantly elevated in LCM-dissected lesional epidermis as compared to LCM-dissected epidermis from uninvolved skin (FDR < 0.05 & FC > 1.50). In the bottom margin, red labels denote experiments with significantly positive statistics in both (A) and (B) (FDR < 0.05). Blue labels denote experiments with significantly negative statistics in both (A) and (B) (FDR < 0.05).