PTGS2 and psoriasis: MutantGFP bulge HF‐SCs displayed a specific enrichment of genes encoding pro‐inflammatory mediators in psoriasis, in particular an increase in genes related to arachidonic acid (AA) metabolism, such as Ptgs2 (Figs 5B and EV4F), and specific pro‐inflammatory cytokines, such as Tnf‐α, Il‐23, and Il1‐α (Fig EV4G–I), whereas genes related to epithelial cell migration were down‐regulated (Fig EV4E).