Biopsies from several normal and keloid scars were collected and the mRNA expression of several growth factors and cytokines were determined: transforming growth factor-β, fibroblast growth factor, IL-33, IL-22, arginase-1, arginase-2, inducible nitric oxide synthase, vasoactive intestinal peptide, and its receptor. The gene discussed is ARG2; the disease is keloid.