IL-20 appears to regulate the growth of keratinocytes during inflammation of the skin. It seems to be an autocrine factor for keratinocytes that regulates their participation in inflammation. Recombinant Human IL-20 produced in E. coli is a homodimeric, non-glycosylated polypeptide chain that is made up of 2 x 153 amino acids with a total molecular mass of 35.21 kDa.