IL1A and dermatitis: The application of phorbol 13-myristate 12-acetate (PMA) to mouse skin, a mouse model for acute skin inflammation, resulted in epidermal hyperplasia (increase in number of cells in an organ or tissue), leukocyte infiltration, increased Il1a mRNA production in keratinocytes and elevated levels of the acute-phase protein serum amyloid A (SAA) in WT mice.