We further determined the degree of keratinocyte proliferation as depicted by epidermal thickness, infiltration of lymphocytes and neutrophils, histopathologic scores of psoriasis (acanthosis, parakeratosis, hypogranulosis, and Munro's microabscess), and the expression of Keratin 17 (K17), a marker of keratinocyte hyperproliferation in psoriasis (Fig 2a-f) [3]. Here, KRT17 is linked to psoriasis.