Quantitative RT-PCR analysis of inflamed skin from Ahr−/− mice revealed statistically significant increased expression of growth factors and chemokines involved in neutrophil attraction (Csf2, Csf3, Cxcl1, Cxcl5) and of antimicrobial peptides typically present in psoriasis lesions (S100a7a, S100a8), as well as reduced expression of the keratinocyte differentiation marker Krt10 (Figure 2C). This evidence concerns the gene AHR and psoriasis.