In a murine model system, it has been observed that the consumption of a Western diet (WD) high in fat and simple sugars dramatically increases the expression of PD-1 on γδ low (GDL) T cells, which are the main producers of IL-17A, thereby exacerbating the psoriasiform dermatitis induced by imiquimod (IMQ). This evidence concerns the gene PDCD1 and Psoriasiform dermatitis.