This is a pilot study to investigate the effect of TL01 narrow band UVB therapy on the resident dermal dendritic cells characterized by expression of CD1c and CD141. These cells were reported to have a role in induction of tolerogenic regulatory T cells and production of IL-10. The investigators proposed to investigate the effect of NB-UVB on these subsets of cells after two weeks of treatment to provide better understanding of the mechanism of action of light treatment.