Regulatory T-cells in Psoriasis Patients as Targets for Therapy

This is an observational study for the effect of different treatment options of psorisis on regulatory T-cells. Patients in whom a decision to treat with one of the following therapies (Dovobet, neotigason, narrow-band UVB and anti TNF alpha therapy) and agreed to take part in the study will be selected. Allocation of different treatments to patients is not part of the study. We will enroll 40 patients with moderate to severe psoriasis in the age range from 18 to 70. patients must be treatment-free for at least 2 weeks for topical application and 4 weeks for systemic treatment of psoriasis. females of child bearing potential must be on reliable contraception. Children below 18 years, patients above 70 years, pregnant and lactating patients and immunosuppressed patients are excluded from this study. Blood and tissue samples will be taken before and after treatment. We will also invite 10 patients who are receiving ellipse excisions of naevi, and who known not to have psoriasis, to provide control samples of distal skin beyond the margins required to demonstrate complete removal and control donation of blood.