Changing paradigms in dermatology: tumor necrosis factor alpha (TNF-alpha) blockade in psoriasis and psoriatic arthritis.

Psoriasis is an inflammatory T cell-mediated disease characterized by epidermal hyperplasia and parakeratosis, resulting in lesional areas of thick and scaling skin. Elevated levels of proinflammatory cytokines, including TNF-alpha, are found in psoriatic lesions. TNF-alpha has many effects in producing an inflammatory response such as stimulating production of pro-inflammatory molecules (eg, IL-1, IL-6, IL-8, NF-kappaB) and adhesion molecules (eg, ICAM-1, P-selectin, E-selectin). As such, TNF-alpha is a target for immunotherapy in the treatment of psoriasis and psoriatic arthritis. The role of TNF-alpha in the pathogenesis of psoriasis is reviewed, along with clinical trials demonstrating the efficacy of new anti-TNF-alpha immunobiologics in the treatment of psoriasis and psoriatic arthritis.