Progress in the understanding of
psoriasis as a T-cell mediated inflammatory disease has led to the development of new
immunomodulatory therapies. Currently the main focus is on the so-called biologics (or
biological agents), including fusion
proteins,
monoclonal antibodies,
cytokines and selective receptors. They mainly target single steps in the complex cascade of humoral and cellular inflammatory immuno-mechanisms that finally lead to the accelerated growth of epidermal and vascular cells in the psoriatic lesions. The most promising and advanced
biological agents are discussed along with their influence on the critical pathophysiological steps in
psoriasis, including depletion of T cells, blockade of initial T-cell activation and
T-cell receptor (TCR) stimulation, blockade of costimulatory signals and T-cell proliferative signals as well as restoration of the T helper type 1 (Th1)/Th2 balance by diminishing type 1
cytokines and administration of type 2
cytokines. In addition to the
biological agents, further development of 'classical' dermatological
therapies, such as
retinoids, or the discovery of new indications for non-
dermatological agents contribute to the novel pharmacological approaches in the treatment of
psoriasis.