A pathogenetic approach to autoimmune skin disease therapy: psoriasis and biological drugs, unresolved issues, and future directions.

Psoriasis is a chronic inflammatory disease with a complex pathophysiology and a multigenic background. Autoimmunity and genetic hallmarks couple to confer the disease, which is characterized by chronic plaques (85-90% of all cases) and/or psoriasis arthritis (PsA), and involve the peripheral and sacro-iliac joints, nails, and skeleton. Dissecting the ethiopathogenetic mechanisms of psoriasis and PsA is a major basic research challenge.

Glucocorticoid-Induced TNFR family Related gene (GITR) enhances dendritic cell activity.

Glucocorticoid-Induced TNFR family Related gene (GITR), a Tumor Necrosis Factor Receptor Superfamily (TNFRSF) member involved in immune/inflammatory processes, has been previously shown to regulate T cell activation. To study GITR role in antigen presenting cells, we evaluated the capability of bone marrow derived dendritic cells (BMDC) from GITR(-/-) mice to stimulate the activation of CD4(+)CD25(-) T lymphocytes. We found that GITR(-/-) BMDC are weaker stimulators of T cell proliferation than GITR(+/+) BMDC, either in syngenic or allogenic BMDC/T cell co-cultures.

GILZ mediates the antiproliferative activity of glucocorticoids by negative regulation of Ras signaling.

Tsc22d3 coding for glucocorticoid-induced leucine zipper (GILZ) was initially identified as a dexamethasone-responsive gene involved in the control of T lymphocyte activation and apoptosis. However, the physiological role of this molecule and its function in the biological activity of glucocorticoids (GCs) has not been clarified. Here, we demonstrate that GILZ interacts directly with Ras in vitro and in vivo as shown by GILZ and Ras coimmunoprecipitation and colocalization upon PMA activation in primary mouse spleen T lymphocytes and thymus cells.