Co-signaling molecules in psoriasis pathogenesis: Implications for targeted therapy

Psoriasis is a T cell-dependent immune-mediated disease of the skin and joints. It is clear that co-stimulatory and co-inhibitory molecules (currently named co-signaling molecules collectively) synergize with TCR signaling to promote or inhibit T cell activation and function. In recent years, enthusiasm in the field of co-signaling research has been fueled by the success of co-stimulatory and co-inhibitory immunotherapy for the treatment of human diseases. This review outlines the involvement of several sets of co-signaling molecules in the immunopathogenesis of psoriasis. We then describe the relevant preclinical studies and summarize recent clinical findings on targeting these molecules for the treatment of psoriasis.