[Expression and function of ICOS on CD4 T cells and application to therapy in patients with ocular Behçet's disease with uveitis].

Uveitis in Behçet's disease (BD) is an important cause of vision loss through recurrent ocular inflammatory attacks. CD4 T cells that react to various self-antigens play a central role in the pathogenesis of this disease, and the activation or inactivation of the CD4 T cells is controlled by costimulatory molecules. In Behçet's disease patients with active uveitis, among the various costimulatory molecules, the inducible costimulator (ICOS), an active form of stimulatory molecule, is most strongly expressed, and is associated with cytokine production by Th1 and Th17 cells. It is suggested that ICOS could be a potential marker of disease activity and a candidate therapeutic target. Inhibition of the ICOS/B7RP-1 costimulatory pathway has demonstrated favorable therapeutic effects in various autoimmune diseases. Targeting the ICOS/ B7RP-1 costimulatory pathway may be a useful future treatment strategy for uveitis in Behçet's disease.