Involvement of the Programmed Death-1/Programmed Death-1 Ligand Pathway in CD4+CD25+ Regulatory T-Cell Activity to Suppress Alloimmune Responses

Abstract

The blockade of the PD-1/PD-L1 pathway abrogates Treg-mediated immunoregulation, thus suggesting that the PD-1/PD-L1 pathway is required for Treg suppression of the alloreactive responses of CD4+CD25-T cells. This finding has important implications for clarifying the mechanisms of allograft rejection and GvHD.