In a model of experimental graft-versus-host disease (GVHD) using murine allogeneic bone marrow transplantation (BMT), pretreatment of bone marrow-derived DCs with SAHA (a derivative of TSA) upregulated expression of the DC-suppressor, indoleamine 2,3-dioxygenase (IDO) leading to reduced GVHD [55]. The gene discussed is IDO1; the disease is graft versus host disease.