In a human T cell-dependent peripheral blood mononuclear cell transplanted SCID (hu-SCID) model (52), treatment with CD83 antibody prevented GVHD in a dose-dependent manner and at the same time preserved the cytotoxic T-lymphocyte responses to viruses and malignant cells, which is superior to the current therapeutic manipulations which non-specifically target T cells. This evidence concerns the gene CD83 and graft versus host disease.