One could make the argument that our model of LIP-driven autoimmunity after transfer of PD-1−/− newly generated T cells to a lymphopenic host might actually be viewed as a model of syngeneic GVHD, similar to the autoimmunity that occurs when cyclosporine A (CsA) is discontinued post bone marrow transplantation. This evidence concerns the gene PDCD1 and Autoimmunity.