Our results suggested that Dara may induce Th17 (IFNγ˗IL17A+CD4+), Th1/17 (IFNγ+IL17A+CD4+), Tc17 (IFNγ˗IL17A+CD8+) and Tc1/17 (IFNγ+IL17A+CD8+) proliferation by the induction of increased IL17 mRNA expression in T cells in the xeno-GVHD model. This evidence concerns the gene CD4 and graft versus host disease.