PROBLEM TO BE SOLVED: To provide an immunosuppressant represented by a graft-versus-host disease preventive/therapeutic agent.SOLUTION: An immunosuppressant comprises a caveolin 1 inhibitor as an active ingredient.SELECTED DRAWING: NoneCOPYRIGHT: (C)2016,JPO&INPIT【課題】移植片対宿主病予防治療剤に代表される免疫抑制剤の提供。【解決手段】カベオリン1阻害剤を有効成分とする免疫抑制剤。【選択図】なし