Fibrin polynucleotides are disclosed for preventing and/or treating graft versus host disease (GVHD) people, preferably in hematopoietic stem cell transplantation (IISCT), more preferable allogene hernatopoietic stein cell transplantations. Graft versus host disease(GVH disease) old man, which invents (GVHD), can be acute aGVHD and/or chronic cOVHD, preferably acute.