 - Increased risk of transplant-related death. The use of anti-thymocyte globulin ATG has been demonstrated to modulate alloreactivity of T-lymphocytes, reducing the risk of post-transplant immune complications, namely graft rejection and GVHD. However, concerns about the use of ATG exist, in particular referring to an increased incidence and severity of infectious complications, increased risk of malignancy recurrence and increased risk of EBV-related PTLD. 