MTOR and graft versus host disease: Risk factors for the development of TA-TMA include specific conditioning regimens, calcineurin (CNI) and mammalian target of rapamycin inhibitors (mTORi), the presence of graft versus host disease (GVHD), venous thromboembolic disease, ABO incompatibility [36], human leukocyte antigen mismatch [3], and infection [5, 37–39].