[28], [29] It was also found that vascular endothelial cells can secrete VEGF to prevent cell apoptosis, and to protect cell basement membrane and cell plasticity. [30] In our study, we found that the serum VEGF concentration in serum and local BM microenvironment was lower in GvHD mice after MHC-haploidentical transplant, which is consistent with the reduced number of SECs in GvHD BM. Here, VEGFA is linked to graft versus host disease.