Evaluation of the effects of preconditioning regimens on hepatic veno-occlusive disease in mice after hematopoietic stem cell transplantation.

Pre-conditioning regimens before hematopoietic stem cell transplantation (HSCT), such as total body irradiation (TBI) or busulfan/cyclophosphamide (BU/CY), are associated with hepatic veno-occlusive disease (HVOD). However, the mechanism of these regimens on hepatic veno-occlusive disease remains unclear. The aim of this study is to evaluate the effect of TBI or BU/CY on HVOD in mice after HSCT. Mice received TBI or BU/CY followed by HSCT. Analysis of liver pathology and function, and platelet aggregation were performed. Both these regimens caused damage to liver sinusoid endothelial cells, leading to loss of normal structural integrity of liver sinusoid, abnormal liver function, fibrin deposition, inflammatory cells infiltration and platelet aggregation. No differences of liver function in these regimens were observed. Increased hepatic lipid droplets, mitochondrial swelling and higher incidence of HVOD were observed in BU/CY. In conclusion, both TBI and BU/CY caused damage to liver sinusoid endothelial cells and occurrence of HVOD with higher incidence for BU/CY. Meanwhile, inflammation and platelet activation was also observed, suggesting targeting them maybe beneficial in the prophylaxis of HVOD.