Improvement of mesenchymal stromal cells and their derivatives for treating acute liver failure.

After the death of large numbers of cells in liver tissue is triggered by various hepatotoxic factors, intimidating and life-threatening acute liver failure (ALF) can develop with high mortality and expensive costs. Although liver transplantation and hepatocyte transplantation have become substitutes for improving liver regeneration, their applications are inhibited by scarce tissue and cell resources. Therefore, the transplantation of mesenchymal stromal cells (MSCs) and their derivatives including hepatocyte-like cells (HLCs), conditioned medium (CM), and exosomes (Ex) can help alleviate liver injury in ALF individuals or animal models via engraftment into liver tissue, hepatogenic differentiation, the promotion of host hepatocyte proliferation, the secretion of anti-inflammatory factors and antioxidants, and the enhancement of liver regeneration in vivo. In addition, biomaterial scaffolds protect MSCs against a harsh microenvironment in vitro and in vivo, in addition to providing physical and directional support for liver regeneration. In this review, we aimed to discuss the underlying mechanisms and therapeutic effects of MSCs and their derivatives on rescuing ALF animal models according to current studies. Further breakthroughs are required to establish safer, more stable, and more effective stem cell-based therapy in regenerative medicine for repairing liver injury, thus reducing the morbidity and mortality of ALF in the near future.