Mesenehymal stem cells CMSCS are nonhematopoietie stromal cells that are capable of differentiating into, and contribute to the regeneration of, mesenchymal tissues such as bone, cartilage, muscle, ligament, tendon and adipose. MSCs have been isolated from human first- and second-trimester fetal blood, liver, spleen, bone marrow, adipose tissue, amniotie fluid, periosteum and embryo. Not only can they express many phynotypes involving adhesion molecules and chemokine receptors, but also have character of immune tolerance, so they have potential of migration and transportation to target issue and feature of immune suppressing. There are wide application prospects for a number of areas in the cardiovascular, neurological, blood, surgical injury and other diseases. The current review describes the phynotypes, the immune tolerance and the potential for homing of MSCs.

Generally speaking,the hepatocyte stem cell is not a specific cell type.but an overall name of all kinds of cells that possess stem cell characters about embryonic development and regeneration of liver.HSC is a pluripotential stem cells which have self-renewal capacity and could differentiate into mature hepatocytes and bile duct cells.According to the different origin of hepatocyte stem cell,it can be usually divided into two kinds:non liver-derived hepatocyte stem cell and liver-derived hepatocyte stem cell.

Objective To isolate and indentify fetal hepatic progenitor/stem cells, and study the feasibility and effectiveness of their transplantation on acute liver injury in nude mice. Methods The primitive cells isolated from 13.5dpc pregnant mouse fetal hver by way of enzyme digesting were cultured in vitro and liver specific markers as AFP, CK19, Albumin, c-Met, were identified by immunofluorescence and RT-PCR on colonies. 4 × 105 cells were transplanted into nude mice with carbon tetrachloride induced acute liver injury. Hapatic functions were measured pre- and -post transplantation on days 1,2,4, 7. Meanwhile, hepatic pathology was studied. Results Compared to control group the hepatic functions gradually recovered in transplant group, on days 1,2,4 after fetal hepatic stem cell transplantation. The hepatic pathology significantly improved in stem cells transplantation group. Conclution Fetal hepatic progenitor/stem cell were successfully yielded by enzyme digest. Stem cells transplantation improved the hepatic function and pathology in acute hapatic injury model of nude mice.