| BACKGROUNDLiver cirrhosis (LC) is the major cause of morbidity and mortality in patients with chronichepatitis infection. Liver cirrhosis results from the formation and accumulation of fibrosiswhich lead to the development of progressive distortion of the hepatic architecture. Liverfibrosis is a reversible process and can revert with the removal of the underlying etiology,such as control of viral replication in chronic hepatitis B infection. LC is generallycharacterized by the excessive accumulation of extracellular matrix with the formation ofscar tissue that encapsulates the area of injury. Hepatic stellate cells activation is usuallyconsidered as the primary source of extracellular matrix in the liver after injury and is acritical event in the pathogenesis of liver fibrosis. LC usually progresses irreversibly into adecompensated stage that is characterized by a series of clinical manifestations, includingascites, variceal hemorrhage and hepatic encephalopathy; in particular, ascites is the mostcommon clinical symptom in such patients. Although ascites may be treated with diuretics,periodic paracentesis or with transjugular intrahepatic portosystemic shunt, only livertransplantation can improve the survival of these patients. However, the severe shortage ofdonor livers, high costs and serious potential complications have restricted the availabilityof liver transplantation worldwide. Therefore, alternative strategies, are under intenseinvestigation.Mesenchymal stem cells (MSCs), originating from the many mesenchymal andconnective tissues, has self-renewal abilities and multi-directional differentiation potentials.They also interact with various types of immune cells, leading to immunomodulation.Recently, MSCs have been used therapeutically in clinical trials forgraft-versus-host-disease following bone marrow transplantation, and appear to be effectivein regulating the immune response in settings such as tissue injury, transplantation andautoimmunity. In particular, MSCs has also been used to treat liver diseases in animalmodels and patients with liver diseases. Studies from animal models have shown that theinfusion of bone marrow-derived MSCs (BM-MSCs) ameliorates liver fibrosis and reversesfulminant hepatic failure. In clinical trials, autologous BM-MSCs infusion through the hepatic artery or portal vein has been demonstrated to be safe and feasible, and can improvethe liver function of some LC patients. However, in these studies the small size of thepatient cohorts and the lack of controls prevent firm conclusions being made with regard tothe safety and efficacy of this treatment in liver diseases. In addition, BM-MSCs frompatients with chronic HBV infection suffer from proliferative deficiency. Therefore, thetherapeutic use of autologous MSCs from patients with liver diseases may not be the bestchoice. In contrast, human umbilical cord-derived MSCs (UC-MSCs) are free from theselimitations related to autologous BM-MSCs. In addition, UC-MSCs can be obtained fromthe discarded umbilical cord and therefore can be produced on a large scale. It has beenreported that human UC-MSCs infusion can improve liver fibrosis in rats. Therefore,UC-MSCs have more potential to be used in clinical scenarios for the treatment of humanliver diseases.In our present study, we examine the safety and efficacy of UC-MSCs transfusion in38decompensated LC patients with ascites and compared to16matched controls whoreceived saline infusion.AIM1. To make a protocol of isolating and purifying the mesenchymal stem cells fromhuman umbilical cord, and to study their abilities to differentiate into hepatocyte invitro under the cytokine stimulations.2. To evaluate the safety and therapeutic efficacy of human UC-MSCs transfusion inpatients with decompensated liver cirrhosis.3. To investigate the effects of UC-MSCs on the activation and apoptosis of satellitecell line (LX-2) by coculture with UC-MSCs, and to elucidate the underlyingmechanisms of UC-MSCs treating decompensated LC.METHODS1. UC-MSCs were isolated and purified successfully based on the two steps digestion,and were further identified by morphology, surface markers and differentiation potential.2. UC-MSCs transfusions were performed in patients with decompensated livercirrhosis intravenously. The serum liver function markers such as ALB, TBIL, CHE, PA,and GLU, TC, UREA, AFP, WBC, AMY, CK-MB, as well as the hypogastric ascitesvolume and MELD scores were detected at different time points after treatment.3. LX-2were cocultured with UC-MSCs under different concentration, and the meanfluorescence intensity of α-SMA and the annexin V and7-AAD expression on LX-2cells were detected by FACS.RESULTS1. UC-MSCs expressed high levels of CD44, CD105CD73and CD90, butnegatively expressed CD34, CD45and HLA-DR. UC-MSCs have potentials todifferentiate into osteogenic, adpogenci and hepatic cells under various stimulatioins.2. The life qualities of most patients were improved after UC-MSCs transfusions.Except <38℃fever in4patients, no other side effects and oncogenecity were found. Nosignificant influences of UC-MSCs transfusion on GLU, TC, UREA, AFP, WBC, PA,AMY, CK-MB, ALT, TBIL, CHE and MELD scores were observed in the patients withdecompensated liver cirrhosis. We found that the ALB levels were significantly increasedand the hypogastric ascites volume were significantly reduced after36-week UC-MSCstransfusion as compared with saline controls in patients with decompensated livercirrhosis.3. UC-MSCs can inhibit the activation of LX-2and induce the apoptosis of LX-2independent on cell-to-cell contacts.CONCLUSION1. The isolated UC-MSCs displayed stem cell phenotypes and functions, and candifferentiate into hepatocyte-like cells in vitro.2. UC-MSCs transfusion intravenously displayed good safety and have a potential toimprove the ALB levels and reduce the hypogastric ascites volume in patients withdecompensated liver cirrhosis.3. UC-MSCs can significantly inhibit the activation of HSCs and inducing theirapoptosis independent on cell-to-cell contacts.4. UC-MSCs transfusion is clinically safe and could improve liver function andascites remission in decompensated LC patients with ascites. Therefore, UC-MSCstransfusion may present a novel therapeutic approach for the disease.
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