الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Stem cells have recently generated a great public and professional interest more than any other topic in biology. The ability of these cells to replace diseased or damaged cells provides cures for number of diseases were considered incurable by normal therapies. Potential sources of stem cells for therapy in liver injury include the embryonic stem cell, and cells from the bone marrow, umbilical cord blood, fetal liver, cirrhotic liver or even normal adult liver. Stem cells can be converted into new mature hepatocytes either by transdifferentiation or by fusion. Liver cirrhosis in humans represents the end stage of chronic liver injury. Liver transplantation provides a definitive cure for hepatocyte disease, obviously replacing all liver cells. But, transplantation comes with a requirement for lifelong immunosuppression, the limited availability of transplantable livers and considerable long-term side effects. The clinical trials investigating the effect of bone marrow stem cells BMSCs in patients with liver disease are mainly uncontrolled, with only small numbers of patients enrolled. Fetal liver cells display a great potential, but the experiments in this field are still in their infancy. The challenge in using ES cells as a viable source of liver stem cells lies in generating sufficient numbers of differentiated cells for transplant, as well as overcoming the ethical hurdles of objectors and the theoretical fear that a single undifferentiated ES cells transplanted into the body may eventually give rise to a teratoma. Hepatocyte transplantations have been performed for a variety of indications, including inborn errors of metabolism. Cells derived from other tissues, such as bone marrow, monocytes, endothelium, and pancreas, are also being explored as potential therapies for liver-based metabolic disorders. Stem cells are not only units of biological organization, responsible for the development and the regeneration of tissue and organ systems, but are also targets of carcinogenesis. Bone marrow stem cells can be used to accelerate liver regeneration before extended hepatectomy for hepatocellular carcinoma. However, despite the tremendous therapeutic promise of stem cells research, it has been met with heated opposition specially the human embryonic stem cells research. The harvesting of human embryonic stem cells involves the destruction of human embryo and, in its most controversial form (therapeutic cloning); it requires the creation of human embryo for the sole purpose of providing stem cells.