Technical and Bioethical Challenges associated with using Stem Cells for Research and Therapy

Abstract

Millions of patients worldwide suffer from end-stage liver disease. Orthotopic liver transplantation has rapidly advanced and is currently the treatment of choice for patient with end-stage liver disease. However, the procedure requires major surgery, with many liver transplant recipients needing to spend time in intensive care units in the post-operative period, with considerable risks for infectious complications, acute renal failure and/or poorly functioning grafts (Razonable et al. 2011). Given the donor shortage and that only one or two patients at most may benefit from one donor liver, and the complexity associated with the transplantation procedure various alternatives have been evaluated, including cell therapies. The use of living cells as a therapeutic source to restore, maintain and/or enhance the liver function have numerous advantages when compared to organ transplantation as cells can be expanded in vitro to overcome the limits of organ shortage, cells can be genetically manipulated to correct functional and/or metabolic alterations, cells can be cryopreserved, transplanted without major surgical procedures and can be obtained from the same patients avoiding major risk of rejection and need for immunosuppressive treatments (Locke et al. 2009). Unfortunately adult hepatocytes cannot be expanded in vitro and cryopreserved cells are easily damaged during the freezing/thawing procedure.