HEPATOCELLULAR TRANSPLANTATION AND TARGETING GENETIC MARKERS TO HEPATIC CELLS 
surgical options, for whom the experimental protocol has a clear therapeutic intent, and 
for whom the added risk of gene transfer (which is not therapeutic) is commensurate with 
the severity of their underlying disease and its therapy; ii) obtaining informed consent 
describing both HCT and gene transfer; and iii) establishing institutional precedents 
for careful management and safety testing associated with gene transfer protocols; and 
iv) providing adequate follow-up and surveillance for any potential complications of 
either transplantation or gene transfer. 
The use of recombinant marker genes obviously raises distinct regulatory, safety, 
and ethical issues. We believe that the use of marker genes is safe and likely to yield 
information of value to the evaluation and implementation of HCT. We expect that the 
use of marker genes will enhance the probability that these initial clinical trials 
will produce verifiable data about the efficacy of HCT in human subjects. The use of 
marker genes may also benefit certain study subjects by providing information about the 
need for continued immunosuppression after heterologous HCT. These experiments also 
represent an important opportunity to assess the utility of methods for hepatic gene 
transfer which may be applicable for hepatic gene therapy in the future. 
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