HEPATOCELLULAR TRANSPLANTATION AND TARGETING GENETIC MARKERS TO HEPATIC CELLS 
MOLONEY MURINE LEUKEMIA VIRUS 
Figure 1. Diagram of molecular clones to be used in this protocol and scheme for 
production of defective retroviral vectors. The parental retrovirus contains the gag, 
pol, and env genes, two LTR sequences and the ^ or packaging region. The schematic 
structures of mutants (N2 and LNL6) used for expression vectors, and the xj)' mutant 
used for creation of packaging cell line (PA317) are shown. The PA317 cell line produces 
only empty viral particles. When the N2 or LNL6 clones are introduced into this cell, 
infectious, defective retroviral vector is produced. 
The safety of the vectors which we propose to use in this study has been studied 
both in non-human primates (Kantoff et al, 1987; Cornetta et al, 1990). Monkeys have 
been infused with large quantities of the retroviral vector (viral stock constituting 
20% of the animal's blood volume). A transient adenopathy was noted which was thought 
to be due to the presence of fetal calf serum in the infusion, and this resolved within 
4-8 days. No complications of the vector infusion were found, and no evidence of 
infectious wild type or naturally recombinant virus was observed. This test was 
performed both on normal animals and animals pretreated with cyclosporin using a 
Recombinant DNA Research, Volume 14 
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