to virus, the cells are harvested with trypsin and resuspended in normal saline containing 
heparin. In preparation for cell infusion the animal is anesthetized and taken to the fluoroscopy 
suite where a portal venogram is performed through the indwelling catheter to document the 
patency and placement of the catheter as well as the patency and integrity of the portal 
circulation. The cells are then infused into the catheter via the indwelling catheter in two 
aliquots (25 ml of cell suspension per aliquot each infused over 10 min). 
In our initial experiments we plan to leave the catheter in place following cell infusion 
and to flush it with a heparin containing solution approximately 2-3 times per week. The 
purpose of this is to determine the length of time that the catheter will stay patent and in the 
vessel. Approximately 2 weeks after cell infusion, the animal will be taken to the fluoroscopy 
suite where a portal venogram will be done to assess catheter placement and patency. A 
laporotomy will then be performed to identify any intra-abdominal pathology and to obtain a 
small amount of liver tissue for histological analysis. 
Table 2. Protocol For Preclinical Studies in the Baboon 
Time Event 
(-) Day 7 - Clinical evaluation to include blood 
chemistry/hematology 
Day 0 - Liver resection and catheter placement 
Tissue/blood saved for analysis 
- Hepatocytes isolated and plated in primary culture 
Day 2 - Viral supernatant placed on cultured hepatocytes 
Day 3 - Patency of catheter checked by portal venography 
- Hepatocytes isolated and infused into catheter 
- Cells and supernatants saved for analyses 
Day 1 0 - Blood obtained for analyses 
Day 13 - Patency of catheter checked by portal venography 
- Laparotomy to assess gross pathology and to obtain 
liver tissue for histology. 
c) Results of first baboon experiment 
We have completed our first baboon experiment with a second experiment planned for 
September or October. The first animal was a 17 kg juvenile male baboon (B206). A summary 
of the experimental results is provided in Table 3. The animal was taken to the operating room 
where the left lateral segment of the liver was resected without complication (See operative 
note). A Broviac catheter was placed in the inferior mesenteric vein as described above. The 
liver tissue, weighing 35 gm, was taken to the laboratory where it was perfused with 
collagenase to release hepatocytes. Approximately 0.7 x 10 9 cells were recovered with 98 % 
viability based on exclusion of trypan blue. The cells were plated onto 225 10 cm Primaria 
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