competent virus (S+/L-). 
c. The cells will be trypsinized, harvested into 50 ml conical tubes (Falcon), 
washed three times in normal saline and counted by trypan dye exclusion. 
d. An aliquot of cells will be cryopreserved for DNA studies. 
e. The final cell concentration will be adjusted to no greater than IxlO 8 . 
VI. Potential Hazards of the Implantation of GITKSVNa Producer Cell lines 
into Human Brain Tumors 
A. Potential suraicai complications. 
Infection: Patients with malignant brain tumors have a significant predisposition to a 
variety of superimposed infections secondary to a state of immune suppression as 
previously described. The probability of post operative wound infection is also 
increased due to previous radiation damage to the scalp following radiotherapy. 
Antibiotic therapy will be given as a prophylaxis prior to the surgical interventions and 
specific infections will be treated as needed. 
Increased ICP: Patients with an intracranial space occupying lesion often present 
with symptoms attributable to increased intracranial pressure (ICP). All the patients in 
this study will be treated prophylactically with high dose dexamethasone before the 
surgical procedures. Additional measures (Mannitol) will be given in the peri-operative 
period. 
Steroid complications: The long term effects of steroids are well documented. 
However, most of the patients who will enroll in our study will require steroids for 
control of increased ICP regardless of the proposed treatment. Inducing a reduction in 
tumor size may actually allow the reduction of the steroid dose in some patients. 
Chemical meningitis: Despite the lack of a meningeal reaction in our model 
laboratory animals, meningitis or meningitis-like symptoms may develop secondary to 
spillage of the vector-producer cells into the subarachnoid space. Such symptoms are 
expected to be self-limiting and ameliorated with symptomatic care (analgesics). 
However, such a reaction may be severe and could produce severe permanent 
neurological deficits or death. When indicated, CSF sampling may be required to rule 
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Recombinant DNA Research, Volume 15 
