Recombinant DNA Advisory Committee - 10/7-8/91 
cell line or from the PA-1 cell line. If it is assumed that dying or dead cells are finding 
their way to the target tumor and are introducing a toxic metabolite of ganciclovir to 
these cells, there is the possibility that provirus from these cells will be introduced, i.e., 
secondary gene transfer process could occur in vivo. 
Dr. Freeman said he had not checked to see if provirus is transferred. Dr. Mclvor said 
that if a gene is being transferred into other tissues, the committee needs to be aware of 
that eventuality. This may create a safety problem if the gene is transferred into germ 
cells. 
Dr. McGarrity provided a clarification on the safety testing requirements. This is the 
first time that a continuous cell line has been used in a protocol submitted to the RAC. 
Previous protocols have involved ex vivo manipulations. The cells are removed from the 
patient, manipulated, and readministered to the patient. The committee has required 
helper cell lines to undergo a series of safety tests and evaluations. The same safety 
requirements apply to the continuous cell line that is to be used in this protocol. He 
stated that cell culture mycoplasma may induce interferon, activate macrophages, and 
induce IL-1, IL-2, or IL-6. This is the basis for safety concerns. 
Dr. Freeman said he plans to perform the necessary tests. He asked if the tests have to 
be done in advance or if he can provide a list of these tests. Dr. McGarrity asked if Dr. 
Freeman could rule out a mycoplasma effect on all the data presented. Dr. McCune 
replied that the PA-1 cells were checked for mycoplasma. 
Dr. Leventhal asked what tests the investigators propose to perform on the patients at 
the time of the second laparoscopy. Will the tests determine if any of the added 
material was transferred to the patient's tumor cells? If the treatment is failing, is it 
failing because the human ovarian tumor cells did not respond as expected in vivo, or 
because the ratio of the added cells to the resident tumor cells was ineffective? If there 
is a risk that the treatment will fail and the patients will die, there should be a provision 
that patients with gonads should be analyzed at post-mortem for the presence of the neo 
marker. Any other specific target tissues remaining should be assayed. 
Dr. Freeman said he is hoping the laparoscopy will be useful in determining the tumor 
burden. Performing a tumor biopsy to check the cells for vector DNA, as well as 
checking the germ line for transfer, is a good idea. It might not be ethical to require 
that in advance. He does plan to obtain tumor samples for analysis. Dr. Leventhal said 
it is reasonable to ask for a collection of peritoneal fluid at the time of the laparoscopy. 
She asked about the type of cell analysis. Dr. Freeman said he would look for the vector 
DNA; and if it works in an in vitro model, he will look for the enzyme or the ganciclovir 
phosphorylated compounds in the cells. 
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Recombinant DNA Research, Volume 15 
