Human Gene Therapy Subcommittee - July 29-30, 1991 
approximately 50%. 
Dr. Rosenberg presented results showing his success in the establishment of cell lines 
from human cancers. The human tumor cells will be isolated from the patients, tissue 
culture lines will be started, the gene for TNF or IL-2 will be inserted, and the 
modified cells will be injected into the patients. After 21 days, the draining lymph 
node cells will be isolated. It has been much easier to transduce tumor cells than 
lymphocytes, in which expression of the gene is more difficult. The tumor cells 
transduce efficiently, express the genes, and secrete the proteins. 
Dr. Rosenberg reported nude mouse experiments in which the modified human 
melanoma cells did not grow. This result may seem astonishing because the effects of 
treatment are believed to be dependent on the immune system in syngeneic models. 
However, the nude mouse is not completely T cell deficient. Human tumors often do 
not grow in nude mice; the mice reject the cells as foreign. 
Based on the preclinical data in the mouse and in the human. Dr. Rosenberg said the 
proposed treatment schema is to use tumor cells that are resected as part of a standard 
treatment. The cell lines will be transduced with either the TNF or IL-2 genes and 
fi’ozen. Should the patient fail all other treatments and have widely metastatic disease, 
this clinical protocol will be offered. Should the patients become eligible, 2 x 10* gene- 
modified tumor cells will be injected subcutaneously into the right thigh, and then 2 x 
10^ intradermally at two nearby sites. After 21 days, the draining lymph node cells will 
be removed, grown in IL-2, and used for therapy. 
Dr. Rosenberg discussed the one unmet stipulation imposed by the NIH IBC. The IBC 
felt it would be important to treat several patients with tissue culture lines that were 
not gene-modified as a control for the introduction of gene-modified cells. This 
experiment would examine the toxicity of injecting tissue culture cells into patients. 
This treatment would not benefit the patient. It is very difficult to approach a patient 
and suggest administering unmodified tissue culture cells when data from the animal 
models predict that the gene-modified cells will be more potent. Dr. Rosenberg would 
prefer not to do this control experiment. 
Dr. Leventhal asked if the investigator could administer gene-modified cells in one 
thigh and unmodified cells in the other thigh to compare cells from the two different 
lymph nodes. This experiment would show if they are equally cytolytic against the 
target. Dr. Rosenberg replied that he could perform the different injections, biopsy the 
draining node on each side, and compare their in vitro activity. 
Dr. Carter said the IBCs rationale was based on a new approach in which live human 
tumor is excised, ex vivo, and administered to the patient. The IBC felt there were 
three possible risks in terms of safety: (1) the removal of tumor and returning it to the 
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Recombinant DNA Research, Volume 14 
