Recombinant DNA Advisory Committee - 09/14-15/92 
Allergy and Infectious Diseases) differs from this proposal because it is only a clinical 
trial with no gene marking procedure and there is no fractionation of the T cells into 
CD4( + ) and CD8( + ) subpopulations. Therefore, it is relevant that the RAC review the 
entire protocol, not just the gene marking aspects. 
Following infusion, a select number of patients will have samples collected and their cells 
will be sorted for CD4( + ) and CD8( + ) cells. These cells will then be cultured to 
analyze virus production. Daily assays will be performed to monitor p24 antigen levels 
and viremia during the first week following infusion and weekly thereafter for six weeks. 
Any significant increase in HIV production will be detected immediately. 
Regarding cost to the individual patient participating in the protocol, Dr. Walker stated 
that NIH will assume all costs that are incurred after the screening visit. In the event of 
injury, the NIH will assume care for the patient to the extent that it is permitted. If a 
patient develops a chronic illness as a result of the therapeutic protocol, NIH would offer 
compensation and care on a case-by-case basis with the patient's home care provider. 
In response to concerns regarding competition for the identical twin population between 
researchers at different institutions, Dr. Walker explained that inevitably there will be 
competition for a limited pool of patients. The decision to participate is always made by 
the patient. Currently, there is no communication with other laboratories with regard to 
this issue. 
Presentation— Dr. Blaese 
Dr. Blaese addressed the issue of transduction efficiency. Transduction efficiencies 
observed in whole populations of cells is similar to those observed with CD4( + ) and 
CD8(+) subpopulations; however, there is variability between patients and between 
cultures. This result is the reason that latitude has been incorporated into the protocol 
regarding cell numbers. 
Discussion 
Dr. Parkman asked how they would distinguish the patient's autologous HIV infected 
cells from CD4( + ) and CD8( + ) that became infected following infusion? Will the 
patient's cells be selected in G418 in order to isolate and examine viral production in 
marked transduced cells? Dr. Blaese responded that these selection procedures would 
be performed. Dr. Parkman noted that this information was not included in the 
protocol. 
In response to Dr. Zallen's comments regarding the informed consent process for the 
healthy donor twin, Dr. Walker said that it is essential that the donor twin is aware of 
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