Lymphocyte Gene Therapy for Mild Hunter Syndrome 
For administration of cells to the patient, treated PBL will be harvested, washed, and 
resuspended in normal saline. The final cell preparation will be filtered through a platelet filter 
and transferred into a syringe or transfusion pack for infusion. 
The PBL preparation will be infused into a peripheral vein (or central venous catheter) over 
approximately 2 hours. A test dose of 2 - 5% of the total volume will be infused followed by an 
observation period of 5 - 10 minutes. The total volume of infused cells will not exceed 10 ml/kg of 
body weight per day and the infusion should usually be completed within 120 minutes. The cell 
suspension will be mixed gently approximately every 5 minutes during the infusion while the 
patient is being monitored for acute and subacute side effects. Antipyretics, antihistamines, 
narcotics, and/or anti-inflammatory agents will be administered to control symptoms associated 
with the infusion. Substantial or persistent symptoms or signs of toxicity may require 
discontinuation of the infusion. Once the optimal conditions for infusion have been identified, all 
subsequent infusions will be based upon this experience. The patient will be monitored for at 
least 2 hours after completion of each infusion prior to discharge. 
The cells will be administered in a dose-escalation format as described below. 
4.4.3. 1 First Infusion 
The initial infusion of L2SN-transduced autologous T-lymphocytes will be approximately 5 
x 10 7 cells representing 1% of the maximum feasible dose. 
4. 4.3. 2 Second Infusion 
The second infusion of transduced cells will be approximately 5 x 10 8 cells representing 
10% of the maximum feasible dose. 
4. 4.3. 3 Subsequent Infusions 
The third infusion, and all subsequent infusions, will be approximately 5 x 10 9 cells which 
constitutes the presumed maximum feasible dose of cells that can be harvested for treatment and 
re-infusion. 
4.4 Virus Production 
At this time, sufficient quantities of PA317-L2SN virus supernatant are readily produced in 
our research laboratory (Moos Tower Room 4-140, University of Minnesota, Minneapolis). 
However, clinical-grade retroviral-vector L2SN will be manufactured under conditions which 
meet U.S. Food and Drug Administration (FDA) requirements. The procedures used to 
manufacture clinical-grade L2SN will be approved by the FDA prior to use in this clinical trial. 
4.5 Schema And Duration Of Study 
4.5.1 Schema 
The overall treatment and evaluation plan for patients entering the study is detailed in 
Appendix A which also serves as a checklist for recording completion of specific procedures and 
completion of tests. The schedule for apheresis, culture and transduction of lymphocytes, and 
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