antigenic challenge when the patient was previously unresponsive, the development of normal 
lymphocyte counts in a previously lymphopenic patient, or the resolution of a chronic infection 
not being treated with specific antimicrobial therapy. 
10.2 Duration of the Study 
Part 1 of this protocol is expected to last 6-9 months. Part 2.A. is expected to require an 
additional 6-9 months. The duration of part 2.B. is dependent on the response of the individual 
patient but should last at least 6 months. Children who have demonstrated clear evidence of 
immunologic improvement will be maintained on periodic ADA gene-modified lymphocyte 
infusions indefinitely. 
11.0 Schema 
Part 1. 
Leukapheresis or phlebotomy to obtain peripheral blood lymphocytes. 
Induce lymphocyte proliferation in culture with anti-CD3 and IL2 
i 
Transduce proliferating lymphocytes with LASN vector 
>1 
Resuspend lymphocytes in fresh medium and grow for 2 to 7 days 
i 
Infuse approximately 80% of culture into patient. Analyze aliquot of 
the remaining cells as well as establish culture under selection for gene 
expression. Analyze and cryopreserve selected cells. 
Repeat procedure monthly for approximately 6 treatments 
i 
Comprehensive immunologic evaluation 
Part 2.A. i 
Repeat above procedure with infusions of selected cells. The selected cells can be 
prepared from fresh blood samples or previously characterized cryopreserved 
cells can be given, 
i 
Repeat infusions of selected cells for approximately 6 treatments 
Comprehensive immunologic evaluation 
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