fludarabine will be used for restoration of marrow 
function after intensive cytoxan and total body 
irradiation (DM90-106) . Multiple bone marrow 
aspirations from the iliac crests will be performed 
before cytoxan and TBI to store twice the engrafting 
dose of bone marrow (2 x 10 8 /kg nucleated cells) . A 
second bone marrow storage will be considered if less 
than 2 x 10 8 total nucleated cells/kg were collected 
in the first storage unless a back-up marrow is 
available. Another criterion for adequacy of the 
marrow collection will be a total of 2 x 10 4 CFUGM/kg . 
4 x 10 8 /kg nucleated cells and 2 x 10 4 CFUGM/kg from 
the peripheral blood will also be collected for 
reconstitution. Peripheral blood stem cells will be 
collected by continuous flow centrifuge during 
• hematopoietic recovery following daunomycin, and high 
dose ara-c or other chemotherapy of equivalent 
intensity . 
The peripheral blood and marrow will be subjected to 
CD3 4 positive selection. A total of 10.70 x 10 6 CD34 
positive cells/kg must be available. The retroviral 
marking will be performed as described in Appendix G 
and as follows: 
Thirty percent of the nucleated peripheral blood or 
marrow cells remaining after purging will be 
incubated with the LNL-6 or GIN vectors respectively 
at the time of storage before cryopreservation . For 
every nucleated peripheral blood or marrow cell 
obtained after Ficoll Hypaque separation, 10 vector 
particles (multiplicity of infection units) produced 
by Genetic Therapy, Inc. of Gaithersburg, Maryland, 
as an FDA approved product for this purpose, will be 
added to the nucleated cells and incubated as 
discussed in Appendix G. The final concentration of 
the cells in the vector incubation will be lxlO 6 
cells/cc. The cells will be rinsed and a small 
portion (10 6 ) cultured in a CFUGM assay and the 
majority of cells will be frozen and reinfused with 
the rest of the autologous marrow and peripheral 
blood cells. 
5.3 Treatment Plan: All patients should be treated in 
the Protected Environment if available. 
a. The preparative ablative regimen will consist of 
the following systemic chemotherapy: 
Cyclophosphamide (see Appendix C) : 60 mg/kg in 
0.5 liter D5W intravenously over 3 hours daily 
for 2 days - days 1 to 2 (total 120 mg/kg) ; 
mesna, 10 mg/kg will be given q4h during 
cyclophosphamide infusion and for 24 hours 
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