6.12 Patients will be treated with vinblastine alone for cycle 
1. Doses on successive cycles will be escalated by 10% 
to achieve a nadir ANC count < 1000/jil. Starting on 
cycle 2, patients will receive G-CSF 5jig/Kg SC daily 
starting on Day 6 and continuing until the ANC > 1500/jil 
on two successive determinations. A CBC with 
differential will be obtained two times per week. 
6.13 Patients will be treated with vinblastine until stable 
disease has been documented over 3 cycles or until 
progressive disease. 
7.0 Retroviral Transfection Procedure and Separation of CD34+ 
Population 
30% of the harvested bone marrow buffy coat cells will be used to 
separate the CD34+ stem cells and progenitors for gene transfer 
provided >1x108 buffy coat cells/Kg have been harvested. This 
separation will be done by immunoabsorption using the anti-CD34 
antibody 12.8 and the immunoabsorption column Separate SC in the 
Department of Transfusion Medicine, NIH. This method has been 
approved by the FDA for experimental use. The separated CD34+ 
cells will be co-cultured for 2-6 days with viral supernatant from 
the PA317 amphotrophic producer cell line in the presence of 
hematopoietic growth factors as well as protamine sulfate at 4 
jig/ml. Genetics Therapy, Inc. clinical grade viral supernatant will 
be sued for transduction. This supernatant will be prepared, tested 
and thawed as per IND #3042. This supernatant contains between 5 - 
20x1 0 5 MOI units per ml. The viral supernatant including the growth 
factors and protamine will be changed every 24 hours. 
After the period of in vitro culture, the cells are removed from the 
culture, pelleted, washed, and samples are taken for counting, 
hematologic and microbial cultures. The remaining cells will be 
frozen using standard procedures and stored in liquid nitrogen. 
After the frozen cells are thawed, they will be tested to determine 
the level of retroviral infection prior to reinfusion. If no bacterial 
or fungal contamination is found on gram stain and cultures, the 
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