Reagents for Vector Production for Hematopoietic Gene TX

The goal of this research is to develop critical reagents that will support the production of highvector titers for transfusion medicine, ie. hematopoietic gene therapy for treatment of blood disordersas well as other applications. Attempts at concentrating these vectors has generally resulted in asignificant loss of infectious activity. One possibility is that the virus titer may be dependent upon thecomposition of the medium in which the viral producing cells (VPC) are grown; therefore, we will studydifferent media compositions in an effort to improve the vector titer produced by the VPC. A secondissue for the medium design is the safety and infusibility of the medium into human patients. The abilityto produce the vector supernatant in reagent medium would minimize the risk of immunizing the patientagainst foreign serum proteins in the media that might produce toxicities that could limit the usefulnessof the therapy. This would allow the direct injection of high titer virus and reduce the treatment timerequired for injected autologous VPC to produce the vectors. As a model system the PA3l7/LNL6packaging cell line that contains the LNL6 vector will be employed. The LNL6 vector carries the bacterialgene for neomycin resistance. Vector titer will be assessed using G418 resistant colony forming unitsby the G418 selection of infected NIH-3T3 fibroblasts. The regent medium will be developed with theeventual goal of producing a medium that is destined for direct infusibility into human patients.