Gene Transfer in Baboons Using Prosthetic Vascular Grafts Seeded with Retrovirally Transduced Smooth Muscle Cells: A Model for Local and Systemic Gene Therapy

Abstract

Prosthetic vascular grafts containing retrovirally transduced autologous vascular smooth muscle cells were studied as a model for introduction of human genes into baboons. Retroviral vectors encoding beta-galactosidase (beta-Gal) (LNPoZ) or human purine nucleoside phosphorylase (LPNSN-2), a control gene, were used for ex vivo transduction of autologous baboon smooth muscle cells obtained from vein biopsies. Transduced cells were placed into a collagen solution and seeded into the interstices of polytetrafluoroethylene vascular grafts. Endothelial cells were then seeded onto the luminal surface of the grafts to reduce thrombus formation. One LNPoZ-seeded graft and one LPNSN-2-seeded control graft were implanted bilaterally into the aorto-iliac circulation of each of 4 animals. All grafts remained patent until they were removed after 3-5 weeks and examined histochemically for vector-expressing cells. All histological cross-sections from the beta-Gal vector seeded grafts contained cells staining blue with the X-Gal chromogen. For the four grafts, the mean fraction of LNPoZ expressing cells was 10%, with a range of 2-20%, while no sections from the control grafts contained stainable cells. Smooth muscle cells expressing the reporter gene were localized within the graft wall but not in the newly forming intima or outer capsule of fibrous tissue. Implantation of transduced cells within this type of vascular graft may provide a useful approach for long-term local and systemic gene therapy.

Particle-mediated gene transfer with transforming growth factor-beta1 cDNAs enhances wound repair in rat skin.

“…Defects in wound healing could arise from growth factor, receptor, or signal transduction deficiencies. Strategies such as virally-mediated transfection (44)(45)(46)(47)(48) or the introduction of ex vivo transfected cells (45,(49)(50)(51)(52)(53) could certainly have a role in delivery of exogenous growth factors. Particle-mediated gene delivery is a simple and effective method of stimulating the autogenous, transient expression of molecules that improve the healing of wounds.…”

Granulocyte Colony-Stimulating Factor Expression from Transduced Vascular Smooth Muscle Cells Provides Sustained Neutrophil Increases in Rats

“…These cells were characterized by positive staining for muscle cell-specific actins with HHF35 antibody (Geary et al, 1994) while staining negative for von Willebrand factor (Geary et al, 1994), an endothelial cell-specific marker. Early-passage smooth muscle cells were exposed to 16-hr viras harvests from PA317-LrGSN and PA317-LASN amphotropic viras-producing cell lines for a period of 24 hr in the presence of Polybrene (4 figlml), and selected in G418 antibiotic (1 mg/ml).…”

Vascular Gene Transfer

“…6 Genetically engineered SMCs seeded in a vascular graft may be used for long-term local and systemic gene therapy. 7 Although SMCs could be used as a biological lining for endovascular stents, bypass grafts, and left ventricular assist devices, such a lining may be thrombogenic. Gene transfer of eNOS or cyclooxygenase-l to SMCs is a possible solution to this problem.…”