Vascular gene delivery of anticoagulants by transplantation of retrovirally-transduced endothelial progenitor cells.
OBJECTIVE
Recent studies have documented the presence of bone marrow-derived endothelial progenitor cells (EPC) in the circulation of several species. This study was designed to evaluate the use of engineered EPC for vascular gene delivery into angioplasty-induced arterial lesions.


RESULTS
EPC could easily be isolated from whole bone marrow and peripheral blood of adult rats. Differentiation was induced by culture on fibronectin in the presence of endothelial specific growth factors. Rat EPC shared several phenotypic and functional properties with mature endothelial cells. Recombinant retroviruses were generated encoding for the anticoagulants tissue-type plasminogen activator (tPA) and hirudin. Efficient (>90%) ex vivo gene transfer could be achieved resulting in high levels of transgene production. Engineered EPC were locally infused into freshly balloon-injured carotid arteries. Analysis of day 7 vessels showed 73+/-10% luminal coverage of the lesioned arterial bed with transduced EPC. Sustained secretion of both anticoagulants could be detected in organ cultures of explanted arteries. EPC seeding inhibited dilation of the injured arterial segment and prevented reduction of media thickness. However, rapid repopulation with EPC failed to attenuate neointima formation in this model.


CONCLUSIONS
Peripheral blood and bone marrow can be used as source for endothelial lineage cells. Cultured EPC can be genetically engineered by retroviral gene transfer and serve as cellular vehicles for vascular gene and drug delivery of anticoagulants. Local transplantation of EPC attenuates reendothelialization of angioplasty-injured arteries but fails to inhibit neointima proliferation.
Griese
Daniel P
DP
Klinik und Poliklinik für Innere Medizin II, Universität Regensburg, Franz-Josef-Strauss-Allee 11, 93042, Regensburg, Germany. daniel.griese@klinik.uni-regensburg.de
Achatz
Stefan
S
Batzlsperger
Christian A
CA
Strauch
Ulrike G
UG
Grumbeck
Bernhard
B
Weil
Joachim
J
Riegger
Günter A J
GA
D000818:Animals; D000925:Anticoagulants / Q000008:administration & dosage; D001808:Blood Vessels; D020212:Carotid Artery Injuries / Q000601:surgery*; D002404:Catheterization / Q000009:adverse effects; D004730:Endothelium, Vascular / Q000473:pathology*; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000008:administration & dosage; D006629:Hirudins / Q000235:genetics; D008297:Male; D009389:Neovascularization, Pathologic; D051381:Rats; D017207:Rats, Sprague-Dawley; D012190:Retroviridae / Q000235:genetics; D033581:Stem Cell Transplantation / Q000379:methods*; D013234:Stem Cells / Q000378:metabolism / Q000821:virology; D010959:Tissue Plasminogen Activator / Q000235:genetics; D014161:Transduction, Genetic / Q000379:methods
D000925:Anticoagulants; D006629:Hirudins; D010959:Tissue Plasminogen Activator