Gene therapy of transplant arteriopathy by liposome-mediated transfection of endothelial nitric oxide synthase.
BACKGROUND
Transplant arteriopathy is the major factor limiting long-term survival after cardiac transplantation. We have previously demonstrated that liposome-mediated gene delivery of endothelial nitric oxide synthase (eNOS) to donor hearts reduces ischemia-reperfusion injury by blocking NFkappaB activation, adhesion molecule expression, and leukocyte infiltration. In this study, we used gene transfer of eNOS in a rabbit carotid transplant model to see whether these same effects would similarly ameliorate transplant arteriopathy.


METHODS
Liposomes complexed to the gene encoding eNOS were injected into donor carotid arterial segments that were transplanted orthotopically into recipient carotid arteries (n = 10). Controls included transplanted carotids transfected with liposomes complexed to empty plasmids (no functional gene) (n = 4) and transplanted carotids treated with saline (n = 6). Transplanted arteries were harvested for processing at 21 days. Intima/media (I/M) area ratios were calculated by computerized image analysis. Infiltrating T-lymphocytes and macrophages, and expression of VCAM-1 and ICAM-1 were quantified on immunocytochemistry.


RESULTS
The I/M ratio was significantly reduced in eNOS-transfected arteries compared with arteries transfected with empty plasmids and saline-treated controls. Compared to transplanted control arteries, eNOS-transfected arteries demonstrated significantly reduced T-cell infiltration into the intima and significantly reduced macrophage infiltration into the media. Cell surface expression of VCAM-1 and ICAM-1 were both reduced in eNOS-transfected arteries.


CONCLUSIONS
ENOS gene delivery can suppress neointimal lesion formation and T-lymphocyte and macrophage infiltration in transplanted arteries, associated with a reduction in relevant adhesion molecule expression. Thus, gene therapy with eNOS may not only reduce ischemia-reperfusion injury but may also ameliorate transplant arteriopathy in transplanted hearts.
Iwata
A
A
Division of Cardiothoracic Surgery, University of Washington, Seattle, Washington 98104, USA. aiwata@u.washington.edu
Sai
S
S
Moore
M
M
Nyhuis
J
J
de Fries-Hallstrand
R
R
Quetingco
G C
GC
Allen
M D
MD
D000818:Animals; D002339:Carotid Arteries / Q000187:drug effects / Q000473:pathology / Q000637:transplantation; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000201:enzymology* / Q000473:pathology; D015870:Gene Expression / Q000502:physiology; D015316:Genetic Therapy; D016027:Heart Transplantation; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D008081:Liposomes; D008264:Macrophages / Q000473:pathology; D015428:Myocardial Reperfusion Injury / Q000473:pathology / Q000628:therapy*; D019001:Nitric Oxide Synthase / Q000008:administration & dosage / Q000235:genetics*; D011817:Rabbits; D013601:T-Lymphocytes / Q000473:pathology; D014162:Transfection; D017539:Tunica Intima / Q000187:drug effects / Q000473:pathology; D017540:Tunica Media / Q000187:drug effects / Q000473:pathology; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
D008081:Liposomes; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D019001:Nitric Oxide Synthase