Inhibition of nuclear factor kappaB by IkappaB superrepressor gene transfer ameliorates ischemia-reperfusion injury after experimental lung transplantation.
OBJECTIVE
Ischemia-reperfusion injury after lung transplantation is associated with significant morbidity and mortality. The activation of the transcription factor nuclear factor kappaB is central to the 2 important pathways that characterize ischemia-reperfusion injury, namely the inflammatory response and apoptosis. The purpose of this study was to determine the effects of nuclear factor kappaB inhibition on experimental lung transplant ischemia-reperfusion injury with gene transfer of the nuclear factor kappaB inhibitor IkappaB in a superrepressor form (IkappaBSR).


METHODS
An orthotopic left lung transplant model in isogeneic rats was used, with 18 hours of prolonged cold storage of donor lung grafts used to create severe ischemia-reperfusion injury. Donor rats underwent endobronchial gene transfection with saline alone or adenovirus encoding either beta-galactosidase control or IkappaBSR 48 hours before harvest. The function of transplanted lung grafts was assessed on the basis of isolated graft oxygenation, wet/dry lung weight ratio, and myeloperoxidase activity. Nuclear factor kappaB activation was assessed by means of enzyme-linked immunosorbent assay. Apoptotic cell death was assessed by evaluating the levels of histone-associated DNA fragments and caspase-3 activity.


RESULTS
Treatment of donor lung grafts with IkappaBSR resulted in significantly improved oxygenation compared with that seen in control tissue 24 hours after transplantation. IkappaBSR-treated lungs also demonstrated less pulmonary edema and reduced neutrophil infiltration 24 hours after reperfusion. Nuclear factor kappaB activation and apoptotic cell death induction 2 hours after transplantation was significantly reduced in IkappaBSR-treated lungs compared with in control lungs.


CONCLUSIONS
Inhibition of nuclear factor kappaB activation by IkappaBSR gene transfer improves transplanted lung graft oxygenation, decreases pulmonary edema and neutrophil sequestration, and reduces apoptotic cell death after experimental lung transplantation.
Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
Takaaki
T
Ishiyama
Sekhar
S
Dharmarajan
Makio
M
Hayama
Hisao
H
Moriya
Kathleen
K
Grapperhaus
G Alexander
GA
Patterson
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D020672:I-kappa B Proteins / Q000235:genetics* / Q000494:pharmacology; D016040:Lung Transplantation / Q000502:physiology; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000502:physiology; D011654:Pulmonary Edema / Q000517:prevention & control; D051381:Rats; D011916:Rats, Inbred F344; D015427:Reperfusion Injury / Q000503:physiopathology*; D014162:Transfection
D020672:I-kappa B Proteins; D016328:NF-kappa B; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases