Antisense oligodeoxynucleotides prevent acute cardiac allograft rejection via a novel, nontoxic, highly efficient transfection method.
BACKGROUND
We hypothesized that ex vivo donor allograft transfection with antisense oligodeoxynucleotide (AS ODN) would inhibit the expression of intercellular adhesion molecule (ICAM)-1, an important mediator of T-cell adhesion and costimulation, and therefore suppress acute cardiac rejection.


METHODS
Hearts were transfected ex vivo with AS, reverse AS ODN, or saline by applying 3 atm pressure for 45 min at 4 degrees C. Grafts were then transplanted into allogenic recipients +/- treatment with leukocyte function-associated antigen (LFA)-1 monoclonal antibody (mAb) (1.5 mg/kg intravenously), cyclosporine (2.5 mg/ kg/day p.o.), or rapamycin (0.025 mg/kg/day intraperitoneally). Reperfusion injury was assessed in grafts harvested at early time points using the myeloperoxidase, %wet weight, and %contraction band necrosis assays; transfection efficiency was assessed using fluorescent microscopy; and efficacy of ICAM-1 blockade was assessed using immunohistochemistry. Other grafts were followed until rejection with donor/third-party skin grafting, adoptive transfer, and interleukin 2 infusion studies in selected recipients.


RESULTS
Transfection was highly efficient (fluorescein isothiocyanate-ODN in 48+/-5% of total myocardial nuclei), nontoxic, and reduced the ICAM-1-positive area to 53+/-14% versus having no effect on MHC class I expression (n=4). The incidence of survival >60 days after AS ODN + LFA-1 monoclonal antibody was 75%, significantly higher than other regimens.


CONCLUSIONS
AS ODN hyperbaric transfection proved highly efficient, effective at ICAM-1 blockade, and induced cardiac allograft tolerance when combined with LFA-1 monoclonal antibody. This highly targeted alteration of allograft immunogenicity may have an important role in future immunosuppressive strategies.
Poston
R S
RS
Department of Cardiothoracic Surgery, Stanford University School of Medicine, California 94305, USA.
Mann
M J
MJ
Hoyt
E G
EG
Ennen
M
M
Dzau
V J
VJ
Robbins
R C
RC
D000208:Acute Disease; D000818:Animals; D000911:Antibodies, Monoclonal / Q000502:physiology; D016572:Cyclosporine / Q000494:pharmacology; D015316:Genetic Therapy / Q000379:methods; D006084:Graft Rejection / Q000517:prevention & control*; D006085:Graft Survival / Q000187:drug effects; D016027:Heart Transplantation / Q000276:immunology*; D018799:Intercellular Adhesion Molecule-1 / Q000235:genetics / Q000502:physiology; D016169:Lymphocyte Function-Associated Antigen-1 / Q000276:immunology; D008297:Male; D020319:Oligodeoxyribonucleotides, Antisense / Q000627:therapeutic use*; D051381:Rats; D011912:Rats, Inbred ACI; D011914:Rats, Inbred BN; D017207:Rats, Sprague-Dawley; D013810:Therapeutic Equivalency; D014162:Transfection / Q000379:methods*; D014184:Transplantation, Homologous / Q000276:immunology
D000911:Antibodies, Monoclonal; D016169:Lymphocyte Function-Associated Antigen-1; D020319:Oligodeoxyribonucleotides, Antisense; D018799:Intercellular Adhesion Molecule-1; D016572:Cyclosporine