Cardiac allograft tolerance induced by intra-arterial infusion of recombinant adenoviral CTLA4Ig.
BACKGROUND
Systemic administration of soluble recombinant fusion protein of cytotoxic T lymphocyte antigen 4 (CTLA4Ig) induces blockade of the CD28/B7 costimulatory pathway and promotes survival of allogeneic and xenogeneic grafts. We tested the efficacy of local expression of CTLA4Ig gene in the myocardium, induced by transduction with a recombinant adenovirus encoding the CTLA4Ig gene, on the survival of rat cardiac allografts.


METHODS
The donor hearts were perfused ex vivo with recombinant adenovirus encoding CTLA4Ig cDNA (AdCTLA4Ig) via intra-aorta coronary artery before transplantation. The distribution and duration of CTLA4Ig transgene expression in the myocardium was assessed by reverse transcriptase polymerase chain reaction (RT-PCR) or in situ RT-PCR after transplantation.


RESULTS
In situ RT-PCR demonstrated abundant expression of CTLA4Ig transgene in the endo-myocardium of AdCTLA4Ig-perfused cardiac grafts. Lewis and Brown Norway cardiac allografts transduced with AdCTLA4Ig survived indefinitely in nonimmunosuppressed Wistar Furth recipients. However, donor-strain skin grafts were rejected by long-term recipients of cardiac allografts, which also triggered the rejection of the primary heart grafts.


CONCLUSIONS
A single ex vivo intra-aortic infusion of recombinant adenovirus encoding the CTLA4Ig gene induced efficient transduction of the endo-myocardium and promoted the permanent survival of cardiac allografts in nonimmunosuppressed hosts. Despite the beneficial effect of local immunosuppression on cardiac allograft survival, the strategy failed to promote a state of donor-specific peripheral tolerance.
Yang
Z
Z
Department of Surgery, University of Pennsylvania Medical Center, Philadelphia 19104-4283, USA.
Rostami
S
S
Koeberlein
B
B
Barker
C F
CF
Naji
A
A
D000069594:Abatacept; D000256:Adenoviridae / Q000737:chemistry / Q000235:genetics; D000818:Animals; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000008:administration & dosage* / Q000235:genetics; D001011:Aorta; D060908:CTLA-4 Antigen; D005069:Evaluation Studies as Topic; D015870:Gene Expression; D018014:Gene Transfer Techniques; D006085:Graft Survival / Q000187:drug effects; D016027:Heart Transplantation / Q000276:immunology*; D007108:Immune Tolerance / Q000235:genetics; D018796:Immunoconjugates; D007141:Immunoglobulin Fc Fragments / Q000008:administration & dosage; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D007261:Infusions, Intra-Arterial; D007763:Lac Operon / Q000235:genetics; D051381:Rats; D011914:Rats, Inbred BN; D011917:Rats, Inbred Lew; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage*
D015703:Antigens, CD; D000943:Antigens, Differentiation; D060908:CTLA-4 Antigen; C556708:Ctla4 protein, rat; D018796:Immunoconjugates; D007141:Immunoglobulin Fc Fragments; D007166:Immunosuppressive Agents; D011993:Recombinant Fusion Proteins; D000069594:Abatacept