Transgene expression in a model of composite tissue allotransplantation.
BACKGROUND
Composite tissue allografting may be an ideal solution to many problems requiring reconstructive surgery. Unfortunately, complications associated with chronic immunocompromise are major impediments to widespread use of composite tissue allografting. Current immunosuppressive and immunomodulatory paradigms focus on modification of the recipient through global immunosuppression or donor/recipient chimerism. Alternatively, modifying the allograft to block rejection or promote tolerance could confine deleterious immunosuppressive effects to the graft or eliminate graft rejection. However, a technique introducing genetic information into the transplant is needed. The authors demonstrate the first model for expressing a gene of interest locally in a hind-limb transplant.


METHODS
Using a rat hind-limb transplant model, the authors tested the ability of naked DNA infusion, cationic polymer/DNA complex transfection, and adenoviral vector transduction to introduce genetic material into the composite tissue allograft. The marker genes luciferase and green fluorescent protein were used to follow gene expression.


RESULTS
Recombinant adenovirus showed rapid, high-level expression of marker genes in the graft, with no detectable expression in recipient animals. Expression was detectable at 18 hours and peaked at 7 days. Levels of expression were lower but above baseline at 4 weeks.


CONCLUSIONS
Using an adenoviral vector system, the authors have selectively introduced a marker gene (luciferase) into a transplanted hind-limb rat model. Expression was rapid and seen in a variety of cell types. Adenovirus infection had no impact on limb rejection. This method may be a powerful tool for genetically modifying composite tissue allografts and may contribute to immune tolerance and more widespread use of composite tissue allograft surgery.
Cooney
Damon S
DS
The Plastic Surgery Institute, Southern Illinois University School of Medicine, P.O. Box 19653, Springfield, IL 62794-9653, USA. dcooney@siumed.edu
Chambers
Christopher B
CB
Suchy
Hans
H
Hornick
M Christine
MC
Reichensperger
Joel
J
Neumeister
Michael W
MW
D000256:Adenoviridae / Q000276:immunology; D000818:Animals; D015870:Gene Expression; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D006614:Hindlimb / Q000637:transplantation*; D007108:Immune Tolerance / Q000276:immunology*; D007150:Immunohistochemistry; D008156:Luciferases; D008297:Male; D023421:Models, Animal; D051381:Rats; D011917:Rats, Inbred Lew; D011993:Recombinant Fusion Proteins / Q000276:immunology; D014162:Transfection; D019076:Transgenes / Q000235:genetics*; D014185:Transplantation, Isogeneic
D011993:Recombinant Fusion Proteins; D008156:Luciferases