Recipient intramuscular cotransfection of naked plasmid transforming growth factor β1 and interleukin 10 ameliorates lung graft ischemia-reperfusion injury

Objective: Multiple gene transfer might permit modulation of concurrent biochemical pathways involved in lung graft ischemia-reperfusion injury. In this study we analyzed whether recipient intramuscular naked plasmid cotransfection of transforming growth factor beta(1) and interleukin 10 would result in amelioration of lung graft ischemia-reperfusion injury. Methods: Forty-eight hours before transplantation, 6 groups (n = 6) of F344 rats received intramuscular injection of naked plasmid encoding chloramphenicol acetyltransferase, chloramphenicol acetyltransferase plus beta-galactosidase. transforming growth factor 0, interleukin 10, or transforming growth factor beta(1) plus interleukin 10 or were not treated, Donor lungs were flushed and stored for 18 hours at 4degreesC before transplantation. Twenty-four hours later, grafts were assessed immediately before the animals were killed. Arterial oxygenation, wet/dry ratio, myeloperoxidase, and proinflammatory cytokines (interleukin 1, tumor necrosis factor alpha, interferon gamma, and interleukin 2) were measured, and immunohistochemistry was performed. Results: For lung graft function, the arterial oxygenation was considerably higher in the cotransfected group receiving transforming growth factor beta(1) plus interleukin 10 compared with that in all other groups (P less than or equal to.03). The wet/dry ratio, reflecting lung edema, was reduced in the cotransfected group compared with that in control animals (nontreated, P <.02; chloramphenicol acetyltransferase, P <.03; chloramphenicol acetyltransferase plus beta-galactosidase, P <.01). Myeloperoxidase, which measures neutrophil sequestration, was also reduced with cotransfection compared with that seen in control animals (P ≤.03). All proinflammatory cytokines were decreased in the cotransfected group compared with those in all other groups (interleukin 1β P < 04: tumor necrosis factor alpha P < 002; interferon γ, P <.0001. interleukin 2, P <.03). These results indicate that cotransfection provides a synergistic benefit in graft function versus either cytokine alone, neutrophil sequestration, or inflammatory cytokine expression. Immunohistochemistry showed positive staining of transforming growth factor 01 plus interleukin 10 in type I and II pneumocytes and localized edema fluid. Conclusions: Recipient intramuscular naked plasmid cotransfection of transforming growth factor 0, and interleukin 10 provides a synergistic effect in ameliorating lung reperfusion injury after prolonged ischemia.