TNF receptor secretion after ex vivo adenoviral gene transfer to cornea and effect on in vivo graft survival

PURPOSE. TO explore the potential for adenovirus-mediated ex vivo gene tran sfer of a soluble tumor necrosis factor (TNF) receptor and evaluate the eff ect of transplanting the adenovirally transplanted corneas in vivo. METHODS. Rabbit corneal segments were transfected with replication-deficien t adenovirus (AdTNFR) encoding a soluble TNF receptor fusion protein (TNFR- Ig). Production of TNFR-Ig was measured by using ELISA and bioassay. Cornea s were transfected ex vivo with AdTNFR and then transplanted in vivo. Survi val of AdTNFR-transfected corneas was compared with that of those treated e ither with a null vector control adenovirus (AdO) or nontransfected control corneas. RESULTS. EX vivo Production of a molecule with TNF blocking bioactivity fro m AdTNFR-transfected corneas was demonstrated over a period of 4 weeks. Tra nsplanted AdTNFR-transfected corneas showed a marginally increased survival time in vivo over nontransfected control corneas, but a significantly incr eased survival time over Ad0-treated control corneas. Ad0 treatment of corn eal allografts before transplantation had a proinflammatory effect and acce lerated the onset of corneal endothelial rejection. CONCLUSIONS. Adenoviral gene transfer is an effective means of transferring a gene encoding soluble TNFR-Ig to corneal endothelium, and ex vivo produc tion of a biologically active secreted molecule was demonstrated for 4 week s. However, in vivo, only a marginally increased survival was seen compared with control corneas. The introduction of this transgene using a less immu nogenic vector may demonstrate prolongation of corneal allograft survival.