Transplantation of DBA/2 Mouse Corneas in BALB/c Recipients Signifi- cantly Delays Graft Rejection Compared with C3H Grafts and Facilitates Studies on Gene Transfer

To study the impact of gene transfer in experimental corneal transplantation, grafts should reliably be rejected but after a time span, which allows multiple interventions. We were interested in delaying transplant survival time through MHC-matching of donor and recipient animals and in omitting local dexamethasone treatment, which is laborious and could potentially interfere with the expression of administered DNA. Rejection of DBA/2 (H-2d) corneas by BALB/c (H2d) recipients occurred significantly delayed compared with C3H (H-2k) grafts (25.0 ± 5.6 vs. 14.5 ± 4.1 days, p=0.038), and correlated with the expression of allospecific T cell-proliferation and IFNsecretion in draining lymph nodes. Gene gun treatment with IL-4/CTLA-4 DNA MIDGE TM vectors in the lower lid of recipients significantly prolonged survival of DBA/2 corneas in BALB/c mice. This refined and dexamethasone-free protocol may be advantageous for the development of novel treatment strategies, e.g., local gene transfer, in corneal transplantation.