title: Prolongation of sheep corneal allograft survival by transfer of the gene encoding ovine IL-12-p40 but not IL-4 to donor corneal endothelium.
abstract: Immunological rejection is the major cause of human corneal allograft failure. We hypothesized that local production of IL-4 or the p40 subunit of IL-12 (p40 IL-12) by the grafted cornea might prolong allograft survival. Replication-deficient adenoviral vectors encoding ovine IL-4 or p40 IL-12 and GFP were generated and used to infect ovine corneas ex vivo. mRNA for each cytokine was detected in infected corneas, and the presence of secreted protein in corneal supernatants was confirmed by bioassay (for IL-4) or immunoprecipitation (for p40 IL-12). Sheep received uninfected or gene-modified orthotopic corneal allografts. Postoperatively, untreated corneas (n = 13) and corneas expressing GFP (n = 6) were rejected at a median of 21 and 20 days, respectively. Corneas expressing IL-4 (n = 6) underwent rejection at 18.5 days (p > 0.05 compared with controls) and histology demonstrated the presence of eosinophils. In contrast, corneas expressing p40 IL-12 (n = 9) showed prolonged allograft survival (median day to rejection = 45 days, p = 0.003). Local intraocular production of p40 IL-12 thus prolonged corneal graft survival significantly, but local production of the prototypic immunomodulatory cytokine IL-4 induced eosinophilia, inflammation, and rejection. These findings have important implications for the development of novel strategies to improve human corneal graft survival.
authors.affiliation: Department of Ophthalmology, Flinders University and Flinders Medical Centre, Adelaide, South Australia, Australia.
authors.forename: Sonja
authors.initials: S
authors.lastname: Klebe
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Coster
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Sykes
authors.forename: Sarah
authors.initials: S
authors.lastname: Swinburne
authors.forename: Peter
authors.initials: P
authors.lastname: Hallsworth
authors.forename: Jean-Pierre Y
authors.initials: JP
authors.lastname: Scheerlinck
authors.forename: Ravi
authors.initials: R
authors.lastname: Krishnan
authors.forename: Keryn A
authors.initials: KA
authors.lastname: Williams
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D002465:Cell Movement / Q000276:immunology; D002474:Cell-Free System / Q000276:immunology / Q000378:metabolism; D016039:Corneal Transplantation / Q000276:immunology* / Q000473:pathology; D004728:Endothelium, Corneal / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D006082:Graft Enhancement, Immunologic / Q000379:methods; D006085:Graft Survival / Q000235:genetics* / Q000276:immunology*; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D018664:Interleukin-12 / Q000008:administration & dosage / Q000096:biosynthesis / Q000235:genetics*; D053762:Interleukin-12 Subunit p40; D015847:Interleukin-4 / Q000096:biosynthesis / Q000235:genetics*; D007498:Iris / Q000276:immunology / Q000473:pathology; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000473:pathology; D009924:Organ Culture Techniques; D021122:Protein Subunits / Q000008:administration & dosage / Q000096:biosynthesis / Q000235:genetics*; D012756:Sheep; D014162:Transfection
chemical_list: D053762:Interleukin-12 Subunit p40; D021122:Protein Subunits; D049452:Green Fluorescent Proteins; D018664:Interleukin-12; D015847:Interleukin-4