Vascular Endothelial Growth Factor Receptor 1 (VEGFR1) Morpholino Increases Graft Survival in a Murine Penetrating Keratoplasty Model

Purpose: This study sought to determine whether a Vascular Endothelial Growth Factor Receptor 1 (VEGFR1)-specific morpholino could decrease neovascularization, thereby enhancing murine cornea transplant survival, and if this effect is synergistic with steroid therapy. Methods:Graft survival, corneal neovascularization, and corneal lymphangiogenesis were compared among the VEGFR1_MO, STD MO and PBS groups following subconjunctival injection in mice that underwent normal risk penetrating keratoplasty (NR PK) and high risk penetrating keratoplasty (HR PK). Graft survival, corneal neovascularization, and corneal lymphangiogenesis in groups treated with both VEGFR1_MO and steroid therapy were also analyzed in HR PK. Results:In NR PK, the VEGFR1_MO decreased angiogenesis, lymphangiogenesis, and increased graft survival compared to the PBS group (p=0.055, p=0.003, p=0.043, respectively). In HR PK, VEGFR1_MO decreased angiogenesis, lymphangiogenesis, and increased graft survival compared to the STD MO (p=0.000, p=0.000, p=0.029, respectively) and PBS groups (p=0.004, p=0.002, p=0.024). In HR PK, when the VEGFR1_MO was combined with steroid therapy, a significant increase in graft survival was seen in compared to steroid treatment alone (p=0.045). The two-month graft survival rate for HR PK was 27% in the combination group compared to 0% in the triamcinolone only group. Conclusions:VEGFR1_MO decreased angiogenesis and lymphangiogenesis, resulting in increased graft survival in both NR PK and HR PK. This beneficial effect is synergistically enhanced with steroid treatment in HR PK.