AIM: To investigate the expression and the significance of VEGF-C/D in rat cornea after alkali burning as well as the role of lymphangiogenesis in the high-risk corneal transplantation rejection.

METHODS: The model of alkali burn corneal was made. Different times corneas were taken to electron microscope for vascularization, and examined the expression of VEGF-C/D and VEGFR-3 in l, 3, 5, 7, 14, 28d. The other rat cornea after alkali burn were divided into four parts to penetrate keratoplasty, containing only blood vessels in the cornea(group A), angiogenesis and lymphangiogenesis(group B), lymphangiogenesis degenerating period(group C), angiogenesis degenerating period(group D). In addition, there are also normal groups(group N)to compare the RI values and survival time of corneal graft.

RESULTS: Electron microscopy showed that, when the first 7d rat cornea appeared neovascularization after alkali burn, but not lymphangiogenesis. The occurrence of new blood vessels and lymphatic in 2wk. There were no obvious lymphangiogenesis in 5wk and the angiogenesis gradually subside in 8 wk. The expression of VEGF-C/D and VEGFR-3 in the corneas of rats were up-regulated in the third days after the injury, and reached its peaks at 5d. The average survival time of group N, A, B, C, D were(14.25±0.62)d,(9.35±1.02)d,(5.06±1.13)d,(8.71±0.83)d,(9.44±1.05)d after transplant cornea. Compared to the rest of the group, group B plant average survival time significantly shortened(P<0.05), while compared with group B, the survival time of A, C, D groups were significantly longer(P<0.05).

CONCLUSION: VEGF - C/D and VEGFR-3 are expressed significantly after corneal alkali burn. New lymphatic vessels can accelerate high-risk corneal transplantation immune rejection.