Key Laboratory of Ophthalmology of the Ministry of Education and Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. htls2009 @ yahoo.cn
Ophthalmic Res. 2012;47(3):128-34. doi: 10.1159/000330271. Epub 2011 Oct 18.
Here we investigate the role of donor endothelium on allograft rejection in a lamellar keratoplasty (LK) model using grafts with or without donor endothelium.
Corneal buttons of donor C57BL/6 mice (2.0 mm) were transplanted to lamellar recipient beds (1.5 mm) in BALB/c mice. Two variations of the LK procedure were performed: (1) standard LK (SLK) (n = 13) without donor endothelium and (2) modified LK (MLK) (n = 14) with retained donor endothelium. The graft status was assessed by slit lamp biomicroscopy and scored for stromal opacity, corneal edema, neovascularization, and anterior chamber reaction up to 46 days post-transplantation. Corneas were also observed histologically.
The presence of a grafted corneal endothelium promoted graft rejection; 92.9% (13/14) of grafts were rejected in MLK after an average of 8.3 days, while 69.2% (9/13) of grafts were rejected in SLK on average 10.8 days after transplantation. The former's stromal opacity was significantly greater at all time points after day 14 except for day 21 (p = 0.77) and day 32 (p = 0.25). Corneal edema was significantly greater in the former at all time points after day 10 except for day 21 (p = 0.16). Neovascularization was significantly greater in the former at all time points after day 10 except for day 25 (p = 0.22).
Variations of this model of LK may be useful for studies of immunological mechanisms in corneal transplantation. The donor corneal endothelium may serve as a target of the immune response which promotes inflammation, neovascularization, and graft rejection.
本研究通过使用带有或不带有供体角膜内皮的移植物，在板层角膜移植（LK）模型中研究供体内皮在同种异体移植物排斥中的作用。
将供体 C57BL/6 小鼠（2.0mm）的角膜瓣移植到 BALB/c 小鼠的板层受体床（1.5mm）中。进行了两种变化的 LK 程序：（1）没有供体内皮的标准 LK（SLK）（n=13）和（2）保留供体内皮的改良 LK（MLK）（n=14）。通过裂隙灯生物显微镜评估移植物状态，并对基质混浊、角膜水肿、新生血管形成和移植后 46 天内的前房反应进行评分。还观察了角膜的组织学表现。
供体角膜内皮的存在促进了移植物排斥；在 MLK 中，92.9%（14/14）的移植物在平均 8.3 天后被排斥，而在 SLK 中，69.2%（13/13）的移植物在平均 10.8 天后被排斥。在前一种情况下，除第 21 天（p=0.77）和第 32 天（p=0.25）外，所有时间点的基质混浊均显著大于第 14 天以后的任何时间点。在前一种情况下，除第 21 天（p=0.16）外，所有时间点的角膜水肿均显著大于第 10 天以后的任何时间点。在前一种情况下，除第 25 天（p=0.22）外，所有时间点的新生血管均显著大于第 10 天以后的任何时间点。
这种 LK 模型的变化可能有助于研究角膜移植中的免疫机制。供体角膜内皮可能成为促进炎症、新生血管形成和移植物排斥的免疫反应的靶标。
