TGF-β1短期眼部应用对兔眼角膜碱烧伤后整合素β1表达的作用

目的：研究TGF—β1短期眼部应用对兔角膜碱烧伤后整合素β1表达和角膜上皮愈合的影响，探求其对角膜碱烧伤的治疗作用。方法：制备大耳自家兔角膜碱烧伤模型，一组给予TGF—β1（浓度为200ng／m1）局部滴眼，每日3次，连续7日；另一组给予PBS溶液代替，处理相同。于角膜碱烧伤后每13观察角膜上皮愈合面积，并于烧伤后6h、1d、3d、7d和14d5个时间点应用免疫组化方法检测TGF—β1实验组与PBS组角膜整合素β1表达情况。结果：烧伤后4d、10d、11d、12d和14d实验组和对照组上皮愈合率比较，差异有统计学意义（P〈0．05），两组随着上皮修复过程的进行，整合素B1的表达均逐渐增加，烧伤后7d、14d两个时间点实验组和对照组整合素B1平均灰度值比较，差异有显著性（P〈0．05）。结论：TGF—β1在活体实验中能促进整合素β1的表达，而后者的增加可以促进角膜上皮细胞向损伤区域的移行和粘附，从而减少碱烧伤愈合过程中上皮再次脱落现象，有利于创伤愈合。

Effect of TGF-beta1 on expression of integrin beta1 following corneal alkali burns in rabbits

PURPOSE: To observe the effect of TGF-beta1 applied topically to the alkali-injured rabbit eye on corneal epithelial wound healing and expression of integrin beta1 and its therapeutic action on corneal alkali burns. METHODS: Alkali burn was produced in 60 corneas from 30 rabbits. Two groups were randomly divided. One group was treated with TGF-beta1 solution (200 ng/ml) topically 3 times one day within the first 7 days, the other group was treated with phosphate-buffered saline (PBS) solution. The injured eyes were photographed after the fluorescence staining with a digital camera and the pictures were analyzed with computer-aided picture analysis system to calculate the rate of corneal epithelial healing. The expression of integrin beta1 was investigated in the point 6 h, 1 d, 3 d, 7 d, 14 d after the injury by means of immunohistochemical analysis. RESULTS: On the 4th, 10th, 11th, 12th and 14th days after the burning,the rate of corneal epithelial healing of TGF-beta1 groups was markedly higher than that of the PBS group (P < 0.05). The expression of integrin beta1 in the cornea epithelial cells gradually increased during the wound healing. On the 7th and 14th days after the burning, the expression of integrin beta1 in the cornea epithelial cells of TGF-beta1 group was remarkably higher than that of the PBS group (P < 0.05). CONCLUSIONS: TGF-beta1 could up-regulate integrin beta1 in vivo corneal alkali burn model, which could stimulate the cornea epithelial cells to migrate and adhere to the cornea stroma, that can reduce the cases of the epithelial cells'detachment from the cornea stroma and sustain the corneal reepithelization.