孔源性视网膜脱离模型视网膜色素上皮细胞CD44的表达变化

The Expression of CD44 on Retinal Pigment Epithelial Cells Membrane in Rabbit Model of Rhegmatogenous Retinal Detachment

目的研究兔孔源性视网膜脱离模型视网膜色素上皮(retinal pigment epithelial,RPE)细胞CD44的表达,及其与孔源性视网膜脱离病理变化的关系。方法90只健康有色兔随机分为5组建立不同模型:Ⅰ组:孔源性视网膜脱离组,28只眼;Ⅱ组:孔源性视网膜脱离伴玻璃体积血组,27只眼;Ⅲ组:单纯视网膜裂孔组,18只眼;Ⅳ组:玻璃体切除组,17只眼;Ⅴ组:空白对照组,90只眼。分别于手术后不同时间点(1、3、7、14、21、28d)摘取各组兔眼眼球,用酶消化和机械分离法分离RPE细胞,制成细胞悬液,荧光免疫法标记CD44,用流式细胞仪检测各组RPE细胞膜上CD44的表达水平。结果Ⅰ组和Ⅱ组模型眼均发生视网膜脱离,Ⅲ组和Ⅳ组模型眼未发生视网膜脱离。Ⅰ、Ⅱ组中RPE细胞CD44的表达明显高于Ⅲ、Ⅳ、Ⅴ组,Ⅰ、Ⅱ组RPE细胞CD44表达水平在术后1d即增高,7d左右达到高峰,继而下降,Ⅰ、Ⅱ组与Ⅴ组RPE细胞CD44的表达差异有极显著性意义(均P<0.01),Ⅲ、Ⅳ组与Ⅴ组RPE细胞CD44表达差异无统计学意义(均P>0.05)。结论孔源性视网膜脱离中RPE细胞CD44表达增强,RPE细胞CD44的表达变化与孔源性视网膜脱离的病理发展关系密切。

Objective To study the characteristics of CD44 expression on retinal pigment epithelial（RPE） cells membrane in rabbit model of rhegmatogenous retinal detachment（RRD）. Methods Ninety adult pigmented rabbits were randomly divided into 5 groups： 28 in group Ⅰ（RRD model）, 27 in group Ⅱ （RRD with vitreous bleeding model）, 18 in groupⅢ （rhegmatoge nous retina model）, 17 in group IⅤ （vitrectomy model）. Only one eye per rabbit was used and the other eye was used for control, being as group Ⅴ （blank）. The eyes were removed at different time points（day 1, 3, 7, 14, 21 and 28） postoperatively. RPE cells were isolated by enzyme digest and mechanical methods, and were made into cell suspension. Flow cytometry was used to detect the expression level of CD44 on RPE cells membrane in each group. Analysis of variance was used for statistical analysis. Results Retinal detachment occurred in both groups I and Ⅱ but not in groups Ⅲ, Ⅳ and Ⅴ. The mean values of CD44 expressed on RPE cells membrane in groups Ⅰ and Ⅱ were higher than those in groups Ⅱ ,Ⅳ andⅤ. In groups Ⅰ and Ⅱ , the expression levels of CD44 were increased from day 1, reached its peak on day 7 and then decreased. As for CD44 expression, there was statistically significant difference between groups Ⅰ , Ⅱ and group Ⅴ （P〈0. 01）. No statistically significant difference was found between groups Ⅲ , Ⅳ and group Ⅴ （P〉0.05）. Conclusion The expression level of CD44 on RPE cells membrane is increased in RRD. The change of CD44 expressed on RPE cells membrane is correlated closely to the pathologic development of RRD.