载药型晶状体囊袋张力环对猪眼晶状体囊袋内上皮细胞增殖的影响

Effect of drug-sustained capsular tension ring on proliferation of lens epithelial cells in vitro

目的研究载药型晶状体囊袋张力环对体外培养猪眼晶状体囊袋模型中晶状体上皮细胞增殖的影响，探讨载药型晶状体囊袋张力环防治后发性白内障的可能性。方法连续环形撕囊晶状体超声乳化吸除术制备猪眼晶状体囊袋模型，并随机分为CTR组：植入未经处理的晶状体囊袋张力环（n=13）；CTR—PLGA，biG132组：植入表面包裹PLGA—MG132的晶状体囊袋张力环（n=13）。晶状体囊袋模型体外培养3周，显微镜下方格计数法计算后囊膜细胞移行面积；晶状体囊袋模型行组织病理学检查；ELISA检测纤维连接蛋白表达量的差异。结果晶状体上皮细胞经2～3d生长潜伏期后，CTR组在（9．06±1．61）d完全覆盖后囊膜；随着培养时间的延长，后囊膜上细胞层次增加，囊膜皱褶增多；组织病理学检查可见薄层均质红染的后囊膜上被覆一层或多层排列紧密、核深染胞浆丰富的晶状体上皮细胞。而CTR-PLGA-MG132组，经4～5d生长潜伏期后，即可见晶状体上皮细胞点片状脱落，呈细小圆点状，仅残留少量细胞；1周后，细胞片状脱落、漂浮，后囊膜出现无细胞覆盖区；组织病理学检查可见均质红染的后囊膜上细胞排列松散，见无细胞覆盖区，前后囊膜平整光滑。ELISA检测CTR．PLGA．MG132组囊袋模型纤维连接蛋白表达量[（25．14±3．73）μg/ml]显著小于CTR组[（106．86±22．34）μg／m1]，差异有统计学意义（t=81．72，P〈0．01）。结论相比CTR组晶状体囊袋模型，CTR．PLGA．MG132组晶状体囊袋模型残留细胞在后囊膜上移行面积、纤维连接蛋白表达均明显减少。CTR—PLGA-MG132，可有效抑制猪眼晶状体囊袋模型中晶状体上皮细胞的增殖，减少上皮．问质转化。载药型晶状体囊袋张力环是白内障术后防治后发性白内障的一种创新性尝试。

Objective Our study was performed to design a drug-sustained capsular tension ring （CTR） to evaluate its potentiality on prevention of PCO in the swine capsular bag model in vitro. Methods Following the continuous capsule curvilinear capsulorhexis （CCCC）, Phacomulsification with capsular tension ring implantation was performed. CTR-supported swine capsular bag models were prepared and divided into two groups, group CTR （ n = 13 ） implanted with the original CTR without any modification and group CTR-PLGA-MG132 （ n = 13） implanted with the CTR covered with PLGA and MG132. The CTR- supported capsular bags were cultured in vitro for up to 3 weeks. The area of lens epithelial cells （ LEC ） coverage over the posterior capsule surface was quantified every day under microscope. The capsules were treated for histological examination . The change of fibroneetin was assessed by ELISA assay kit. Results After 2 - 3 days, outgrowth of LEC across the posterior capsule was observed, and the posterior capsule was totally covered by a confluent monolayer of cell after （9. 06 ± 1.61 ） days in group CTR. Capsular wrinkles became increasingly apparent as time progressed. An increase in capsular thickness was also observed. In contrast, there was less LEC deposition in group CTR-PLGA-MG132. Histological examination showed LEC layers were closely arranged on the posterior capsular surface in group CTR. In group CTR-PLGA-MG132, there was comparatively looser cell arrangement. Compared with group CTR, the mean fibronectin level of posterior capsule by week 3 in group CTR-PLGA-MG132 was 25.14μg/ml and 106. 09μg/ml respectively. Statistical analysis showed a significant difference （ P 〈 0.01 ）. Conclusions LEC migration, proliferation, and synthesis of EMT markers were inhibited in Group CTR-PLGA-MG132, compared with Group CTR. Drug-sustained capsular tension rings can effectively inhibit the migration, proliferation of LEC and the change of EMT （epithelial-to-mesenchymal transition） in swine capsular bag models. Drug-sustained capsular tension rings might be a potential therapy to prevent the posterior capsular opacification in the future.