In this study, we evaluated the effect of placenta-derived Mesenchymal Stem Cells (MSCs) versus placebo in improving corneal transparency following experimental injury in an ex-vivo organ culture model of post-mortem human corneas. We also compared the influence of MSCs on the basic histopathology of the cornea and the immunohistochemistry markers of fibrotic corneal scarring. Mesenchymal Stem Cells extracted from the placenta were isolated and expanded in-vitro. Five pairs of post-mortem human corneas harvested for the corneal transplant of equal grade were included in the study. Corneas of the same pair were randomly assigned to either the case arm or the control arm. All corneas underwent a standardized superficial keratectomy, 4 mm in diameter. The case and control arm corneas received an intrastromal injection of MSCs and placebo respectively. The corneal button was maintained in an organ culture system for 28 days under the standard protocol. Laser light was passed through the corneas mounted on a self-styled modified artificial anterior chamber. Image analysis was used to quantify corneal transparency. Haematoxylin & Eosin staining and Immunohistochemistry was done for Alpha SMA (Smooth Muscle Actin). Laser scatter measurements were measured using Image Analysis (Image J Software). The difference in the mean of Full-Width Half Maximum (FWHM), Max intensity and Red pixel intensity between the cases and the controls was 101.5, 16.3 and 11.4 respectively which was found to be statistically significant (P < 0.05). Histopathology showed a disorganized Bowman's layer in the controls as compared to the cases. Alpha Smooth Muscle Actin at the injury site stained 3 + in all controls as compared to 1 + in the cases, showing a statistically significant difference (p = 0.005). Based on our findings, we consider that placenta-derived Mesenchymal Stem Cells can alter evolving corneal scarring into a more favourable outcome with better corneal transparency and lesser fibrotic corneal scarring.

中文翻译：

---

在离体器官培养模型中测试间充质干细胞在减少角膜瘢痕形成中功效的实验研究。

在这项研究中，我们评估了在人死后角膜的离体器官培养模型中，实验性损伤后胎盘来源的间充质干细胞（MSCs）与安慰剂相比在改善角膜透明性方面的作用。我们还比较了MSC对角膜基本组织病理学和纤维化角膜瘢痕形成的免疫组织化学标记的影响。从胎盘中提取的间充质干细胞被分离并体外扩增。该研究包括五对同等级别的角膜移植收获的验尸人角膜。同一对的角膜被随机分配到病例组或对照组。所有角膜均接受了直径4 mm的标准化浅表角膜切除术。病例和对照组角膜分别接受了基质干细胞间充质干细胞和安慰剂的注射。根据标准方案，将角膜纽扣在器官培养系统中维持28天。激光穿过安装在自称改良型人工前房上的角膜。图像分析用于量化角膜透明度。对αSMA（平滑肌肌动蛋白）进行了苏木精和曙红染色和免疫组化分析。使用图像分析（Image J软件）测量激光散射测量值。病例与对照组之间的半峰全宽（FWHM），最大强度和红色像素强度的平均值分别为101.5、16.3和11.4，具有统计学意义（P <0.05）。与病例相比，组织病理学显示对照中的鲍曼层混乱。在所有部位，受伤部位的α平滑肌肌动蛋白染色为3 +，而在所有情况下为1 +，显示出统计学上的显着差异（p = 0.005）。根据我们的发现，我们认为胎盘来源的间充质干细胞可以将发展的角膜瘢痕改变为更有利的结局，具有更好的角膜透明度和较少的纤维化角膜瘢痕。