North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA; Department of Pharmaceutical Sciences, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX, 76107, USA.
Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA.
Exp Eye Res. 2024 Nov;248:110100. doi: 10.1016/j.exer.2024.110100. Epub 2024 Sep 17.
Diabetes mellitus (DM) is a common metabolic disease associated with severe macrovascular and microvascular complications that influence nearly every tissue in the body, including the anterior and posterior segments of the eye. In the cornea, DM is associated with recurrent epithelial erosion and reduced wound-healing capacity, which increases the risk of corneal scarring. We previously developed a co-culture model of the cornea consisting of immortalized human corneal epithelial cells (hCE-TJ) overlaying a self-assembled stromal layer generated by human corneal fibroblasts (hCFs) over a 4-week period. In this study, we investigated epithelial-stromal constructs generated from hCFs derived from subjects with Type 1 (T1DM) or 2 diabetes (T2DM) compared to controls. We found that T2DM constructs exhibited a disrupted epithelium and a thicker, stratified stromal layer compared to controls or T1DM. Both T1DM and T2DM stromal constructs expressed lower expression of thrombospondin-1 in isolated extracellular vesicles (EVs) compared to controls with no significant difference observed in the presence of epithelial cells, suggesting that reduced provisional matrix secretion in the corneal stroma may be a factor that promotes delayed corneal wound healing in diabetes. The tetraspanins are established extracellular vesicle (EV) markers and include CD63, CD81, and CD9, and were highly expressed by EVs in all three cell types. Control corneal stromal fibroblasts produced more and larger EVs when compared to T1DM and T2DM hCF-derived EVs, supporting a role for altered cell-cell communication in the context of DM. Further characterization of EVs and their cargo is expected to aid in the development of targeted treatments to improve corneal wound healing.
糖尿病（DM）是一种常见的代谢疾病，与严重的大血管和微血管并发症有关，这些并发症影响身体几乎每一个组织，包括眼睛的前后段。在角膜中，DM 与复发性上皮糜烂和愈合能力降低有关，这增加了角膜瘢痕形成的风险。我们之前开发了一种角膜共培养模型，该模型由永生化的人角膜上皮细胞（hCE-TJ）覆盖在由人角膜成纤维细胞（hCF）产生的自组装基质层上，培养时间为 4 周。在这项研究中，我们研究了来自 1 型（T1DM）或 2 型糖尿病（T2DM）患者的 hCF 生成的上皮-基质构建体与对照相比。我们发现，与对照相比，T2DM 构建体表现出上皮破坏和更厚的分层基质层，而 T1DM 则没有。T1DM 和 T2DM 基质构建体在分离的细胞外囊泡（EV）中表达的血小板反应蛋白-1（TSP-1）较低，而在存在上皮细胞的情况下则没有明显差异，这表明角膜基质中临时基质分泌减少可能是促进糖尿病角膜愈合延迟的一个因素。四跨膜蛋白是成熟的细胞外囊泡（EV）标志物，包括 CD63、CD81 和 CD9，在所有三种细胞类型的 EV 中都高度表达。与 T1DM 和 T2DM hCF 衍生的 EV 相比，对照角膜基质成纤维细胞产生的 EV 更多且更大，这支持了 DM 背景下细胞间通讯改变的作用。对 EV 及其货物的进一步特征分析有望有助于开发针对改善角膜愈合的靶向治疗。
