Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
Exp Eye Res. 2023 Nov;236:109657. doi: 10.1016/j.exer.2023.109657. Epub 2023 Sep 16.
Exposure to mustard agents, such as sulfur mustard (SM) and nitrogen mustard (NM), often results in ocular surface damage. This can lead to the emergence of various corneal disorders that are collectively referred to as mustard gas keratopathy (MGK). In this study, we aimed to develop a mouse model of MGK by using ocular NM exposure, and describe the subsequent structural changes analyzed across the different layers of the cornea. A 3 μL solution of 0.25 mg/mL or 5 mg/mL NM was applied to the center of the cornea via a 2-mm filter paper for 5 min. Mice were evaluated prior to and after exposure on days 1, 3, 7, 14, and 28 for 4 weeks using slit lamp examination with fluorescein staining. Anterior segment optical coherence tomography (AS-OCT) and in vivo confocal microscopy (IVCM) tracked changes in the epithelium, stroma, and endothelium of the cornea. Histologic evaluation was used to examine corneal cross-sections collected at the completion of follow-up. Following exposure, mice experienced central corneal epithelial erosion and thinning, accompanied by a decreased number of nerve branches in the subbasal plexus and increased activated keratocytes in the stroma in both dosages. The epithelium was recovered by day 3 in the low dose group, followed by exacerbated punctuate erosions alongside persistent corneal edema that arose and continued onward to four weeks post-exposure. The high dose group showed persistent epitheliopathy throughout the study. The endothelial cell density was reduced, more prominent in the high dose group, early after NM exposure, which persisted until the end of follow-up, along with increased polymegethism and pleomorphism. Microstructural changes in the central cornea at 4 weeks post-exposure included dysmorphic basal epithelial cells and reduced epithelial thickness, and in the limbal cornea included decreased cellular layers. We present a mouse model of MGK using NM that successfully replicates ocular injury caused by SM in humans who have been exposed to mustard gas.
芥子气暴露，如硫芥子气（SM）和氮芥子气（NM），常导致眼表损伤。这可能导致各种角膜疾病的出现，这些疾病统称为芥子气角膜病变（MGK）。在本研究中，我们旨在通过眼部 NM 暴露建立 MGK 小鼠模型，并描述随后分析角膜不同层结构变化。将 0.25mg/mL 或 5mg/mL NM 的 3μL 溶液通过 2mm 滤纸施加到角膜中央 5 分钟。在暴露前和暴露后第 1、3、7、14 和 28 天，通过裂隙灯检查用荧光素染色对小鼠进行评估，为期 4 周。前节光学相干断层扫描（AS-OCT）和体内共聚焦显微镜（IVCM）跟踪角膜上皮、基质和内皮的变化。组织学评估用于检查在随访结束时收集的角膜横截面。暴露后，小鼠经历中央角膜上皮侵蚀和变薄，伴随基质中基底丛神经分支减少和激活的角膜细胞增加。在低剂量组，第 3 天上皮恢复，随后出现加重的点状侵蚀，同时持续角膜水肿，持续到暴露后 4 周。高剂量组在整个研究中表现出持续的上皮病。内皮细胞密度降低，NM 暴露后早期更为明显，持续到随访结束，同时伴有多核和多形性增加。暴露后 4 周中央角膜的微观结构变化包括基底上皮细胞形态异常和上皮厚度减少，以及在角膜缘包括细胞层减少。我们使用 NM 建立了一种 MGK 小鼠模型，成功复制了暴露于芥子气的人类眼部损伤。
