Laboratory of Ocular Regenerative Medicine and Immunology, Biomedical Research Institute, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea.
Department of Ophthalmology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea.
Int J Mol Sci. 2023 Feb 7;24(4):3329. doi: 10.3390/ijms24043329.
Recent evidence shows that epithelial stem/progenitor cells in barrier tissues such as the skin, airways and intestines retain a memory of previous injuries, which enables tissues to accelerate barrier restoration after subsequent injuries. The corneal epithelium, the outermost layer of the cornea, is the frontline barrier for the eye and is maintained by epithelial stem/progenitor cells in the limbus. Herein, we provide evidence that inflammatory memory also exists in the cornea. In mice, eyes that had been exposed to corneal epithelial injury exhibited faster re-epithelialization of the cornea and lower levels of inflammatory cytokines following subsequent injury (either the same or a different type of injury) relative to naïve eyes without previous injury. In ocular Sjögren's syndrome patients, corneal punctate epithelial erosions were significantly reduced after experiencing infectious injury compared with before. These results demonstrate that previous exposure of the corneal epithelium to inflammatory stimuli enhances corneal wound healing in response to a secondary assault, a phenomenon which points to the presence of nonspecific inflammatory memory in the cornea.
最近的证据表明，皮肤、气道和肠道等屏障组织中的上皮干细胞/祖细胞保留了对先前损伤的记忆，这使组织能够在随后的损伤后加速屏障修复。角膜上皮是角膜的最外层，是眼睛的第一道屏障，由角膜缘的上皮干细胞/祖细胞维持。在此，我们提供证据表明，角膜中也存在炎症记忆。在小鼠中，与未受伤的眼睛相比，先前暴露于角膜上皮损伤的眼睛在随后的损伤（相同或不同类型的损伤）后，角膜的再上皮化速度更快，炎症细胞因子水平更低。在眼干燥综合征患者中，与感染性损伤前相比，经历感染性损伤后角膜点状上皮糜烂明显减少。这些结果表明，角膜上皮先前暴露于炎症刺激物会增强对二次攻击的角膜伤口愈合反应，这一现象表明角膜存在非特异性炎症记忆。
