Cornea and External Disease, Department of Ophthalmology, USF Health, 13330 USF Laurel Dr 4th floor, Tampa FL 33612, USA.
Universidad Nacional de Colombia, Department of Ophthalmology, Bogota 111311, Colombia.
Dis Model Mech. 2023 Sep 1;16(9). doi: 10.1242/dmm.050090. Epub 2023 Sep 13.
Every tissue has an extracellular matrix (ECM) with certain properties unique to it - the tissue 'niche' - that are necessary for normal function. A distinct specific population of quiescent keratocan-expressing keratocytes populate the corneal stroma during homeostasis to maintain corneal function. However, during wound healing, when there is alteration of the niche conditions, keratocytes undergo apoptosis, and activated corneal fibroblasts and myofibroblasts attempt to restore tissue integrity and function. It is unknown what the fate of activated and temporary fibroblasts and myofibroblasts is after the wound healing process has resolved. In this study, we used several strategies to elucidate the cellular dynamics of corneal wound healing and the fate of corneal fibroblasts. We injured the cornea of a novel mouse model that allows cell-lineage tracing, and we transplanted a cell suspension of in vitro-expanded corneal fibroblasts that could be tracked after being relocated into normal stroma. These transplanted fibroblasts regained expression of keratocan in vivo when relocated to a normal stromal niche. These findings suggest that transformed fibroblasts maintain plasticity and can be induced to a keratocyte phenotype once relocated to an ECM with normal signaling ECM.
每个组织都有其特有的细胞外基质 (ECM),这些特性对其正常功能是必需的——这就是组织的“生态位”。在稳态下,角膜基质中存在一群静止的角膜蛋白聚糖表达的角膜细胞,以维持角膜功能。然而,在伤口愈合过程中,当生态位条件发生改变时,角膜细胞会发生凋亡,而激活的角膜成纤维细胞和成肌纤维细胞会试图恢复组织的完整性和功能。目前尚不清楚伤口愈合过程结束后,激活和暂时的成纤维细胞和成肌纤维细胞的命运如何。在这项研究中,我们使用了几种策略来阐明角膜伤口愈合的细胞动力学和角膜成纤维细胞的命运。我们损伤了一种新型小鼠模型的角膜,这种模型允许细胞谱系追踪,我们移植了体外扩增的角膜成纤维细胞的细胞悬液,这些细胞在重新定位到正常基质后可以被追踪。这些重新定位到正常基质生态位的移植成纤维细胞在体内重新表达了角膜蛋白聚糖。这些发现表明,转化的成纤维细胞保持着可塑性,一旦被重新定位到具有正常信号 ECM 的 ECM 中,就可以被诱导为角膜细胞表型。