Department of Ophthalmology, Oregon Health & Science University, Portland, OR, USA.
Department of Neurology, Oregon Health & Science University, Portland, OR, USA.
Methods Mol Biol. 2025;2858:49-62. doi: 10.1007/978-1-0716-4140-8_5.
Glaucoma causes dysfunction to tissues located in the anterior and posterior eye. In the anterior eye, the trabecular meshwork (TM) is the site of pathogenesis, where decreased TM cell numbers and alterations to the amount and composition of extracellular matrix hinder outflow of aqueous humor fluid from the anterior chamber. This causes intraocular pressure (IOP) elevation. Elevated IOP, a main risk factor for primary open-angle glaucoma, damages the axons of retinal ganglion cells in the posterior eye, which ultimately leads to blindness. Thus, clinical treatment paradigms for glaucoma are focused on reducing IOP. Normotensive IOPs are established by balancing the production of aqueous fluid from the ciliary body with drainage through the TM to Schlemm's canal. When IOP becomes elevated, TM cells coordinate a homeostatic response to lower IOP, which requires effective and efficient cellular communication. Tunneling nanotubes (TNTs) are transient specialized structures that allow cells to communicate with one another. Actin-rich tubes allow direct transmission of signals and cargoes between cells. This is important to overcome limitations of diffusion-based signaling in aqueous environments such as the anterior eye. Here, we describe a live-cell imaging method for monitoring TNTs in primary TM cells.
青光眼会导致眼前后部的组织功能障碍。在前眼部，小梁网 (TM) 是发病部位，TM 细胞数量减少以及细胞外基质的数量和组成发生改变，阻碍了前房房水的流出，从而导致眼内压 (IOP) 升高。IOP 升高是原发性开角型青光眼的主要危险因素，它会损害后眼部视网膜神经节细胞的轴突，最终导致失明。因此，青光眼的临床治疗模式侧重于降低 IOP。通过平衡睫状体产生的房水和通过 TM 到施莱姆氏管的排水来建立正常眼压。当 IOP 升高时，TM 细胞协调一种降低 IOP 的稳态反应，这需要有效的细胞间通讯。隧道纳米管 (TNTs) 是一种短暂的特殊结构，允许细胞之间进行通信。富含肌动蛋白的管允许在细胞之间直接传递信号和货物。这对于克服在前眼部等水性环境中基于扩散的信号传递的局限性非常重要。在这里，我们描述了一种用于监测原代 TM 细胞中 TNTs 的活细胞成像方法。
