Observation of the Ciliary Movement of Choroid Plexus Epithelial Cells Ex Vivo

The choroid plexus is located in the ventricular wall of the brain, the main function of which is believed to be production of cerebrospinal fluid. Choroid plexus epithelial cells (CPECs) covering the surface of choroid plexus tissue harbor multiple unique cilia, but most of the functions of these cilia remain to be investigated. To uncover the function of CPEC cilia with particular reference to their motility, an ex vivo observation system was developed to monitor ciliary motility during embryonic, perinatal and postnatal periods. The choroid plexus was dissected out of the brain ventricle and observed under a video-enhanced contrast microscope equipped with differential interference contrast optics. Under this condition, a simple and quantitative method was developed to analyze the motile profiles of CPEC cilia for several hours ex vivo. Next, the morphological changes of cilia during development were observed by scanning electron microscopy to elucidate the relationship between the morphological maturity of cilia and motility. Interestingly, this method could delineate changes in the number and length of cilia, which peaked at postnatal day (P) 2, while the beating frequency reached a maximum at P10, followed by abrupt cessation at P14. These techniques will enable elucidation of the functions of cilia in various tissues. While related techniques have been published in a previous report(1), the current study focuses on detailed techniques to observe the motility and morphology of CPEC cilia ex vivo.

脉络丛位于脑室壁，其主要功能被认为是产生脑脊液。覆盖脉络丛组织表面的脉络丛上皮细胞（CPECs）具有多个独特的纤毛，但这些纤毛的大部分功能仍有待研究。为了揭示CPEC纤毛的功能，特别是其运动性，开发了一种体外观察系统，以监测胚胎期、围产期和出生后时期的纤毛运动性。将脉络丛从脑室中解剖出来，在配备微分干涉对比光学系统的视频增强对比显微镜下进行观察。在此条件下，开发了一种简单的定量方法，用于在体外分析CPEC纤毛数小时的运动特征。接下来，通过扫描电子显微镜观察发育过程中纤毛的形态变化，以阐明纤毛的形态成熟度与运动性之间的关系。有趣的是，这种方法可以描绘出纤毛数量和长度的变化，其在出生后第2天达到峰值，而摆动频率在出生后第10天达到最大值，随后在出生后第14天突然停止。这些技术将有助于阐明纤毛在各种组织中的功能。虽然相关技术已在先前的一份报告中发表，但当前的研究侧重于详细的体外观察CPEC纤毛运动性和形态的技术。