Kelley M W, Talreja D R, Corwin J T
Department of Otolaryngology-HNS, University of Virginia School of Medicine, Charlottesville 22908, USA.
J Neurosci. 1995 Apr;15(4):3013-26. doi: 10.1523/JNEUROSCI.15-04-03013.1995.
This study examined the potential for hair cell regeneration in embryonic and neonatal mouse organs of Corti maintained in vitro. Small numbers of hair cells were killed by laser microbeam irradiation and the subsequent recovery processes were monitored by differential interference contrast (DIC) microscopy combined with continuous time-lapse video recordings. Replacement hair cells were observed to develop in lesion sites in embryonic cochleae and on rare occasions in neonatal cochleae. In embryonic cochleae, replacement hair cells did not arise through renewed proliferation, but instead developed from preexisting cells that changed from their normal developmental fates in response to the loss of adjacent hair cells. In cochleae established from neonates, lost hair cells usually were not replaced, but 11 apparently regenerated hair cells and a single hair cell labeled by 3H-thymidine were observed as rare responses to the creation of hair cell lesions in these organs. The results indicate that the organ of Corti can replace lost hair cells during embryonic and on rare occasions during early neonatal development. The ability of preexisting cells to change their developmental fates in response to hair cell death is consistent with the hypothesis that during embryonic development hair cells may inhibit neighboring cells from specializing as hair cells. In neonatal cultures, the rare occurrence of apparently regenerated hair cells indicates that some cells in the postembryonic organ of Corti retain response mechanisms that can lead to self-repair.
本研究检测了体外培养的胚胎和新生小鼠柯蒂氏器中毛细胞再生的可能性。用激光微束照射杀死少量毛细胞，并通过微分干涉相差（DIC）显微镜结合连续延时视频记录来监测随后的恢复过程。观察到在胚胎期耳蜗的损伤部位以及在新生期耳蜗极个别情况下有替代毛细胞生成。在胚胎期耳蜗中，替代毛细胞并非通过重新增殖产生，而是由原本的细胞发育而来，这些细胞因相邻毛细胞缺失而改变了其正常发育命运。在新生小鼠建立的耳蜗中，缺失的毛细胞通常不会被替代，但在这些器官中造成毛细胞损伤后，观察到有11个明显再生的毛细胞以及1个被3H-胸腺嘧啶标记的单个毛细胞，这是罕见的反应。结果表明，柯蒂氏器在胚胎期以及在新生早期极个别情况下能够替代缺失的毛细胞。原本的细胞响应毛细胞死亡而改变其发育命运的能力与以下假说相符，即在胚胎发育过程中，毛细胞可能会抑制相邻细胞特化为毛细胞。在新生期培养物中，明显再生的毛细胞罕见出现表明，胚胎后柯蒂氏器中的一些细胞保留了可导致自我修复的反应机制。
