The generation of new myelin-forming oligodendrocytes in the adult central nervous system is critical for cognitive function and regeneration following injury. Oligodendrogenesis varies between gray and white matter regions, suggesting that local cues drive regional differences in myelination and the capacity for regeneration. However, the layer- and region-specific regulation of oligodendrocyte populations is unclear due to the inability to monitor deep brain structures in vivo. Here we harnessed the superior imaging depth of three-photon microscopy to permit long-term, longitudinal in vivo three-photon imaging of the entire cortical column and subcortical white matter in adult mice. We find that cortical oligodendrocyte populations expand at a higher rate in the adult brain than those of the white matter. Following demyelination, oligodendrocyte replacement is enhanced in the white matter, while the deep cortical layers show deficits in regenerative oligodendrogenesis and the restoration of transcriptional heterogeneity. Together, our findings demonstrate that regional microenvironments regulate oligodendrocyte population dynamics and heterogeneity in the healthy and diseased brain.

成人中枢神经系统中新的髓磷脂形成少突胶质细胞的产生对于认知功能和损伤后的再生至关重要。灰质和白质区域之间的少突胶质细胞发生有所不同，这表明局部线索驱动了髓鞘形成和再生能力的区域差异。然而，由于无法监测体内深部脑结构，少突胶质细胞群的层和区域特异性调节尚不清楚。在这里，我们利用三光子显微镜的卓越成像深度，对成年小鼠的整个皮质柱和皮质下白质进行长期、纵向的体内三光子成像。我们发现，成人大脑中皮质少突胶质细胞群的扩张速度高于白质。脱髓鞘后，白质中的少突胶质细胞替代增强，而深层皮质层则显示出少突胶质细胞再生和转录异质性恢复的缺陷。总之，我们的研究结果表明，区域微环境调节健康和患病大脑中少突胶质细胞的群体动态和异质性。