Decotret Lisa R, Shi Rocky, Thomas Kiersten N, Hsu Manchi, Pallen Catherine J, Bennewith Kevin L
Department of Integrative Oncology, BC Cancer, Vancouver, BC, Canada.
Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
Front Oncol. 2023 Jan 26;13:976945. doi: 10.3389/fonc.2023.976945. eCollection 2023.
Organotypic cultures of murine brain slices are well-established tools in neuroscience research, including electrophysiology studies, modeling neurodegeneration, and cancer research. Here, we present an optimized brain slice invasion assay that models glioblastoma multiforme (GBM) cell invasion into organotypic brain slices. Using this model, human GBM spheroids can be implanted with precision onto murine brain slices and cultured to allow tumour cell invasion into the brain tissue. Traditional top-down confocal microscopy allows for imaging of GBM cell migration along the top of the brain slice, but there is limited resolution of tumour cell invasion into the slice. Our novel imaging and quantification technique involves embedding stained brain slices into an agar block, re-sectioning the slice in the Z-direction onto slides, and then using confocal microscopy to image cellular invasion into the brain tissue. This imaging technique allows for the visualization of invasive structures beneath the spheroid that would otherwise go undetected using traditional microscopy approaches. Our ImageJ macro (BraInZ) allows for the quantification of GBM brain slice invasion in the Z-direction. Importantly, we note striking differences in the modes of motility observed when GBM cells invade into Matrigel versus into brain tissue highlighting the importance of incorporating the brain microenvironment when studying GBM invasion. In summary, our version of the brain slice invasion assay improves upon previously published models by more clearly differentiating between migration along the top of the brain slice versus invasion into the slice.
小鼠脑片的器官型培养是神经科学研究中成熟的工具，包括电生理学研究、神经退行性变建模和癌症研究。在此，我们展示了一种优化的脑片侵袭试验，该试验模拟多形性胶质母细胞瘤（GBM）细胞侵入器官型脑片。使用该模型，可以将人GBM球体精确植入小鼠脑片并进行培养，以使肿瘤细胞侵入脑组织。传统的自上而下共聚焦显微镜可以对GBM细胞沿脑片顶部的迁移进行成像，但肿瘤细胞侵入脑片的分辨率有限。我们新颖的成像和定量技术包括将染色的脑片嵌入琼脂块中，在Z方向上重新切片到载玻片上，然后使用共聚焦显微镜对细胞侵入脑组织进行成像。这种成像技术可以可视化球体下方的侵袭性结构，而使用传统显微镜方法则无法检测到这些结构。我们的ImageJ宏（BraInZ）可以对GBM脑片在Z方向上的侵袭进行定量。重要的是，我们注意到当GBM细胞侵入基质胶与侵入脑组织时观察到的运动模式存在显著差异，这突出了在研究GBM侵袭时纳入脑微环境的重要性。总之，我们版本的脑片侵袭试验在先前发表的模型基础上进行了改进，通过更清晰地区分沿脑片顶部的迁移与侵入脑片的情况。
