We made a spot injury of microvessel in the somatosensory cortex to mimic the model of CMBs by two-photon laser and in vivo tracked dynamical behaviors of γδ T cells induced by CMBs using TCR-δGFP transgenic mice. Biological features of γδ T cells in the peri-CMBs parenchyma were decoded by flow cytometry and Raman spectra. In wildtype and γδ T cell-deficient mice, neuroinflammation and neurite degeneration in the peri-CMBs cortex were studied by RNAseq, immunostaining and in vivo imaging respectively.
After CMBs, γδ T cells in the dural vessels were tracked to cross the meningeal structure and invade the brain parenchyma in a few days, where the division process of γδ T cells were captured. Parenchymal γδ T cells were highly expressed by CXCR6 and CCR6, similar to meningeal γδ T cells, positive for IL-17A and Ki67 (more than 98%), and they contained abundant substances for energy metabolism and nucleic acid synthesis. In γδ T cell-deficient mice, cortical samples showed the upregulation of neuroinflammatory signaling pathways, enhanced glial response and M1 microglial polarization, and earlier neuronal degeneration in the peri-CMBs brain parenchyma compared with wildtype mice.
CMBs induce the accumulation and local proliferation of γδ T cells in the brain parenchyma, and γδ T cells exert anti-neuroinflammatory and neuroprotective effects at the early stage of CMBs.
■我们通过双光子激光模拟CMBs模型,并在体内使用TCR-δGFP转基因小鼠跟踪CMBs诱导的γδT细胞的动力学行为。通过流式细胞术和拉曼光谱解码了外周CMBs实质中γδT细胞的生物学特征。在野生型和γδT细胞缺陷小鼠中,通过RNAseq研究了CMBs周围皮质的神经炎症和神经突变性,免疫染色和体内成像。
■在CMB之后,追踪硬脑膜血管中的γδT细胞穿过脑膜结构并在几天内侵入脑实质,其中捕获了γδT细胞的分裂过程。CXCR6和CCR6高表达实质γδT细胞,与脑膜γδT细胞相似,IL-17A和Ki67阳性(98%以上),它们含有丰富的能量代谢和核酸合成物质。在γδT细胞缺陷小鼠中,皮质样本显示了神经炎症信号通路的上调,增强的神经胶质反应和M1小胶质细胞极化,与野生型小鼠相比,CMBs周围脑实质的神经元变性较早。
■CMBs诱导γδT细胞在脑实质中的积累和局部增殖,γδT细胞在CMBs早期发挥抗神经炎和神经保护作用。