Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.
Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada.
Front Immunol. 2021 Apr 22;12:668483. doi: 10.3389/fimmu.2021.668483. eCollection 2021.
To fully perform their functions, T lymphocytes migrate within organs' parenchyma and interact with local cells. Infiltration of T lymphocytes within the central nervous system (CNS) is associated with numerous neurodegenerative disorders. Nevertheless, how these immune cells communicate and respond to neural cells remains unresolved. To investigate the behavior of T lymphocytes that reach the CNS, we have established an co-culture model and analyzed the spatiotemporal interactions between human activated CD8 T lymphocytes and primary human astrocytes and neurons using time-lapse microscopy. By combining multiple variables extracted from individual CD8 T cell tracking, we show that CD8 T lymphocytes adopt a more motile and exploratory behavior upon interacting with astrocytes than with neurons. Pretreatment of astrocytes or neurons with IL-1β to mimic inflammation significantly increases CD8 T lymphocyte motility. Using visual interpretation and analysis of numerical variables extracted from CD8 T cell tracking, we identified four distinct CD8 T lymphocyte behaviors: scanning, dancing, poking and round. IL-1β-pretreatment significantly increases the proportion of scanning CD8 T lymphocytes, which are characterized by active exploration, and reduces the proportion of round CD8 T lymphocytes, which are less active. Blocking MHC class I on astrocytes significantly diminishes the proportion of poking CD8 T lymphocytes, which exhibit synapse-like interactions. Lastly, our co-culture time-lapse model is easily adaptable and sufficiently sensitive and powerful to characterize and quantify spatiotemporal interactions between human T lymphocytes and primary human cells in different conditions while preserving viability of fragile cells such as neurons and astrocytes.
为了充分发挥其功能，T 淋巴细胞在器官实质内迁移并与局部细胞相互作用。T 淋巴细胞浸润中枢神经系统（CNS）与许多神经退行性疾病有关。然而，这些免疫细胞如何相互通信并对神经细胞做出反应仍未解决。为了研究到达中枢神经系统的 T 淋巴细胞的行为，我们建立了共培养模型，并使用延时显微镜分析了人激活的 CD8 T 淋巴细胞与原代人星形胶质细胞和神经元之间的时空相互作用。通过结合从单个 CD8 T 细胞跟踪中提取的多个变量，我们表明 CD8 T 淋巴细胞与星形胶质细胞相互作用时比与神经元相互作用时表现出更具迁移性和探索性的行为。用白细胞介素 1β预处理星形胶质细胞或神经元以模拟炎症显著增加了 CD8 T 淋巴细胞的迁移率。通过对 CD8 T 细胞跟踪中提取的数值变量进行视觉解释和分析，我们确定了四种不同的 CD8 T 淋巴细胞行为：扫描、跳舞、戳刺和圆形。白细胞介素 1β预处理显著增加了扫描 CD8 T 淋巴细胞的比例，这些细胞表现出活跃的探索行为，减少了不那么活跃的圆形 CD8 T 淋巴细胞的比例。在星形胶质细胞上阻断 MHC 类 I 显著减少了表现出突触样相互作用的刺戳 CD8 T 淋巴细胞的比例。最后，我们的共培养延时模型易于适应，并且足够灵敏和强大，可以在不同条件下对人类 T 淋巴细胞和原代人类细胞之间的时空相互作用进行特征描述和量化，同时保持神经元和星形胶质细胞等脆弱细胞的活力。
