Cytotoxic T lymphocyte attacking a cancer cell (jrc_ctl-id8-2)

Cytotoxic T lymphocytes (CTLs) kill virus-infected and tumorigenic cells through the polarized release of perforin and granzymes, which are housed in modified lysosomes called lytic granules. Perforin is a pore-forming toxin that creates an ephemeral portal in the plasma membrane of the target through which granzymes enter the cytosol and initiate apoptosis. This conjugate was captured moments after perforin secretion toward the target. Sample: OT-I mouse cytotoxic T lymphocyte attacking an ID8 ovarian cancer cell; fixed and imaged moments after the release of perforin/granzyme from lytic granules. The ID8 murine ovarian cancer cell is stably expressing mEmerald-Chmp4b and TOMM20-SNAP. Protocol: High pressure freezing, freeze-substitution resin embedding with 2% OsO4 0.1% UA 3% H2O in acetone; resin embedding in Eponate 12.Contributions: Sample provided by Alex Ritter (Genentech), prepared for imaging by Gleb Shtengel (HHMI/Janelia), with imaging and post-processing by C. Shan Xu (HHMI/Janelia).Dataset ID: jrc_ctl-id8-2Final voxel size (nm): 8 x 8 x 8 (X, Y, Z)Dimensions (µm): 50 x 9 x 62.9 (X, Y, Z)Acquisition date: 2019-10-18Dataset URL: https://data.janelia.org/ZFq0CVisualization Website: https://openorganelle.janelia.org/datasets/jrc_ctl-id8-2Publication: Ritter et al., ESCRT-mediated membrane repair at the immunological synapse protects tumor cells against T cell attack, Science (2022).细胞毒性T淋巴细胞（Cytotoxic T lymphocytes, CTLs）可通过极化释放穿孔素（perforin）与颗粒酶（granzymes），杀伤病毒感染细胞与致瘤细胞；这类效应分子储存在被称为溶细胞颗粒（lytic granules）的特化溶酶体中。穿孔素是一种成孔毒素，可在靶细胞质膜上形成短暂孔道，使颗粒酶得以进入胞质并启动细胞凋亡。本图像捕捉到了穿孔素向靶细胞分泌后即刻形成的细胞结合复合物。样本为OT-I小鼠细胞毒性T淋巴细胞攻击ID8卵巢癌细胞，在溶细胞颗粒释放穿孔素与颗粒酶后即刻完成固定并成像。该ID8小鼠卵巢癌细胞稳定表达mEmerald-Chmp4b与TOMM20-SNAP。实验方案：采用高压冷冻技术，以含2%四氧化锇、0.1%乙酸铀（UA）、3%水的丙酮溶液进行冷冻替代树脂包埋，随后使用Eponate 12树脂完成最终包埋。贡献说明：样本由Genentech的Alex Ritter提供，成像制样由HHMI/Janelia的Gleb Shtengel完成，成像与后期处理由HHMI/Janelia的C. Shan Xu完成。数据集编号：jrc_ctl-id8-2。最终体素尺寸（纳米）：8×8×8（X、Y、Z轴）。维度（微米）：50×9×62.9（X、Y、Z轴）。采集日期：2019-10-18。数据集网址：https://data.janelia.org/ZFq0C。可视化网站：https://openorganelle.janelia.org/datasets/jrc_ctl-id8-2。相关论文：Ritter 等，《ESCRT介导的免疫突触膜修复保护肿瘤细胞免受T细胞攻击》，《科学》（2022）。