早期染色体重塑事件在急性刺激的CD8+ T细胞中
Bryan McDonald1,2, Brent Y Chick3,4, Diana C Hargreaves3
1NOMIS Center for Immunobiology and Microbial Pathogenesis, Salk Institute for Biological Studies, La Jolla, CA, USA.
The Yale journal of biology and medicine
|January 1, 2024
概括
早期的T细胞激活迅速重塑染色质,在1小时内增强效应基因可访问性. 克隆扩张需要持续24小时的持续刺激,这表明抗原歧视的持续时间依赖机制.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 在T细胞受体 (TCR) 刺激后,T细胞需要广泛的染色质重塑以实现因子分化.
- 在T细胞原始化后24小时内,早期染色质重塑事件的精确时间和基因标仍然不太清楚.
研究的目的:
- 为了研究早期激活期间CD8+ T细胞中染色质可访问性变化的动力学.
- 确定特定的基因位置和转录因子结合部位,参与早期T细胞原始化.
- 确定刺激持续时间,染色体重塑和T细胞克隆扩张之间的关系.
主要方法:
- 刺激原始的CD8+T细胞,短期 (1小时) 和持续 (24小时) 的时间.
- 全球和基因特异性染色质可访问性的评估.
- 在改造的位置分析转录因子结合部位的丰富.
- 在不同的刺激持续时间后,对克隆扩张in vivo的评估.
主要成果:
- 在T细胞受体刺激后1小时内发生了快速和广泛的染色质可访问性变化.
- 早期重塑的目标是对AP-1,EGR和NFAT结合部位进行丰富的效应T细胞相关基因.
- 短期刺激 (1小时) 对于体内克隆扩张是不够的,而24小时的刺激可以实现.
结论:
- 抗原受体信号持续时间对于合染色体重塑与T细胞中的效应基因激活至关重要.
- 这些发现揭示了一种机制,CD8+ T细胞可以根据信号持续时间来区分外来和自身抗原.
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