在IRF8突变B细胞淋巴瘤中,通过在MHC CII复合体中对抗原处理和呈现的CD74依赖性放松调节来逃避免疫力
bioRxiv : the preprint server for biology
|October 24, 2023
概括
在扩散性大B细胞淋巴瘤 (DLBCL) 中IRF8基因的突变会损害免疫监测. 这些IRF8变体通过改变抗原呈现和重塑瘤微环境来促进瘤生长,从而促进免疫逃生.
科学领域:
- 在瘤学瘤学.
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
背景情况:
- 扩散性大B细胞淋巴瘤 (DLBCL) 是一种异质癌症,其瘤性事件向IRF8转录因子.
- 在DLBCL淋巴发育中IRF8突变的功能影响仍然在很大程度上是未知的.
- 在DLBCL中经常观察到IRF8突变,这表明它在疾病进展中的作用.
研究的目的:
- 研究DLBCL中IRF8突变的功能后果.
- 阐明IRF8变种对淋巴发育和免疫逃避有所贡献的机制.
- 探索针对IRF8介导的免疫逃脱的治疗潜力.
主要方法:
- 使用体外和体外系统在DLBCL中IRF8突变的建模.
- 对包括CIITA在内的目标基因上的IRF8转录活性进行分析.
- 在IRF8突变淋巴瘤中评估抗原呈现途径 (MHCII类复合物,CD74,HLA-DM).
- 在IRF8-突变小鼠模型中,瘤微环境 (TME) 和免疫细胞种群的表征.
- 对CD74再表达对淋巴瘤表型的影响的评估.
- 从人类DLBCL样本中大量RNA测序数据的解卷.
主要成果:
- IRF8突变降低了其对CIITA的转录活性,但不会影响细胞适应性.
- 在DLBCL中,IRF8突变与抗原呈现基因突变相互排斥.
- IRF8突变抑制CD4+T细胞激活,并降低CD74和HLA-DM的调节,影响抗原处理.
- IRF8突变淋巴瘤表现出增加的瘤负担和重塑的TME,免疫细胞组成发生变化 (效应细胞减少,调节细胞增加).
- 宫外CD74表达拯救了IRF8突变淋巴瘤的临床和免疫表型.
- 人类DLBCL数据证实IRF8突变瘤中的免疫重塑和树突细胞枯竭.
结论:
- 在DLBCL中的IRF8突变通过促进免疫逃生,有助于淋巴发育.
- 改变的抗原处理和TME重塑是IRF8驱动的免疫逃避的关键机制.
- 向CD74或恢复IRF8功能可能代表DLBCL的新疗法策略.
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