Perforin 2 controls unconventional cytokine release from mucosal APC

穿孔蛋白2控制来自粘膜APC的非常规细胞因子释放 项目摘要 专业的抗原呈递细胞（APC）群体如何集中地将细胞因子递送至T细胞以塑造T细胞， 粘膜组织的促炎与抗炎状态仍然不完全清楚。特别是， 缺乏N-末端肽序列的细胞因子如IL-1家族细胞因子IL-33不能进入常规细胞因子， 蛋白质分泌途径，这导致了细胞死亡是IL-33释放的原因的流行观点。 这个项目是建立在一组令人兴奋的初步数据，表明粘膜传统树突状细胞， 人和小鼠的cDC亚群表达跨膜孔形成蛋白穿孔蛋白2， 至少在小鼠中，促进IL-33分泌。而在人cDC中，我们发现穿孔蛋白-2表达主要在 干扰素调节因子4（IRF 4）亚组指示cDC 2谱系，在小鼠cDC中，我们在小鼠cDC中发现穿孔蛋白-2（Perforin-2）。 已知表达转录因子Irf 8和Batf 3的CD 103 + cDC 1亚群。不管这个血统 不同的是，呼吸道粘膜中的人和小鼠CD 11 c+细胞都含有细胞质IL-33蛋白。 我们的数据表明，穿孔蛋白-2活性的抑制阻止了IL-33从cDC释放，并抑制了IL-33的表达。 ST 2 + GATA 3 + Foxp 3 +Treg亚群的增殖性扩增。考虑到穿孔蛋白-2已经被 显示也通过控制IFNAR反应性调节1型IFN信号传导，我们提出了一个重要的 在人类和小鼠中存在依赖于表达穿孔蛋白-2的粘膜APC的调节机制。 该项目测试了APC需要穿孔蛋白-2作为诱导质膜的中心假设 用于粘膜界面处的非常规细胞因子递送的导管。三个具体目标（SA）将是 研究了SA 1将确定穿孔蛋白-2 + APC是否预测鼻窦粘膜中的Treg亚群丰度 并定义穿孔蛋白-2 + APC的转录景观。SA 2将定义以下操作所需的穿孔蛋白-2域： IL-33释放、穿孔蛋白-2依赖性分泌分子的多样性和必需的细胞内运输 在APC-T细胞相互作用期间负责穿孔蛋白-2质膜定位的机械。SA 3将 直接检测cDC 1和/或cDC 2亚群是否优先使用穿孔蛋白-2驱动病原体特异性T细胞 呼吸道病毒或蠕虫感染的小鼠模型的反应。总的来说，这个MIST项目 揭示了一个新的范式，以了解cDC如何指导呼吸道粘膜内的免疫。

Perforin 2 controls unconventional cytokine release from mucosal APC Project Summary How professional antigen presenting cell (APC) populations focally deliver cytokines to T cells for shaping the pro-inflammatory vs. anti-inflammatory status of mucosal tissue remains incompletely understood. In particular, cytokines that lack N-terminal peptide sequence such as the IL-1 family cytokine IL-33 can't access conventional protein secretion pathways, which has led to the prevailing view that cell death is responsible for IL-33 release. This project is built upon an exciting set of preliminary data demonstrating that mucosal conventional dendritic cell (cDC) subsets, in both humans and mice, express the transmembrane pore-forming protein Perforin-2, which at least in mice, facilitates IL-33 secretion. While in human cDC, we find Perforin-2 expression primarily in an interferon regulatory factor 4 (IRF4) subset indicating the cDC2 lineage, in mouse cDC, we find Perforin-2 in the CD103+ cDC1 subset known to express the transcription factors Irf8 and Batf3. Irrespective of this lineage distinction, both human and mouse CD11c+ cells in the respiratory mucosa contain cytoplasmic IL-33 protein. Our data demonstrate that inhibition of Perforin-2 activity prevents IL-33 release from cDC and inhibits the proliferative expansion of a poorly understood ST2+GATA3+Foxp3+Treg subset. Given that Perforin-2 has been shown to also regulate Type 1 IFN signaling through controlling IFNAR responsiveness, we propose an important regulatory mechanism exists in humans and mice that is dependent upon mucosal APC that express Perforin-2. This project tests the central hypothesis that APC require Perforin-2 as an inducible plasma membrane conduit for unconventional cytokine delivery at the mucosal interface. Three specific aims (SA) will be investigated. SA1 will determine whether Perforin-2+ APC predict Treg subset abundance in sinonasal mucosa and define the transcriptional landscape of Perforin-2+ APC. SA2 will define the Perforin-2 domains required for IL-33 release, the diversity of Perforin-2-dependent secreted molecules, and the requisite intracellular trafficking machinery responsible for Perforin-2 plasma membrane localization during APC-T cell interactions. SA3 will directly test whether cDC1 and/or cDC2 subsets preferentially use Perforin-2 for driving pathogen-specific T cell responses in mouse models of respiratory virus or helminth infection. Taken together, this MIST project stands to uncover a new paradigm for understanding how cDC instruct immunity within the respiratory mucosa.