Data Sheet 1_Molecular and subcellular mechanisms of vital macrophage extracellular trap formation.pdf

Macrophage extracellular traps (METs) are a poorly understood process beneficial for infection control but detrimental in inflammation, autoimmunity and cancer. Our research shows that viable macrophages release METs even when plasma membrane lysis is blocked. We demonstrate, for the first time, that nuclear DNA is extruded directly into the cytoplasm through Gasdermin D pores on the nuclear envelope. Gasdermin D pore formation was triggered by extracellular cold-inducible RNA-binding protein, which activates the TLR4 signal transduction pathway. This DNA is processed in the cytoplasm, enters the vesicular transport system aided by autophagic flux and the Endosomal Sorting Complex. The DNA then enters the lysosomal compartment, where it undergoes histone 3 citrullination, forms nascent traps containing myeloperoxidase, and is released to the extracellular space. Our study provides valuable insights into vital MET formation and its mechanism that will enable future studies on the role of METs in health and disease.

巨噬细胞胞外陷阱（Macrophage extracellular traps，METs）是一类目前尚缺乏深入研究的生物学过程：其在感染防控中发挥有益作用，但在炎症、自身免疫病及癌症发生过程中则会产生有害影响。本研究证实，即使细胞膜裂解被阻断，存活的巨噬细胞仍可释放METs。本研究首次发现，细胞核DNA可通过核膜上的Gasdermin D（焦亡素D）孔道直接被挤出至细胞质内。细胞外的冷诱导RNA结合蛋白可触发Gasdermin D孔道的形成，该蛋白能够激活Toll样受体4（TLR4）信号转导通路。该DNA在细胞质中被加工，并在自噬流（autophagic flux）与内体分选复合物（Endosomal Sorting Complex）的辅助下进入囊泡运输系统。随后DNA进入溶酶体区室，在此发生组蛋白H3瓜氨酸化（histone 3 citrullination）修饰，形成包含髓过氧化物酶（myeloperoxidase）的新生陷阱，并最终被释放至细胞外空间。本研究为MET的关键形成过程及其分子机制提供了宝贵见解，将为后续探究MET在健康与疾病中的作用提供重要支撑。