Original lncRNA sequencing data in Fig 1A.

Host defenses are crucial in deciding the fate of Mycobacterium tuberculosis (Mtb) infections, as less than 10% of infected individuals develop tuberculosis. Oxidative stress plays a critical role in the host defense against Mtb. However, the mechanisms by which Mtb modulates redox homeostasis to evade immune responses remain poorly understood. In this study, we primarily identified a pathogen-responsive long noncoding RNA, LINC02528, which was selectively upregulated in peripheral blood mononuclear cells (PBMCs) from tuberculosis (TB) patients. In Mtb-infected macrophages, LINC02528 dynamically relocalizes from the nucleus to the cytoplasm. Functionally, CRISPR-Cas9-mediated knockout (KO) of LINC02528 in macrophages resulted in reduced Mtb survival concurrent with an elevated IL-1β expression. Importantly, these antimicrobial effects were abrogated by IL-1 receptor antagonist (IL-RA) treatment. Interestingly, LINC02528 was found to directly bind to TOMM22, a mitochondrial outer membrane translocase, as validated by co-localization analysis using in situ hybridization of lung tissue sections from a TB patient. The ECAR results revealed that LINC02528 deficiency significantly increased glycolysis and elevated Mtb-induced mitochondrial ROS (mtROS) production. Notably, TOMM22 knockdown phenocopied LINC02528 deletion effects, suggesting functional interdependence in modulating mitochondrial dynamics and the host’s anti-TB immunity. Collectively, our findings reveal a novel strategy wherein Mtb hijacks the lncRNA-mitochondrial axis to rewire redox-metabolic checkpoints to favor immune evasion. Targeting LINC02528 could dually disrupt the pathogen-permissive redox balance and activate mtROS-IL-1β-mediated antimicrobial defense, offering novel therapeutic avenues for TB.

宿主防御系统在决定结核分枝杆菌（Mycobacterium tuberculosis, Mtb）感染的转归中发挥关键作用，因为仅不足10%的感染者会发展为结核病（tuberculosis, TB）。氧化应激在宿主抗结核分枝杆菌的防御过程中扮演核心角色。然而，结核分枝杆菌调控氧化还原稳态以逃避免疫应答的具体分子机制仍不甚明确。本研究首先鉴定出一种病原体应答性长链非编码RNA（long noncoding RNA, lncRNA）LINC02528，该分子在结核病患者的外周血单个核细胞（peripheral blood mononuclear cells, PBMCs）中呈选择性上调表达。在结核分枝杆菌感染的巨噬细胞中，LINC02528会从细胞核向细胞质发生动态易位。功能实验显示，在巨噬细胞中通过CRISPR-Cas9介导敲除（knockout, KO）LINC02528，可使结核分枝杆菌的存活能力下降，同时伴随白细胞介素1β（IL-1β）表达水平升高。值得注意的是，白细胞介素1受体拮抗剂（IL-1 receptor antagonist, IL-RA）处理可抵消上述抗菌效应。有趣的是，通过对结核病患者肺组织切片进行原位杂交（in situ hybridization）共定位分析验证，发现LINC02528可直接结合线粒体外膜转位酶TOMM22。细胞外酸化率（extracellular acidification rate, ECAR）检测结果显示，敲低LINC02528可显著增强糖酵解水平，并提高结核分枝杆菌诱导的线粒体活性氧（mitochondrial ROS, mtROS）生成量。值得关注的是，敲低TOMM22可重现LINC02528缺失所产生的表型效应，提示二者在调控线粒体动态平衡与宿主抗结核病免疫过程中存在功能互作。综上，本研究结果揭示了一种全新的致病策略：结核分枝杆菌通过劫持长链非编码RNA-线粒体轴，重编程氧化还原代谢检查点以实现免疫逃逸。靶向干预LINC02528可同时破坏病原体容许性氧化还原平衡，并激活线粒体活性氧-白细胞介素1β介导的抗菌防御通路，为结核病治疗提供全新的潜在治疗途径。