Sarcoidosis is a disease characterised by granuloma formation. There is an unmet need for new treatment strategies beyond corticosteroids. The NLRP3 inflammasome pathway is expressed in innate immune cells and senses danger signals to elicit inflammatory interleukin (IL)-1β; it has recently become a druggable target. This prompted us to test the role of the NLRP3 inflammasome and IL-1β pathway in granuloma formation and sarcoidosis. 19 sarcoid patients and 19 healthy volunteers were recruited into this pilot study. NLRP3 inflammasome activity was measured in bronchoalveolar lavage (BAL) cells and lung and skin biopsies using immunohistochemistry, Western blot, reverse-transcriptase PCR and ELISA. For in vivo experiments we used the trehalose 6,6′-dimycolate-granuloma mouse model and evaluated lung granuloma burden in miR-223 knockout and NLRP3 knockout mice, as well as the treatment effects of MCC950 and anti-IL-1β antibody therapy. We found strong upregulation of the NLRP3 inflammasome pathway, evidenced by expression of activated NLRP3 inflammasome components, including cleaved caspase-1 and IL-1β in lung granuloma, and increased IL-1β release of BAL cells from sarcoid patients compared to healthy volunteers (p=0.006). mRNA levels of miR-223, a micro-RNA downregulating NLRP3, were decreased and NLRP3 mRNA correspondingly increased in alveolar macrophages from sarcoid patients (p<0.005). NLRP3 knockout mice showed decreased and miR-223 knockout mice increased granuloma formation compared to wild-type mice. Pharmacological interference using NLRP3 pathway inhibitor MCC950 or an anti-IL-1β antibody resulted in reduced granuloma formation (p<0.02). In conclusion, our data provide evidence of upregulated inflammasome and IL-1β pathway activation in sarcoidosis and suggest both as valid therapeutic targets. This pilot study underscores a pivotal role for the NLRP3 inflammasome and MIR-223 in the pathogenesis of sarcoidosis. A beneficial effect of a NLRP3 inflammasome pathway inhibitor and an anti-IL-1β antibody on granuloma formation is demonstrated. http://bit.ly/36StvLe

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NLRP3 炎性体通路在结节病中被激活并参与肉芽肿的形成

结节病是一种以肉芽肿形成为特征的疾病。对除皮质类固醇之外的新治疗策略的需求未得到满足。NLRP3 炎症小体通路在先天免疫细胞中表达并感知危险信号以引发炎症性白细胞介素 (IL)-1β；它最近已成为可药物靶点。这促使我们测试 NLRP3 炎症小体和 IL-1β 通路在肉芽肿形成和结节病中的作用。19 名肉瘤患者和 19 名健康志愿者被招募到这项试点研究中。使用免疫组织化学、蛋白质印迹、逆转录酶 PCR 和 ELISA 在支气管肺泡灌洗 (BAL) 细胞和肺和皮肤活检中测量 NLRP3 炎性体活性。对于体内实验，我们使用了海藻糖 6，6'-二分枝杆菌肉芽肿小鼠模型并评估了 miR-223 敲除和 NLRP3 敲除小鼠的肺肉芽肿负荷，以及 MCC950 和抗 IL-1β 抗体疗法的治疗效果。我们发现 NLRP3 炎症小体通路的强烈上调，这通过激活的 NLRP3 炎症小体成分的表达来证明，包括肺肉芽肿中裂解的 caspase-1 和 IL-1β，与健康志愿者相比，肉瘤患者 BAL 细胞的 IL-1β 释放增加（p =0.006）。来自肉瘤患者的肺泡巨噬细胞中，miR-223（一种下调 NLRP3 的微 RNA）的 mRNA 水平降低，NLRP3 mRNA 相应增加（p<0.005）。与野生型小鼠相比，NLRP3 敲除小鼠表现出减少，而 miR-223 敲除小鼠增加了肉芽肿形成。使用 NLRP3 通路抑制剂 MCC950 或抗 IL-1β 抗体的药理学干扰导致肉芽肿形成减少（p<0.02）。总之，我们的数据提供了结节病中炎症小体和 IL-1β 通路激活上调的证据，并表明两者都是有效的治疗靶点。这项初步研究强调了 NLRP3 炎症小体和 MIR-223 在结节病发病机制中的关键作用。证明了 NLRP3 炎性体通路抑制剂和抗 IL-1β 抗体对肉芽肿形成的有益作用。http://bit.ly/36StvLe 这项初步研究强调了 NLRP3 炎症小体和 MIR-223 在结节病发病机制中的关键作用。证明了 NLRP3 炎性体通路抑制剂和抗 IL-1β 抗体对肉芽肿形成的有益作用。http://bit.ly/36StvLe 这项初步研究强调了 NLRP3 炎症小体和 MIR-223 在结节病发病机制中的关键作用。证明了 NLRP3 炎性体通路抑制剂和抗 IL-1β 抗体对肉芽肿形成的有益作用。http://bit.ly/36StvLe