Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892.
Inflammatory Disease Section, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892.
Proc Natl Acad Sci U S A. 2017 Sep 12;114(37):E7766-E7775. doi: 10.1073/pnas.1702946114. Epub 2017 Aug 28.
The NLRP3 inflammasome is an intracellular innate immune sensor that is expressed in immune cells, including monocytes and macrophages. Activation of the NLRP3 inflammasome leads to IL-1β secretion. Gain-of-function mutations of result in abnormal activation of the NLRP3 inflammasome, and cause the autosomal dominant systemic autoinflammatory disease spectrum, termed cryopyrin-associated periodic syndromes (CAPS). Here, we show that a missense mutation, p.Arg918Gln (c.2753G > A), of causes autosomal-dominant sensorineural hearing loss in two unrelated families. In family LMG446, hearing loss is accompanied by autoinflammatory signs and symptoms without serologic evidence of inflammation as part of an atypical CAPS phenotype and was reversed or improved by IL-1β blockade therapy. In family LMG113, hearing loss segregates without any other target-organ manifestations of CAPS. This observation led us to explore the possibility that resident macrophage/monocyte-like cells in the cochlea can mediate local autoinflammation via activation of the NLRP3 inflammasome. The NLRP3 inflammasome can indeed be activated in resident macrophage/monocyte-like cells in the mouse cochlea, resulting in secretion of IL-1β. This pathway could underlie treatable sensorineural hearing loss in DFNA34, CAPS, and possibly in a wide variety of hearing-loss disorders, such as sudden sensorineural hearing loss and Meniere's disease that are elicited by pathogens and processes that stimulate innate immune responses within the cochlea.
NLRP3 炎性体是一种存在于免疫细胞(包括单核细胞和巨噬细胞)中的细胞内先天免疫传感器。NLRP3 炎性体的激活导致白细胞介素 1β(IL-1β)的分泌。导致 NLRP3 炎性体异常激活的功能获得性突变会引起常染色体显性全身自身炎症性疾病谱,称为 Cryopyrin 相关周期性综合征(CAPS)。在这里,我们表明,一个错义突变,p.Arg918Gln(c.2753G > A),导致两个不相关的家族常染色体显性感觉神经性听力损失。在 LMG446 家族中,听力损失伴随着自身炎症迹象和症状,但没有炎症的血清学证据,作为不典型 CAPS 表型的一部分,并且通过 IL-1β 阻断治疗逆转或改善。在 LMG113 家族中,听力损失没有 CAPS 的任何其他靶器官表现而分离。这一观察结果使我们探讨了耳蜗内驻留巨噬细胞/单核细胞样细胞是否可以通过激活 NLRP3 炎性体来介导局部自身炎症的可能性。NLRP3 炎性体确实可以在小鼠耳蜗内的驻留巨噬细胞/单核细胞样细胞中被激活,导致白细胞介素 1β(IL-1β)的分泌。这条途径可能是 DFNA34、CAPS 以及可能的各种听力损失疾病(如由病原体和刺激耳蜗内先天免疫反应的过程引起的突发性感觉神经性听力损失和梅尼埃病)的可治疗性感觉神经性听力损失的基础。