Abstract：
Chronic nonbacterial osteomyelitis (CNO), an autoinflammatory bone disease primarily affecting children, can cause pain, hyperostosis and fractures, affecting quality-of-life and psychomotor development. This study investigated CNO-associated variants in P2RX7, encoding for the ATP-dependent trans-membrane K+ channel P2X7, and their effects on NLRP3 inflammasome assembly. Whole exome sequencing in two related transgenerational CNO patients, and target sequencing of P2RX7 in a large CNO cohort (N = 190) were conducted. Results were compared with publicly available datasets and regional controls (N = 1873). Findings were integrated with demographic and clinical data. Patient-derived monocytes and genetically modified THP-1 cells were used to investigate potassium flux, inflammasome assembly, pyroptosis, and cytokine release. Rare presumably damaging P2RX7 variants were identified in two related CNO patients. Targeted P2RX7 sequencing identified 62 CNO patients with rare variants (32.4%), 11 of which (5.8%) carried presumably damaging variants (MAF <1%, SIFT \"deleterious\", Polyphen \"probably damaging\", CADD >20). This compared to 83 of 1873 controls (4.4%), 36 with rare and presumably damaging variants (1.9%). Across the CNO cohort, rare variants unique to one (Median: 42 versus 3.7) or more (≤11 patients) participants were over-represented when compared to 190 randomly selected controls. Patients with rare damaging variants more frequently experienced gastrointestinal symptoms and lymphadenopathy while having less spinal, joint and skin involvement (psoriasis). Monocyte-derived macrophages from patients, and genetically modified THP-1-derived macrophages reconstituted with CNO-associated P2RX7 variants exhibited altered potassium flux, inflammasome assembly, IL-1β and IL-18 release, and pyroptosis. Damaging P2RX7 variants occur in a small subset of CNO patients, and rare P2RX7 variants may represent a CNO risk factor. Observations argue for inflammasome inhibition and/or cytokine blockade and may allow future patient stratification and individualized care.
摘要：
慢性非细菌性骨髓炎（CNO），一种主要影响儿童的自身炎症性骨病，会引起疼痛,骨肥大和骨折，影响生活质量和精神运动发育。这项研究调查了P2RX7中与CNO相关的变体，编码ATP依赖性跨膜K通道P2X7，以及它们对NLRP3炎性体组装的影响。两个相关的跨代CNO患者的全外显子组测序，在一个大型CNO队列(N=190)中进行P2RX7的靶测序。将结果与公开可用的数据集和区域对照进行比较(N=1873)。研究结果与人口统计学和临床数据相结合。患者来源的单核细胞和基因修饰的THP-1细胞用于研究钾通量，炎性体组装，焦亡,和细胞因子释放。在两名相关的CNO患者中鉴定出罕见的可能具有破坏性的P2RX7变体。靶向P2RX7测序确定了62例具有罕见变异的CNO患者（32.4％），其中11个（5.8％）携带可能具有破坏性的变体（MAF<1％，SIFT“有害”，多芬“可能会造成伤害”，CADD>20）。这与1873名对照中的83名(4.4%)相比，36例具有罕见且可能具有破坏性的变异（1.9％）。在CNO队列中，与190名随机选择的对照相比,1名(中位数:42对3.7)或更多(≤11名患者)参与者特有的罕见变异体出现过多.具有罕见破坏性变异的患者更频繁地经历胃肠道症状和淋巴结病，而脊髓较少，关节和皮肤受累（牛皮癣）。来自患者的单核细胞来源的巨噬细胞，与CNO相关的P2RX7变体重建的基因修饰的THP-1衍生的巨噬细胞表现出改变的钾通量，炎性体组装，IL-1β和IL-18释放，和焦亡。损害P2RX7变异发生在一小部分CNO患者中，和罕见的P2RX7变异可能代表CNO的危险因素。观察认为炎症小体抑制和/或细胞因子阻断，并可能允许未来的患者分层和个性化护理。
