Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University, Homburg, Germany.
Department of Environment & Biodiversity, University of Salzburg, Salzburg, Austria.
Front Immunol. 2022 Apr 12;13:872695. doi: 10.3389/fimmu.2022.872695. eCollection 2022.
The frequent severe COVID-19 course in patients with periodontitis suggests a link of the aetiopathogenesis of both diseases. The formation of intravascular neutrophil extracellular traps (NETs) is crucial to the pathogenesis of severe COVID-19. Periodontitis is characterised by an increased level of circulating NETs, a propensity for increased NET formation, delayed NET clearance and low-grade endotoxemia (LGE). The latter has an enormous impact on innate immunity and susceptibility to infection with SARS-CoV-2. LPS binds the SARS-CoV-2 spike protein and this complex, which is more active than unbound LPS, precipitates massive NET formation. Thus, circulating NET formation is the common denominator in both COVID-19 and periodontitis and other diseases with low-grade endotoxemia like diabetes, obesity and cardiovascular diseases (CVD) also increase the risk to develop severe COVID-19. Here we discuss the role of propensity for increased NET formation, DNase I deficiency and low-grade endotoxaemia in periodontitis as aggravating factors for the severe course of COVID-19 and possible strategies for the diminution of increased levels of circulating periodontitis-derived NETs in COVID-19 with periodontitis comorbidity.
牙周炎患者 COVID-19 频繁出现严重症状表明这两种疾病在发病机制上存在关联。血管内中性粒细胞胞外诱捕网（NETs）的形成对 COVID-19 严重症状的发病机制至关重要。牙周炎的特点是循环 NETs 水平升高、NET 形成倾向增加、NET 清除延迟和低度内毒素血症（LGE）。后者对内因免疫和对 SARS-CoV-2 感染的易感性有巨大影响。LPS 与 SARS-CoV-2 刺突蛋白结合，这种复合物比未结合的 LPS 更活跃，会引发大量 NETs 的形成。因此，循环 NETs 的形成是 COVID-19 和牙周炎以及其他伴有低度内毒素血症的疾病（如糖尿病、肥胖症和心血管疾病（CVD））的共同特征，这些疾病也会增加发展为 COVID-19 重症的风险。在这里，我们讨论了在 COVID-19 中，NET 形成倾向增加、DNase I 缺乏和低度内毒素血症作为牙周炎加重因素的作用，以及在 COVID-19 合并牙周炎时减少循环牙周炎衍生 NETs 水平升高的可能策略。
