Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a vast number of infections and deaths that deeply affect the world. When the virus encounters the host cell, it binds to angiotensin-converting enzyme 2, then the S protein of the virus is broken down by the transmembrane protease serine 2 with the help of furin, allowing the virus to enter the cell. The elevated inflammatory cytokines suggest that a cytokine storm, also known as cytokine release syndrome, may play a major role in the pathology of COVID-19. Therefore, the aim of this study is to investigate the relationship between circulating furin levels, disease severity, and inflammation in patients with SARS-CoV-2. A total of 52 SARS-CoV-2 patients and 36 healthy control participants were included in this study. SARS- CoV-2 patients were scored by the disease activity score. Serum furin, presepsin, and interleukin-6 (IL-6) levels were assessed using an enzyme-linked immunosorbent assay. The mean furin, presepsin, and IL-6 levels were significantly higher in the peripheral blood of SARS-CoV-2 compared to the controls (p < 0.001). There were close positive relationship between serum furin and IL-6, furin and presepsin, and furin and disease severity (r = 0.793, p < 0001; r = 0.521, p < 0.001; and r = 0,533, p < 0.001, respectively) in patients with SARS-CoV-2. These results suggest that furin may contribute to the exacerbation of SARS-CoV-2 infection and increased inflammation, and could be used as a predictor of disease severity in COVID-19 patients.

2019 冠状病毒病 (COVID-19) 是由严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 引起的传染病，已导致大量感染和死亡，深刻影响了世界。当病毒遇到宿主细胞时，它与血管紧张素转换酶2结合，然后病毒的S蛋白在弗林蛋白酶的帮助下被跨膜蛋白酶丝氨酸2分解，使病毒进入细胞。炎症细胞因子升高表明细胞因子风暴（也称为细胞因子释放综合征）可能在 COVID-19 的病理学中发挥重要作用。因此，本研究的目的是调查 SARS-CoV-2 患者循环弗林蛋白酶水平、疾病严重程度和炎症之间的关系。本研究共纳入 52 名 SARS-CoV-2 患者和 36 名健康对照参与者。通过疾病活动评分对 SARS-CoV-2 患者进行评分。使用酶联免疫吸附测定评估血清弗林蛋白酶、前蛋白酶和白细胞介素 6 (IL-6) 水平。与对照组相比，SARS-CoV-2 外周血中弗林蛋白酶、前蛋白酶和 IL-6 的平均水平显着升高 ( p  < 0.001)。血清弗林蛋白酶和IL-6、弗林蛋白酶和presepsin以及弗林蛋白酶和疾病严重程度之间存在密切的正相关关系（分别为r  = 0.793，p  < 0001；r  = 0.521，p  < 0.001；和r  = 0,533，p  < 0.001） SARS-CoV-2 患者。这些结果表明，弗林蛋白酶可能导致 SARS-CoV-2 感染加剧和炎症增加，并可用作 COVID-19 患者疾病严重程度的预测因子。