严重急性呼吸综合征冠状病毒S蛋白引起肺损伤的可能机制  

The possible mechanism of lung injury induced by severe acute respiratory syndrome coronavirus spike glycoprotein

作　　者：杨新艳[1] 要国华[1] 徐军[1] 钟南山[1] 

机构地区：[1]广州医学院第一附属医院广州呼吸疾病研究所,510120

出　　处：《中华结核和呼吸杂志》2006年第9期587-590,共4页Chinese Journal of Tuberculosis and Respiratory Diseases

基　　金：国家自然科学基金(30340029); 广东省教育厅非典专项经费

摘　　要：目的研究严重急性呼吸综合征冠状病毒(SARS-CoV)通过微血管内皮细胞释放细胞因子/趋化因子,介导急性肺损伤的可能机制。方法广州呼吸疾病研究所2003年2月至5月确诊为 SARS 的住院患者23例,男15例,女8例,年龄27～55岁,平均(36±6)岁。用液相蛋白芯片系统测定 SARS 患者不同阶段血中的细胞因子/趋化因子水平,免疫组化方法检测 SARS 患者肺组织中γ干扰素诱导蛋白10(interferon-γ inducible protein 10,IP-10)的表达;通过昆虫-杆状病毒表达系统表达 SARS-CoV 的 S 蛋白,并经镍亲和磁珠纯化,将重组的 S 蛋白作用于人脐静脉内皮细胞(HUVEC)观察其形态学变化并检测相应细胞因子/趋化因子的变化。结果 IP-10在健康对照组水平较低[(1200±500)ng/L],疾病早期就显著增高[(7600±2400)ng/L,P<0.01],并且在进展期[(8100±2300)ng/L,P<0.01]和疾病晚期[(8000±2800)ng/L,P<0.01]都保持显著增高的水平,直至恢复期[(1 250±450)ng/L,P>0.05]才正常,其在 SARS 患者肺组织显著表达。S 蛋白作用于人血管内皮细胞可引起细胞内出现空泡,细胞变圆有脱落,随时间延长细胞破碎溶解。基础状态下内皮细胞并不生成 IP-10,S 蛋白(5、20、40 mg/L)分别作用后可见 IP-10生成呈显著量效反应,如12 h分别为[(179±34)、(889±212)、(1676±199)ng/L,P 均<0.05]。结论 (1)SARS-CoV 感染的患者血中 IP-10活性显著增高,一直持续到恢复期,肺中 IP-10的表达增加。(2)SARS-CoV 可通过其 S蛋白诱导血管内皮细胞合成释放 IP-10,损害内皮细胞。(3)SARS-CoV 的 S 蛋白诱导 IP-10在宿主细胞的生成不依赖 IFN-γ。Objective To investigate the role of severe acute respiratory syndrome coronavirus （SARS-CoV） in the induction of acute lung injury by promoting the synthesis of chemokine/cytokines in human endothelial cells. Methods Twenty-three SARS patients were enrolled in this study, comprising 15 male and 8 female, aged 27 -55 years, mean （36 ± 6） years. They were treated at Guangzhou Institute of Respiratory Disease from February to May in 2003. Chemokines/cytokines in the blood of patients with SARS were dynamically screened by liquid chip system. The lung was studied histopathologically using immunohistochemical technique. Spike giycoprotein of SARS-CoV was recombined by using insect- baculovirus expression system and Nickel affinity Magnet Beads, and then used to stimulate cultured human umbilical vein endothelial cells （HUVEC）. Morphological changes of HUVEC were observed by microscope. Levels of chemokines/cytokines involved in immunoreaction in response to virus infection were detected in the supernatants of those cells cultured with the Spike giycoprotein by liquid chip system. Results Interferon-γ inducible protein 10（IP-10） was markedly elevated in the blood during the early stage of SARS [ （7 600 ± 2 400）ng/L, P 〈 0. 01 ], and remained at a high level in the progressive stage [ （8 100 ± 2 300 ） ng/L, P 〈 0. 01 ] and the end stage [ （ 8 000 ± 2 800 ） ng/L, P 〈 0. 01 ] until convalescence [ （ 1 250 ± 450 ） ng/L,P〉0. 05]. Moreover,IP-10 was highly expressed in the lung. Vacuoles appeared in part of HUVEC after Spike glycoprotein stimulation. As time going on, the HUVEC turned to be round in shape and even disrupted. Under normal condition, no detectable IP-10 was found in HUVEC. A high level of IP-10 [ （179 ± 34）, （889 ± 212 ）, （1 676 ± 199 ）ng/L, all P 〈 0.05 ] was detected in the HUVEC 12 h after Spike glycoprotein（ 5,20,40 mg/L） stimulation respectively, and presented with a significant dose-dependent response. Conclusions （ 1 ） A significant

关 键 词：严重急性呼吸综合征 冠状病毒 内皮细胞 γ干扰素诱导蛋白10 Spike糖蛋白 

分 类 号：R511.9[医药卫生—内科学]