Zhong Yan-feng, Gao Xiao-ming, Wang Sheng-lan, Xie Zhi-gang, Ma Yue, Fang Wei-gang, Zou Wan-zhong, Li Xiu-lan, Zhang Qian-ying, Wang Wei, Zhao Zhen-dong, Gu Jiang
Department of Pathology, Peking University Health Science Center, Beijing 100083, China.
Zhonghua Yi Xue Za Zhi. 2003 Dec 25;83(24):2137-41.
To study the pathologic characteristics and pathogenesis of circulating blood leucocytes infected by severe acute respiratory syndrome associated coronavirus (SARS CoV or SCV) in SARS patients.
Blood samples of 22 SARS patients were studied, and 4 healthy blood samples were observed as negative controls. The white blood cells were collected from whole blood. The ultrastructural characteristics were observed by transmission electron microscopy. CD45RO antibody was used for pre-embedding immunoelectron microscopy. The SARS viral sequence was detected with real-time polymerase chain reaction (RT-PCR).
Coronavirus-like particles were founded in the leukocytes in 6 of the 22 blood samples. Five of them gave positive results in the real-time PCR. The number of granulocytes was increased (P < 0.05) and that of lymphocytes was decreased (P < 0.05) respectively. Immunoelectron microscopy showed that CD45RO positive T lymphocyte decreased to 6% - 7%. Circulating lymphocytes had the highest percentage of infection. The morphologic characteristics of coronavirus-like particles were spherical or oval in shape, about 80 - 120 nm in diameter, with a dense round core and a clear halo around the core. A distinct membrane and club-shaped surface projections were seen in the periphery. The particles were located in the cytoplasm, the cisternae of endoplasmic reticulum, Golgi apparatus and vesicles. Virus entered cells by endocytosis or membrane fusion and was released through a budding process.
Our data suggested that lymphocytes, particularly T cells, were probably the target cells of SARS CoV. The viruses may actively infected the immune cells during SARS CoV acute infection phase and the destruction of target cells may be one of the important reasons for the death of the circulating leukocytes in SARS.
研究严重急性呼吸综合征相关冠状病毒（SARS-CoV或SCV）感染严重急性呼吸综合征（SARS）患者循环血白细胞的病理特征及发病机制。
对22例SARS患者的血样进行研究，并观察4份健康血样作为阴性对照。从全血中收集白细胞。通过透射电子显微镜观察超微结构特征。采用CD45RO抗体进行包埋前免疫电子显微镜检查。用实时聚合酶链反应（RT-PCR）检测SARS病毒序列。
22份血样中的6份在白细胞中发现了冠状病毒样颗粒。其中5份在实时PCR中呈阳性结果。粒细胞数量增加（P<0.05），淋巴细胞数量减少（P<0.05）。免疫电子显微镜显示CD45RO阳性T淋巴细胞降至6%-7%。循环淋巴细胞的感染率最高。冠状病毒样颗粒的形态特征为球形或椭圆形，直径约80-120nm，有致密的圆形核心，核心周围有清晰的晕圈。在外周可见明显的膜和棒状表面突起。颗粒位于细胞质、内质网池、高尔基体和囊泡中。病毒通过内吞作用或膜融合进入细胞，并通过出芽过程释放。
我们的数据表明淋巴细胞，尤其是T细胞，可能是SARS-CoV的靶细胞。在SARS-CoV急性感染期，病毒可能主动感染免疫细胞，靶细胞的破坏可能是SARS患者循环白细胞死亡的重要原因之一。
