Multiple organ infection and the pathogenesis of SARS

Gu, Jiang; Gong, Encong; Zhang, Bo; Zheng, Jie; Gao, Zifen; Zhong, Yanfeng; Zou, Wanzhong; Zhan, Jun; Wang, Shenglan; Xie, Zhigang; Zhuang, Hui; Wu, Bingquan; Zhong, Haohao; Shao, Hongquan; Fang, Weigang; Gao, Dongshia; Pei, Fei; Li, Xingwang; He, Zhongpin; Xu, Danzhen; Shi, Xeying; Anderson, Virginia M.; Leong, Anthony S.-Y.

SARS viral sequences also were detected in the epithelial cells of the trachea, bronchi, and bronchioles by in situ hybridization ( Fig. 1 J) . More than 50% of ciliated epithelial cells in the trachea displayed positive cytoplasmic in situ hybridization; no positive signal was detected in the negative control when an unrelated probe was used ( Fig.1 K) . The interstitial tissue was thickened with fibrin exudation and organization. Many alveoli were collapsed, filled with fluid, and exhibited hyaline membranes. Cellular infiltration was not obvious. Bar, 50 m. (C) In situ hybridization of SARS genomic sequence of the lung from a SARS victim who died 62 d after the onset of high fever detected a large number of pulmonary epithelial cells (small arrows) that contained the virus. Multinuclear giant syncytial cells found in the alveoli contained a large amount of SARS viral sequences (large arrows). Bar, 80 m. (D) In situ hybridization of SARS genomic sequence of the lung from a SARS victim who died 35 d after the initial symptoms showed macrophages (large arrows) in an alveolus, and many pulmonary epithelial cells (small arrows) contained the virus. Bar, 100 m. (E) Blood vessel in SARS lungdouble labeling, immunohistochemistry of CD68-brown (thin arrows). In situ hybridization of SARS viral sequence-black (thick arrows). A mixed color (arrowheads) indicates that monocyte was infected by SARS virus. The black color also may overshadow the brown color when both are present in the same blood cells and the in situ hybridization signal is very strong. Bar, 100 m.