A novel subset of putative stem/progenitor CD34(+)Oct-4(+) cells is the major target for SARS coronavirus in human lung

Chen, Yongxiong; Chan, Vera Sau-Fong; Zheng, Bojian; Chan, Kelvin Yuen-Kwong; Xu, Xiaoning; To, Leo Yuk-Fai; Huang, Fang-Ping; Khoo, Ui-Soon; Lin, Chen-Lung Steve

ed labeling, one indicated by a white arrow in m; also visible in n and p), followed by FISH for ACE2 (green labeling, some indicated by green arrows in n) and ISH for L-SIGN (purple labeling, some indicated by pink arrows in p). DAPI counterstaining is in q. Some of the ACE2 Ï© CD34 Ï© Oct4 Ï© L-SIGN Ï© cells are close to surfactant A Ï© cells (g and k) or cytokeratin Ï© cells (p). Panels of each row represent results on the same section of a patient. Results are representative of eight patients with lung cancer. Bar, 20 m. (B) Fresh lung tissues resected from cancer patients were cut into small blocks, exposed to SARS-CoV for 16 h, and studied by IHC for surfactant A (brown labeling in a and b, one indicated by a yellow arrow in b; also visible in e), for SARS antigen (red labeling, indicated by a red arrow in b; also visible in c), followed by FISH for CD34 (green expressed both CD34 and Oct-4 ( Fig. 3 B , d and e, green and purple, respectively, and Fig. S8 ). In separate sections, triplecolor staining confi rmed that no cytokeratin or surfactant expression was colocalized with SARS antigen (Fig. S9) .