 Histology and IHC study on postmortem lung sections from rhesus macaques infected with live SARS-CoV. All animals were euthanized 7 days after viral challenge, and anti-SARS-CoV monoclonal antibody was used to identify SARS antigens in the tissue. Representative data from lung sections were shown. Histology samples include: a. Control group. b. High-dose group. c. Placebo group. The arrowheads point to alveoli space filled with proteinaceous fluid. IHC samples include: d. Control group. e. High-dose group. f. Placebo group. Arrows point to cells that were positive for SARS antigen expression. 