ACE2 and severe acute respiratory syndrome: Ding et al. [39] systematically examined the presence of SARS-CoV in tissues of deceased SARS patients using immunohistochemistry and in situ hybridization; the authors found that SARS-CoV was present in the lungs, small intestine, kidneys, liver, pancreas, cerebrum, and other tissues, indicating that ACE2-expressing organs may serve as direct targets of SARS-CoV.