Abstract: Objective To establish susceptible animal model of SARS, we studied the pathological and immunological changes on SARS-CoV infected human ACE2 mice. Methods After copy number of human ACE2 transgenic mice was determined by Real-time PCR, the animals were infected with PUMC01 strain of SARS-CoV through nasal cavity. The systemic pathological changes were observed under microscope. The specific antibodies in serum and cytokines of TNF-α, IL-6 and IFN-γ in the supernatant of lung homogenates were detected by ELISA. Results The human ACE2 transgenic mice with a single copy showed more severe interstitial pneumonia accompanied by many extra-pulmonary organ damages. The specific antibody was found in a few of transgenic mice. Levels of TNF-α, IL-6 and IFN-γ in the supernatant of lung homogenates from transgenic mice were increased more markedly after they were inoculated with SARS-CoV. Conclusion Resembling human SARS case, the human ACE2 transgenic mice with infected by SARS-CoV had similar pathological and immunological changes. This small animal model can be used to study pathogenesis of SARS and evaluate the effect of anti-SARS-CoV drugs.

Key words: angiotensin-converting enzyme 2, transgenic mice, severe acute respiratory syndrome, pathology, immunology