inly enhances its circulating/systemic activity. Interestingly, a recent integrative bioinformatics analysis shows that the gene expression of ACE2 in human bronchial cells infected with SARS-CoV is dramatically increased 24h after infection and remained at a high level for at least 2 days, suggesting that ACE2 may be involved in a positive feedback loop post-infection [25]. In the same report, it has been shown that ACE2 expression level in bronchial epithelium obtained by brushing from asthmatic and normal subje