When two Tg hACE2 mouse strains with varying levels of hACE2 expression, AC70 (higher hACE2, lethally susceptible to infection) and AC22 (lower hACE2, transient weight loss, not susceptible to lethality), were compared, induction of Cxcl1, Ccl2 and Ccl5 in the lung was delayed in the strain susceptible to lethal SARS-CoV infection compared to the resistant Tg mice. Here, CCL2 is linked to severe acute respiratory syndrome.