To test whether pro-inflammatory cytokine expression was induced during SARS-CoV-∆E-8a-dup infection, we analyzed the expression of several genes previously associated with SARS-CoV pathology [24, 57] including: chemokine (C-X-C motif) ligand 10 (CXCL10), chemokine (C-C motif) ligand 2 (CCL2) and interleukin 6 (IL6) (S3 Table). This evidence concerns the gene CCL2 and infection.