CXCL12 and severe acute respiratory syndrome: In addition, several chemokines, including CCL5, CXCL12 and CCL20 were significantly increased in the lungs of SARS-CoV-infected aged monkeys here, which is consistent with the finding of elevated chemokine signaling genes in the aged lungs of cynomolgous macaques during SARS-CoV infection by microarray [22].