CXCL11 and severe acute respiratory syndrome: This can be seen clearly, for example, in vitro, where IFN-α pretreatment of SARS-CoV-infected human HEK 293 cells induces overexpression of CXCL10 and CXCL11 relative to uninfected IFN-α-stimulated cells (Kuri et al., 2009), whereas in the absence of exogenous IFN stimulation SARS-CoV infection is unable to induce IFN-β as well as CXCL10 and CXCL11 expression.