CXCL11 and COVID-19: Concentrations of IL-15, granzyme B, CCL2, CCL7, CCL8, CXCL1, CXCL10, CXCL11, and CXCL12α, i.e., inflammatory mediators associated with attraction or activation of monocytes, lymphocytes, and NK cells, were significantly increased in the BAL fluid of patients with COVID-19 in the mid- or late phase compared with patients in the acute phase of the coinfection (Figure 7, A–I).