CXCL11 and COVID-19: Among the proinflammatory interleukins and chemokines genes analyzed in the present work, IL6, CXCL10 and CXCL11 showed a differential expression (upregulation) in PBCs of COVID-19 patients on hospital admission relative to controls, the upregulation being proportional to the severity of the disease course for CXCL11.